From mboxrd@z Thu Jan  1 00:00:00 1970
From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Subject: Re: [PATCH v2] fat: editions to support fat_fallocate()
Date: Tue, 23 Oct 2012 16:19:14 +0900
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Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	Ravishankar N <cyberax82@gmail.com>,
	Amit Sahrawat <amit.sahrawat83@gmail.com>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
To: Namjae Jeon <linkinjeon@gmail.com>
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	(Namjae Jeon's message of "Tue, 23 Oct 2012 00:10:03 +0900")
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Namjae Jeon <linkinjeon@gmail.com> writes:

>> Does this break the linux fat driver doesn't know about this
>> fallocate()?  If so, it sounds like to be easy to break existent
>> drivers.
> Yes, it will break linux drivers without fallocate support. When we
> try to write to fallocated file using old drivers, it will cause write
> error and make FS read-only.
> When fallocate was implemented in other filesystem, maybe,, was there
> similar issue and concern  ?

I guess it is not similar. Because other FS can change the spec (e.g. it
can be possible to use feature compat flag for it).
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>