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Date: Wed, 23 Nov 2011 23:11:26 +0200
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Subject: Re: [V3 PATCH 1/2] tmpfs: add fallocate support
From: Pekka Enberg <penberg@kernel.org>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Cong Wang <amwang@redhat.com>, linux-kernel@vger.kernel.org,
        akpm@linux-foundation.org, Christoph Hellwig <hch@lst.de>,
        Hugh Dickins <hughd@google.com>, Dave Hansen <dave@linux.vnet.ibm.com>,
        Lennart Poettering <lennart@poettering.net>,
        Kay Sievers <kay.sievers@vrfy.org>, linux-mm@kvack.org
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On Wed, Nov 23, 2011 at 9:59 PM, KOSAKI Motohiro
<kosaki.motohiro@jp.fujitsu.com> wrote:
>> +
>> +       goto unlock;
>> +
>> +undo:
>> +       while (index > start) {
>> +               shmem_truncate_page(inode, index);
>> +               index--;
>
> Hmmm...
> seems too aggressive truncate if the file has pages before starting fallocate.
> but I have no idea to make better undo. ;)

Why do we need to undo anyway?

                                Pekka