2 * af_can.c - Protocol family CAN core module
3 * (used by different CAN protocol modules)
5 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of Volkswagen nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * Alternatively, provided that this notice is retained in full, this
21 * software may be distributed under the terms of the GNU General
22 * Public License ("GPL") version 2, in which case the provisions of the
23 * GPL apply INSTEAD OF those given above.
25 * The provided data structures and external interfaces from this code
26 * are not restricted to be used by modules with a GPL compatible license.
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
43 #include <linux/module.h>
44 #include <linux/stddef.h>
45 #include <linux/init.h>
46 #include <linux/kmod.h>
47 #include <linux/slab.h>
48 #include <linux/list.h>
49 #include <linux/spinlock.h>
50 #include <linux/rcupdate.h>
51 #include <linux/uaccess.h>
52 #include <linux/net.h>
53 #include <linux/netdevice.h>
54 #include <linux/socket.h>
55 #include <linux/if_ether.h>
56 #include <linux/if_arp.h>
57 #include <linux/skbuff.h>
58 #include <linux/can.h>
59 #include <linux/can/core.h>
60 #include <linux/can/skb.h>
61 #include <linux/ratelimit.h>
62 #include <net/net_namespace.h>
67 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
68 MODULE_LICENSE("Dual BSD/GPL");
69 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
70 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
72 MODULE_ALIAS_NETPROTO(PF_CAN
);
74 static int stats_timer __read_mostly
= 1;
75 module_param(stats_timer
, int, S_IRUGO
);
76 MODULE_PARM_DESC(stats_timer
, "enable timer for statistics (default:on)");
78 static int can_net_id
;
80 static struct kmem_cache
*rcv_cache __read_mostly
;
82 /* table of registered CAN protocols */
83 static const struct can_proto
*proto_tab
[CAN_NPROTO
] __read_mostly
;
84 static DEFINE_MUTEX(proto_tab_lock
);
86 struct timer_list can_stattimer
; /* timer for statistics update */
87 struct s_stats can_stats
; /* packet statistics */
88 struct s_pstats can_pstats
; /* receive list statistics */
90 static atomic_t skbcounter
= ATOMIC_INIT(0);
93 * af_can socket functions
96 int can_ioctl(struct socket
*sock
, unsigned int cmd
, unsigned long arg
)
98 struct sock
*sk
= sock
->sk
;
103 return sock_get_timestamp(sk
, (struct timeval __user
*)arg
);
109 EXPORT_SYMBOL(can_ioctl
);
111 static void can_sock_destruct(struct sock
*sk
)
113 skb_queue_purge(&sk
->sk_receive_queue
);
116 static const struct can_proto
*can_get_proto(int protocol
)
118 const struct can_proto
*cp
;
121 cp
= rcu_dereference(proto_tab
[protocol
]);
122 if (cp
&& !try_module_get(cp
->prot
->owner
))
129 static inline void can_put_proto(const struct can_proto
*cp
)
131 module_put(cp
->prot
->owner
);
134 static int can_create(struct net
*net
, struct socket
*sock
, int protocol
,
138 const struct can_proto
*cp
;
141 sock
->state
= SS_UNCONNECTED
;
143 if (protocol
< 0 || protocol
>= CAN_NPROTO
)
146 cp
= can_get_proto(protocol
);
148 #ifdef CONFIG_MODULES
150 /* try to load protocol module if kernel is modular */
152 err
= request_module("can-proto-%d", protocol
);
155 * In case of error we only print a message but don't
156 * return the error code immediately. Below we will
157 * return -EPROTONOSUPPORT
160 printk_ratelimited(KERN_ERR
"can: request_module "
161 "(can-proto-%d) failed.\n", protocol
);
163 cp
= can_get_proto(protocol
);
167 /* check for available protocol and correct usage */
170 return -EPROTONOSUPPORT
;
172 if (cp
->type
!= sock
->type
) {
179 sk
= sk_alloc(net
, PF_CAN
, GFP_KERNEL
, cp
->prot
, kern
);
185 sock_init_data(sock
, sk
);
186 sk
->sk_destruct
= can_sock_destruct
;
188 if (sk
->sk_prot
->init
)
189 err
= sk
->sk_prot
->init(sk
);
192 /* release sk on errors */
207 * can_send - transmit a CAN frame (optional with local loopback)
208 * @skb: pointer to socket buffer with CAN frame in data section
209 * @loop: loopback for listeners on local CAN sockets (recommended default!)
211 * Due to the loopback this routine must not be called from hardirq context.
215 * -ENETDOWN when the selected interface is down
216 * -ENOBUFS on full driver queue (see net_xmit_errno())
217 * -ENOMEM when local loopback failed at calling skb_clone()
218 * -EPERM when trying to send on a non-CAN interface
219 * -EMSGSIZE CAN frame size is bigger than CAN interface MTU
220 * -EINVAL when the skb->data does not contain a valid CAN frame
222 int can_send(struct sk_buff
*skb
, int loop
)
224 struct sk_buff
*newskb
= NULL
;
225 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
228 if (skb
->len
== CAN_MTU
) {
229 skb
->protocol
= htons(ETH_P_CAN
);
230 if (unlikely(cfd
->len
> CAN_MAX_DLEN
))
232 } else if (skb
->len
== CANFD_MTU
) {
233 skb
->protocol
= htons(ETH_P_CANFD
);
234 if (unlikely(cfd
->len
> CANFD_MAX_DLEN
))
240 * Make sure the CAN frame can pass the selected CAN netdevice.
241 * As structs can_frame and canfd_frame are similar, we can provide
242 * CAN FD frames to legacy CAN drivers as long as the length is <= 8
244 if (unlikely(skb
->len
> skb
->dev
->mtu
&& cfd
->len
> CAN_MAX_DLEN
)) {
249 if (unlikely(skb
->dev
->type
!= ARPHRD_CAN
)) {
254 if (unlikely(!(skb
->dev
->flags
& IFF_UP
))) {
259 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
261 skb_reset_mac_header(skb
);
262 skb_reset_network_header(skb
);
263 skb_reset_transport_header(skb
);
266 /* local loopback of sent CAN frames */
268 /* indication for the CAN driver: do loopback */
269 skb
->pkt_type
= PACKET_LOOPBACK
;
272 * The reference to the originating sock may be required
273 * by the receiving socket to check whether the frame is
274 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
275 * Therefore we have to ensure that skb->sk remains the
276 * reference to the originating sock by restoring skb->sk
277 * after each skb_clone() or skb_orphan() usage.
280 if (!(skb
->dev
->flags
& IFF_ECHO
)) {
282 * If the interface is not capable to do loopback
283 * itself, we do it here.
285 newskb
= skb_clone(skb
, GFP_ATOMIC
);
291 can_skb_set_owner(newskb
, skb
->sk
);
292 newskb
->ip_summed
= CHECKSUM_UNNECESSARY
;
293 newskb
->pkt_type
= PACKET_BROADCAST
;
296 /* indication for the CAN driver: no loopback required */
297 skb
->pkt_type
= PACKET_HOST
;
300 /* send to netdevice */
301 err
= dev_queue_xmit(skb
);
303 err
= net_xmit_errno(err
);
313 /* update statistics */
314 can_stats
.tx_frames
++;
315 can_stats
.tx_frames_delta
++;
323 EXPORT_SYMBOL(can_send
);
329 static struct dev_rcv_lists
*find_dev_rcv_lists(struct net
*net
,
330 struct net_device
*dev
)
333 return net
->can
.can_rx_alldev_list
;
335 return (struct dev_rcv_lists
*)dev
->ml_priv
;
339 * effhash - hash function for 29 bit CAN identifier reduction
340 * @can_id: 29 bit CAN identifier
343 * To reduce the linear traversal in one linked list of _single_ EFF CAN
344 * frame subscriptions the 29 bit identifier is mapped to 10 bits.
345 * (see CAN_EFF_RCV_HASH_BITS definition)
348 * Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask )
350 static unsigned int effhash(canid_t can_id
)
355 hash
^= can_id
>> CAN_EFF_RCV_HASH_BITS
;
356 hash
^= can_id
>> (2 * CAN_EFF_RCV_HASH_BITS
);
358 return hash
& ((1 << CAN_EFF_RCV_HASH_BITS
) - 1);
362 * find_rcv_list - determine optimal filterlist inside device filter struct
363 * @can_id: pointer to CAN identifier of a given can_filter
364 * @mask: pointer to CAN mask of a given can_filter
365 * @d: pointer to the device filter struct
368 * Returns the optimal filterlist to reduce the filter handling in the
369 * receive path. This function is called by service functions that need
370 * to register or unregister a can_filter in the filter lists.
372 * A filter matches in general, when
374 * <received_can_id> & mask == can_id & mask
376 * so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe
377 * relevant bits for the filter.
379 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
380 * filter for error messages (CAN_ERR_FLAG bit set in mask). For error msg
381 * frames there is a special filterlist and a special rx path filter handling.
384 * Pointer to optimal filterlist for the given can_id/mask pair.
385 * Constistency checked mask.
386 * Reduced can_id to have a preprocessed filter compare value.
388 static struct hlist_head
*find_rcv_list(canid_t
*can_id
, canid_t
*mask
,
389 struct dev_rcv_lists
*d
)
391 canid_t inv
= *can_id
& CAN_INV_FILTER
; /* save flag before masking */
393 /* filter for error message frames in extra filterlist */
394 if (*mask
& CAN_ERR_FLAG
) {
395 /* clear CAN_ERR_FLAG in filter entry */
396 *mask
&= CAN_ERR_MASK
;
397 return &d
->rx
[RX_ERR
];
400 /* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */
402 #define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG)
404 /* ensure valid values in can_mask for 'SFF only' frame filtering */
405 if ((*mask
& CAN_EFF_FLAG
) && !(*can_id
& CAN_EFF_FLAG
))
406 *mask
&= (CAN_SFF_MASK
| CAN_EFF_RTR_FLAGS
);
408 /* reduce condition testing at receive time */
411 /* inverse can_id/can_mask filter */
413 return &d
->rx
[RX_INV
];
415 /* mask == 0 => no condition testing at receive time */
417 return &d
->rx
[RX_ALL
];
419 /* extra filterlists for the subscription of a single non-RTR can_id */
420 if (((*mask
& CAN_EFF_RTR_FLAGS
) == CAN_EFF_RTR_FLAGS
) &&
421 !(*can_id
& CAN_RTR_FLAG
)) {
423 if (*can_id
& CAN_EFF_FLAG
) {
424 if (*mask
== (CAN_EFF_MASK
| CAN_EFF_RTR_FLAGS
))
425 return &d
->rx_eff
[effhash(*can_id
)];
427 if (*mask
== (CAN_SFF_MASK
| CAN_EFF_RTR_FLAGS
))
428 return &d
->rx_sff
[*can_id
];
432 /* default: filter via can_id/can_mask */
433 return &d
->rx
[RX_FIL
];
437 * can_rx_register - subscribe CAN frames from a specific interface
438 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
439 * @can_id: CAN identifier (see description)
440 * @mask: CAN mask (see description)
441 * @func: callback function on filter match
442 * @data: returned parameter for callback function
443 * @ident: string for calling module identification
444 * @sk: socket pointer (might be NULL)
447 * Invokes the callback function with the received sk_buff and the given
448 * parameter 'data' on a matching receive filter. A filter matches, when
450 * <received_can_id> & mask == can_id & mask
452 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
453 * filter for error message frames (CAN_ERR_FLAG bit set in mask).
455 * The provided pointer to the sk_buff is guaranteed to be valid as long as
456 * the callback function is running. The callback function must *not* free
457 * the given sk_buff while processing it's task. When the given sk_buff is
458 * needed after the end of the callback function it must be cloned inside
459 * the callback function with skb_clone().
463 * -ENOMEM on missing cache mem to create subscription entry
464 * -ENODEV unknown device
466 int can_rx_register(struct net
*net
, struct net_device
*dev
, canid_t can_id
,
467 canid_t mask
, void (*func
)(struct sk_buff
*, void *),
468 void *data
, char *ident
, struct sock
*sk
)
471 struct hlist_head
*rl
;
472 struct dev_rcv_lists
*d
;
475 /* insert new receiver (dev,canid,mask) -> (func,data) */
477 if (dev
&& dev
->type
!= ARPHRD_CAN
)
480 if (dev
&& !net_eq(net
, dev_net(dev
)))
483 r
= kmem_cache_alloc(rcv_cache
, GFP_KERNEL
);
487 spin_lock(&net
->can
.can_rcvlists_lock
);
489 d
= find_dev_rcv_lists(net
, dev
);
491 rl
= find_rcv_list(&can_id
, &mask
, d
);
501 hlist_add_head_rcu(&r
->list
, rl
);
504 can_pstats
.rcv_entries
++;
505 if (can_pstats
.rcv_entries_max
< can_pstats
.rcv_entries
)
506 can_pstats
.rcv_entries_max
= can_pstats
.rcv_entries
;
508 kmem_cache_free(rcv_cache
, r
);
512 spin_unlock(&net
->can
.can_rcvlists_lock
);
516 EXPORT_SYMBOL(can_rx_register
);
519 * can_rx_delete_receiver - rcu callback for single receiver entry removal
521 static void can_rx_delete_receiver(struct rcu_head
*rp
)
523 struct receiver
*r
= container_of(rp
, struct receiver
, rcu
);
524 struct sock
*sk
= r
->sk
;
526 kmem_cache_free(rcv_cache
, r
);
532 * can_rx_unregister - unsubscribe CAN frames from a specific interface
533 * @dev: pointer to netdevice (NULL => unsubscribe from 'all' CAN devices list)
534 * @can_id: CAN identifier
536 * @func: callback function on filter match
537 * @data: returned parameter for callback function
540 * Removes subscription entry depending on given (subscription) values.
542 void can_rx_unregister(struct net
*net
, struct net_device
*dev
, canid_t can_id
,
543 canid_t mask
, void (*func
)(struct sk_buff
*, void *),
546 struct receiver
*r
= NULL
;
547 struct hlist_head
*rl
;
548 struct dev_rcv_lists
*d
;
550 if (dev
&& dev
->type
!= ARPHRD_CAN
)
553 if (dev
&& !net_eq(net
, dev_net(dev
)))
556 spin_lock(&net
->can
.can_rcvlists_lock
);
558 d
= find_dev_rcv_lists(net
, dev
);
560 pr_err("BUG: receive list not found for "
561 "dev %s, id %03X, mask %03X\n",
562 DNAME(dev
), can_id
, mask
);
566 rl
= find_rcv_list(&can_id
, &mask
, d
);
569 * Search the receiver list for the item to delete. This should
570 * exist, since no receiver may be unregistered that hasn't
571 * been registered before.
574 hlist_for_each_entry_rcu(r
, rl
, list
) {
575 if (r
->can_id
== can_id
&& r
->mask
== mask
&&
576 r
->func
== func
&& r
->data
== data
)
581 * Check for bugs in CAN protocol implementations using af_can.c:
582 * 'r' will be NULL if no matching list item was found for removal.
586 WARN(1, "BUG: receive list entry not found for dev %s, "
587 "id %03X, mask %03X\n", DNAME(dev
), can_id
, mask
);
591 hlist_del_rcu(&r
->list
);
594 if (can_pstats
.rcv_entries
> 0)
595 can_pstats
.rcv_entries
--;
597 /* remove device structure requested by NETDEV_UNREGISTER */
598 if (d
->remove_on_zero_entries
&& !d
->entries
) {
604 spin_unlock(&net
->can
.can_rcvlists_lock
);
606 /* schedule the receiver item for deletion */
610 call_rcu(&r
->rcu
, can_rx_delete_receiver
);
613 EXPORT_SYMBOL(can_rx_unregister
);
615 static inline void deliver(struct sk_buff
*skb
, struct receiver
*r
)
617 r
->func(skb
, r
->data
);
621 static int can_rcv_filter(struct dev_rcv_lists
*d
, struct sk_buff
*skb
)
625 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
626 canid_t can_id
= cf
->can_id
;
631 if (can_id
& CAN_ERR_FLAG
) {
632 /* check for error message frame entries only */
633 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_ERR
], list
) {
634 if (can_id
& r
->mask
) {
642 /* check for unfiltered entries */
643 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_ALL
], list
) {
648 /* check for can_id/mask entries */
649 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_FIL
], list
) {
650 if ((can_id
& r
->mask
) == r
->can_id
) {
656 /* check for inverted can_id/mask entries */
657 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_INV
], list
) {
658 if ((can_id
& r
->mask
) != r
->can_id
) {
664 /* check filterlists for single non-RTR can_ids */
665 if (can_id
& CAN_RTR_FLAG
)
668 if (can_id
& CAN_EFF_FLAG
) {
669 hlist_for_each_entry_rcu(r
, &d
->rx_eff
[effhash(can_id
)], list
) {
670 if (r
->can_id
== can_id
) {
676 can_id
&= CAN_SFF_MASK
;
677 hlist_for_each_entry_rcu(r
, &d
->rx_sff
[can_id
], list
) {
686 static void can_receive(struct sk_buff
*skb
, struct net_device
*dev
)
688 struct dev_rcv_lists
*d
;
691 /* update statistics */
692 can_stats
.rx_frames
++;
693 can_stats
.rx_frames_delta
++;
695 /* create non-zero unique skb identifier together with *skb */
696 while (!(can_skb_prv(skb
)->skbcnt
))
697 can_skb_prv(skb
)->skbcnt
= atomic_inc_return(&skbcounter
);
701 /* deliver the packet to sockets listening on all devices */
702 matches
= can_rcv_filter(dev_net(dev
)->can
.can_rx_alldev_list
, skb
);
704 /* find receive list for this device */
705 d
= find_dev_rcv_lists(dev_net(dev
), dev
);
707 matches
+= can_rcv_filter(d
, skb
);
711 /* consume the skbuff allocated by the netdevice driver */
716 can_stats
.matches_delta
++;
720 static int can_rcv(struct sk_buff
*skb
, struct net_device
*dev
,
721 struct packet_type
*pt
, struct net_device
*orig_dev
)
723 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
725 if (WARN_ONCE(dev
->type
!= ARPHRD_CAN
||
726 skb
->len
!= CAN_MTU
||
727 cfd
->len
> CAN_MAX_DLEN
,
728 "PF_CAN: dropped non conform CAN skbuf: "
729 "dev type %d, len %d, datalen %d\n",
730 dev
->type
, skb
->len
, cfd
->len
))
733 can_receive(skb
, dev
);
734 return NET_RX_SUCCESS
;
741 static int canfd_rcv(struct sk_buff
*skb
, struct net_device
*dev
,
742 struct packet_type
*pt
, struct net_device
*orig_dev
)
744 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
746 if (WARN_ONCE(dev
->type
!= ARPHRD_CAN
||
747 skb
->len
!= CANFD_MTU
||
748 cfd
->len
> CANFD_MAX_DLEN
,
749 "PF_CAN: dropped non conform CAN FD skbuf: "
750 "dev type %d, len %d, datalen %d\n",
751 dev
->type
, skb
->len
, cfd
->len
))
754 can_receive(skb
, dev
);
755 return NET_RX_SUCCESS
;
763 * af_can protocol functions
767 * can_proto_register - register CAN transport protocol
768 * @cp: pointer to CAN protocol structure
772 * -EINVAL invalid (out of range) protocol number
773 * -EBUSY protocol already in use
774 * -ENOBUF if proto_register() fails
776 int can_proto_register(const struct can_proto
*cp
)
778 int proto
= cp
->protocol
;
781 if (proto
< 0 || proto
>= CAN_NPROTO
) {
782 pr_err("can: protocol number %d out of range\n", proto
);
786 err
= proto_register(cp
->prot
, 0);
790 mutex_lock(&proto_tab_lock
);
792 if (proto_tab
[proto
]) {
793 pr_err("can: protocol %d already registered\n", proto
);
796 RCU_INIT_POINTER(proto_tab
[proto
], cp
);
798 mutex_unlock(&proto_tab_lock
);
801 proto_unregister(cp
->prot
);
805 EXPORT_SYMBOL(can_proto_register
);
808 * can_proto_unregister - unregister CAN transport protocol
809 * @cp: pointer to CAN protocol structure
811 void can_proto_unregister(const struct can_proto
*cp
)
813 int proto
= cp
->protocol
;
815 mutex_lock(&proto_tab_lock
);
816 BUG_ON(proto_tab
[proto
] != cp
);
817 RCU_INIT_POINTER(proto_tab
[proto
], NULL
);
818 mutex_unlock(&proto_tab_lock
);
822 proto_unregister(cp
->prot
);
824 EXPORT_SYMBOL(can_proto_unregister
);
827 * af_can notifier to create/remove CAN netdevice specific structs
829 static int can_notifier(struct notifier_block
*nb
, unsigned long msg
,
832 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
833 struct dev_rcv_lists
*d
;
835 if (dev
->type
!= ARPHRD_CAN
)
840 case NETDEV_REGISTER
:
842 /* create new dev_rcv_lists for this device */
843 d
= kzalloc(sizeof(*d
), GFP_KERNEL
);
846 BUG_ON(dev
->ml_priv
);
851 case NETDEV_UNREGISTER
:
852 spin_lock(&dev_net(dev
)->can
.can_rcvlists_lock
);
857 d
->remove_on_zero_entries
= 1;
863 pr_err("can: notifier: receive list not found for dev "
866 spin_unlock(&dev_net(dev
)->can
.can_rcvlists_lock
);
874 static int can_pernet_init(struct net
*net
)
876 net
->can
.can_rcvlists_lock
=
877 __SPIN_LOCK_UNLOCKED(net
->can
.can_rcvlists_lock
);
878 net
->can
.can_rx_alldev_list
=
879 kzalloc(sizeof(struct dev_rcv_lists
), GFP_KERNEL
);
881 if (IS_ENABLED(CONFIG_PROC_FS
))
887 static void can_pernet_exit(struct net
*net
)
889 struct net_device
*dev
;
891 if (IS_ENABLED(CONFIG_PROC_FS
))
892 can_remove_proc(net
);
894 /* remove created dev_rcv_lists from still registered CAN devices */
896 for_each_netdev_rcu(net
, dev
) {
897 if (dev
->type
== ARPHRD_CAN
&& dev
->ml_priv
) {
898 struct dev_rcv_lists
*d
= dev
->ml_priv
;
907 kfree(net
->can
.can_rx_alldev_list
);
911 * af_can module init/exit functions
914 static struct packet_type can_packet __read_mostly
= {
915 .type
= cpu_to_be16(ETH_P_CAN
),
919 static struct packet_type canfd_packet __read_mostly
= {
920 .type
= cpu_to_be16(ETH_P_CANFD
),
924 static const struct net_proto_family can_family_ops
= {
926 .create
= can_create
,
927 .owner
= THIS_MODULE
,
930 /* notifier block for netdevice event */
931 static struct notifier_block can_netdev_notifier __read_mostly
= {
932 .notifier_call
= can_notifier
,
935 static struct pernet_operations can_pernet_ops __read_mostly
= {
936 .init
= can_pernet_init
,
937 .exit
= can_pernet_exit
,
942 static __init
int can_init(void)
944 /* check for correct padding to be able to use the structs similarly */
945 BUILD_BUG_ON(offsetof(struct can_frame
, can_dlc
) !=
946 offsetof(struct canfd_frame
, len
) ||
947 offsetof(struct can_frame
, data
) !=
948 offsetof(struct canfd_frame
, data
));
950 pr_info("can: controller area network core (" CAN_VERSION_STRING
")\n");
952 rcv_cache
= kmem_cache_create("can_receiver", sizeof(struct receiver
),
957 if (IS_ENABLED(CONFIG_PROC_FS
)) {
959 /* the statistics are updated every second (timer triggered) */
960 setup_timer(&can_stattimer
, can_stat_update
, 0);
961 mod_timer(&can_stattimer
, round_jiffies(jiffies
+ HZ
));
965 register_pernet_subsys(&can_pernet_ops
);
967 /* protocol register */
968 sock_register(&can_family_ops
);
969 register_netdevice_notifier(&can_netdev_notifier
);
970 dev_add_pack(&can_packet
);
971 dev_add_pack(&canfd_packet
);
976 static __exit
void can_exit(void)
978 if (IS_ENABLED(CONFIG_PROC_FS
)) {
980 del_timer_sync(&can_stattimer
);
983 /* protocol unregister */
984 dev_remove_pack(&canfd_packet
);
985 dev_remove_pack(&can_packet
);
986 unregister_netdevice_notifier(&can_netdev_notifier
);
987 sock_unregister(PF_CAN
);
989 unregister_pernet_subsys(&can_pernet_ops
);
991 rcu_barrier(); /* Wait for completion of call_rcu()'s */
993 kmem_cache_destroy(rcv_cache
);
996 module_init(can_init
);
997 module_exit(can_exit
);