net/can/proc.c - kernel/msm-4.9 - Gitiles

 /*
  * proc.c - procfs support for Protocol family CAN core module
  *
  * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. Neither the name of Volkswagen nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * Alternatively, provided that this notice is retained in full, this
  * software may be distributed under the terms of the GNU General
  * Public License ("GPL") version 2, in which case the provisions of the
  * GPL apply INSTEAD OF those given above.
  *
  * The provided data structures and external interfaces from this code
  * are not restricted to be used by modules with a GPL compatible license.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
  */

 #include <linux/module.h>
 #include <linux/proc_fs.h>
 #include <linux/list.h>
 #include <linux/rcupdate.h>
 #include <linux/if_arp.h>
 #include <linux/can/core.h>

 #include "af_can.h"

 /*
  * proc filenames for the PF_CAN core
  */

 #define CAN_PROC_VERSION     "version"
 #define CAN_PROC_STATS       "stats"
 #define CAN_PROC_RESET_STATS "reset_stats"
 #define CAN_PROC_RCVLIST_ALL "rcvlist_all"
 #define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
 #define CAN_PROC_RCVLIST_INV "rcvlist_inv"
 #define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
 #define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
 #define CAN_PROC_RCVLIST_ERR "rcvlist_err"

 static struct proc_dir_entry *can_dir;
 static struct proc_dir_entry *pde_version;
 static struct proc_dir_entry *pde_stats;
 static struct proc_dir_entry *pde_reset_stats;
 static struct proc_dir_entry *pde_rcvlist_all;
 static struct proc_dir_entry *pde_rcvlist_fil;
 static struct proc_dir_entry *pde_rcvlist_inv;
 static struct proc_dir_entry *pde_rcvlist_sff;
 static struct proc_dir_entry *pde_rcvlist_eff;
 static struct proc_dir_entry *pde_rcvlist_err;

 static int user_reset;

 static const char rx_list_name[][8] = {
 	[RX_ERR] = "rx_err",
 	[RX_ALL] = "rx_all",
 	[RX_FIL] = "rx_fil",
 	[RX_INV] = "rx_inv",
 	[RX_EFF] = "rx_eff",
 };

 /*
  * af_can statistics stuff
  */

 static void can_init_stats(void)
 {
 	/*
 	 * This memset function is called from a timer context (when
 	 * can_stattimer is active which is the default) OR in a process
 	 * context (reading the proc_fs when can_stattimer is disabled).
 	 */
 	memset(&can_stats, 0, sizeof(can_stats));
 	can_stats.jiffies_init = jiffies;

 	can_pstats.stats_reset++;

 	if (user_reset) {
 		user_reset = 0;
 		can_pstats.user_reset++;
 	}
 }

 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 			       unsigned long count)
 {
 	unsigned long rate;

 	if (oldjif == newjif)
 		return 0;

 	/* see can_stat_update() - this should NEVER happen! */
 	if (count > (ULONG_MAX / HZ)) {
 		printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
 		       count);
 		return 99999999;
 	}

 	rate = (count * HZ) / (newjif - oldjif);

 	return rate;
 }

 void can_stat_update(unsigned long data)
 {
 	unsigned long j = jiffies; /* snapshot */

 	/* restart counting in timer context on user request */
 	if (user_reset)
 		can_init_stats();

 	/* restart counting on jiffies overflow */
 	if (j < can_stats.jiffies_init)
 		can_init_stats();

 	/* prevent overflow in calc_rate() */
 	if (can_stats.rx_frames > (ULONG_MAX / HZ))
 		can_init_stats();

 	/* prevent overflow in calc_rate() */
 	if (can_stats.tx_frames > (ULONG_MAX / HZ))
 		can_init_stats();

 	/* matches overflow - very improbable */
 	if (can_stats.matches > (ULONG_MAX / 100))
 		can_init_stats();

 	/* calc total values */
 	if (can_stats.rx_frames)
 		can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
 			can_stats.rx_frames;

 	can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
 					    can_stats.tx_frames);
 	can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
 					    can_stats.rx_frames);

 	/* calc current values */
 	if (can_stats.rx_frames_delta)
 		can_stats.current_rx_match_ratio =
 			(can_stats.matches_delta * 100) /
 			can_stats.rx_frames_delta;

 	can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
 	can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);

 	/* check / update maximum values */
 	if (can_stats.max_tx_rate < can_stats.current_tx_rate)
 		can_stats.max_tx_rate = can_stats.current_tx_rate;

 	if (can_stats.max_rx_rate < can_stats.current_rx_rate)
 		can_stats.max_rx_rate = can_stats.current_rx_rate;

 	if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
 		can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;

 	/* clear values for 'current rate' calculation */
 	can_stats.tx_frames_delta = 0;
 	can_stats.rx_frames_delta = 0;
 	can_stats.matches_delta   = 0;

 	/* restart timer (one second) */
 	mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
 }

 /*
  * proc read functions
  */

 static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list,
 			      struct net_device *dev)
 {
 	struct receiver *r;
 	struct hlist_node *n;

 	hlist_for_each_entry_rcu(r, n, rx_list, list) {
 		char *fmt = (r->can_id & CAN_EFF_FLAG)?
 			"   %-5s  %08x  %08x  %pK  %pK  %8ld  %s\n" :
 			"   %-5s     %03x    %08x  %pK  %pK  %8ld  %s\n";

 		seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
 				r->func, r->data, r->matches, r->ident);
 	}
 }

 static void can_print_recv_banner(struct seq_file *m)
 {
 	/*
 	 *                  can1.  00000000  00000000  00000000
 	 *                 .......          0  tp20
 	 */
 	seq_puts(m, "  device   can_id   can_mask  function"
 			"  userdata   matches  ident\n");
 }

 static int can_stats_proc_show(struct seq_file *m, void *v)
 {
 	seq_putc(m, '\n');
 	seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
 	seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
 	seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);

 	seq_putc(m, '\n');

 	if (can_stattimer.function == can_stat_update) {
 		seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
 				can_stats.total_rx_match_ratio);

 		seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
 				can_stats.total_tx_rate);
 		seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
 				can_stats.total_rx_rate);

 		seq_putc(m, '\n');

 		seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
 				can_stats.current_rx_match_ratio);

 		seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
 				can_stats.current_tx_rate);
 		seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
 				can_stats.current_rx_rate);

 		seq_putc(m, '\n');

 		seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
 				can_stats.max_rx_match_ratio);

 		seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
 				can_stats.max_tx_rate);
 		seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
 				can_stats.max_rx_rate);

 		seq_putc(m, '\n');
 	}

 	seq_printf(m, " %8ld current receive list entries (CRCV)\n",
 			can_pstats.rcv_entries);
 	seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
 			can_pstats.rcv_entries_max);

 	if (can_pstats.stats_reset)
 		seq_printf(m, "\n %8ld statistic resets (STR)\n",
 				can_pstats.stats_reset);

 	if (can_pstats.user_reset)
 		seq_printf(m, " %8ld user statistic resets (USTR)\n",
 				can_pstats.user_reset);

 	seq_putc(m, '\n');
 	return 0;
 }

 static int can_stats_proc_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, can_stats_proc_show, NULL);
 }

 static const struct file_operations can_stats_proc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= can_stats_proc_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static int can_reset_stats_proc_show(struct seq_file *m, void *v)
 {
 	user_reset = 1;

 	if (can_stattimer.function == can_stat_update) {
 		seq_printf(m, "Scheduled statistic reset #%ld.\n",
 				can_pstats.stats_reset + 1);

 	} else {
 		if (can_stats.jiffies_init != jiffies)
 			can_init_stats();

 		seq_printf(m, "Performed statistic reset #%ld.\n",
 				can_pstats.stats_reset);
 	}
 	return 0;
 }

 static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, can_reset_stats_proc_show, NULL);
 }

 static const struct file_operations can_reset_stats_proc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= can_reset_stats_proc_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static int can_version_proc_show(struct seq_file *m, void *v)
 {
 	seq_printf(m, "%s\n", CAN_VERSION_STRING);
 	return 0;
 }

 static int can_version_proc_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, can_version_proc_show, NULL);
 }

 static const struct file_operations can_version_proc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= can_version_proc_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
 					     struct net_device *dev,
 					     struct dev_rcv_lists *d)
 {
 	if (!hlist_empty(&d->rx[idx])) {
 		can_print_recv_banner(m);
 		can_print_rcvlist(m, &d->rx[idx], dev);
 	} else
 		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));

 }

 static int can_rcvlist_proc_show(struct seq_file *m, void *v)
 {
 	/* double cast to prevent GCC warning */
 	int idx = (int)(long)m->private;
 	struct net_device *dev;
 	struct dev_rcv_lists *d;

 	seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);

 	rcu_read_lock();

 	/* receive list for 'all' CAN devices (dev == NULL) */
 	d = &can_rx_alldev_list;
 	can_rcvlist_proc_show_one(m, idx, NULL, d);

 	/* receive list for registered CAN devices */
 	for_each_netdev_rcu(&init_net, dev) {
 		if (dev->type == ARPHRD_CAN && dev->ml_priv)
 			can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
 	}

 	rcu_read_unlock();

 	seq_putc(m, '\n');
 	return 0;
 }

 static int can_rcvlist_proc_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
 }

 static const struct file_operations can_rcvlist_proc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= can_rcvlist_proc_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
 						 struct net_device *dev,
 						 struct dev_rcv_lists *d)
 {
 	int i;
 	int all_empty = 1;

 	/* check whether at least one list is non-empty */
 	for (i = 0; i < 0x800; i++)
 		if (!hlist_empty(&d->rx_sff[i])) {
 			all_empty = 0;
 			break;
 		}

 	if (!all_empty) {
 		can_print_recv_banner(m);
 		for (i = 0; i < 0x800; i++) {
 			if (!hlist_empty(&d->rx_sff[i]))
 				can_print_rcvlist(m, &d->rx_sff[i], dev);
 		}
 	} else
 		seq_printf(m, "  (%s: no entry)\n", DNAME(dev));
 }

 static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
 {
 	struct net_device *dev;
 	struct dev_rcv_lists *d;

 	/* RX_SFF */
 	seq_puts(m, "\nreceive list 'rx_sff':\n");

 	rcu_read_lock();

 	/* sff receive list for 'all' CAN devices (dev == NULL) */
 	d = &can_rx_alldev_list;
 	can_rcvlist_sff_proc_show_one(m, NULL, d);

 	/* sff receive list for registered CAN devices */
 	for_each_netdev_rcu(&init_net, dev) {
 		if (dev->type == ARPHRD_CAN && dev->ml_priv)
 			can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
 	}

 	rcu_read_unlock();

 	seq_putc(m, '\n');
 	return 0;
 }

 static int can_rcvlist_sff_proc_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, can_rcvlist_sff_proc_show, NULL);
 }

 static const struct file_operations can_rcvlist_sff_proc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= can_rcvlist_sff_proc_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 /*
  * proc utility functions
  */

 static void can_remove_proc_readentry(const char *name)
 {
 	if (can_dir)
 		remove_proc_entry(name, can_dir);
 }

 /*
  * can_init_proc - create main CAN proc directory and procfs entries
  */
 void can_init_proc(void)
 {
 	/* create /proc/net/can directory */
 	can_dir = proc_mkdir("can", init_net.proc_net);

 	if (!can_dir) {
 		printk(KERN_INFO "can: failed to create /proc/net/can . "
 		       "CONFIG_PROC_FS missing?\n");
 		return;
 	}

 	/* own procfs entries from the AF_CAN core */
 	pde_version     = proc_create(CAN_PROC_VERSION, 0644, can_dir,
 				      &can_version_proc_fops);
 	pde_stats       = proc_create(CAN_PROC_STATS, 0644, can_dir,
 				      &can_stats_proc_fops);
 	pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
 				      &can_reset_stats_proc_fops);
 	pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
 					   &can_rcvlist_proc_fops, (void *)RX_ERR);
 	pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
 					   &can_rcvlist_proc_fops, (void *)RX_ALL);
 	pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
 					   &can_rcvlist_proc_fops, (void *)RX_FIL);
 	pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
 					   &can_rcvlist_proc_fops, (void *)RX_INV);
 	pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
 					   &can_rcvlist_proc_fops, (void *)RX_EFF);
 	pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
 				      &can_rcvlist_sff_proc_fops);
 }

 /*
  * can_remove_proc - remove procfs entries and main CAN proc directory
  */
 void can_remove_proc(void)
 {
 	if (pde_version)
 		can_remove_proc_readentry(CAN_PROC_VERSION);

 	if (pde_stats)
 		can_remove_proc_readentry(CAN_PROC_STATS);

 	if (pde_reset_stats)
 		can_remove_proc_readentry(CAN_PROC_RESET_STATS);

 	if (pde_rcvlist_err)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);

 	if (pde_rcvlist_all)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);

 	if (pde_rcvlist_fil)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);

 	if (pde_rcvlist_inv)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);

 	if (pde_rcvlist_eff)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);

 	if (pde_rcvlist_sff)
 		can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);

 	if (can_dir)
 		proc_net_remove(&init_net, "can");
 }
	/*
	* proc.c - procfs support for Protocol family CAN core module
	*
	* Copyright (c) 2002-2007 Volkswagen Group Electronic Research
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of Volkswagen nor the names of its contributors
	* may be used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* Alternatively, provided that this notice is retained in full, this
	* software may be distributed under the terms of the GNU General
	* Public License ("GPL") version 2, in which case the provisions of the
	* GPL apply INSTEAD OF those given above.
	*
	* The provided data structures and external interfaces from this code
	* are not restricted to be used by modules with a GPL compatible license.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
	* DAMAGE.
	*
	*/

	#include <linux/module.h>
	#include <linux/proc_fs.h>
	#include <linux/list.h>
	#include <linux/rcupdate.h>
	#include <linux/if_arp.h>
	#include <linux/can/core.h>

	#include "af_can.h"

	/*
	* proc filenames for the PF_CAN core
	*/

	#define CAN_PROC_VERSION "version"
	#define CAN_PROC_STATS "stats"
	#define CAN_PROC_RESET_STATS "reset_stats"
	#define CAN_PROC_RCVLIST_ALL "rcvlist_all"
	#define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
	#define CAN_PROC_RCVLIST_INV "rcvlist_inv"
	#define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
	#define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
	#define CAN_PROC_RCVLIST_ERR "rcvlist_err"

	static struct proc_dir_entry *can_dir;
	static struct proc_dir_entry *pde_version;
	static struct proc_dir_entry *pde_stats;
	static struct proc_dir_entry *pde_reset_stats;
	static struct proc_dir_entry *pde_rcvlist_all;
	static struct proc_dir_entry *pde_rcvlist_fil;
	static struct proc_dir_entry *pde_rcvlist_inv;
	static struct proc_dir_entry *pde_rcvlist_sff;
	static struct proc_dir_entry *pde_rcvlist_eff;
	static struct proc_dir_entry *pde_rcvlist_err;

	static int user_reset;

	static const char rx_list_name[][8] = {
	[RX_ERR] = "rx_err",
	[RX_ALL] = "rx_all",
	[RX_FIL] = "rx_fil",
	[RX_INV] = "rx_inv",
	[RX_EFF] = "rx_eff",
	};

	/*
	* af_can statistics stuff
	*/

	static void can_init_stats(void)
	{
	/*
	* This memset function is called from a timer context (when
	* can_stattimer is active which is the default) OR in a process
	* context (reading the proc_fs when can_stattimer is disabled).
	*/
	memset(&can_stats, 0, sizeof(can_stats));
	can_stats.jiffies_init = jiffies;

	can_pstats.stats_reset++;

	if (user_reset) {
	user_reset = 0;
	can_pstats.user_reset++;
	}
	}

	static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
	unsigned long count)
	{
	unsigned long rate;

	if (oldjif == newjif)
	return 0;

	/* see can_stat_update() - this should NEVER happen! */
	if (count > (ULONG_MAX / HZ)) {
	printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
	count);
	return 99999999;
	}

	rate = (count * HZ) / (newjif - oldjif);

	return rate;
	}

	void can_stat_update(unsigned long data)
	{
	unsigned long j = jiffies; /* snapshot */

	/* restart counting in timer context on user request */
	if (user_reset)
	can_init_stats();

	/* restart counting on jiffies overflow */
	if (j < can_stats.jiffies_init)
	can_init_stats();

	/* prevent overflow in calc_rate() */
	if (can_stats.rx_frames > (ULONG_MAX / HZ))
	can_init_stats();

	/* prevent overflow in calc_rate() */
	if (can_stats.tx_frames > (ULONG_MAX / HZ))
	can_init_stats();

	/* matches overflow - very improbable */
	if (can_stats.matches > (ULONG_MAX / 100))
	can_init_stats();

	/* calc total values */
	if (can_stats.rx_frames)
	can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
	can_stats.rx_frames;

	can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
	can_stats.tx_frames);
	can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
	can_stats.rx_frames);

	/* calc current values */
	if (can_stats.rx_frames_delta)
	can_stats.current_rx_match_ratio =
	(can_stats.matches_delta * 100) /
	can_stats.rx_frames_delta;

	can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
	can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);

	/* check / update maximum values */
	if (can_stats.max_tx_rate < can_stats.current_tx_rate)
	can_stats.max_tx_rate = can_stats.current_tx_rate;

	if (can_stats.max_rx_rate < can_stats.current_rx_rate)
	can_stats.max_rx_rate = can_stats.current_rx_rate;

	if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
	can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;

	/* clear values for 'current rate' calculation */
	can_stats.tx_frames_delta = 0;
	can_stats.rx_frames_delta = 0;
	can_stats.matches_delta = 0;

	/* restart timer (one second) */
	mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
	}

	/*
	* proc read functions
	*/

	static void can_print_rcvlist(struct seq_file m, struct hlist_head rx_list,
	struct net_device *dev)
	{
	struct receiver *r;
	struct hlist_node *n;

	hlist_for_each_entry_rcu(r, n, rx_list, list) {
	char *fmt = (r->can_id & CAN_EFF_FLAG)?
	" %-5s %08x %08x %pK %pK %8ld %s\n" :
	" %-5s %03x %08x %pK %pK %8ld %s\n";

	seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask,
	r->func, r->data, r->matches, r->ident);
	}
	}

	static void can_print_recv_banner(struct seq_file *m)
	{
	/*
	* can1. 00000000 00000000 00000000
	* ....... 0 tp20
	*/
	seq_puts(m, " device can_id can_mask function"
	" userdata matches ident\n");
	}

	static int can_stats_proc_show(struct seq_file m, void v)
	{
	seq_putc(m, '\n');
	seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames);
	seq_printf(m, " %8ld received frames (RXF)\n", can_stats.rx_frames);
	seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches);

	seq_putc(m, '\n');

	if (can_stattimer.function == can_stat_update) {
	seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
	can_stats.total_rx_match_ratio);

	seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
	can_stats.total_tx_rate);
	seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
	can_stats.total_rx_rate);

	seq_putc(m, '\n');

	seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
	can_stats.current_rx_match_ratio);

	seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
	can_stats.current_tx_rate);
	seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
	can_stats.current_rx_rate);

	seq_putc(m, '\n');

	seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
	can_stats.max_rx_match_ratio);

	seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
	can_stats.max_tx_rate);
	seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
	can_stats.max_rx_rate);

	seq_putc(m, '\n');
	}

	seq_printf(m, " %8ld current receive list entries (CRCV)\n",
	can_pstats.rcv_entries);
	seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
	can_pstats.rcv_entries_max);

	if (can_pstats.stats_reset)
	seq_printf(m, "\n %8ld statistic resets (STR)\n",
	can_pstats.stats_reset);

	if (can_pstats.user_reset)
	seq_printf(m, " %8ld user statistic resets (USTR)\n",
	can_pstats.user_reset);

	seq_putc(m, '\n');
	return 0;
	}

	static int can_stats_proc_open(struct inode inode, struct file file)
	{
	return single_open(file, can_stats_proc_show, NULL);
	}

	static const struct file_operations can_stats_proc_fops = {
	.owner = THIS_MODULE,
	.open = can_stats_proc_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static int can_reset_stats_proc_show(struct seq_file m, void v)
	{
	user_reset = 1;

	if (can_stattimer.function == can_stat_update) {
	seq_printf(m, "Scheduled statistic reset #%ld.\n",
	can_pstats.stats_reset + 1);

	} else {
	if (can_stats.jiffies_init != jiffies)
	can_init_stats();

	seq_printf(m, "Performed statistic reset #%ld.\n",
	can_pstats.stats_reset);
	}
	return 0;
	}

	static int can_reset_stats_proc_open(struct inode inode, struct file file)
	{
	return single_open(file, can_reset_stats_proc_show, NULL);
	}

	static const struct file_operations can_reset_stats_proc_fops = {
	.owner = THIS_MODULE,
	.open = can_reset_stats_proc_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static int can_version_proc_show(struct seq_file m, void v)
	{
	seq_printf(m, "%s\n", CAN_VERSION_STRING);
	return 0;
	}

	static int can_version_proc_open(struct inode inode, struct file file)
	{
	return single_open(file, can_version_proc_show, NULL);
	}

	static const struct file_operations can_version_proc_fops = {
	.owner = THIS_MODULE,
	.open = can_version_proc_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx,
	struct net_device *dev,
	struct dev_rcv_lists *d)
	{
	if (!hlist_empty(&d->rx[idx])) {
	can_print_recv_banner(m);
	can_print_rcvlist(m, &d->rx[idx], dev);
	} else
	seq_printf(m, " (%s: no entry)\n", DNAME(dev));

	}

	static int can_rcvlist_proc_show(struct seq_file m, void v)
	{
	/* double cast to prevent GCC warning */
	int idx = (int)(long)m->private;
	struct net_device *dev;
	struct dev_rcv_lists *d;

	seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]);

	rcu_read_lock();

	/* receive list for 'all' CAN devices (dev == NULL) */
	d = &can_rx_alldev_list;
	can_rcvlist_proc_show_one(m, idx, NULL, d);

	/* receive list for registered CAN devices */
	for_each_netdev_rcu(&init_net, dev) {
	if (dev->type == ARPHRD_CAN && dev->ml_priv)
	can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
	}

	rcu_read_unlock();

	seq_putc(m, '\n');
	return 0;
	}

	static int can_rcvlist_proc_open(struct inode inode, struct file file)
	{
	return single_open(file, can_rcvlist_proc_show, PDE(inode)->data);
	}

	static const struct file_operations can_rcvlist_proc_fops = {
	.owner = THIS_MODULE,
	.open = can_rcvlist_proc_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static inline void can_rcvlist_sff_proc_show_one(struct seq_file *m,
	struct net_device *dev,
	struct dev_rcv_lists *d)
	{
	int i;
	int all_empty = 1;

	/* check whether at least one list is non-empty */
	for (i = 0; i < 0x800; i++)
	if (!hlist_empty(&d->rx_sff[i])) {
	all_empty = 0;
	break;
	}

	if (!all_empty) {
	can_print_recv_banner(m);
	for (i = 0; i < 0x800; i++) {
	if (!hlist_empty(&d->rx_sff[i]))
	can_print_rcvlist(m, &d->rx_sff[i], dev);
	}
	} else
	seq_printf(m, " (%s: no entry)\n", DNAME(dev));
	}

	static int can_rcvlist_sff_proc_show(struct seq_file m, void v)
	{
	struct net_device *dev;
	struct dev_rcv_lists *d;

	/* RX_SFF */
	seq_puts(m, "\nreceive list 'rx_sff':\n");

	rcu_read_lock();

	/* sff receive list for 'all' CAN devices (dev == NULL) */
	d = &can_rx_alldev_list;
	can_rcvlist_sff_proc_show_one(m, NULL, d);

	/* sff receive list for registered CAN devices */
	for_each_netdev_rcu(&init_net, dev) {
	if (dev->type == ARPHRD_CAN && dev->ml_priv)
	can_rcvlist_sff_proc_show_one(m, dev, dev->ml_priv);
	}

	rcu_read_unlock();

	seq_putc(m, '\n');
	return 0;
	}

	static int can_rcvlist_sff_proc_open(struct inode inode, struct file file)
	{
	return single_open(file, can_rcvlist_sff_proc_show, NULL);
	}

	static const struct file_operations can_rcvlist_sff_proc_fops = {
	.owner = THIS_MODULE,
	.open = can_rcvlist_sff_proc_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	/*
	* proc utility functions
	*/

	static void can_remove_proc_readentry(const char *name)
	{
	if (can_dir)
	remove_proc_entry(name, can_dir);
	}

	/*
	* can_init_proc - create main CAN proc directory and procfs entries
	*/
	void can_init_proc(void)
	{
	/* create /proc/net/can directory */
	can_dir = proc_mkdir("can", init_net.proc_net);

	if (!can_dir) {
	printk(KERN_INFO "can: failed to create /proc/net/can . "
	"CONFIG_PROC_FS missing?\n");
	return;
	}

	/* own procfs entries from the AF_CAN core */
	pde_version = proc_create(CAN_PROC_VERSION, 0644, can_dir,
	&can_version_proc_fops);
	pde_stats = proc_create(CAN_PROC_STATS, 0644, can_dir,
	&can_stats_proc_fops);
	pde_reset_stats = proc_create(CAN_PROC_RESET_STATS, 0644, can_dir,
	&can_reset_stats_proc_fops);
	pde_rcvlist_err = proc_create_data(CAN_PROC_RCVLIST_ERR, 0644, can_dir,
	&can_rcvlist_proc_fops, (void *)RX_ERR);
	pde_rcvlist_all = proc_create_data(CAN_PROC_RCVLIST_ALL, 0644, can_dir,
	&can_rcvlist_proc_fops, (void *)RX_ALL);
	pde_rcvlist_fil = proc_create_data(CAN_PROC_RCVLIST_FIL, 0644, can_dir,
	&can_rcvlist_proc_fops, (void *)RX_FIL);
	pde_rcvlist_inv = proc_create_data(CAN_PROC_RCVLIST_INV, 0644, can_dir,
	&can_rcvlist_proc_fops, (void *)RX_INV);
	pde_rcvlist_eff = proc_create_data(CAN_PROC_RCVLIST_EFF, 0644, can_dir,
	&can_rcvlist_proc_fops, (void *)RX_EFF);
	pde_rcvlist_sff = proc_create(CAN_PROC_RCVLIST_SFF, 0644, can_dir,
	&can_rcvlist_sff_proc_fops);
	}

	/*
	* can_remove_proc - remove procfs entries and main CAN proc directory
	*/
	void can_remove_proc(void)
	{
	if (pde_version)
	can_remove_proc_readentry(CAN_PROC_VERSION);

	if (pde_stats)
	can_remove_proc_readentry(CAN_PROC_STATS);

	if (pde_reset_stats)
	can_remove_proc_readentry(CAN_PROC_RESET_STATS);

	if (pde_rcvlist_err)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);

	if (pde_rcvlist_all)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);

	if (pde_rcvlist_fil)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);

	if (pde_rcvlist_inv)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);

	if (pde_rcvlist_eff)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);

	if (pde_rcvlist_sff)
	can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);

	if (can_dir)
	proc_net_remove(&init_net, "can");
	}