Re: [PATCH 5/5] update i_disksize coherently with block allocation

[Theodore Ts'o <tytso@mit.edu>]

On Fri, Aug 22, 2014 at 03:32:27PM +0400, Dmitry Monakhov wrote:
> Writeback call trace looks like follows:
> ext4_writepages
>  while(nr_pages)
>  ->journal_start
>  ->mpage_map_and_submit_extent -> may alloc some blocks
>    ->mpage_map_one_extent
>  ->journal_stop
> In case of delalloc block i_disksize may be less than i_size. So we have to
> update i_disksize each time we allocated and submitted some blocks beyond
> i_disksize. And we MUST update it in the same transaction, otherwise this
> result in fs-inconsistency in case of upcoming power-failure.
> 
> Another possible way to fix that issue is to insert inode to orhphan list
> on ext4_writepages entrance.
> 
> testcase: xfstest generic/019
> 
> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>

Hi Dmitry, were you seeing generic/019 fail before this patch series?
I've been trying to build a kernel with CONFIG_FAIL_MAKE_REQUEST and I
haven't been able to get generic/019 to fail on me.  Is there
something else we need in order to reliably trigger the test fail?

Thanks,

					- Ted