tcp: allow zerocopy with fastopen
Accept MSG_ZEROCOPY in all the TCP states that allow sendmsg. Remove the explicit check for ESTABLISHED and CLOSE_WAIT states. This requires correctly handling zerocopy state (uarg, sk_zckey) in all paths reachable from other TCP states. Such as the EPIPE case in sk_stream_wait_connect, which a sendmsg() in incorrect state will now hit. Most paths are already safe. Only extension needed is for TCP Fastopen active open. This can build an skb with data in tcp_send_syn_data. Pass the uarg along with other fastopen state, so that this skb also generates a zerocopy notification on release. Tested with active and passive tcp fastopen packetdrill scripts at https://github.com/wdebruij/packetdrill/commit/1747eef03d25a2404e8132817d0f1244fd6f129d Signed-off-by:Willem de Bruijn <willemb@google.com> Signed-off-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
84239b44
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