From 8b01939f358d680cea971151375268cfdb6b9635 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:33:02 +0200 Subject: 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: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- net/can/af_can.c | 109 +++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 82 insertions(+), 27 deletions(-) (limited to 'net/can') diff --git a/net/can/af_can.c b/net/can/af_can.c index c96140a1458e..821022a7214f 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -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 == 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; - if (skb->len != sizeof(struct can_frame) || cf->can_dlc > 8) { - kfree_skb(skb); - return -EINVAL; + /* + * 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); -- cgit v1.2.1