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Commit 8b01939f authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Marc Kleine-Budde
Browse files

canfd: add support for CAN FD in PF_CAN core 



- handle ETH_P_CAN and ETH_P_CANFD skbuffs
- update sanity checks for CAN and CAN FD
- make sure the CAN frame can pass the selected CAN netdevice on send
- bump core version and abi version to indicate the new CAN FD support

Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 7c941636

include/linux/can/core.h

+2 −2
Original line number Diff line number Diff line
@@ -17,10 +17,10 @@ 
#include <linux/skbuff.h>

#include <linux/netdevice.h>



#define CAN_VERSION "20090105"

#define CAN_VERSION "20120528"



/* increment this number each time you change some user-space interface */

#define CAN_ABI_VERSION "8"

#define CAN_ABI_VERSION "9"



#define CAN_VERSION_STRING "rev " CAN_VERSION " abi " CAN_ABI_VERSION

net/can/af_can.c

+82 −27
Original line number Diff line number Diff line
@@ -221,30 +221,46 @@ static int can_create(struct net *net, struct socket *sock, int protocol, 
 *  -ENOBUFS on full driver queue (see net_xmit_errno())

 *  -ENOMEM when local loopback failed at calling skb_clone()

 *  -EPERM when trying to send on a non-CAN interface

 *  -EMSGSIZE CAN frame size is bigger than CAN interface MTU

 *  -EINVAL when the skb->data does not contain a valid CAN frame

 */

int can_send(struct sk_buff *skb, int loop)

{

	struct sk_buff *newskb = NULL;

	struct can_frame *cf = (struct can_frame *)skb->data;

	int err;

	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;

	int err = -EINVAL;



	if (skb->len != sizeof(struct can_frame) || cf->can_dlc > 8) {

		kfree_skb(skb);

		return -EINVAL;

	if (skb->len == CAN_MTU) {

		skb->protocol = htons(ETH_P_CAN);

		if (unlikely(cfd->len > CAN_MAX_DLEN))

			goto inval_skb;

	} else if (skb->len == CANFD_MTU) {

		skb->protocol = htons(ETH_P_CANFD);

		if (unlikely(cfd->len > CANFD_MAX_DLEN))

			goto inval_skb;

	} else

		goto inval_skb;



	/*

	 * Make sure the CAN frame can pass the selected CAN netdevice.

	 * As structs can_frame and canfd_frame are similar, we can provide

	 * CAN FD frames to legacy CAN drivers as long as the length is <= 8

	 */

	if (unlikely(skb->len > skb->dev->mtu && cfd->len > CAN_MAX_DLEN)) {

		err = -EMSGSIZE;

		goto inval_skb;

	}



	if (skb->dev->type != ARPHRD_CAN) {

		kfree_skb(skb);

		return -EPERM;

	if (unlikely(skb->dev->type != ARPHRD_CAN)) {

		err = -EPERM;

		goto inval_skb;

	}



	if (!(skb->dev->flags & IFF_UP)) {

		kfree_skb(skb);

		return -ENETDOWN;

	if (unlikely(!(skb->dev->flags & IFF_UP))) {

		err = -ENETDOWN;

		goto inval_skb;

	}



	skb->protocol = htons(ETH_P_CAN);

	skb_reset_network_header(skb);

	skb_reset_transport_header(skb);
@@ -301,6 +317,10 @@ int can_send(struct sk_buff *skb, int loop) 
	can_stats.tx_frames_delta++;



	return 0;



inval_skb:

	kfree_skb(skb);

	return err;

}

EXPORT_SYMBOL(can_send);
@@ -633,24 +653,11 @@ static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb) 
	return matches;

}



static int can_rcv(struct sk_buff *skb, struct net_device *dev,

		   struct packet_type *pt, struct net_device *orig_dev)

static void can_receive(struct sk_buff *skb, struct net_device *dev)

{

	struct dev_rcv_lists *d;

	struct can_frame *cf = (struct can_frame *)skb->data;

	int matches;



	if (!net_eq(dev_net(dev), &init_net))

		goto drop;



	if (WARN_ONCE(dev->type != ARPHRD_CAN ||

		      skb->len != sizeof(struct can_frame) ||

		      cf->can_dlc > 8,

		      "PF_CAN: dropped non conform skbuf: "

		      "dev type %d, len %d, can_dlc %d\n",

		      dev->type, skb->len, cf->can_dlc))

		goto drop;



	/* update statistics */

	can_stats.rx_frames++;

	can_stats.rx_frames_delta++;
@@ -674,7 +681,49 @@ static int can_rcv(struct sk_buff *skb, struct net_device *dev, 
		can_stats.matches++;

		can_stats.matches_delta++;

	}

}



static int can_rcv(struct sk_buff *skb, struct net_device *dev,

		   struct packet_type *pt, struct net_device *orig_dev)

{

	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;



	if (unlikely(!net_eq(dev_net(dev), &init_net)))

		goto drop;



	if (WARN_ONCE(dev->type != ARPHRD_CAN ||

		      skb->len != CAN_MTU ||

		      cfd->len > CAN_MAX_DLEN,

		      "PF_CAN: dropped non conform CAN skbuf: "

		      "dev type %d, len %d, datalen %d\n",

		      dev->type, skb->len, cfd->len))

		goto drop;



	can_receive(skb, dev);

	return NET_RX_SUCCESS;



drop:

	kfree_skb(skb);

	return NET_RX_DROP;

}



static int canfd_rcv(struct sk_buff *skb, struct net_device *dev,

		   struct packet_type *pt, struct net_device *orig_dev)

{

	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;



	if (unlikely(!net_eq(dev_net(dev), &init_net)))

		goto drop;



	if (WARN_ONCE(dev->type != ARPHRD_CAN ||

		      skb->len != CANFD_MTU ||

		      cfd->len > CANFD_MAX_DLEN,

		      "PF_CAN: dropped non conform CAN FD skbuf: "

		      "dev type %d, len %d, datalen %d\n",

		      dev->type, skb->len, cfd->len))

		goto drop;



	can_receive(skb, dev);

	return NET_RX_SUCCESS;



drop:
@@ -808,10 +857,14 @@ static int can_notifier(struct notifier_block *nb, unsigned long msg, 


static struct packet_type can_packet __read_mostly = {

	.type = cpu_to_be16(ETH_P_CAN),

	.dev  = NULL,

	.func = can_rcv,

};



static struct packet_type canfd_packet __read_mostly = {

	.type = cpu_to_be16(ETH_P_CANFD),

	.func = canfd_rcv,

};



static const struct net_proto_family can_family_ops = {

	.family = PF_CAN,

	.create = can_create,
@@ -853,6 +906,7 @@ static __init int can_init(void) 
	sock_register(&can_family_ops);

	register_netdevice_notifier(&can_netdev_notifier);

	dev_add_pack(&can_packet);

	dev_add_pack(&canfd_packet);



	return 0;

}
@@ -867,6 +921,7 @@ static __exit void can_exit(void) 
	can_remove_proc();



	/* protocol unregister */

	dev_remove_pack(&canfd_packet);

	dev_remove_pack(&can_packet);

	unregister_netdevice_notifier(&can_netdev_notifier);

	sock_unregister(PF_CAN);