Add support for RX checksum offload of encapsulated packets. This essentially just means paying attention to the inner checksum flags in the RX event, and if *either* checksum flag indicates a fail then don't tell the kernel that checksum offload was successful. Also, count these checksum errors and export the counts to ethtool -S. Test the most common "good" case of RX events with a single bitmask instead of a series of ifs. Move the more specific error checking in to a separate function for clarity, and don't use unlikely() there since we know at least one of the bits is bad. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>