• Oliver Hartkopp's avatar
    can: add private data space for CAN sk_buffs · 156c2bb9
    Oliver Hartkopp authored
    The struct can_skb_priv is used to transport additional information along
    with the stored struct can(fd)_frame that can not be contained in existing
    struct sk_buff elements.
    
    can_skb_priv is located in the skb headroom, which does not touch the existing
    CAN sk_buff usage with skb->data and skb->len, so that even out-of-tree
    CAN drivers can be used without changes.
    
    Btw. out-of-tree CAN drivers without can_skb_priv in the sk_buff headroom
    would not support features based on can_skb_priv.
    
    The can_skb_priv->ifindex contains the first interface where the CAN frame
    appeared on the local host. Unfortunately skb->skb_iif can not be used as this
    value is overwritten in every netif_receive_skb() call.
    Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
    Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
    156c2bb9
slcan.c 18.3 KB