Re: [PATCH v4 15/16] block: sed-opal: don't repeat opal_discovery0 in each steps array

[David Kozub]

On Fri, 8 Feb 2019, Derrick, Jonathan wrote:

> On Mon, 2019-02-04 at 23:44 +0100, David Kozub wrote:
> > On Mon, 4 Feb 2019, Christoph Hellwig wrote:
> >
> > > > +	/* first do a discovery0 */
> > > > +	error = opal_discovery0_step(dev);
> > > >
> > > > +	for (state = 0; !error && state < n_steps; state++)
> > > > +		error = execute_step(dev, &steps[state], state);
> > > > +
> > > > +	/*
> > > > +	 * For each OPAL command the first step in steps starts some sort of
> > > > +	 * session. If an error occurred in the initial discovery0 or if an
> > > > +	 * error occurred in the first step (and thus stopping the loop with
> > > > +	 * state == 1) then there was an error before or during the attempt to
> > > > +	 * start a session. Therefore we shouldn't attempt to terminate a
> > > > +	 * session, as one has not yet been created.
> > > > +	 */
> > > > +	if (error && state > 1)
> > > > +		end_opal_session_error(dev);
> > > >
> > > >  	return error;
> > >
> > > The flow here is a little too condensed for my taste.  Why not the
> > > plain obvoious, if a little longer:
> > >
> > > 	error = error = opal_discovery0_step(dev);
> > > 	if (error)
> > > 		return error;
> > >
> > > 	for (state = 0; state < n_steps; state++) {
> > > 		error = execute_step(dev, &steps[state], state);
> > > 		if (error)
> > > 			goto out_error;
> > > 	}
> > >
> > > 	return 0;
> > >
> > > out_error:
> > > 	if (state > 1)
> > > 		end_opal_session_error(dev);
> > > 	return error;
> >
> > No problem, I can use this version. But I think there is a minor issue -
> > the same one I hit in my original change, just from the other direction:
> >
> > If the loop succeds for the 0-th element of steps, and then fails for the
> > 1st element, then state equals 1 yet the session has been started, so we
> > should close it.
> >
> > I think the condition in out_error should be if (state > 0).
> >
> > Best regards,
> > David
> Looks good with Christoph's suggestion (for 14/16) and your state check fix
>
>
> Reviewed-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>

Hi Jon,

What suggestion by Christoph you have in mind? I don't see any for 14/16. 
Currently, in my git repo, for this patch, I applied Christoph suggestion 
for this (15/16) patch + the "state > 0" fix. Is this what you mean?

Best regards,
David