From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-fsdevel-owner@vger.kernel.org>
Received: from bombadil.infradead.org ([198.137.202.133]:39576 "EHLO
        bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1726819AbeIMVVH (ORCPT
        <rfc822;linux-fsdevel@vger.kernel.org>);
        Thu, 13 Sep 2018 17:21:07 -0400
Date: Thu, 13 Sep 2018 09:10:54 -0700
From: Matthew Wilcox <willy@infradead.org>
To: David Howells <dhowells@redhat.com>
Cc: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org,
        linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 00/10] iov_iter: Add new iters and use with AFS
Message-ID: <20180913161054.GB11574@bombadil.infradead.org>
References: <153685389564.14766.11306559824641824935.stgit@warthog.procyon.org.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <153685389564.14766.11306559824641824935.stgit@warthog.procyon.org.uk>
Sender: linux-fsdevel-owner@vger.kernel.org
List-ID: <linux-fsdevel.vger.kernel.org>

On Thu, Sep 13, 2018 at 04:51:35PM +0100, David Howells wrote:
>  (5) Add an ITER_DISCARD iterator type.  This provides an iterator that
>      simply discards anything written to it.  It cannot be used as a data
>      source.

May I suggest an ITER_ZERO iterator type instead?  It acts like /dev/zero;
writes are discarded (as you have here) and reads return zeroes.
I've wanted such a thing in the past, but got distracted away from
that project.