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Date:   Mon, 2 Mar 2020 05:31:17 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Christoph Hellwig <hch@infradead.org>,
        Ritesh Harjani <riteshh@linux.ibm.com>,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        darrick.wong@oracle.com
Subject: Re: [PATCH v2] iomap: return partial I/O count on error in
 iomap_dio_bio_actor
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On Fri, Feb 28, 2020 at 02:35:38PM -0600, Goldwyn Rodrigues wrote:
> 
> Ah, okay. Now I understand what Christoph was saying.
> 
> I suppose it is safe to remove iov_iter_reexpand(). I don't see any
> other goto to this label which will have a non-zero copied value.
> And we have already performed the iov_iter_revert().

I don't really understand the iov_iter complexities either, at least
not without spending sifnificant time with the implementation.  But
the important thing is that you document the changes in behavior and
your findings on why you think it is safe.