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Date: Wed, 20 Sep 2017 11:03:43 +0900
Message-ID: <87vakep1mo.wl-satoru.takeuchi@gmail.com>
From: Satoru Takeuchi <satoru.takeuchi@gmail.com>
To: dsterba@suse.cz, Satoru Takeuchi <satoru.takeuchi@gmail.com>,
        Mike Fleetwood <mike.fleetwood@googlemail.com>,
        linux-btrfs <linux-btrfs@vger.kernel.org>
Subject: Re: [PATCH v2] btrfs-progs: allow "none" to disable compression for convenience
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At Tue, 19 Sep 2017 17:14:27 +0200,
David Sterba wrote:
> 
> On Mon, Sep 18, 2017 at 09:41:17AM +0900, Satoru Takeuchi wrote:
> > At Sun, 17 Sep 2017 14:08:40 +0100,
> > Mike Fleetwood wrote:
> > > 
> > > On 17 September 2017 at 01:36, Satoru Takeuchi
> > > <satoru.takeuchi@gmail.com> wrote:
> > > > It's messy to use "" to disable compression. Introduce the new value "no"
> > > > which can also be used for this purpose.
> > > 
> > > From an English language point of view, "none" would be better.  None
> > > says the absence of, where as no is more general negative.
> > 
> > Thank you for your comment. How about is it?
> > 
> > ---
> > It's messy to use "" to disable compression. Introduce the new value "none"
> > which can also be used for this purpose.
> 
> I'd allow both values, 'no' and 'none', similar to the mount options,
> that also accept both (technically, the 'no' + anything is accepted for
> disabling compression).

As a result of reading "man 5 btrfs", now I prefer "no". It's used
to mean disabling compression there. On the other hand, "none" is
not used at all.

>>From man 5 btrfs:
===
...
FILE ATTRIBUTES
...
       compress, compress=type, compress-force, compress-force=type
           (default: off)

           Control BTRFS file data compression. Type may be specified as zlib, lzo or no (for no compression, used for remounting). If no type is specified, zlib is used. If
           compress-force is specified, all files will be compressed, whether or not they compress well.
...
       X
           no compression, permanently turn off compression on the given file, other compression mount options will not affect that
...
===

So David, please apply my v1 patcth if it looks good for you.

Thanks,
Satoru