Re: [PATCH v7 13/20] nfs: implement client support for NFS_LOCALIO_PROGRAM

[Mike Snitzer <snitzer@kernel.org>]

On Wed, Jun 26, 2024 at 09:21:00AM +1000, NeilBrown wrote:
> On Tue, 25 Jun 2024, Mike Snitzer wrote:
> > LOCALIOPROC_GETUUID allows a client to discover the server's uuid.
> > 
> > nfs_local_probe() will retrieve server's uuid via LOCALIO protocol and
> > verify the server with that uuid it is known to be local. This ensures
> > client and server 1: support localio 2: are local to each other.
> > 
> > All the knowledge of the LOCALIO RPC protocol is in fs/nfs/localio.c
> > which implements just a single version (1) that is used independently
> > of what NFS version is used.
> > 
> > Get nfsd_open_local_fh and store it in rpc_client during client
> > creation, put the symbol during nfs_local_disable -- which is also
> > called during client destruction.
> > 
> > Signed-off-by: Mike Snitzer <snitzer@kernel.org>
> > [neilb: factored out and simplified single localio protocol]
> > Co-developed-by: NeilBrown <neilb@suse.de>
> > Signed-off-by: NeilBrown <neilb@suse.de>
> > ---
> >  fs/nfs/client.c     |   6 +-
> >  fs/nfs/localio.c    | 159 +++++++++++++++++++++++++++++++++++++++++---
> >  include/linux/nfs.h |   7 ++
> >  3 files changed, 161 insertions(+), 11 deletions(-)
> > 
> > diff --git a/fs/nfs/client.c b/fs/nfs/client.c
> > index 1300c388f971..6faa9fdc444d 100644
> > --- a/fs/nfs/client.c
> > +++ b/fs/nfs/client.c
> > @@ -434,8 +434,10 @@ struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
> >  			list_add_tail(&new->cl_share_link,
> >  					&nn->nfs_client_list);
> >  			spin_unlock(&nn->nfs_client_lock);
> > -			nfs_local_probe(new);
> > -			return rpc_ops->init_client(new, cl_init);
> > +			new = rpc_ops->init_client(new, cl_init);
> > +			if (!IS_ERR(new))
> > +				 nfs_local_probe(new);
> > +			return new;
> 
> I would fold this back into the earlier patch that introduced
> nfs_local_probe().  It makes this patch ugly.
> But I won't insist.

I cleaned it up a bit so that this patch is cleaner, but I'd prefer to
leave it split out.

Thanks.
Mike