Re: [PATCH 1/6] ext4: Update inode i_size after the preallocation

[Theodore Ts'o <tytso@xxxxxxx>]

On Mon, Feb 17, 2014 at 04:12:14PM -0700, Andreas Dilger wrote:
> 
> I don't necessarily agree about this.  Calling fallocate() will not
> change the user-visible data at all, so there is no reason to e.g.
> do a new backup of the file or reprocess the contents, or any other
> reason that an application cares about a changed mtime.

Well, if i_size has changed, then the visible results of reading from
the file will change, so in that case I'd argue m_time should change.
If the results of reading file doesn't change then we can keep m_time
unchanged --- but since the inode is changing, c_time *should* always
change any time we've made any changes to the extent tree.

                                     - Ted