mbuf: add a way to mark flowid as calculated from the internal headers

[kib]

Summary

In some settings offload might calculate hash from decapsulated packet. Reserve a bit in packet header rsstype to indicate that.

Add m_adj_decap() that acts similarly to m_adj, but also either clear flowid if it is not marked as inner, or transfer it to the decapsulated header, clearing inner indicator. It depends on the internals of m_adj() that reuses the argument packet header for the result.

Use m_adj_decap() for decapsulating vxlan(4) and gif(4) input packets.

Sponsored by: Nvidia Networking / Mellanox Technologies

[• hselasky]

sys/sys/mbuf.h

561

M_HASHTYPE_GET(m) -> (m)->m_pkthdr.rsstype

Then you save an AND operation.

[kib]

sys/sys/mbuf.h

561

I am sure that compiler does not generate to ands there, but ok.

[kib]

Hans suggestion, unwind one level of macro.

[ae]

sys/kern/uipc_mbuf.c

866

s/In/If/

[• hselasky]

Looks good.