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Date:   Tue, 16 Mar 2021 08:43:16 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     "Darrick J. Wong" <djwong@kernel.org>
Cc:     Brian Foster <bfoster@redhat.com>,
        Chandan Babu R <chandanrlinux@gmail.com>,
        Dave Chinner <david@fromorbit.com>, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 05/45] xfs: async blkdev cache flush
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On Mon, Mar 15, 2021 at 09:32:22AM -0700, Darrick J. Wong wrote:
> Yes, I agree with that principle.  However, the use case for !done isn't
> clear ot me -- what is the point of issuing a flush and not waiting for
> the results?

There is none.  This check should go away.

> 
> Can PREFLUSHes generate IO errors?  And if they do, why don't we return
> the error to the caller?

The caller owns the bio and can look at bi_status itself.