Re: autoload rpcsec_gss_krb5

From: "J. Bruce Fields" <bfields@fieldses.org>
To: Boaz Harrosh <bharrosh@panasas.com>
Cc: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>,
	linux-nfs@vger.kernel.org, Trond Myklebust <trond@netapp.com>
Subject: Re: autoload rpcsec_gss_krb5
Date: Fri, 24 Jun 2011 10:01:05 -0400	[thread overview]
Message-ID: <20110624140105.GA18829@fieldses.org> (raw)
In-Reply-To: <4E03F4EA.5050206@panasas.com>

On Thu, Jun 23, 2011 at 07:22:34PM -0700, Boaz Harrosh wrote:
> On 06/23/2011 01:30 PM, J. Bruce Fields wrote:
> > On Thu, Jun 23, 2011 at 04:11:17PM -0400, J. Bruce Fields wrote:
> >> On Thu, Jun 23, 2011 at 10:06:14PM +0200, Tigran Mkrtchyan wrote:
> >>> I recall a discussion at connectaton 2010, where Peter Staubach from
> >>> RedHat ( at that time )
> >>> requested a way to disable pNFS without rebuilding the kernel.
> >>>
> >>> Probably that's why autoload is not implemented.
> >>
> >> Well, autoload *is* implemented, you just have to add an alias command
> >> to modprobe.conf before it'll work.
> >>
> >> And if we embed the alias in the module instead, it will still be
> >> possible to disable autloading by adding a "backlist <modulename>" to
> >> modproble.conf.
> >>
> >> So I don't *think* that's the issue, unless I've missed something.
> > 
> > So can we just do this?  (Untested.)
> > 
> > --b.
> > 
> > commit 8b3065071b5469c428d70052c80f1df3cb398da6
> > Author: J. Bruce Fields <bfields@redhat.com>
> > Date:   Thu Jun 23 16:15:39 2011 -0400
> > 
> >     pnfs: simplify pnfs files module autoloading
> >     
> >     Embed the necessary alias into the module rather than waiting for
> >     someone to add it to /etc/modprobe.conf
> >     
> >     Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> > 
> > diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
> > index 4269088..eb65f82 100644
> > --- a/fs/nfs/nfs4filelayout.c
> > +++ b/fs/nfs/nfs4filelayout.c
> > @@ -896,5 +896,7 @@ static void __exit nfs4filelayout_exit(void)
> >  	pnfs_unregister_layoutdriver(&filelayout_type);
> >  }
> >  
> > +MODULE_ALIAS("nfs-layouttype4-1");
> > +
> >  module_init(nfs4filelayout_init);
> >  module_exit(nfs4filelayout_exit);
> diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
> index 70272d5..dd6a453 100644
> --- a/fs/nfs/objlayout/objio_osd.c
> +++ b/fs/nfs/objlayout/objio_osd.c
> @@ -1065,5 +1065,7 @@ objlayout_exit(void)
>  	       __func__);
>  }
>  
> +MODULE_ALIAS("nfs-layouttype4-2");
> +
>  module_init(objlayout_init);
>  module_exit(objlayout_exit);
> ---
> 
> nfs-layouttype4-1
> nfs-layouttype4-2
> ...
> 
> Can we use a name here or it must be the number?

Looks like it needs a number; see the request_module() call in
set_pnfs_layoutdriver:

	request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);

--b.