64 	u32 headroom;  in rmnet_vnd_headroom()  local
66 	headroom = sizeof(struct rmnet_map_header);  in rmnet_vnd_headroom()
69 		headroom += sizeof(struct rmnet_map_ul_csum_header);  in rmnet_vnd_headroom()
71 	return headroom;  in rmnet_vnd_headroom()
78 	u32 headroom;  in rmnet_vnd_change_mtu()  local
82 	headroom = rmnet_vnd_headroom(port);  in rmnet_vnd_change_mtu()
85 	    new_mtu > (priv->real_dev->mtu - headroom))  in rmnet_vnd_change_mtu()
220  * flags, ARP type, needed headroom, etc...
256 	u32 headroom;  in rmnet_vnd_newlink()  local
270 	headroom = rmnet_vnd_headroom(port);  in rmnet_vnd_newlink()
272 	if (rmnet_vnd_change_mtu(rmnet_dev, real_dev->mtu - headroom)) {  in rmnet_vnd_newlink()
325 	u32 headroom;  in rmnet_vnd_validate_real_dev_mtu()  local
329 	headroom = rmnet_vnd_headroom(port);  in rmnet_vnd_validate_real_dev_mtu()
332 		if (ep->egress_dev->mtu > (real_dev->mtu - headroom))  in rmnet_vnd_validate_real_dev_mtu()
345 	u32 headroom;  in rmnet_vnd_update_dev_mtu()  local
347 	headroom = rmnet_vnd_headroom(port);  in rmnet_vnd_update_dev_mtu()
350 		if (ep->egress_dev->mtu <= (real_dev->mtu - headroom))  in rmnet_vnd_update_dev_mtu()
354 					 real_dev->mtu - headroom))  in rmnet_vnd_update_dev_mtu()