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Subject: Re: [PATCH 2/2] ubifs: Allow O_DIRECT
From: Artem Bityutskiy <dedekind1@gmail.com>
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To: Christoph Hellwig <hch@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>, Richard Weinberger
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Date: Mon, 24 Aug 2015 11:02:42 +0300
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On Mon, 2015-08-24 at 00:53 -0700, Christoph Hellwig wrote:
> On Mon, Aug 24, 2015 at 10:13:25AM +0300, Artem Bityutskiy wrote:
> > 1. we are the only FS erroring out on O_DIRECT
> > 2. other file-systems not supporting direct IO just fake it
> 
> There are lots of file systems not supporting O_DIRECT, but ubifs
> might
> be the most common one.  Given that O_DIRECT implementations aren't
> hard, so what's holding back a real implementation?

Back when we were writing UBIFS, we did not need direct IO, so we did
not implement it. But yes, probably someone who cares could just try
implementing this feature.

Artem.