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Message-ID: <d289ab2c-dd5a-fd35-2a2a-7ccdfb947873@kernel.org>
Date:   Mon, 19 Jun 2023 19:09:27 -0700
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Subject: Re: [RFC PATCH v2 1/4] net: wire up support for
 file_operations->uring_cmd()
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To:     Pavel Begunkov <asml.silence@gmail.com>,
        Breno Leitao <leitao@debian.org>, io-uring@vger.kernel.org,
        axboe@kernel.dk, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com,
        Matthieu Baerts <matthieu.baerts@tessares.net>,
        Mat Martineau <martineau@kernel.org>,
        Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
        Xin Long <lucien.xin@gmail.com>
Cc:     leit@fb.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        dccp@vger.kernel.org, mptcp@lists.linux.dev,
        linux-sctp@vger.kernel.org, ast@kernel.org, kuniyu@amazon.com,
        martin.lau@kernel.org, Jason Xing <kernelxing@tencent.com>,
        Joanne Koong <joannelkoong@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Willem de Bruijn <willemb@google.com>,
        Guillaume Nault <gnault@redhat.com>,
        Andrea Righi <andrea.righi@canonical.com>
References: <20230614110757.3689731-1-leitao@debian.org>
 <20230614110757.3689731-2-leitao@debian.org>
 <6b5e5988-3dc7-f5d6-e447-397696c0d533@kernel.org>
 <d9c9bd5f-b17e-fbd8-5646-4f51b927cc6b@gmail.com>
From:   David Ahern <dsahern@kernel.org>
In-Reply-To: <d9c9bd5f-b17e-fbd8-5646-4f51b927cc6b@gmail.com>
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On 6/19/23 2:28 AM, Pavel Begunkov wrote:
> That callback is all about file dependent operations, just like ioctl.
> And as the patch in question is doing socket specific stuff, I think
> architecturally it fits well. I also believe Breno wants to extend it
> later to support more operations.
> 
> Sockets are a large chunk of use cases, it can be implemented as a
> separate io_uring request type if nothing else works, but in general
> that might not be as scalable.

The io_uring commands are wrappers to existing networking APIs - doing
via io_uring what userspace apps can do via system calls. As such, the
translations should be done in io_uring code and then invoking in-kernel
APIs.

Same comment applies to sockopts when those come around and any other
future extensions.