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 };
  84
  85 /*
  86  * af_can statistics stuff
  87  */
  88
  89 static void can_init_stats(void)
  90 {
  91         /*
  92          * This memset function is called from a timer context (when
  93          * can_stattimer is active which is the default) OR in a process
  94          * context (reading the proc_fs when can_stattimer is disabled).
  95          */
  96         memset(&can_stats, 0, sizeof(can_stats));
  97         can_stats.jiffies_init = jiffies;
  98
  99         can_pstats.stats_reset++;
 100
 101         if (user_reset) {
 102                 user_reset = 0;
 103                 can_pstats.user_reset++;
 104         }
 105 }
 106
 107 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 108                                unsigned long count)
 109 {
 110         unsigned long rate;
 111
 112         if (oldjif == newjif)
 113                 return 0;
 114
 115         /* see can_stat_update() - this should NEVER happen! */
 116         if (count > (ULONG_MAX / HZ)) {
 117                 printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
 118                        count);
 119                 return 99999999;
 120         }
 121
 122         rate = (count * HZ) / (newjif - oldjif);
 123
 124         return rate;
 125 }
 126
 127 void can_stat_update(unsigned long data)
 128 {
 129         unsigned long j = jiffies; /* snapshot */
 130
 131         /* restart counting in timer context on user request */
 132         if (user_reset)
 133                 can_init_stats();
 134
 135         /* restart counting on jiffies overflow */
 136         if (j < can_stats.jiffies_init)
 137                 can_init_stats();
 138
 139         /* prevent overflow in calc_rate() */
 140         if (can_stats.rx_frames > (ULONG_MAX / HZ))
 141                 can_init_stats();
 142
 143         /* prevent overflow in calc_rate() */
 144         if (can_stats.tx_frames > (ULONG_MAX / HZ))
 145                 can_init_stats();
 146
 147         /* matches overflow - very improbable */
 148         if (can_stats.matches > (ULONG_MAX / 100))
 149                 can_init_stats();
 150
 151         /* calc total values */
 152         if (can_stats.rx_frames)
 153                 can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
 154                         can_stats.rx_frames;
 155
 156         can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
 157                                             can_stats.tx_frames);
 158         can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
 159                                             can_stats.rx_frames);
 160
 161         /* calc current values */
 162         if (can_stats.rx_frames_delta)
 163                 can_stats.current_rx_match_ratio =
 164                         (can_stats.matches_delta * 100) /
 165                         can_stats.rx_frames_delta;
 166
 167         can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
 168         can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
 169
 170         /* check / update maximum values */
 171         if (can_stats.max_tx_rate < can_stats.current_tx_rate)
 172                 can_stats.max_tx_rate = can_stats.current_tx_rate;
 173
 174         if (can_stats.max_rx_rate < can_stats.current_rx_rate)
 175                 can_stats.max_rx_rate = can_stats.current_rx_rate;
 176
 177         if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
 178                 can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
 179
 180         /* clear values for 'current rate' calculation */
 181         can_stats.tx_frames_delta = 0;
 182         can_stats.rx_frames_delta = 0;
 183         can_stats.matches_delta   = 0;
 184
 185         /* restart timer (one second) */
 186         mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
 187 }
 188
 189 /*
 190  * proc read functions
 191  */
 192
 193 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
 194                               struct net_device *dev)
 195 {
 196         struct receiver *r;
 197
 198         hlist_for_each_entry_rcu(r, rx_list, list) {
 199                 char *fmt = (r->can_id & CAN_EFF_FLAG)?
 200                         "   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
 201                         "   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
 202
 203                 seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 204                                 r->func, r->data, r->matches, r->ident);
 205         }
 206 }
 207
 208 static void can_print_recv_banner(struct seq_file *m)
 209 {
 210         /*
 211          *                  can1.  00000000  00000000  00000000
 212          *                 .......          0  tp20
 213          */
 214         seq_puts(m, "  device   can_id   can_mask  function"
 215                         "  userdata   matches  ident\n");
 216 }
 217
 218 static int can_stats_proc_show(struct seq_file *m, void *v)
 219 {
 220         seq_putc(m, '\n');
 221         seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
 222         seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
 223         seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
 224
 225         seq_putc(m, '\n');
 226
 227         if (can_stattimer.function == can_stat_update) {
 228                 seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 229                                 can_stats.total_rx_match_ratio);
 230
 231                 seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 232                                 can_stats.total_tx_rate);
 233                 seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 234                                 can_stats.total_rx_rate);
 235
 236                 seq_putc(m, '\n');
 237
 238                 seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 239                                 can_stats.current_rx_match_ratio);
 240
 241                 seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 242                                 can_stats.current_tx_rate);
 243                 seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 244                                 can_stats.current_rx_rate);
 245
 246                 seq_putc(m, '\n');
 247
 248                 seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 249                                 can_stats.max_rx_match_ratio);
 250
 251                 seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 252                                 can_stats.max_tx_rate);
 253                 seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 254                                 can_stats.max_rx_rate);
 255
 256                 seq_putc(m, '\n');
 257         }
 258
 259         seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 260                         can_pstats.rcv_entries);
 261         seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 262                         can_pstats.rcv_entries_max);
 263
 264         if (can_pstats.stats_reset)
 265                 seq_printf(m, "\n %8ld statistic resets (STR)\n",
 266                                 can_pstats.stats_reset);
 267
 268         if (can_pstats.user_reset)
 269                 seq_printf(m, " %8ld user statistic resets (USTR)\n",
 270                                 can_pstats.user_reset);
 271
 272         seq_putc(m, '\n');
 273         return 0;
 274 }
 275
 276 static int can_stats_proc_open(struct inode *inode, struct file *file)
 277 {
 278         return single_open(file, can_stats_proc_show, NULL);
 279 }
 280
 281 static const struct file_operations can_stats_proc_fops = {
 282         .owner          = THIS_MODULE,
 283         .open           = can_stats_proc_open,
 284         .read           = seq_read,
 285         .llseek         = seq_lseek,
 286         .release        = single_release,
 287 };
 288
 289 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 290 {
 291         user_reset = 1;
 292
 293         if (can_stattimer.function == can_stat_update) {
 294                 seq_printf(m, "Scheduled statistic reset #%ld.\n",
 295                                 can_pstats.stats_reset + 1);
 296
 297         } else {
 298                 if (can_stats.jiffies_init != jiffies)
 299                         can_init_stats();
 300
 301                 seq_printf(m, "Performed statistic reset #%ld.\n",
 302                                 can_pstats.stats_reset);
 303         }
 304         return 0;
 305 }
 306
 307 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 308 {
 309         return single_open(file, can_reset_stats_proc_show, NULL);
 310 }
 311
 312 static const struct file_operations can_reset_stats_proc_fops = {
 313         .owner          = THIS_MODULE,
 314         .open           = can_reset_stats_proc_open,
 315         .read           = seq_read,
 316         .llseek         = seq_lseek,
 317         .release        = single_release,
 318 };
 319
 320 static int can_version_proc_show(struct seq_file *m, void *v)
 321 {
 322         seq_printf(m, "%s\n", CAN_VERSION_STRING);
 323         return 0;
 324 }
 325
 326 static int can_version_proc_open(struct inode *inode, struct file *file)
 327 {
 328         return single_open(file, can_version_proc_show, NULL);
 329 }
 330
 331 static const struct file_operations can_version_proc_fops = {
 332         .owner          = THIS_MODULE,
 333         .open           = can_version_proc_open,
 334         .read           = seq_read,
 335         .llseek         = seq_lseek,
 336         .release        = single_release,
 337 };
 338
 339 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 340                                              struct net_device *dev,
 341                                              struct dev_rcv_lists *d)
 342 {
 343         if (!hlist_empty(&d->rx[idx])) {
 344                 can_print_recv_banner(m);
 345                 can_print_rcvlist(m, &d->rx[idx], dev);
 346         } else
 347                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 348
 349 }
 350
 351 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 352 {
 353         /* double cast to prevent GCC warning */
 354         int idx = (int)(long)m->private;
 355         struct net_device *dev;
 356         struct dev_rcv_lists *d;
 357
 358         seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 359
 360         rcu_read_lock();
 361
 362         /* receive list for 'all' CAN devices (dev == NULL) */
 363         d = &can_rx_alldev_list;
 364         can_rcvlist_proc_show_one(m, idx, NULL, d);
 365
 366         /* receive list for registered CAN devices */
 367         for_each_netdev_rcu(&init_net, dev) {
 368                 if (dev->type == ARPHRD_CAN && dev->ml_priv)
 369                         can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 370         }
 371
 372         rcu_read_unlock();
 373
 374         seq_putc(m, '\n');
 375         return 0;
 376 }
 377
 378 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 379 {
 380         return single_open(file, can_rcvlist_proc_show, PDE_DATA(inode));
 381 }
 382
 383 static const struct file_operations can_rcvlist_proc_fops = {
 384         .owner          = THIS_MODULE,
 385         .open           = can_rcvlist_proc_open,
 386         .read           = seq_read,
 387         .llseek         = seq_lseek,
 388         .release        = single_release,
 389 };
 390
 391 static inline void can_rcvlist_proc_show_array(struct seq_file *m,
 392                                                struct net_device *dev,
 393                                                struct hlist_head *rcv_array,
 394                                                unsigned int rcv_array_sz)
 395 {
 396         unsigned int i;
 397         int all_empty = 1;
 398
 399         /* check whether at least one list is non-empty */
 400         for (i = 0; i < rcv_array_sz; i++)
 401                 if (!hlist_empty(&rcv_array[i])) {
 402                         all_empty = 0;
 403                         break;
 404                 }
 405
 406         if (!all_empty) {
 407                 can_print_recv_banner(m);
 408                 for (i = 0; i < rcv_array_sz; i++) {
 409                         if (!hlist_empty(&rcv_array[i]))
 410                                 can_print_rcvlist(m, &rcv_array[i], dev);
 411                 }
 412         } else
 413                 seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 414 }
 415
 416 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 417 {
 418         struct net_device *dev;
 419         struct dev_rcv_lists *d;
 420
 421         /* RX_SFF */
 422         seq_puts(m, "\nreceive list 'rx_sff':\n");
 423
 424         rcu_read_lock();
 425
 426         /* sff receive list for 'all' CAN devices (dev == NULL) */
 427         d = &can_rx_alldev_list;
 428         can_rcvlist_proc_show_array(m, NULL, d->rx_sff, ARRAY_SIZE(d->rx_sff));
 429
 430         /* sff receive list for registered CAN devices */
 431         for_each_netdev_rcu(&init_net, dev) {
 432                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 433                         d = dev->ml_priv;
 434                         can_rcvlist_proc_show_array(m, dev, d->rx_sff,
 435                                                     ARRAY_SIZE(d->rx_sff));
 436                 }
 437         }
 438
 439         rcu_read_unlock();
 440
 441         seq_putc(m, '\n');
 442         return 0;
 443 }
 444
 445 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 446 {
 447         return single_open(file, can_rcvlist_sff_proc_show, NULL);
 448 }
 449
 450 static const struct file_operations can_rcvlist_sff_proc_fops = {
 451         .owner          = THIS_MODULE,
 452         .open           = can_rcvlist_sff_proc_open,
 453         .read           = seq_read,
 454         .llseek         = seq_lseek,
 455         .release        = single_release,
 456 };
 457
 458
 459 static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
 460 {
 461         struct net_device *dev;
 462         struct dev_rcv_lists *d;
 463
 464         /* RX_EFF */
 465         seq_puts(m, "\nreceive list 'rx_eff':\n");
 466
 467         rcu_read_lock();
 468
 469         /* eff receive list for 'all' CAN devices (dev == NULL) */
 470         d = &can_rx_alldev_list;
 471         can_rcvlist_proc_show_array(m, NULL, d->rx_eff, ARRAY_SIZE(d->rx_eff));
 472
 473         /* eff receive list for registered CAN devices */
 474         for_each_netdev_rcu(&init_net, dev) {
 475                 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
 476                         d = dev->ml_priv;
 477                         can_rcvlist_proc_show_array(m, dev, d->rx_eff,
 478                                                     ARRAY_SIZE(d->rx_eff));
 479                 }
 480         }
 481
 482         rcu_read_unlock();
 483
 484         seq_putc(m, '\n');
 485         return 0;
 486 }
 487
 488 static int can_rcvlist_eff_proc_open(struct inode *inode, struct file *file)
 489 {
 490         return single_open(file, can_rcvlist_eff_proc_show, NULL);
 491 }
 492
 493 static const struct file_operations can_rcvlist_eff_proc_fops = {
 494         .owner          = THIS_MODULE,
 495         .open           = can_rcvlist_eff_proc_open,
 496         .read           = seq_read,
 497         .llseek         = seq_lseek,
 498         .release        = single_release,
 499 };
 500
 501 /*
 502  * proc utility functions
 503  */
 504
 505 static void can_remove_proc_readentry(const char *name)
 506 {
 507         if (can_dir)
 508                 remove_proc_entry(name, can_dir);
 509 }
 510
 511 /*
 512  * can_init_proc - create main CAN proc directory and procfs entries
 513  */
 514 void can_init_proc(void)
 515 {
 516         /* create /proc/net/can directory */
 517         can_dir = proc_mkdir("can", init_net.proc_net);
 518
 519         if (!can_dir) {
 520                 pr_info("can: failed to create /proc/net/can.\n");
 521                 return;
 522         }
 523
 524         /* own procfs entries from the AF_CAN core */
 525         pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
 526                                       &can_version_proc_fops);
 527         pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
 528                                       &can_stats_proc_fops);
 529         pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
 530                                       &can_reset_stats_proc_fops);
 531         pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
 532                                            &can_rcvlist_proc_fops, (void *)RX_ERR);
 533         pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
 534                                            &can_rcvlist_proc_fops, (void *)RX_ALL);
 535         pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
 536                                            &can_rcvlist_proc_fops, (void *)RX_FIL);
 537         pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
 538                                            &can_rcvlist_proc_fops, (void *)RX_INV);
 539         pde_rcvlist_eff = proc_create(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
 540                                       &can_rcvlist_eff_proc_fops);
 541         pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
 542                                       &can_rcvlist_sff_proc_fops);
 543 }
 544
 545 /*
 546  * can_remove_proc - remove procfs entries and main CAN proc directory
 547  */
 548 void can_remove_proc(void)
 549 {
 550         if (pde_version)
 551                 can_remove_proc_readentry(CAN_PROC_VERSION);
 552
 553         if (pde_stats)
 554                 can_remove_proc_readentry(CAN_PROC_STATS);
 555
 556         if (pde_reset_stats)
 557                 can_remove_proc_readentry(CAN_PROC_RESET_STATS);
 558
 559         if (pde_rcvlist_err)
 560                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
 561
 562         if (pde_rcvlist_all)
 563                 can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
 564
 565         if (pde_rcvlist_fil)
 566                 can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
 567
 568         if (pde_rcvlist_inv)
 569                 can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
 570
 571         if (pde_rcvlist_eff)
 572                 can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
 573
 574         if (pde_rcvlist_sff)
 575                 can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
 576
 577         if (can_dir)
 578                 remove_proc_entry("can", init_net.proc_net);
 579 }