linux/net/can/proc.c
<<
>>
Prefs
   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
  65static struct proc_dir_entry *can_dir;
  66static struct proc_dir_entry *pde_version;
  67static struct proc_dir_entry *pde_stats;
  68static struct proc_dir_entry *pde_reset_stats;
  69static struct proc_dir_entry *pde_rcvlist_all;
  70static struct proc_dir_entry *pde_rcvlist_fil;
  71static struct proc_dir_entry *pde_rcvlist_inv;
  72static struct proc_dir_entry *pde_rcvlist_sff;
  73static struct proc_dir_entry *pde_rcvlist_eff;
  74static struct proc_dir_entry *pde_rcvlist_err;
  75
  76static int user_reset;
  77
  78static 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/*
  87 * af_can statistics stuff
  88 */
  89
  90static void can_init_stats(void)
  91{
  92        /*
  93         * This memset function is called from a timer context (when
  94         * can_stattimer is active which is the default) OR in a process
  95         * context (reading the proc_fs when can_stattimer is disabled).
  96         */
  97        memset(&can_stats, 0, sizeof(can_stats));
  98        can_stats.jiffies_init = jiffies;
  99
 100        can_pstats.stats_reset++;
 101
 102        if (user_reset) {
 103                user_reset = 0;
 104                can_pstats.user_reset++;
 105        }
 106}
 107
 108static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 109                               unsigned long count)
 110{
 111        unsigned long rate;
 112
 113        if (oldjif == newjif)
 114                return 0;
 115
 116        /* see can_stat_update() - this should NEVER happen! */
 117        if (count > (ULONG_MAX / HZ)) {
 118                printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
 119                       count);
 120                return 99999999;
 121        }
 122
 123        rate = (count * HZ) / (newjif - oldjif);
 124
 125        return rate;
 126}
 127
 128void can_stat_update(unsigned long data)
 129{
 130        unsigned long j = jiffies; /* snapshot */
 131
 132        /* restart counting in timer context on user request */
 133        if (user_reset)
 134                can_init_stats();
 135
 136        /* restart counting on jiffies overflow */
 137        if (j < can_stats.jiffies_init)
 138                can_init_stats();
 139
 140        /* prevent overflow in calc_rate() */
 141        if (can_stats.rx_frames > (ULONG_MAX / HZ))
 142                can_init_stats();
 143
 144        /* prevent overflow in calc_rate() */
 145        if (can_stats.tx_frames > (ULONG_MAX / HZ))
 146                can_init_stats();
 147
 148        /* matches overflow - very improbable */
 149        if (can_stats.matches > (ULONG_MAX / 100))
 150                can_init_stats();
 151
 152        /* calc total values */
 153        if (can_stats.rx_frames)
 154                can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
 155                        can_stats.rx_frames;
 156
 157        can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
 158                                            can_stats.tx_frames);
 159        can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
 160                                            can_stats.rx_frames);
 161
 162        /* calc current values */
 163        if (can_stats.rx_frames_delta)
 164                can_stats.current_rx_match_ratio =
 165                        (can_stats.matches_delta * 100) /
 166                        can_stats.rx_frames_delta;
 167
 168        can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
 169        can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
 170
 171        /* check / update maximum values */
 172        if (can_stats.max_tx_rate < can_stats.current_tx_rate)
 173                can_stats.max_tx_rate = can_stats.current_tx_rate;
 174
 175        if (can_stats.max_rx_rate < can_stats.current_rx_rate)
 176                can_stats.max_rx_rate = can_stats.current_rx_rate;
 177
 178        if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
 179                can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
 180
 181        /* clear values for 'current rate' calculation */
 182        can_stats.tx_frames_delta = 0;
 183        can_stats.rx_frames_delta = 0;
 184        can_stats.matches_delta   = 0;
 185
 186        /* restart timer (one second) */
 187        mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
 188}
 189
 190/*
 191 * proc read functions
 192 */
 193
 194static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
 195                              struct net_device *dev)
 196{
 197        struct receiver *r;
 198        struct hlist_node *n;
 199
 200        hlist_for_each_entry_rcu(r, n, rx_list, list) {
 201                char *fmt = (r->can_id & CAN_EFF_FLAG)?
 202                        "   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
 203                        "   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";
 204
 205                seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 206                                r->func, r->data, r->matches, r->ident);
 207        }
 208}
 209
 210static void can_print_recv_banner(struct seq_file *m)
 211{
 212        /*
 213         *                  can1.  00000000  00000000  00000000
 214         *                 .......          0  tp20
 215         */
 216        seq_puts(m, "  device   can_id   can_mask  function"
 217                        "  userdata   matches  ident\n");
 218}
 219
 220static int can_stats_proc_show(struct seq_file *m, void *v)
 221{
 222        seq_putc(m, '\n');
 223        seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
 224        seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
 225        seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);
 226
 227        seq_putc(m, '\n');
 228
 229        if (can_stattimer.function == can_stat_update) {
 230                seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 231                                can_stats.total_rx_match_ratio);
 232
 233                seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 234                                can_stats.total_tx_rate);
 235                seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 236                                can_stats.total_rx_rate);
 237
 238                seq_putc(m, '\n');
 239
 240                seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 241                                can_stats.current_rx_match_ratio);
 242
 243                seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 244                                can_stats.current_tx_rate);
 245                seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 246                                can_stats.current_rx_rate);
 247
 248                seq_putc(m, '\n');
 249
 250                seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 251                                can_stats.max_rx_match_ratio);
 252
 253                seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 254                                can_stats.max_tx_rate);
 255                seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 256                                can_stats.max_rx_rate);
 257
 258                seq_putc(m, '\n');
 259        }
 260
 261        seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 262                        can_pstats.rcv_entries);
 263        seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 264                        can_pstats.rcv_entries_max);
 265
 266        if (can_pstats.stats_reset)
 267                seq_printf(m, "\n %8ld statistic resets (STR)\n",
 268                                can_pstats.stats_reset);
 269
 270        if (can_pstats.user_reset)
 271                seq_printf(m, " %8ld user statistic resets (USTR)\n",
 272                                can_pstats.user_reset);
 273
 274        seq_putc(m, '\n');
 275        return 0;
 276}
 277
 278static int can_stats_proc_open(struct inode *inode, struct file *file)
 279{
 280        return single_open(file, can_stats_proc_show, NULL);
 281}
 282
 283static const struct file_operations can_stats_proc_fops = {
 284        .owner          = THIS_MODULE,
 285        .open           = can_stats_proc_open,
 286        .read           = seq_read,
 287        .llseek         = seq_lseek,
 288        .release        = single_release,
 289};
 290
 291static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 292{
 293        user_reset = 1;
 294
 295        if (can_stattimer.function == can_stat_update) {
 296                seq_printf(m, "Scheduled statistic reset #%ld.\n",
 297                                can_pstats.stats_reset + 1);
 298
 299        } else {
 300                if (can_stats.jiffies_init != jiffies)
 301                        can_init_stats();
 302
 303                seq_printf(m, "Performed statistic reset #%ld.\n",
 304                                can_pstats.stats_reset);
 305        }
 306        return 0;
 307}
 308
 309static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 310{
 311        return single_open(file, can_reset_stats_proc_show, NULL);
 312}
 313
 314static const struct file_operations can_reset_stats_proc_fops = {
 315        .owner          = THIS_MODULE,
 316        .open           = can_reset_stats_proc_open,
 317        .read           = seq_read,
 318        .llseek         = seq_lseek,
 319        .release        = single_release,
 320};
 321
 322static int can_version_proc_show(struct seq_file *m, void *v)
 323{
 324        seq_printf(m, "%s\n", CAN_VERSION_STRING);
 325        return 0;
 326}
 327
 328static int can_version_proc_open(struct inode *inode, struct file *file)
 329{
 330        return single_open(file, can_version_proc_show, NULL);
 331}
 332
 333static const struct file_operations can_version_proc_fops = {
 334        .owner          = THIS_MODULE,
 335        .open           = can_version_proc_open,
 336        .read           = seq_read,
 337        .llseek         = seq_lseek,
 338        .release        = single_release,
 339};
 340
 341static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 342                                             struct net_device *dev,
 343                                             struct dev_rcv_lists *d)
 344{
 345        if (!hlist_empty(&d->rx[idx])) {
 346                can_print_recv_banner(m);
 347                can_print_rcvlist(m, &d->rx[idx], dev);
 348        } else
 349                seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 350
 351}
 352
 353static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 354{
 355        /* double cast to prevent GCC warning */
 356        int idx = (int)(long)m->private;
 357        struct net_device *dev;
 358        struct dev_rcv_lists *d;
 359
 360        seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);
 361
 362        rcu_read_lock();
 363
 364        /* receive list for 'all' CAN devices (dev == NULL) */
 365        d = &can_rx_alldev_list;
 366        can_rcvlist_proc_show_one(m, idx, NULL, d);
 367
 368        /* receive list for registered CAN devices */
 369        for_each_netdev_rcu(&init_net, dev) {
 370                if (dev->type == ARPHRD_CAN && dev->ml_priv)
 371                        can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 372        }
 373
 374        rcu_read_unlock();
 375
 376        seq_putc(m, '\n');
 377        return 0;
 378}
 379
 380static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 381{
 382        return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
 383}
 384
 385static const struct file_operations can_rcvlist_proc_fops = {
 386        .owner          = THIS_MODULE,
 387        .open           = can_rcvlist_proc_open,
 388        .read           = seq_read,
 389        .llseek         = seq_lseek,
 390        .release        = single_release,
 391};
 392
 393static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
 394                                                 struct net_device *dev,
 395                                                 struct dev_rcv_lists *d)
 396{
 397        int i;
 398        int all_empty = 1;
 399
 400        /* check wether at least one list is non-empty */
 401        for (i = 0; i < 0x800; i++)
 402                if (!hlist_empty(&d->rx_sff[i])) {
 403                        all_empty = 0;
 404                        break;
 405                }
 406
 407        if (!all_empty) {
 408                can_print_recv_banner(m);
 409                for (i = 0; i < 0x800; i++) {
 410                        if (!hlist_empty(&d->rx_sff[i]))
 411                                can_print_rcvlist(m, &d->rx_sff[i], dev);
 412                }
 413        } else
 414                seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 415}
 416
 417static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 418{
 419        struct net_device *dev;
 420        struct dev_rcv_lists *d;
 421
 422        /* RX_SFF */
 423        seq_puts(m, "\nreceive list 'rx_sff':\n");
 424
 425        rcu_read_lock();
 426
 427        /* sff receive list for 'all' CAN devices (dev == NULL) */
 428        d = &can_rx_alldev_list;
 429        can_rcvlist_sff_proc_show_one(m, NULL, d);
 430
 431        /* sff receive list for registered CAN devices */
 432        for_each_netdev_rcu(&init_net, dev) {
 433                if (dev->type == ARPHRD_CAN && dev->ml_priv)
 434                        can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
 435        }
 436
 437        rcu_read_unlock();
 438
 439        seq_putc(m, '\n');
 440        return 0;
 441}
 442
 443static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 444{
 445        return single_open(file, can_rcvlist_sff_proc_show, NULL);
 446}
 447
 448static const struct file_operations can_rcvlist_sff_proc_fops = {
 449        .owner          = THIS_MODULE,
 450        .open           = can_rcvlist_sff_proc_open,
 451        .read           = seq_read,
 452        .llseek         = seq_lseek,
 453        .release        = single_release,
 454};
 455
 456/*
 457 * proc utility functions
 458 */
 459
 460static void can_remove_proc_readentry(const char *name)
 461{
 462        if (can_dir)
 463                remove_proc_entry(name, can_dir);
 464}
 465
 466/*
 467 * can_init_proc - create main CAN proc directory and procfs entries
 468 */
 469void can_init_proc(void)
 470{
 471        /* create /proc/net/can directory */
 472        can_dir = proc_mkdir("can", init_net.proc_net);
 473
 474        if (!can_dir) {
 475                printk(KERN_INFO "can: failed to create /proc/net/can . "
 476                       "CONFIG_PROC_FS missing?\n");
 477                return;
 478        }
 479
 480        /* own procfs entries from the AF_CAN core */
 481        pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
 482                                      &can_version_proc_fops);
 483        pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
 484                                      &can_stats_proc_fops);
 485        pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
 486                                      &can_reset_stats_proc_fops);
 487        pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
 488                                           &can_rcvlist_proc_fops, (void *)RX_ERR);
 489        pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
 490                                           &can_rcvlist_proc_fops, (void *)RX_ALL);
 491        pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
 492                                           &can_rcvlist_proc_fops, (void *)RX_FIL);
 493        pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
 494                                           &can_rcvlist_proc_fops, (void *)RX_INV);
 495        pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
 496                                           &can_rcvlist_proc_fops, (void *)RX_EFF);
 497        pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
 498                                      &can_rcvlist_sff_proc_fops);
 499}
 500
 501/*
 502 * can_remove_proc - remove procfs entries and main CAN proc directory
 503 */
 504void can_remove_proc(void)
 505{
 506        if (pde_version)
 507                can_remove_proc_readentry(CAN_PROC_VERSION);
 508
 509        if (pde_stats)
 510                can_remove_proc_readentry(CAN_PROC_STATS);
 511
 512        if (pde_reset_stats)
 513                can_remove_proc_readentry(CAN_PROC_RESET_STATS);
 514
 515        if (pde_rcvlist_err)
 516                can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
 517
 518        if (pde_rcvlist_all)
 519                can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
 520
 521        if (pde_rcvlist_fil)
 522                can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
 523
 524        if (pde_rcvlist_inv)
 525                can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
 526
 527        if (pde_rcvlist_eff)
 528                can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
 529
 530        if (pde_rcvlist_sff)
 531                can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
 532
 533        if (can_dir)
 534                proc_net_remove(&init_net, "can");
 535}
 536
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.