Re: [PATCH RFC] ext3 data=guarded v5

[Theodore Tso <tytso@mit.edu>]

On Wed, Apr 29, 2009 at 03:41:29PM -0400, Chris Mason wrote:
> 
> I think my latest patch has this nailed down without the mutex.
> Basically it checks i_nlink with super lock held and then calls
> ext3_orphan_del.  If we race with unlink, we'll either find the new
> nlink count and skip the orphan del or unlink will come in after us and
> add the orphan back.

Can you make sure you mark any lock_super()'s with a comment saying
what it's protecting?  Eventually I suspect we'll want to forward port
this to ext4, and I have a patch in the ext4 patch queue that I mean
to backport to ext3 which introduces an explicit i_orphan_lock mutex
and eliminates most of the calls to lock/unlock_super() in support of
a cleanup which Christoph is planning.  So it'll make life easier if
you annotate any use of lock_super(), since it's going to be going
away in both ext3 and ext4 in the near future.

Thanks!!

							- Ted