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Date: Wed, 14 Aug 2024 05:43:25 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Zorro Lang <zlang@kernel.org>,
	fstests@vger.kernel.org, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 2/5] add a new min_dio_alignment helper
Message-ID: <20240814034325.GA29861@lst.de>
References: <20240813073527.81072-1-hch@lst.de> <20240813073527.81072-3-hch@lst.de> <20240813144004.GD6047@frogsfrogsfrogs>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Tue, Aug 13, 2024 at 07:40:04AM -0700, Darrick J. Wong wrote:
> > +	/*
> > +	 * No support for STATX_DIOALIGN and not a block device:
> > +	 * default to PAGE_SIZE.
> 
> Should we try DIOINFO here as a second to last gasp?

I implemented this last night, but have second thoughts now:

DIOINFO is only implemented for XFS, which both implemented
STATX_DIOALIGN from the start, and where the block size hack works
and is equivalent to the DIOINFO output.  So I don't think this
buys us anything but costs an extra syscall per invocation.

So I plan to drop this again before submission.