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>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 5c95018..a6e0355 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1608,6 +1608,7 @@ struct tcp_fastopen_request {
struct msghdr *data; /* data in MSG_FASTOPEN */
size_t size;
int copied; /* queued in tcp_connect() */
+ struct ubuf_info *uarg;
};
void tcp_free_fastopen_req(struct tcp_sock *tp);
void tcp_fastopen_destroy_cipher(struct sock *sk);