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  %08x  %08x  %8ld  %s\n" :
 208                         "   %-5s     %03X    %08x  %08lx  %08lx  %8ld  %s\n";
 209
 210                 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 211                                 (unsigned long)r->func, (unsigned long)r->data,
 212                                 r->matches, r->ident);
 213         }
 214 }
 215
 216 static void can_print_recv_banner(struct seq_file *m)
 217 {
 218         /*
 219          *                  can1.  00000000  00000000  00000000
 220          *                 .......          0  tp20
 221          */
 222         seq_puts(m, "  device   can_id   can_mask  function"
 223                         "  userdata   matches  ident\n");
 224 }
 225
 226 static int can_stats_proc_show(struct seq_file *m, void *v)
 227 {
 228         seq_putc(m, '\n');
 229         seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
 230         seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
 231         seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
 232
 233         seq_putc(m, '\n');
 234
 235         if (can_stattimer.function == can_stat_update) {
 236                 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 237                                 can_stats.total_rx_match_ratio);
 238
 239                 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 240                                 can_stats.total_tx_rate);
 241                 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 242                                 can_stats.total_rx_rate);
 243
 244                 seq_putc(m, '\n');
 245
 246                 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 247                                 can_stats.current_rx_match_ratio);
 248
 249                 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 250                                 can_stats.current_tx_rate);
 251                 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 252                                 can_stats.current_rx_rate);
 253
 254                 seq_putc(m, '\n');
 255
 256                 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 257                                 can_stats.max_rx_match_ratio);
 258
 259                 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 260                                 can_stats.max_tx_rate);
 261                 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 262                                 can_stats.max_rx_rate);
 263
 264                 seq_putc(m, '\n');
 265         }
 266
 267         seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 268                         can_pstats.rcv_entries);
 269         seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 270                         can_pstats.rcv_entries_max);
 271
 272         if (can_pstats.stats_reset)
 273                 seq_printf(m, "\n %8ld statistic resets (STR)\n",
 274                                 can_pstats.stats_reset);
 275
 276         if (can_pstats.user_reset)
 277                 seq_printf(m, " %8ld user statistic resets (USTR)\n",
 278                                 can_pstats.user_reset);
 279
 280         seq_putc(m, '\n');
 281         return 0;
 282 }
 283
 284 static int can_stats_proc_open(struct inode *inode, struct file *file)
 285 {
 286         return single_open(file, can_stats_proc_show, NULL);
 287 }
 288
 289 static const struct file_operations can_stats_proc_fops = {
 290         .owner          = THIS_MODULE,
 291         .open           = can_stats_proc_open,
 292         .read           = seq_read,
 293         .llseek         = seq_lseek,
 294         .release        = single_release,
 295 };
 296
 297 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 298 {
 299         user_reset = 1;
 300
 301         if (can_stattimer.function == can_stat_update) {
 302                 seq_printf(m, "Scheduled statistic reset #%ld.\n",
 303                                 can_pstats.stats_reset + 1);
 304
 305         } else {
 306                 if (can_stats.jiffies_init != jiffies)
 307                         can_init_stats();
 308
 309                 seq_printf(m, "Performed statistic reset #%ld.\n",
 310                                 can_pstats.stats_reset);
 311         }
 312         return 0;
 313 }
 314
 315 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 316 {
 317         return single_open(file, can_reset_stats_proc_show, NULL);
 318 }
 319
 320 static const struct file_operations can_reset_stats_proc_fops = {
 321         .owner          = THIS_MODULE,
 322         .open           = can_reset_stats_proc_open,
 323         .read           = seq_read,
 324         .llseek         = seq_lseek,
 325         .release        = single_release,
 326 };
 327
 328 static int can_version_proc_show(struct seq_file *m, void *v)
 329 {
 330         seq_printf(m, "%s\n", CAN_VERSION_STRING);
 331         return 0;
 332 }
 333
 334 static int can_version_proc_open(struct inode *inode, struct file *file)
 335 {
 336         return single_open(file, can_version_proc_show, NULL);
 337 }
 338
 339 static const struct file_operations can_version_proc_fops = {
 340         .owner          = THIS_MODULE,
 341         .open           = can_version_proc_open,
 342         .read           = seq_read,
 343         .llseek         = seq_lseek,
 344         .release        = single_release,
 345 };
 346
 347 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 348                                              struct net_device *dev,
 349                                              struct dev_rcv_lists *d)
 350 {
 351         if (!hlist_empty(&d->rx[idx])) {
 352                 can_print_recv_banner(m);
 353                 can_print_rcvlist(m, &d->rx[idx], dev);
 354         } else
 355                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 356
 357 }
 358
 359 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 360 {
 361         /* double cast to prevent GCC warning */
 362         int idx = (int)(long)m->private;
 363         struct net_device *dev;
 364         struct dev_rcv_lists *d;
 365
 366         seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 367
 368         rcu_read_lock();
 369
 370         /* receive list for 'all' CAN devices (dev == NULL) */
 371         d = &can_rx_alldev_list;
 372         can_rcvlist_proc_show_one(m, idx, NULL, d);
 373
 374         /* receive list for registered CAN devices */
 375         for_each_netdev_rcu(&init_net, dev) {
 376                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 377                         can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 378         }
 379
 380         rcu_read_unlock();
 381
 382         seq_putc(m, '\n');
 383         return 0;
 384 }
 385
 386 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 387 {
 388         return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
 389 }
 390
 391 static const struct file_operations can_rcvlist_proc_fops = {
 392         .owner          = THIS_MODULE,
 393         .open           = can_rcvlist_proc_open,
 394         .read           = seq_read,
 395         .llseek         = seq_lseek,
 396         .release        = single_release,
 397 };
 398
 399 static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
 400                                                  struct net_device *dev,
 401                                                  struct dev_rcv_lists *d)
 402 {
 403         int i;
 404         int all_empty = 1;
 405
 406         /* check wether at least one list is non-empty */
 407         for (i = 0; i < 0x800; i++)
 408                 if (!hlist_empty(&d->rx_sff[i])) {
 409                         all_empty = 0;
 410                         break;
 411                 }
 412
 413         if (!all_empty) {
 414                 can_print_recv_banner(m);
 415                 for (i = 0; i < 0x800; i++) {
 416                         if (!hlist_empty(&d->rx_sff[i]))
 417                                 can_print_rcvlist(m, &d->rx_sff[i], dev);
 418                 }
 419         } else
 420                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 421 }
 422
 423 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 424 {
 425         struct net_device *dev;
 426         struct dev_rcv_lists *d;
 427
 428         /* RX_SFF */
 429         seq_puts(m, "\nreceive list 'rx_sff':\n");
 430
 431         rcu_read_lock();
 432
 433         /* sff receive list for 'all' CAN devices (dev == NULL) */
 434         d = &can_rx_alldev_list;
 435         can_rcvlist_sff_proc_show_one(m, NULL, d);
 436
 437         /* sff receive list for registered CAN devices */
 438         for_each_netdev_rcu(&init_net, dev) {
 439                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 440                         can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
 441         }
 442
 443         rcu_read_unlock();
 444
 445         seq_putc(m, '\n');
 446         return 0;
 447 }
 448
 449 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 450 {
 451         return single_open(file, can_rcvlist_sff_proc_show, NULL);
 452 }
 453
 454 static const struct file_operations can_rcvlist_sff_proc_fops = {
 455         .owner          = THIS_MODULE,
 456         .open           = can_rcvlist_sff_proc_open,
 457         .read           = seq_read,
 458         .llseek         = seq_lseek,
 459         .release        = single_release,
 460 };
 461
 462 /*
 463  * proc utility functions
 464  */
 465
 466 static void can_remove_proc_readentry(const char *name)
 467 {
 468         if (can_dir)
 469                 remove_proc_entry(name, can_dir);
 470 }
 471
 472 /*
 473  * can_init_proc - create main CAN proc directory and procfs entries
 474  */
 475 void can_init_proc(void)
 476 {
 477         /* create /proc/net/can directory */
 478         can_dir = proc_mkdir("can", init_net.proc_net);
 479
 480         if (!can_dir) {
 481                 printk(KERN_INFO "can: failed to create /proc/net/can . "
 482                        "CONFIG_PROC_FS missing?\n");
 483                 return;
 484         }
 485
 486         /* own procfs entries from the AF_CAN core */
 487         pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
 488                                       &can_version_proc_fops);
 489         pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
 490                                       &can_stats_proc_fops);
 491         pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
 492                                       &can_reset_stats_proc_fops);
 493         pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
 494                                            &can_rcvlist_proc_fops, (void *)RX_ERR);
 495         pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
 496                                            &can_rcvlist_proc_fops, (void *)RX_ALL);
 497         pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
 498                                            &can_rcvlist_proc_fops, (void *)RX_FIL);
 499         pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
 500                                            &can_rcvlist_proc_fops, (void *)RX_INV);
 501         pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
 502                                            &can_rcvlist_proc_fops, (void *)RX_EFF);
 503         pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
 504                                       &can_rcvlist_sff_proc_fops);
 505 }
 506
 507 /*
 508  * can_remove_proc - remove procfs entries and main CAN proc directory
 509  */
 510 void can_remove_proc(void)
 511 {
 512         if (pde_version)
 513                 can_remove_proc_readentry(CAN_PROC_VERSION);
 514
 515         if (pde_stats)
 516                 can_remove_proc_readentry(CAN_PROC_STATS);
 517
 518         if (pde_reset_stats)
 519                 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
 520
 521         if (pde_rcvlist_err)
 522                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
 523
 524         if (pde_rcvlist_all)
 525                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
 526
 527         if (pde_rcvlist_fil)
 528                 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
 529
 530         if (pde_rcvlist_inv)
 531                 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
 532
 533         if (pde_rcvlist_eff)
 534                 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
 535
 536         if (pde_rcvlist_sff)
 537                 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
 538
 539         if (can_dir)
 540                 proc_net_remove(&init_net, "can");
 541 }