Re: [PATCH v6 05/15] ubifs: Rename whiteout atomically

[Richard Weinberger]

----- Ursprüngliche Mail -----
>> The whiteout inode is clean after creation from create_whiteout(), and
>> it can't be marked dirty until ubifs_jnl_rename() finished. So, I think
>> there is no chance for whiteout being written on disk. Then,
>> 'ubifs_assert(c, !whiteout_ui->dirty)' never fails in ubifs_jnl_rename()
>> during my local stress tests. You may add some delay executions after
>> whiteout creation to make sure that whiteout won't be written back
>> before ubifs_jnl_rename().
> 
> From UBIFS point of view I fully agree with you. I'm just a little puzzled why
> other filesystems use the tmpfile approach. My fear is that VFS can do things
> to the inode we don't have in mind right now.

After digging a bit into XFS I'm sure your approach is okay.
So, UBIFS can do a whiteout without help of tmpfiles. :-)

Thanks,
//richard