From mboxrd@z Thu Jan  1 00:00:00 1970
From: Theodore Ts'o <tytso@mit.edu>
Subject: Re: Argument type for FS_IOC_GETFLAGS/FS_IOC_SETFLAGS ioctls
Date: Sun, 1 Dec 2013 23:52:32 -0500
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Cc: Andreas Dilger <adilger@dilger.ca>,
	"Darrick J. Wong" <darrick.wong@oracle.com>,
	Aurelien Jarno <aurelien@aurel32.net>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Robert Edmonds <edmonds@debian.org>,
	Rob Browning <rlb@defaultvalue.org>
To: Dave Chinner <david@fromorbit.com>
Return-path: <linux-fsdevel-owner@vger.kernel.org>
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On Mon, Dec 02, 2013 at 09:20:03AM +1100, Dave Chinner wrote:
> Ugh, that'll just screw it up even more. And if we put the ~10 XFS
> flags in there that aren't supported by FS_IOC_GETFLAGS, and all the
> others from other filesystems, we'll be out of space in a couple of
> kernel releases...

What are the definitions XFS flags, and how is XFS currently
setting/getting them, out of curiosity?

> And FWIW, an attribute based approach means you don't need to get
> the flags before setting them to ensure you don't reset flags you
> don't care about, so it's safer from that perspective, too...

Sure, but it will also be more complex, since we'll now have to parse
a whole series of strings and translate them into flags.  ... and then
the m68k and other small device folks will start kvetching about how
the kernel gets bigger with every release, and how their poor
bootlader doesn't support kernels bigger than some arbitrary limit.

> > The options and opportunities for bike shedding are endless.   :-)
> 
> I'm not interested in bike shedding - let's just solve the problem
> once and for all....

I'm curious what the XFS flags are because it's not clear to me
whether the total number of file system attributes that would be
legitimately fs generic are in the dozens, hundreds, or thousands.
There is such a thing as overdesign.

Regards,

						- Ted