[Ocfs2-devel] [PATCH] ocfs2: Implement llseek()

[Sunil Mushran]

On 05/19/2011 04:05 AM, Christoph Hellwig wrote:
> On Wed, May 18, 2011 at 07:44:44PM -0700, Sunil Mushran wrote:
>> Unwritten (preallocated) extents are considered holes because the file system
>> treats reads to such regions in the same way as it does to holes.
> How does this work for the case of an unwrittent extent that has been
> written to in the pagecache but not converted yet?  Y'know the big data
> corruption and flamewar that started all this?

We don't delay splitting the extent. It is split in ->write_begin(). Delaying
it will be a challenge as we have to provide cache coherency across the
cluster.