From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] add a FMODE flag to make XFS invisible I/O less hacky
Date: Fri, 28 Nov 2008 11:30:52 +0000
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References: <20081128112402.GA32740@lst.de>
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Cc: linux-fsdevel@vger.kernel.org
To: Christoph Hellwig <hch@lst.de>
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On Fri, Nov 28, 2008 at 12:24:02PM +0100, Christoph Hellwig wrote:
> XFS has a mode called invisble I/O that doesn't update any of the
> timestamps.  It's used for HSM-style applications and exposed through
> the nasty open by handle ioctl.
> 
> Instead of doing directly assignment of file operations that set an
> internal flag for it add a new FMODE_INVISIBLE flag that we can check
> in the normal file operations.

Seeing that it's similar to O_NOATIME, why not do it in O_... space?