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  * Send feedback to <socketcan-users@lists.berlios.de>
  41  *
  42  */
  43
  44 #include <linux/module.h>
  45 #include <linux/proc_fs.h>
  46 #include <linux/list.h>
  47 #include <linux/rcupdate.h>
  48 #include <linux/if_arp.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 struct proc_dir_entry *can_dir;
  68 static struct proc_dir_entry *pde_version;
  69 static struct proc_dir_entry *pde_stats;
  70 static struct proc_dir_entry *pde_reset_stats;
  71 static struct proc_dir_entry *pde_rcvlist_all;
  72 static struct proc_dir_entry *pde_rcvlist_fil;
  73 static struct proc_dir_entry *pde_rcvlist_inv;
  74 static struct proc_dir_entry *pde_rcvlist_sff;
  75 static struct proc_dir_entry *pde_rcvlist_eff;
  76 static struct proc_dir_entry *pde_rcvlist_err;
  77
  78 static int user_reset;
  79
  80 static const char rx_list_name[][8] = {
  81         [RX_ERR] = "rx_err",
  82         [RX_ALL] = "rx_all",
  83         [RX_FIL] = "rx_fil",
  84         [RX_INV] = "rx_inv",
  85         [RX_EFF] = "rx_eff",
  86 };
  87
  88 /* receive filters subscribed for 'all' CAN devices */
  89 extern struct dev_rcv_lists can_rx_alldev_list;
  90
  91 /*
  92  * af_can statistics stuff
  93  */
  94
  95 static void can_init_stats(void)
  96 {
  97         /*
  98          * This memset function is called from a timer context (when
  99          * can_stattimer is active which is the default) OR in a process
 100          * context (reading the proc_fs when can_stattimer is disabled).
 101          */
 102         memset(&can_stats, 0, sizeof(can_stats));
 103         can_stats.jiffies_init = jiffies;
 104
 105         can_pstats.stats_reset++;
 106
 107         if (user_reset) {
 108                 user_reset = 0;
 109                 can_pstats.user_reset++;
 110         }
 111 }
 112
 113 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 114                                unsigned long count)
 115 {
 116         unsigned long rate;
 117
 118         if (oldjif == newjif)
 119                 return 0;
 120
 121         /* see can_stat_update() - this should NEVER happen! */
 122         if (count > (ULONG_MAX / HZ)) {
 123                 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
 124                        count);
 125                 return 99999999;
 126         }
 127
 128         rate = (count * HZ) / (newjif - oldjif);
 129
 130         return rate;
 131 }
 132
 133 void can_stat_update(unsigned long data)
 134 {
 135         unsigned long j = jiffies; /* snapshot */
 136
 137         /* restart counting in timer context on user request */
 138         if (user_reset)
 139                 can_init_stats();
 140
 141         /* restart counting on jiffies overflow */
 142         if (j < can_stats.jiffies_init)
 143                 can_init_stats();
 144
 145         /* prevent overflow in calc_rate() */
 146         if (can_stats.rx_frames > (ULONG_MAX / HZ))
 147                 can_init_stats();
 148
 149         /* prevent overflow in calc_rate() */
 150         if (can_stats.tx_frames > (ULONG_MAX / HZ))
 151                 can_init_stats();
 152
 153         /* matches overflow - very improbable */
 154         if (can_stats.matches > (ULONG_MAX / 100))
 155                 can_init_stats();
 156
 157         /* calc total values */
 158         if (can_stats.rx_frames)
 159                 can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
 160                         can_stats.rx_frames;
 161
 162         can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
 163                                             can_stats.tx_frames);
 164         can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
 165                                             can_stats.rx_frames);
 166
 167         /* calc current values */
 168         if (can_stats.rx_frames_delta)
 169                 can_stats.current_rx_match_ratio =
 170                         (can_stats.matches_delta * 100) /
 171                         can_stats.rx_frames_delta;
 172
 173         can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
 174         can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
 175
 176         /* check / update maximum values */
 177         if (can_stats.max_tx_rate < can_stats.current_tx_rate)
 178                 can_stats.max_tx_rate = can_stats.current_tx_rate;
 179
 180         if (can_stats.max_rx_rate < can_stats.current_rx_rate)
 181                 can_stats.max_rx_rate = can_stats.current_rx_rate;
 182
 183         if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
 184                 can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
 185
 186         /* clear values for 'current rate' calculation */
 187         can_stats.tx_frames_delta = 0;
 188         can_stats.rx_frames_delta = 0;
 189         can_stats.matches_delta   = 0;
 190
 191         /* restart timer (one second) */
 192         mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
 193 }
 194
 195 /*
 196  * proc read functions
 197  */
 198
 199 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
 200                               struct net_device *dev)
 201 {
 202         struct receiver *r;
 203         struct hlist_node *n;
 204
 205         hlist_for_each_entry_rcu(r, n, rx_list, list) {
 206                 char *fmt = (r->can_id & CAN_EFF_FLAG)?
 207                         "   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
 208                         "   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
 209
 210                 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 211                                 r->func, r->data, r->matches, r->ident);
 212         }
 213 }
 214
 215 static void can_print_recv_banner(struct seq_file *m)
 216 {
 217         /*
 218          *                  can1.  00000000  00000000  00000000
 219          *                 .......          0  tp20
 220          */
 221         seq_puts(m, "  device   can_id   can_mask  function"
 222                         "  userdata   matches  ident\n");
 223 }
 224
 225 static int can_stats_proc_show(struct seq_file *m, void *v)
 226 {
 227         seq_putc(m, '\n');
 228         seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
 229         seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
 230         seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
 231
 232         seq_putc(m, '\n');
 233
 234         if (can_stattimer.function == can_stat_update) {
 235                 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 236                                 can_stats.total_rx_match_ratio);
 237
 238                 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 239                                 can_stats.total_tx_rate);
 240                 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 241                                 can_stats.total_rx_rate);
 242
 243                 seq_putc(m, '\n');
 244
 245                 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 246                                 can_stats.current_rx_match_ratio);
 247
 248                 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 249                                 can_stats.current_tx_rate);
 250                 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 251                                 can_stats.current_rx_rate);
 252
 253                 seq_putc(m, '\n');
 254
 255                 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 256                                 can_stats.max_rx_match_ratio);
 257
 258                 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 259                                 can_stats.max_tx_rate);
 260                 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 261                                 can_stats.max_rx_rate);
 262
 263                 seq_putc(m, '\n');
 264         }
 265
 266         seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 267                         can_pstats.rcv_entries);
 268         seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 269                         can_pstats.rcv_entries_max);
 270
 271         if (can_pstats.stats_reset)
 272                 seq_printf(m, "\n %8ld statistic resets (STR)\n",
 273                                 can_pstats.stats_reset);
 274
 275         if (can_pstats.user_reset)
 276                 seq_printf(m, " %8ld user statistic resets (USTR)\n",
 277                                 can_pstats.user_reset);
 278
 279         seq_putc(m, '\n');
 280         return 0;
 281 }
 282
 283 static int can_stats_proc_open(struct inode *inode, struct file *file)
 284 {
 285         return single_open(file, can_stats_proc_show, NULL);
 286 }
 287
 288 static const struct file_operations can_stats_proc_fops = {
 289         .owner          = THIS_MODULE,
 290         .open           = can_stats_proc_open,
 291         .read           = seq_read,
 292         .llseek         = seq_lseek,
 293         .release        = single_release,
 294 };
 295
 296 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 297 {
 298         user_reset = 1;
 299
 300         if (can_stattimer.function == can_stat_update) {
 301                 seq_printf(m, "Scheduled statistic reset #%ld.\n",
 302                                 can_pstats.stats_reset + 1);
 303
 304         } else {
 305                 if (can_stats.jiffies_init != jiffies)
 306                         can_init_stats();
 307
 308                 seq_printf(m, "Performed statistic reset #%ld.\n",
 309                                 can_pstats.stats_reset);
 310         }
 311         return 0;
 312 }
 313
 314 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 315 {
 316         return single_open(file, can_reset_stats_proc_show, NULL);
 317 }
 318
 319 static const struct file_operations can_reset_stats_proc_fops = {
 320         .owner          = THIS_MODULE,
 321         .open           = can_reset_stats_proc_open,
 322         .read           = seq_read,
 323         .llseek         = seq_lseek,
 324         .release        = single_release,
 325 };
 326
 327 static int can_version_proc_show(struct seq_file *m, void *v)
 328 {
 329         seq_printf(m, "%s\n", CAN_VERSION_STRING);
 330         return 0;
 331 }
 332
 333 static int can_version_proc_open(struct inode *inode, struct file *file)
 334 {
 335         return single_open(file, can_version_proc_show, NULL);
 336 }
 337
 338 static const struct file_operations can_version_proc_fops = {
 339         .owner          = THIS_MODULE,
 340         .open           = can_version_proc_open,
 341         .read           = seq_read,
 342         .llseek         = seq_lseek,
 343         .release        = single_release,
 344 };
 345
 346 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 347                                              struct net_device *dev,
 348                                              struct dev_rcv_lists *d)
 349 {
 350         if (!hlist_empty(&d->rx[idx])) {
 351                 can_print_recv_banner(m);
 352                 can_print_rcvlist(m, &d->rx[idx], dev);
 353         } else
 354                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 355
 356 }
 357
 358 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 359 {
 360         /* double cast to prevent GCC warning */
 361         int idx = (int)(long)m->private;
 362         struct net_device *dev;
 363         struct dev_rcv_lists *d;
 364
 365         seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 366
 367         rcu_read_lock();
 368
 369         /* receive list for 'all' CAN devices (dev == NULL) */
 370         d = &can_rx_alldev_list;
 371         can_rcvlist_proc_show_one(m, idx, NULL, d);
 372
 373         /* receive list for registered CAN devices */
 374         for_each_netdev_rcu(&init_net, dev) {
 375                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 376                         can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 377         }
 378
 379         rcu_read_unlock();
 380
 381         seq_putc(m, '\n');
 382         return 0;
 383 }
 384
 385 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 386 {
 387         return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
 388 }
 389
 390 static const struct file_operations can_rcvlist_proc_fops = {
 391         .owner          = THIS_MODULE,
 392         .open           = can_rcvlist_proc_open,
 393         .read           = seq_read,
 394         .llseek         = seq_lseek,
 395         .release        = single_release,
 396 };
 397
 398 static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
 399                                                  struct net_device *dev,
 400                                                  struct dev_rcv_lists *d)
 401 {
 402         int i;
 403         int all_empty = 1;
 404
 405         /* check wether at least one list is non-empty */
 406         for (i = 0; i < 0x800; i++)
 407                 if (!hlist_empty(&d->rx_sff[i])) {
 408                         all_empty = 0;
 409                         break;
 410                 }
 411
 412         if (!all_empty) {
 413                 can_print_recv_banner(m);
 414                 for (i = 0; i < 0x800; i++) {
 415                         if (!hlist_empty(&d->rx_sff[i]))
 416                                 can_print_rcvlist(m, &d->rx_sff[i], dev);
 417                 }
 418         } else
 419                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 420 }
 421
 422 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 423 {
 424         struct net_device *dev;
 425         struct dev_rcv_lists *d;
 426
 427         /* RX_SFF */
 428         seq_puts(m, "\nreceive list 'rx_sff':\n");
 429
 430         rcu_read_lock();
 431
 432         /* sff receive list for 'all' CAN devices (dev == NULL) */
 433         d = &can_rx_alldev_list;
 434         can_rcvlist_sff_proc_show_one(m, NULL, d);
 435
 436         /* sff receive list for registered CAN devices */
 437         for_each_netdev_rcu(&init_net, dev) {
 438                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 439                         can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
 440         }
 441
 442         rcu_read_unlock();
 443
 444         seq_putc(m, '\n');
 445         return 0;
 446 }
 447
 448 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 449 {
 450         return single_open(file, can_rcvlist_sff_proc_show, NULL);
 451 }
 452
 453 static const struct file_operations can_rcvlist_sff_proc_fops = {
 454         .owner          = THIS_MODULE,
 455         .open           = can_rcvlist_sff_proc_open,
 456         .read           = seq_read,
 457         .llseek         = seq_lseek,
 458         .release        = single_release,
 459 };
 460
 461 /*
 462  * proc utility functions
 463  */
 464
 465 static void can_remove_proc_readentry(const char *name)
 466 {
 467         if (can_dir)
 468                 remove_proc_entry(name, can_dir);
 469 }
 470
 471 /*
 472  * can_init_proc - create main CAN proc directory and procfs entries
 473  */
 474 void can_init_proc(void)
 475 {
 476         /* create /proc/net/can directory */
 477         can_dir = proc_mkdir("can", init_net.proc_net);
 478
 479         if (!can_dir) {
 480                 printk(KERN_INFO "can: failed to create /proc/net/can . "
 481                        "CONFIG_PROC_FS missing?\n");
 482                 return;
 483         }
 484
 485         /* own procfs entries from the AF_CAN core */
 486         pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
 487                                       &can_version_proc_fops);
 488         pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
 489                                       &can_stats_proc_fops);
 490         pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
 491                                       &can_reset_stats_proc_fops);
 492         pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
 493                                            &can_rcvlist_proc_fops, (void *)RX_ERR);
 494         pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
 495                                            &can_rcvlist_proc_fops, (void *)RX_ALL);
 496         pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
 497                                            &can_rcvlist_proc_fops, (void *)RX_FIL);
 498         pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
 499                                            &can_rcvlist_proc_fops, (void *)RX_INV);
 500         pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
 501                                            &can_rcvlist_proc_fops, (void *)RX_EFF);
 502         pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
 503                                       &can_rcvlist_sff_proc_fops);
 504 }
 505
 506 /*
 507  * can_remove_proc - remove procfs entries and main CAN proc directory
 508  */
 509 void can_remove_proc(void)
 510 {
 511         if (pde_version)
 512                 can_remove_proc_readentry(CAN_PROC_VERSION);
 513
 514         if (pde_stats)
 515                 can_remove_proc_readentry(CAN_PROC_STATS);
 516
 517         if (pde_reset_stats)
 518                 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
 519
 520         if (pde_rcvlist_err)
 521                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
 522
 523         if (pde_rcvlist_all)
 524                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
 525
 526         if (pde_rcvlist_fil)
 527                 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
 528
 529         if (pde_rcvlist_inv)
 530                 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
 531
 532         if (pde_rcvlist_eff)
 533                 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
 534
 535         if (pde_rcvlist_sff)
 536                 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
 537
 538         if (can_dir)
 539                 proc_net_remove(&init_net, "can");
 540 }