net/usbnet: reserve headroom on rx skbs
net/usbnet: reserve headroom on rx skbs

network drivers should reserve some headroom on incoming skbs so that we
dont need expensive reallocations, eg forwarding packets in tunnels.

This NET_SKB_PAD padding is done in various helpers, like
__netdev_alloc_skb_ip_align() in this patch, combining NET_SKB_PAD and
NET_IP_ALIGN magic.

Signed-off-by: Eric Dumazet <a0baddf32b28d2f9429941ed4af2fe636e210591@gmail.com>
Cc: Oliver Neukum <bfee72d94d376f4e00f72b756466867d7f9eb24e@suse.de>
Cc: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>
Acked-by: Oliver Neukum <bfee72d94d376f4e00f72b756466867d7f9eb24e@suse.de>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas