From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v2 net-next 1/2] tcp: add TCP_ZEROCOPY_RECEIVE support for
 zerocopy receive
Date: Thu, 26 Apr 2018 06:47:54 -0700
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Cc: netdev <netdev@vger.kernel.org>, Andy Lutomirski <luto@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        Soheil Hassas Yeganeh <soheil@google.com>
To: Ka-Cheong Poon <ka-cheong.poon@oracle.com>,
        Eric Dumazet <edumazet@google.com>,
        "David S . Miller" <davem@davemloft.net>
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On 04/26/2018 06:40 AM, Ka-Cheong Poon wrote:

> A quick question.  Is it a normal practice to return a result
> in setsockopt() given that the optval parameter is supposed to
> be a const void *?

Very good question.

Andy suggested an ioctl() or setsockopt(), and I chose setsockopt() but it looks
like a better choice would have been getsockopt() indeed.

This might even allow future changes in "struct tcp_zerocopy_receive"

Willem suggested to add code in tcp_recvmsg() but I prefer to not bloat this already too complex function.

I will send a v3 using getsockopt() then, thanks !