Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley
        Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United
        Kingdom.
        Registered in England and Wales under Company Registration No. 3798903
From:   David Howells <dhowells@redhat.com>
In-Reply-To: <YwWgdekd+f3MqVmu@infradead.org>
References: <YwWgdekd+f3MqVmu@infradead.org> <166126392703.708021.14465850073772688008.stgit@warthog.procyon.org.uk> <166126393409.708021.16165278011941496946.stgit@warthog.procyon.org.uk>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     dhowells@redhat.com, Steve French <smfrench@gmail.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Shyam Prasad N <nspmangalore@gmail.com>,
        Rohith Surabattula <rohiths.msft@gmail.com>,
        Jeff Layton <jlayton@kernel.org>, linux-cifs@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/7] iov_iter: Add a function to extract an iter's buffers to a bvec iter
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <1584070.1665756368.1@warthog.procyon.org.uk>
Content-Transfer-Encoding: quoted-printable
Date:   Fri, 14 Oct 2022 15:06:08 +0100
Message-ID: <1584071.1665756368@warthog.procyon.org.uk>
Precedence: bulk

Christoph Hellwig <hch@infradead.org> wrote:

> On Tue, Aug 23, 2022 at 03:12:14PM +0100, David Howells wrote:
> > Copy cifs's setup_aio_ctx_iter() and to lib/iov_iter.c and generalise =
it as
> > extract_iter_to_iter().  This allocates and sets up an array of bio_ve=
cs
> > for all the page fragments in an I/O iterator and sets a second suppli=
ed
> > iterator to bvec-type pointing to the array.
> =

> Did you read my NACK and comments from last time?

No, because they ended up in a different mailbox from everything else for =
some
reason.

> I really do not like this as a general purpose helper.  This is an odd
> quirk that we really generally should not needed unless you have very
> convoluted locking.  So please keep it inside of cifs.

I'm using it in under-development netfslib code also.

Let me ask the question more generally in a separate email.

David