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Date:   Sun, 5 Jul 2020 04:27:32 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Jan Ziak <0xe2.0x9a.0x9b@gmail.com>
Cc:     gregkh@linuxfoundation.org, linux-api@vger.kernel.org,
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        linux-kselftest@vger.kernel.org, linux-man@vger.kernel.org,
        mtk.manpages@gmail.com, shuah@kernel.org, viro@zeniv.linux.org.uk
Subject: Re: [PATCH 0/3] readfile(2): a new syscall to make open/read/close
 faster
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On Sun, Jul 05, 2020 at 05:18:58AM +0200, Jan Ziak wrote:
> On Sun, Jul 5, 2020 at 5:12 AM Matthew Wilcox <willy@infradead.org> wrote:
> >
> > You should probably take a look at io_uring.  That has the level of
> > complexity of this proposal and supports open/read/close along with many
> > other opcodes.
> 
> Then glibc can implement readfile using io_uring and there is no need
> for a new single-file readfile syscall.

It could, sure.  But there's also a value in having a simple interface
to accomplish a simple task.  Your proposed API added a very complex
interface to satisfy needs that clearly aren't part of the problem space
that Greg is looking to address.