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Date:   Thu, 20 Oct 2022 12:10:23 +0200
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To:     Pavel Begunkov <asml.silence@gmail.com>,
        io-uring <io-uring@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>
Cc:     Jakub Kicinski <kuba@kernel.org>, netdev <netdev@vger.kernel.org>,
        Dylan Yudaken <dylany@fb.com>
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From:   Stefan Metzmacher <metze@samba.org>
Subject: IORING_SEND_NOTIF_USER_DATA (was Re: IORING_CQE_F_COPIED)
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Hi Pavel,

>> Experimenting with this stuff lets me wish to have a way to
>> have a different 'user_data' field for the notif cqe,
>> maybe based on a IORING_RECVSEND_ flag, it may make my life
>> easier and would avoid some complexity in userspace...
>> As I need to handle retry on short writes even with MSG_WAITALL
>> as EINTR and other errors could cause them.
>>
>> What do you think?

Any comment on this?

IORING_SEND_NOTIF_USER_DATA could let us use
notif->cqe.user_data = sqe->addr3;

metze