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In-Reply-To: <20210820041158.GA26417@lst.de>
From: Dan Williams <dan.j.williams@intel.com>
Date: Fri, 20 Aug 2021 08:27:14 -0700
Message-ID: <CAPcyv4iQgyPgQhjCwWv9JkA+kx18nRjOucVm+z79uw1zcAbhPg@mail.gmail.com>
Subject: Re: [PATCH 11/30] iomap: add the new iomap_iter model
To: Christoph Hellwig <hch@lst.de>
Cc: "Darrick J. Wong" <djwong@kernel.org>, Matthew Wilcox <willy@infradead.org>, 
	Andreas Gruenbacher <agruenba@redhat.com>, Shiyang Ruan <ruansy.fnst@fujitsu.com>, 
	linux-xfs <linux-xfs@vger.kernel.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>, 
	linux-btrfs <linux-btrfs@vger.kernel.org>, Linux NVDIMM <nvdimm@lists.linux.dev>, 
	cluster-devel@redhat.com
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On Thu, Aug 19, 2021 at 9:12 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Thu, Aug 19, 2021 at 02:25:52PM -0700, Dan Williams wrote:
> > Given most of the iomap_iter users don't care about srcmap, i.e. are
> > not COW cases, they are leaving srcmap zero initialized. Should the
> > IOMAP types be incremented by one so that there is no IOMAP_HOLE
> > confusion? In other words, fold something like this?
>
> A hole really means nothing to read from the source.  The existing code
> also relies on that.

Ok, I've since found iomap_iter_srcmap(). Sorry for the noise.