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Date:   Mon, 4 Jul 2022 05:37:10 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Filipe Manana <fdmanana@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 2/3] btrfs: don't fallback to buffered IO for NOWAIT
 direct IO writes
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On Mon, Jul 04, 2022 at 01:19:36PM +0100, Filipe Manana wrote:
> First time I'm hearing it, and never had complaints before.

Take a look at Documentation/process/coding-style.rst.

> Why is it wrong? The purpose it to never fallback directly to buffered IO if
> it's a NOWAIT write. Moving the check to above the label, would make the
> non-aligned case fallback directly to buffered IO under NOWAIT.

Oh, indeed. I keep forgetting that btrfs is unusual in that it does not
fail unaligned direct I/O like all other file systems but just falls
back to buffered I/O instead.