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From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
Date:   Fri, 20 May 2022 02:00:07 +0200
Message-ID: <CAHmME9qVQNkx-0J8rq_0ZVaSR+-eEgOUtcZhvq5dAY4-kJxSAA@mail.gmail.com>
Subject: Re: [PATCHSET 0/2] Fix splice from random/urandom
To:     Jens Axboe <axboe@kernel.dk>
Cc:     "Theodore Ts'o" <tytso@mit.edu>, Christoph Hellwig <hch@lst.de>,
        LKML <linux-kernel@vger.kernel.org>
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Hi Jens,

On Fri, May 20, 2022 at 1:57 AM Jens Axboe <axboe@kernel.dk> wrote:
>
> On 5/19/22 5:27 PM, Jason A. Donenfeld wrote:
> > Hi Jens,
> >
> > On Fri, May 20, 2022 at 1:25 AM Jens Axboe <axboe@kernel.dk> wrote:
> >> I'll leave that to you :-)
> >
> > Alright, I'll have a look. Which one do I want here? This series adds
> > splice_read/splice_write. The new thing would be sendpage? Or
> > copy_file_range? Or something else?
>
> For copying kernel memory? It's really the same thing, you just
> initialize the iter as an ITER_KVEC instead. The nice thing about the
> iov_iter iterator that it then hides that for you, call the same copy
> in/out helpers for it.

Err, maybe we're talking about different things? I was thinking about
the plumbing to make splice/sendfile work on non-pipes.

get_random_bytes() itself doesn't need to become iovec'd, as that has
no IO callers.

Jason