1 /* 2 * linux/can/skb.h 3 * 4 * Definitions for the CAN network socket buffer 5 * 6 * Copyright (C) 2012 Oliver Hartkopp <[email protected]> 7 * 8 */ 9 10 #ifndef CAN_SKB_H 11 #define CAN_SKB_H 12 13 #include <linux/types.h> 14 #include <linux/can.h> 15 16 /* 17 * The struct can_skb_priv is used to transport additional information along 18 * with the stored struct can(fd)_frame that can not be contained in existing 19 * struct sk_buff elements. 20 * N.B. that this information must not be modified in cloned CAN sk_buffs. 21 * To modify the CAN frame content or the struct can_skb_priv content 22 * skb_copy() needs to be used instead of skb_clone(). 23 */ 24 25 /** 26 * struct can_skb_priv - private additional data inside CAN sk_buffs 27 * @ifindex: ifindex of the first interface the CAN frame appeared on 28 * @cf: align to the following CAN frame at skb->data 29 */ 30 struct can_skb_priv { 31 int ifindex; 32 struct can_frame cf[0]; 33 }; 34 35 static inline struct can_skb_priv *can_skb_prv(struct sk_buff *skb) 36 { 37 return (struct can_skb_priv *)(skb->head); 38 } 39 40 static inline void can_skb_reserve(struct sk_buff *skb) 41 { 42 skb_reserve(skb, sizeof(struct can_skb_priv)); 43 } 44 45 #endif /* CAN_SKB_H */ 46