BUF_HEADROOM       64 net/tipc/msg.c 	unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
BUF_HEADROOM       68 net/tipc/msg.c 		skb_reserve(skb, BUF_HEADROOM);
BUF_HEADROOM      212 net/tipc/msg.c 		skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC);