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From: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
To: "'Joel Becker'" <jlbec@evilplan.org>,
        "'Sebastian Andrzej Siewior'" <bigeasy@linutronix.de>
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Subject: RE: [RFC 0/2] USB gadget - configfs
Date: Wed, 29 Aug 2012 15:17:53 +0200
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Hello Joel,

On Monday, August 20, 2012 8:00 AM Joel Becker wrote:

<snip>

> 	I think what you want here is a symlink.  Create a directory high in
> the tree called 'ready' or 'available', and when you want to lock the
> device in place, symlink it into that directory.  This will pin the item.
> You can also make use of the ->allow_link() and ->drop_link() callbacks to
> prevent symlinking an item until it is fully configured, and prevent
> unlinking an item that is in use.
> 

I have a question to you. In fs/configfs/dir.c, in a comment before
configfs_depend_item and configfs_depend_prep you say that "configfs uses
VFS to handle all locking". I am trying to understand how this
works. Could you please elaborate a bit about it? Which locks from VFS
handle "all locking"? When does locking happen?

Thanks,

Andrzej