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