Re: [PATCH 2/2] rpc.nfsd: Allow v4.2 server support with the -V option

["J. Bruce Fields" <bfields@fieldses.org>]

On Tue, Jul 30, 2013 at 04:09:06PM +0000, Myklebust, Trond wrote:
> On Tue, 2013-07-30 at 11:59 -0400, J. Bruce Fields wrote:
> > On Sun, Jul 28, 2013 at 02:36:38PM -0400, Steve Dickson wrote:
> > > Signed-off-by: Steve Dickson <steved@redhat.com>
> > 
> > I agree that we want to be able to turn on 4.2 support with -V, but this
> > does more than that:
> > 
> > > -	if (minorvers41)
> > > -		off += snprintf(ptr+off, sizeof(buf) - off, "%c4.1",
> > > -				minorvers41 > 0 ? '+' : '-');
> > > +	for (n = NFS4_MINMINOR; n <= NFS4_MAXMINOR; n++) {
> > > +		if (NFSCTL_VERISSET(minorvers, n)) 
> > > +			off += snprintf(ptr+off, sizeof(buf) - off, "+4.%d ", n);
> > > +		else			
> > > +			off += snprintf(ptr+off, sizeof(buf) - off, "-4.%d ", n);
> > > +	}
> > >  	for (n = NFSD_MINVERS; n <= NFSD_MAXVERS; n++) {
> > >  		if (NFSCTL_VERISSET(ctlbits, n))
> > >  		    off += snprintf(ptr+off, sizeof(buf) - off, "+%d ", n);
> > 
> > Previously minorvers41 could be set to:
> > 
> > 	 1: turn on 4.1
> > 	-1: turn off 4.1
> > 	 0: keep kernel default (user didn't specify)
> > 
> > This patch removes the "0" case, which I liked.
> 
> Why should NFSv4 minor versions be treated any differently from major
> versions here? We don't have a 'kernel default' for NFSv2 or v3 or v4.0.

I think "run the highest minorversion currently considered sufficiently
mature" is a useful option.

I don't know why that wasn't done for earlier versions.

--b.