Re: [PATCH 3/3] Add the code for adding the mountee to the merged filesystems

[olafBuddenhagen]

Hi,

On Fri, Jul 10, 2009 at 08:22:51PM +0300, Sergiu Ivanov wrote:
> On Fri, Jul 10, 2009 at 04:20:35AM +0200, olafBuddenhagen@gmx.net
> wrote:
> > On Sun, Jul 05, 2009 at 06:53:50PM +0300, Sergiu Ivanov wrote:

> > > ulfs_check is used to update the list of ports to the underlying
> > > filesystems maintained by unionfs, while node_init_root is used to
> > > store a (similar) list of ports in the root node.
> > > 
> > > unionfs invokes both of these functions only in
> > > _root_update_thread and does this with the point of doing a global
> > > synchronization, i.e. making sure the merged directories still
> > > exist and dropping dead items.
> > > 
> > > I call these functions explicitly because I want to force the
> > > update of the list of filesystems and the root node.
> > 
> > Why?
> 
> Ah, sure, I forgot to tell the most important bit :-( The greater part
> of what these updating routines do is making sure that the list of
> filesystems is consistent, updating the corresponding list in the root
> node, and opening the ports to the roots of these filesystems.  If I
> don't do the update, the mountee will not be included in the list of
> merged filesystems and the user will not see the mountee's filesystem
> at all.

I still don't understand why this needs to be done differently with
unionmount than without mounting. I either case, the list of filesystems
needs do be kept consistent in the very same way I would think?...

My guess would be that obtaining the root nodes at this place might be a
good way to force the mountee startup at a defined place -- but
according to your explanation this in not the purpose, so I really don't
get it.

-antrik-