From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH v8 1/4] fat: add fat_fallocate operation
Date: Wed, 10 Dec 2014 02:45:24 -0800
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Cc: 'Luk?? Czerner' <lczerner@redhat.com>,
	'OGAWA Hirofumi' <hirofumi@mail.parknet.co.jp>,
	'Andrew Morton' <akpm@linux-foundation.org>,
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To: Namjae Jeon <namjae.jeon@samsung.com>
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On Wed, Dec 10, 2014 at 07:42:16PM +0900, Namjae Jeon wrote:
> User have to call fallocate again if opening file after close().
> And fallocate() will skip allocation if fallocated blocks is avaiable.
> Instead, It gurrantee to be available fallocated blocks between open
> and close(). And I updated such limitation of fat fallocate in
> Documentation.

Documentation doesn't help, this breaks application exposed semantics.

If you think there is a use case for non-persistant preallocations
please propose a new fallocate flag for it, or given the lack of use
case probably just add a fat specific ioctl instead.