reserved_tailroom 856 include/linux/skbuff.h __u32 reserved_tailroom; reserved_tailroom 2329 include/linux/skbuff.h return skb->end - skb->tail - skb->reserved_tailroom; reserved_tailroom 2364 include/linux/skbuff.h skb->reserved_tailroom = skb_tailroom(skb) - mtu; reserved_tailroom 2367 include/linux/skbuff.h skb->reserved_tailroom = needed_tailroom; reserved_tailroom 901 net/ipv4/tcp.c skb->reserved_tailroom = skb->end - skb->tail - size;