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can: complete initial namespace support

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The statistics and its proc output was not implemented as per-net in the
initial network namespace support by Mario Kicherer (8e8cda6d73).
This patch adds the missing per-net statistics for the CAN subsystem.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Oliver Hartkopp 2017-04-25 08:19:41 +02:00 committed by Marc Kleine-Budde
parent f2e72f43e7
commit cb5635a367
5 changed files with 121 additions and 105 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

4
include/linux/can/core.h
View file

@ -5,7 +5,7 @@
* *
* Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> * Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
* Urs Thuermann <urs.thuermann@volkswagen.de> * Urs Thuermann <urs.thuermann@volkswagen.de>
* Copyright (c) 2002-2007 Volkswagen Group Electronic Research * Copyright (c) 2002-2017 Volkswagen Group Electronic Research
* All rights reserved. * All rights reserved.
* *
*/ */
@ -17,7 +17,7 @@
#include <linux/skbuff.h> #include <linux/skbuff.h>
#include <linux/netdevice.h> #include <linux/netdevice.h>
#define CAN_VERSION "20120528" #define CAN_VERSION "20170425"
/* increment this number each time you change some user-space interface */ /* increment this number each time you change some user-space interface */
#define CAN_ABI_VERSION "9" #define CAN_ABI_VERSION "9"

5
include/net/netns/can.h
View file

@ -8,6 +8,8 @@
#include <linux/spinlock.h> #include <linux/spinlock.h>
struct dev_rcv_lists; struct dev_rcv_lists;
struct s_stats;
struct s_pstats;
struct netns_can { struct netns_can {
#if IS_ENABLED(CONFIG_PROC_FS) #if IS_ENABLED(CONFIG_PROC_FS)
@ -26,6 +28,9 @@ struct netns_can {
/* receive filters subscribed for 'all' CAN devices */ /* receive filters subscribed for 'all' CAN devices */
struct dev_rcv_lists *can_rx_alldev_list; struct dev_rcv_lists *can_rx_alldev_list;
spinlock_t can_rcvlists_lock; spinlock_t can_rcvlists_lock;
struct timer_list can_stattimer;/* timer for statistics update */
struct s_stats *can_stats; /* packet statistics */
struct s_pstats *can_pstats; /* receive list statistics */
}; };
#endif /* __NETNS_CAN_H__ */ #endif /* __NETNS_CAN_H__ */

71
net/can/af_can.c
View file

@ -2,7 +2,7 @@
* af_can.c - Protocol family CAN core module * af_can.c - Protocol family CAN core module
* (used by different CAN protocol modules) * (used by different CAN protocol modules)
* *
* Copyright (c) 2002-2007 Volkswagen Group Electronic Research * Copyright (c) 2002-2017 Volkswagen Group Electronic Research
* All rights reserved. * All rights reserved.
* *
* Redistribution and use in source and binary forms, with or without * Redistribution and use in source and binary forms, with or without
@ -81,10 +81,6 @@ static struct kmem_cache *rcv_cache __read_mostly;
static const struct can_proto *proto_tab[CAN_NPROTO] __read_mostly; static const struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
static DEFINE_MUTEX(proto_tab_lock); static DEFINE_MUTEX(proto_tab_lock);
struct timer_list can_stattimer; /* timer for statistics update */
struct s_stats can_stats; /* packet statistics */
struct s_pstats can_pstats; /* receive list statistics */
static atomic_t skbcounter = ATOMIC_INIT(0); static atomic_t skbcounter = ATOMIC_INIT(0);
/* /*
@ -221,6 +217,7 @@ int can_send(struct sk_buff *skb, int loop)
{ {
struct sk_buff *newskb = NULL; struct sk_buff *newskb = NULL;
struct canfd_frame *cfd = (struct canfd_frame *)skb->data; struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
struct s_stats *can_stats = dev_net(skb->dev)->can.can_stats;
int err = -EINVAL; int err = -EINVAL;
if (skb->len == CAN_MTU) { if (skb->len == CAN_MTU) {
@ -309,8 +306,8 @@ int can_send(struct sk_buff *skb, int loop)
netif_rx_ni(newskb); netif_rx_ni(newskb);
/* update statistics */ /* update statistics */
can_stats.tx_frames++; can_stats->tx_frames++;
can_stats.tx_frames_delta++; can_stats->tx_frames_delta++;
return 0; return 0;
@ -468,6 +465,7 @@ int can_rx_register(struct net *net, struct net_device *dev, canid_t can_id,
struct receiver *r; struct receiver *r;
struct hlist_head *rl; struct hlist_head *rl;
struct dev_rcv_lists *d; struct dev_rcv_lists *d;
struct s_pstats *can_pstats = net->can.can_pstats;
int err = 0; int err = 0;
/* insert new receiver (dev,canid,mask) -> (func,data) */ /* insert new receiver (dev,canid,mask) -> (func,data) */
@ -499,9 +497,9 @@ int can_rx_register(struct net *net, struct net_device *dev, canid_t can_id,
hlist_add_head_rcu(&r->list, rl); hlist_add_head_rcu(&r->list, rl);
d->entries++; d->entries++;
can_pstats.rcv_entries++; can_pstats->rcv_entries++;
if (can_pstats.rcv_entries_max < can_pstats.rcv_entries) if (can_pstats->rcv_entries_max < can_pstats->rcv_entries)
can_pstats.rcv_entries_max = can_pstats.rcv_entries; can_pstats->rcv_entries_max = can_pstats->rcv_entries;
} else { } else {
kmem_cache_free(rcv_cache, r); kmem_cache_free(rcv_cache, r);
err = -ENODEV; err = -ENODEV;
@ -543,6 +541,7 @@ void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id,
{ {
struct receiver *r = NULL; struct receiver *r = NULL;
struct hlist_head *rl; struct hlist_head *rl;
struct s_pstats *can_pstats = net->can.can_pstats;
struct dev_rcv_lists *d; struct dev_rcv_lists *d;
if (dev && dev->type != ARPHRD_CAN) if (dev && dev->type != ARPHRD_CAN)
@ -589,8 +588,8 @@ void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id,
hlist_del_rcu(&r->list); hlist_del_rcu(&r->list);
d->entries--; d->entries--;
if (can_pstats.rcv_entries > 0) if (can_pstats->rcv_entries > 0)
can_pstats.rcv_entries--; can_pstats->rcv_entries--;
/* remove device structure requested by NETDEV_UNREGISTER */ /* remove device structure requested by NETDEV_UNREGISTER */
if (d->remove_on_zero_entries && !d->entries) { if (d->remove_on_zero_entries && !d->entries) {
@ -684,11 +683,13 @@ static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
static void can_receive(struct sk_buff *skb, struct net_device *dev) static void can_receive(struct sk_buff *skb, struct net_device *dev)
{ {
struct dev_rcv_lists *d; struct dev_rcv_lists *d;
struct net *net = dev_net(dev);
struct s_stats *can_stats = net->can.can_stats;
int matches; int matches;
/* update statistics */ /* update statistics */
can_stats.rx_frames++; can_stats->rx_frames++;
can_stats.rx_frames_delta++; can_stats->rx_frames_delta++;
/* create non-zero unique skb identifier together with *skb */ /* create non-zero unique skb identifier together with *skb */
while (!(can_skb_prv(skb)->skbcnt)) while (!(can_skb_prv(skb)->skbcnt))
@ -697,10 +698,10 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev)
rcu_read_lock(); rcu_read_lock();
/* deliver the packet to sockets listening on all devices */ /* deliver the packet to sockets listening on all devices */
matches = can_rcv_filter(dev_net(dev)->can.can_rx_alldev_list, skb); matches = can_rcv_filter(net->can.can_rx_alldev_list, skb);
/* find receive list for this device */ /* find receive list for this device */
d = find_dev_rcv_lists(dev_net(dev), dev); d = find_dev_rcv_lists(net, dev);
if (d) if (d)
matches += can_rcv_filter(d, skb); matches += can_rcv_filter(d, skb);
@ -710,8 +711,8 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev)
consume_skb(skb); consume_skb(skb);
if (matches > 0) { if (matches > 0) {
can_stats.matches++; can_stats->matches++;
can_stats.matches_delta++; can_stats->matches_delta++;
} }
} }
@ -876,8 +877,20 @@ static int can_pernet_init(struct net *net)
net->can.can_rx_alldev_list = net->can.can_rx_alldev_list =
kzalloc(sizeof(struct dev_rcv_lists), GFP_KERNEL); kzalloc(sizeof(struct dev_rcv_lists), GFP_KERNEL);
if (IS_ENABLED(CONFIG_PROC_FS)) net->can.can_stats = kzalloc(sizeof(struct s_stats), GFP_KERNEL);
net->can.can_pstats = kzalloc(sizeof(struct s_pstats), GFP_KERNEL);
if (IS_ENABLED(CONFIG_PROC_FS)) {
/* the statistics are updated every second (timer triggered) */
if (stats_timer) {
setup_timer(&net->can.can_stattimer, can_stat_update,
(unsigned long)net);
mod_timer(&net->can.can_stattimer,
round_jiffies(jiffies + HZ));
}
net->can.can_stats->jiffies_init = jiffies;
can_init_proc(net); can_init_proc(net);
}
return 0; return 0;
} }
@ -886,8 +899,11 @@ static void can_pernet_exit(struct net *net)
{ {
struct net_device *dev; struct net_device *dev;
if (IS_ENABLED(CONFIG_PROC_FS)) if (IS_ENABLED(CONFIG_PROC_FS)) {
can_remove_proc(net); can_remove_proc(net);
if (stats_timer)
del_timer_sync(&net->can.can_stattimer);
}
/* remove created dev_rcv_lists from still registered CAN devices */ /* remove created dev_rcv_lists from still registered CAN devices */
rcu_read_lock(); rcu_read_lock();
@ -903,6 +919,8 @@ static void can_pernet_exit(struct net *net)
rcu_read_unlock(); rcu_read_unlock();
kfree(net->can.can_rx_alldev_list); kfree(net->can.can_rx_alldev_list);
kfree(net->can.can_stats);
kfree(net->can.can_pstats);
} }
/* /*
@ -950,14 +968,6 @@ static __init int can_init(void)
if (!rcv_cache) if (!rcv_cache)
return -ENOMEM; return -ENOMEM;
if (IS_ENABLED(CONFIG_PROC_FS)) {
if (stats_timer) {
/* the statistics are updated every second (timer triggered) */
setup_timer(&can_stattimer, can_stat_update, 0);
mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
}
}
register_pernet_subsys(&can_pernet_ops); register_pernet_subsys(&can_pernet_ops);
/* protocol register */ /* protocol register */
@ -971,11 +981,6 @@ static __init int can_init(void)
static __exit void can_exit(void) static __exit void can_exit(void)
{ {
if (IS_ENABLED(CONFIG_PROC_FS)) {
if (stats_timer)
del_timer_sync(&can_stattimer);
}
/* protocol unregister */ /* protocol unregister */
dev_remove_pack(&canfd_packet); dev_remove_pack(&canfd_packet);
dev_remove_pack(&can_packet); dev_remove_pack(&can_packet);

5
net/can/af_can.h
View file

@ -115,9 +115,4 @@ void can_init_proc(struct net *net);
void can_remove_proc(struct net *net); void can_remove_proc(struct net *net);
void can_stat_update(unsigned long data); void can_stat_update(unsigned long data);
/* structures and variables from af_can.c needed in proc.c for reading */
extern struct timer_list can_stattimer; /* timer for statistics update */
extern struct s_stats can_stats; /* packet statistics */
extern struct s_pstats can_pstats; /* receive list statistics */
#endif /* AF_CAN_H */ #endif /* AF_CAN_H */

141
net/can/proc.c
View file

@ -75,21 +75,23 @@ static const char rx_list_name[][8] = {
* af_can statistics stuff * af_can statistics stuff
*/ */
static void can_init_stats(void) static void can_init_stats(struct net *net)
{ {
struct s_stats *can_stats = net->can.can_stats;
struct s_pstats *can_pstats = net->can.can_pstats;
/* /*
* This memset function is called from a timer context (when * This memset function is called from a timer context (when
* can_stattimer is active which is the default) OR in a process * can_stattimer is active which is the default) OR in a process
* context (reading the proc_fs when can_stattimer is disabled). * context (reading the proc_fs when can_stattimer is disabled).
*/ */
memset(&can_stats, 0, sizeof(can_stats)); memset(can_stats, 0, sizeof(struct s_stats));
can_stats.jiffies_init = jiffies; can_stats->jiffies_init = jiffies;
can_pstats.stats_reset++; can_pstats->stats_reset++;
if (user_reset) { if (user_reset) {
user_reset = 0; user_reset = 0;
can_pstats.user_reset++; can_pstats->user_reset++;
} }
} }
@ -115,64 +117,66 @@ static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
void can_stat_update(unsigned long data) void can_stat_update(unsigned long data)
{ {
struct net *net = (struct net *)data;
struct s_stats *can_stats = net->can.can_stats;
unsigned long j = jiffies; /* snapshot */ unsigned long j = jiffies; /* snapshot */
/* restart counting in timer context on user request */ /* restart counting in timer context on user request */
if (user_reset) if (user_reset)
can_init_stats(); can_init_stats(net);
/* restart counting on jiffies overflow */ /* restart counting on jiffies overflow */
if (j < can_stats.jiffies_init) if (j < can_stats->jiffies_init)
can_init_stats(); can_init_stats(net);
/* prevent overflow in calc_rate() */ /* prevent overflow in calc_rate() */
if (can_stats.rx_frames > (ULONG_MAX / HZ)) if (can_stats->rx_frames > (ULONG_MAX / HZ))
can_init_stats(); can_init_stats(net);
/* prevent overflow in calc_rate() */ /* prevent overflow in calc_rate() */
if (can_stats.tx_frames > (ULONG_MAX / HZ)) if (can_stats->tx_frames > (ULONG_MAX / HZ))
can_init_stats(); can_init_stats(net);
/* matches overflow - very improbable */ /* matches overflow - very improbable */
if (can_stats.matches > (ULONG_MAX / 100)) if (can_stats->matches > (ULONG_MAX / 100))
can_init_stats(); can_init_stats(net);
/* calc total values */ /* calc total values */
if (can_stats.rx_frames) if (can_stats->rx_frames)
can_stats.total_rx_match_ratio = (can_stats.matches * 100) / can_stats->total_rx_match_ratio = (can_stats->matches * 100) /
can_stats.rx_frames; can_stats->rx_frames;
can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j, can_stats->total_tx_rate = calc_rate(can_stats->jiffies_init, j,
can_stats.tx_frames); can_stats->tx_frames);
can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j, can_stats->total_rx_rate = calc_rate(can_stats->jiffies_init, j,
can_stats.rx_frames); can_stats->rx_frames);
/* calc current values */ /* calc current values */
if (can_stats.rx_frames_delta) if (can_stats->rx_frames_delta)
can_stats.current_rx_match_ratio = can_stats->current_rx_match_ratio =
(can_stats.matches_delta * 100) / (can_stats->matches_delta * 100) /
can_stats.rx_frames_delta; can_stats->rx_frames_delta;
can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_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); can_stats->current_rx_rate = calc_rate(0, HZ, can_stats->rx_frames_delta);
/* check / update maximum values */ /* check / update maximum values */
if (can_stats.max_tx_rate < can_stats.current_tx_rate) if (can_stats->max_tx_rate < can_stats->current_tx_rate)
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) if (can_stats->max_rx_rate < can_stats->current_rx_rate)
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) 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; can_stats->max_rx_match_ratio = can_stats->current_rx_match_ratio;
/* clear values for 'current rate' calculation */ /* clear values for 'current rate' calculation */
can_stats.tx_frames_delta = 0; can_stats->tx_frames_delta = 0;
can_stats.rx_frames_delta = 0; can_stats->rx_frames_delta = 0;
can_stats.matches_delta = 0; can_stats->matches_delta = 0;
/* restart timer (one second) */ /* restart timer (one second) */
mod_timer(&can_stattimer, round_jiffies(jiffies + HZ)); mod_timer(&net->can.can_stattimer, round_jiffies(jiffies + HZ));
} }
/* /*
@ -206,57 +210,61 @@ static void can_print_recv_banner(struct seq_file *m)
static int can_stats_proc_show(struct seq_file *m, void *v) static int can_stats_proc_show(struct seq_file *m, void *v)
{ {
struct net *net = m->private;
struct s_stats *can_stats = net->can.can_stats;
struct s_pstats *can_pstats = net->can.can_pstats;
seq_putc(m, '\n'); seq_putc(m, '\n');
seq_printf(m, " %8ld transmitted frames (TXF)\n", can_stats.tx_frames); 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 received frames (RXF)\n", can_stats->rx_frames);
seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats.matches); seq_printf(m, " %8ld matched frames (RXMF)\n", can_stats->matches);
seq_putc(m, '\n'); seq_putc(m, '\n');
if (can_stattimer.function == can_stat_update) { if (net->can.can_stattimer.function == can_stat_update) {
seq_printf(m, " %8ld %% total match ratio (RXMR)\n", seq_printf(m, " %8ld %% total match ratio (RXMR)\n",
can_stats.total_rx_match_ratio); can_stats->total_rx_match_ratio);
seq_printf(m, " %8ld frames/s total tx rate (TXR)\n", seq_printf(m, " %8ld frames/s total tx rate (TXR)\n",
can_stats.total_tx_rate); can_stats->total_tx_rate);
seq_printf(m, " %8ld frames/s total rx rate (RXR)\n", seq_printf(m, " %8ld frames/s total rx rate (RXR)\n",
can_stats.total_rx_rate); can_stats->total_rx_rate);
seq_putc(m, '\n'); seq_putc(m, '\n');
seq_printf(m, " %8ld %% current match ratio (CRXMR)\n", seq_printf(m, " %8ld %% current match ratio (CRXMR)\n",
can_stats.current_rx_match_ratio); can_stats->current_rx_match_ratio);
seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n", seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n",
can_stats.current_tx_rate); can_stats->current_tx_rate);
seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n", seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n",
can_stats.current_rx_rate); can_stats->current_rx_rate);
seq_putc(m, '\n'); seq_putc(m, '\n');
seq_printf(m, " %8ld %% max match ratio (MRXMR)\n", seq_printf(m, " %8ld %% max match ratio (MRXMR)\n",
can_stats.max_rx_match_ratio); can_stats->max_rx_match_ratio);
seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n", seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n",
can_stats.max_tx_rate); can_stats->max_tx_rate);
seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n", seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n",
can_stats.max_rx_rate); can_stats->max_rx_rate);
seq_putc(m, '\n'); seq_putc(m, '\n');
} }
seq_printf(m, " %8ld current receive list entries (CRCV)\n", seq_printf(m, " %8ld current receive list entries (CRCV)\n",
can_pstats.rcv_entries); can_pstats->rcv_entries);
seq_printf(m, " %8ld maximum receive list entries (MRCV)\n", seq_printf(m, " %8ld maximum receive list entries (MRCV)\n",
can_pstats.rcv_entries_max); can_pstats->rcv_entries_max);
if (can_pstats.stats_reset) if (can_pstats->stats_reset)
seq_printf(m, "\n %8ld statistic resets (STR)\n", seq_printf(m, "\n %8ld statistic resets (STR)\n",
can_pstats.stats_reset); can_pstats->stats_reset);
if (can_pstats.user_reset) if (can_pstats->user_reset)
seq_printf(m, " %8ld user statistic resets (USTR)\n", seq_printf(m, " %8ld user statistic resets (USTR)\n",
can_pstats.user_reset); can_pstats->user_reset);
seq_putc(m, '\n'); seq_putc(m, '\n');
return 0; return 0;
@ -264,7 +272,7 @@ static int can_stats_proc_show(struct seq_file *m, void *v)
static int can_stats_proc_open(struct inode *inode, struct file *file) static int can_stats_proc_open(struct inode *inode, struct file *file)
{ {
return single_open(file, can_stats_proc_show, NULL); return single_open_net(inode, file, can_stats_proc_show);
} }
static const struct file_operations can_stats_proc_fops = { static const struct file_operations can_stats_proc_fops = {
@ -277,25 +285,28 @@ static const struct file_operations can_stats_proc_fops = {
static int can_reset_stats_proc_show(struct seq_file *m, void *v) static int can_reset_stats_proc_show(struct seq_file *m, void *v)
{ {
struct net *net = m->private;
struct s_pstats *can_pstats = net->can.can_pstats;
struct s_stats *can_stats = net->can.can_stats;
user_reset = 1; user_reset = 1;
if (can_stattimer.function == can_stat_update) { if (net->can.can_stattimer.function == can_stat_update) {
seq_printf(m, "Scheduled statistic reset #%ld.\n", seq_printf(m, "Scheduled statistic reset #%ld.\n",
can_pstats.stats_reset + 1); can_pstats->stats_reset + 1);
} else { } else {
if (can_stats.jiffies_init != jiffies) if (can_stats->jiffies_init != jiffies)
can_init_stats(); can_init_stats(net);
seq_printf(m, "Performed statistic reset #%ld.\n", seq_printf(m, "Performed statistic reset #%ld.\n",
can_pstats.stats_reset); can_pstats->stats_reset);
} }
return 0; return 0;
} }
static int can_reset_stats_proc_open(struct inode *inode, struct file *file) static int can_reset_stats_proc_open(struct inode *inode, struct file *file)
{ {
return single_open(file, can_reset_stats_proc_show, NULL); return single_open_net(inode, file, can_reset_stats_proc_show);
} }
static const struct file_operations can_reset_stats_proc_fops = { static const struct file_operations can_reset_stats_proc_fops = {
@ -314,7 +325,7 @@ static int can_version_proc_show(struct seq_file *m, void *v)
static int can_version_proc_open(struct inode *inode, struct file *file) static int can_version_proc_open(struct inode *inode, struct file *file)
{ {
return single_open(file, can_version_proc_show, NULL); return single_open_net(inode, file, can_version_proc_show);
} }
static const struct file_operations can_version_proc_fops = { static const struct file_operations can_version_proc_fops = {