Re: [PATCH 8/9] xfs_mdrestore: EXTERNALLOG is a compat value, not incompat

["Darrick J. Wong" <djwong@kernel.org>]

On Wed, Nov 22, 2023 at 10:42:40PM -0800, Christoph Hellwig wrote:
> On Wed, Nov 22, 2023 at 03:07:33PM -0800, Darrick J. Wong wrote:
> > @@ -280,10 +278,8 @@ read_header_v2(
> >  	if (h->v2.xmh_reserved != 0)
> >  		fatal("Metadump header's reserved field has a non-zero value\n");
> >  
> > -	want_external_log = !!(be32_to_cpu(h->v2.xmh_incompat_flags) &
> > -			XFS_MD2_COMPAT_EXTERNALLOG);
> > -
> > -	if (want_external_log && !mdrestore.external_log)
> > +	if ((h->v2.xmh_compat_flags & cpu_to_be32(XFS_MD2_COMPAT_EXTERNALLOG)) &&
> > +	    !mdrestore.external_log)
> 
> Nit: overly long line.  Trivially fixable by just inverting the
> conditions :)

Hmm.  Or I could decode the ondisk field into a stack variable so that
future flags don't have to deal with that:

	compat = be32_to_cpu(h->v2.xmh_compat_flags);

	if (!mdrestore.external_log && (compat & XFS_MD2_COMPAT_EXTERNALLOG))
		fatal("External Log device is required\n");


--D

> 
> Otherwise looks good:
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
>