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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 19 Jan 2021 09:25:20 -0800
Message-ID: <CAHk-=wi_CDqKUZ50QkEhKrAwuEm=qLs=rEFf8e2uUWEqL13oGw@mail.gmail.com>
Subject: Re: Splicing to/from a tty
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Christoph Hellwig <hch@lst.de>, Oliver Giles <ohw.giles@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Jiri Slaby <jirislaby@kernel.org>
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On Tue, Jan 19, 2021 at 3:54 AM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> This looks sane, but I'm still missing what the goal of this is here.
> It's nice from a "don't make the ldisc do the userspace copy", point of
> view, but what is the next step in order to tie that into splice?

I'll cook something up. With this, it should be fairly easy to add
both the splice and iov_iter versions, because now it only needs the
wrappers in tty_io.c, not for each line discipline.

I hope. Let's see..

           Linus