Re: [PATCH 2/4] design: document realtime groups

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

On Thu, Nov 07, 2024 at 08:33:18AM +0100, Christoph Hellwig wrote:
> > --- a/design/XFS_Filesystem_Structure/allocation_groups.asciidoc
> > +++ b/design/XFS_Filesystem_Structure/allocation_groups.asciidoc
> > @@ -106,6 +106,10 @@ struct xfs_sb
> >  	xfs_lsn_t		sb_lsn;
> >  	uuid_t			sb_meta_uuid;
> >  	xfs_ino_t		sb_metadirino;
> > +	xfs_rgnumber_t		sb_rgcount;
> > +	xfs_rgblock_t		sb_rgextents;
> > +	uint8_t			sb_rgblklog;
> > +	uint8_t			sb_pad[7];
> 
> And following on with my ranting about existing bits theme from the
> previous review:  why are we documenting the in-memory xfs_sb here
> and not the on-disk xfs_dsb?

<nod> will clean that one up too.

> > +| +XFS_SB_FEAT_RO_COMPAT_RTSB+ |
> > +Realtime superblock.  The first rt extent in rt group zero contains a superblock
> > +header that can be used to identify the realtime device.  See the section about
> > +the xref:Realtime_Group_Superblocks[realtime group superblocks] for more
> > +information.
> 
> This is actually gone now.

Oops, will remove that one.

> > +*sb_rgcount*::
> > +Count of realtime groups in the filesystem, if the
> > ++XFS_SB_FEAT_INCOMPAT_RTGROUPS+ feature is enabled.
> 
> ... will be zero if XFS_SB_FEAT_INCOMPAT_RTGROUPS is set, but no
> realtime subvolume exists
> 
> ?

Yeah, that's a good thing to note.  I'll also s/RTGROUPS/METADIR/ since
the rtgroups feature bit is also gone yet I seem to have missed this
one. :(

--D