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To:     Damien Le Moal <Damien.LeMoal@wdc.com>,
        Dave Chinner <david@fromorbit.com>,
        linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Hannes Reinecke <hare@suse.de>,
        Johannes Thumshirn <jth@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Naohiro Aota <Naohiro.Aota@wdc.com>
Subject: Re: [v12 1/2] fs: New zonefs file system
From:   Markus Elfring <Markus.Elfring@web.de>
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Date:   Fri, 7 Feb 2020 08:18:09 +0100
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> > Hmmm. I'm wondering if it would be better to return -EOPNOTSUPP here
> > so that the application knows it can't do non-blocking write AIO to
> > this file.
>
> I wondered the same too. In the end, I decided to go with silently ignor=
ing
> the flag (for now) since raw block device accesses do the same (the NOWA=
IT
> support is not complete and IOs may wait on free tags). I have an idea f=
or
> fixing simply the out-of-order issuing that may result from using nowait=
.

I find this aspect interesting for further clarification.


> I will send a patch for that later and can then remove this.

Should another software improvement be integrated into the initial proposa=
l?

Regards,
Markus