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_stats_proc_open(struct inode *inode, struct file *file)
 274 {
 275         return single_open_net(inode, file, can_stats_proc_show);
 276 }
 277
 278 static const struct file_operations can_stats_proc_fops = {
 279         .open           = can_stats_proc_open,
 280         .read           = seq_read,
 281         .llseek         = seq_lseek,
 282         .release        = single_release,
 283 };
 284
 285 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 286 {
 287         struct net *net = m->private;
 288         struct s_pstats *can_pstats = net->can.can_pstats;
 289         struct s_stats *can_stats = net->can.can_stats;
 290
 291         user_reset = 1;
 292
 293         if (net->can.can_stattimer.function == can_stat_update) {
 294                 seq_printf(m, "Scheduled statistic reset #%ld.\n",
 295                                 can_pstats->stats_reset + 1);
 296         } else {
 297                 if (can_stats->jiffies_init != jiffies)
 298                         can_init_stats(net);
 299
 300                 seq_printf(m, "Performed statistic reset #%ld.\n",
 301                                 can_pstats->stats_reset);
 302         }
 303         return 0;
 304 }
 305
 306 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 307 {
 308         return single_open_net(inode, file, can_reset_stats_proc_show);
 309 }
 310
 311 static const struct file_operations can_reset_stats_proc_fops = {
 312         .open           = can_reset_stats_proc_open,
 313         .read           = seq_read,
 314         .llseek         = seq_lseek,
 315         .release        = single_release,
 316 };
 317
 318 static int can_version_proc_show(struct seq_file *m, void *v)
 319 {
 320         seq_printf(m, "%s\n", CAN_VERSION_STRING);
 321         return 0;
 322 }
 323
 324 static int can_version_proc_open(struct inode *inode, struct file *file)
 325 {
 326         return single_open_net(inode, file, can_version_proc_show);
 327 }
 328
 329 static const struct file_operations can_version_proc_fops = {
 330         .open           = can_version_proc_open,
 331         .read           = seq_read,
 332         .llseek         = seq_lseek,
 333         .release        = single_release,
 334 };
 335
 336 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 337                                              struct net_device *dev,
 338                                              struct can_dev_rcv_lists *d)
 339 {
 340         if (!hlist_empty(&d->rx[idx])) {
 341                 can_print_recv_banner(m);
 342                 can_print_rcvlist(m, &d->rx[idx], dev);
 343         } else
 344                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 345
 346 }
 347
 348 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 349 {
 350         /* double cast to prevent GCC warning */
 351         int idx = (int)(long)PDE_DATA(m->file->f_inode);
 352         struct net_device *dev;
 353         struct can_dev_rcv_lists *d;
 354         struct net *net = m->private;
 355
 356         seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 357
 358         rcu_read_lock();
 359
 360         /* receive list for 'all' CAN devices (dev == NULL) */
 361         d = net->can.can_rx_alldev_list;
 362         can_rcvlist_proc_show_one(m, idx, NULL, d);
 363
 364         /* receive list for registered CAN devices */
 365         for_each_netdev_rcu(net, dev) {
 366                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 367                         can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 368         }
 369
 370         rcu_read_unlock();
 371
 372         seq_putc(m, '\n');
 373         return 0;
 374 }
 375
 376 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 377 {
 378         return single_open_net(inode, file, can_rcvlist_proc_show);
 379 }
 380
 381 static const struct file_operations can_rcvlist_proc_fops = {
 382         .open           = can_rcvlist_proc_open,
 383         .read           = seq_read,
 384         .llseek         = seq_lseek,
 385         .release        = single_release,
 386 };
 387
 388 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
 389                                                struct net_device *dev,
 390                                                struct hlist_head *rcv_array,
 391                                                unsigned int rcv_array_sz)
 392 {
 393         unsigned int i;
 394         int all_empty = 1;
 395
 396         /* check whether at least one list is non-empty */
 397         for (i = 0; i < rcv_array_sz; i++)
 398                 if (!hlist_empty(&rcv_array[i])) {
 399                         all_empty = 0;
 400                         break;
 401                 }
 402
 403         if (!all_empty) {
 404                 can_print_recv_banner(m);
 405                 for (i = 0; i < rcv_array_sz; i++) {
 406                         if (!hlist_empty(&rcv_array[i]))
 407                                 can_print_rcvlist(m, &rcv_array[i], dev);
 408                 }
 409         } else
 410                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 411 }
 412
 413 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 414 {
 415         struct net_device *dev;
 416         struct can_dev_rcv_lists *d;
 417         struct net *net = m->private;
 418
 419         /* RX_SFF */
 420         seq_puts(m, "\nreceive list 'rx_sff':\n");
 421
 422         rcu_read_lock();
 423
 424         /* sff receive list for 'all' CAN devices (dev == NULL) */
 425         d = net->can.can_rx_alldev_list;
 426         can_rcvlist_proc_show_array(m, NULL, d->rx_sff, ARRAY_SIZE(d->rx_sff));
 427
 428         /* sff receive list for registered CAN devices */
 429         for_each_netdev_rcu(net, dev) {
 430                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 431                         d = dev->ml_priv;
 432                         can_rcvlist_proc_show_array(m, dev, d->rx_sff,
 433                                                     ARRAY_SIZE(d->rx_sff));
 434                 }
 435         }
 436
 437         rcu_read_unlock();
 438
 439         seq_putc(m, '\n');
 440         return 0;
 441 }
 442
 443 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 444 {
 445         return single_open_net(inode, file, can_rcvlist_sff_proc_show);
 446 }
 447
 448 static const struct file_operations can_rcvlist_sff_proc_fops = {
 449         .open           = can_rcvlist_sff_proc_open,
 450         .read           = seq_read,
 451         .llseek         = seq_lseek,
 452         .release        = single_release,
 453 };
 454
 455
 456 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 457 {
 458         struct net_device *dev;
 459         struct can_dev_rcv_lists *d;
 460         struct net *net = m->private;
 461
 462         /* RX_EFF */
 463         seq_puts(m, "\nreceive list 'rx_eff':\n");
 464
 465         rcu_read_lock();
 466
 467         /* eff receive list for 'all' CAN devices (dev == NULL) */
 468         d = net->can.can_rx_alldev_list;
 469         can_rcvlist_proc_show_array(m, NULL, d->rx_eff, ARRAY_SIZE(d->rx_eff));
 470
 471         /* eff receive list for registered CAN devices */
 472         for_each_netdev_rcu(net, dev) {
 473                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 474                         d = dev->ml_priv;
 475                         can_rcvlist_proc_show_array(m, dev, d->rx_eff,
 476                                                     ARRAY_SIZE(d->rx_eff));
 477                 }
 478         }
 479
 480         rcu_read_unlock();
 481
 482         seq_putc(m, '\n');
 483         return 0;
 484 }
 485
 486 static int can_rcvlist_eff_proc_open(struct inode *inode, struct file *file)
 487 {
 488         return single_open_net(inode, file, can_rcvlist_eff_proc_show);
 489 }
 490
 491 static const struct file_operations can_rcvlist_eff_proc_fops = {
 492         .open           = can_rcvlist_eff_proc_open,
 493         .read           = seq_read,
 494         .llseek         = seq_lseek,
 495         .release        = single_release,
 496 };
 497
 498 /*
 499  * can_init_proc - create main CAN proc directory and procfs entries
 500  */
 501 void can_init_proc(struct net *net)
 502 {
 503         /* create /proc/net/can directory */
 504         net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net);
 505
 506         if (!net->can.proc_dir) {
 507                 printk(KERN_INFO "can: failed to create /proc/net/can . "
 508                            "CONFIG_PROC_FS missing?\n");
 509                 return;
 510         }
 511
 512         /* own procfs entries from the AF_CAN core */
 513         net->can.pde_version     = proc_create(CAN_PROC_VERSION, 0644,
 514                                                net->can.proc_dir,
 515                                                &can_version_proc_fops);
 516         net->can.pde_stats       = proc_create(CAN_PROC_STATS, 0644,
 517                                                net->can.proc_dir,
 518                                                &can_stats_proc_fops);
 519         net->can.pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644,
 520                                                net->can.proc_dir,
 521                                                &can_reset_stats_proc_fops);
 522         net->can.pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644,
 523                                                     net->can.proc_dir,
 524                                                     &can_rcvlist_proc_fops,
 525                                                     (void *)RX_ERR);
 526         net->can.pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644,
 527                                                     net->can.proc_dir,
 528                                                     &can_rcvlist_proc_fops,
 529                                                     (void *)RX_ALL);
 530         net->can.pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644,
 531                                                     net->can.proc_dir,
 532                                                     &can_rcvlist_proc_fops,
 533                                                     (void *)RX_FIL);
 534         net->can.pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644,
 535                                                     net->can.proc_dir,
 536                                                     &can_rcvlist_proc_fops,
 537                                                     (void *)RX_INV);
 538         net->can.pde_rcvlist_eff = proc_create(CAN_PROC_RCVLIST_EFF, 0644,
 539                                                net->can.proc_dir,
 540                                                &can_rcvlist_eff_proc_fops);
 541         net->can.pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644,
 542                                                net->can.proc_dir,
 543                                                &can_rcvlist_sff_proc_fops);
 544 }
 545
 546 /*
 547  * can_remove_proc - remove procfs entries and main CAN proc directory
 548  */
 549 void can_remove_proc(struct net *net)
 550 {
 551         if (net->can.pde_version)
 552                 remove_proc_entry(CAN_PROC_VERSION, net->can.proc_dir);
 553
 554         if (net->can.pde_stats)
 555                 remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir);
 556
 557         if (net->can.pde_reset_stats)
 558                 remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir);
 559
 560         if (net->can.pde_rcvlist_err)
 561                 remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir);
 562
 563         if (net->can.pde_rcvlist_all)
 564                 remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir);
 565
 566         if (net->can.pde_rcvlist_fil)
 567                 remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir);
 568
 569         if (net->can.pde_rcvlist_inv)
 570                 remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir);
 571
 572         if (net->can.pde_rcvlist_eff)
 573                 remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir);
 574
 575         if (net->can.pde_rcvlist_sff)
 576                 remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir);
 577
 578         if (net->can.proc_dir)
 579                 remove_proc_entry("can", net->proc_net);
 580 }