Re: extended attributes (need help)

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Mon, Jun 13, 2011 at 09:58:34PM +0200, Emmanuel Dreyfus wrote:
> David Laight <david%l8s.co.uk@localhost> wrote:
> 
> > > Solution is to test for vp->v_vflag & VV_ROOT and unlock the vnode
> > > before calling vn_open or namei, and relocking it afterwards.
> > Is that valid - I assume the root vnode is locked for a reason,
> > you can't just unlock it because a routine you need to call wants
> > to lock it again.
> 
> Here is the code path:
>  
> sys_extattr_set_file
>     extattr_set_vp
>         vn_lock
>         VOP_SETEXTATTR
>             ufs_setextattr
>                 ufs_extattr_set
>                     ufs_extattr_autocreate_attr
>                         *** VOP_UNLOCK added here ***
>                         namei
                          ^^^^^^^ whoah.  Why?

If it's to find the extended-attribute database -- don't do that.
Use a reserved inode like LFS does for the ifile.

Thor