[Ocfs2-tools-devel] [PATCH 06/22] libocfs2: Make ocfs2_init_group_desc aware of discontig group.

[Joel Becker]

On Thu, Apr 01, 2010 at 04:54:07PM -0700, Mark Fasheh wrote:
> On Thu, Apr 01, 2010 at 03:21:04AM -0700, Joel Becker wrote:
> > 	It's better if we have a way to know the group descriptor is
> > discontiguous without knowing the inode and superblock.  Then the
> > feature tests are mere sanity.
> > 	We can add bg_flags as you describe above.  Another option is to
> > see that bg_bitmap + bg_size == offsetof(bg_list).  Both work.  The
> > former is more descriptive, the latter is less invasive.  Which works
> > for you?  Mark?
> 
> I think doing it this way (bg_size + bg_bitmap) is fine - bg_size is
> identical on all ocfs2 volumes at their given clustersize / block size, so
> the test you describe above would always work. And we'd get to save on some
> already-small fields in our allocation groups.

	Works for me.  Now we can key on ocfs2_gd_is_discontig() instead
of !ocfs2_is_cluster_alloc() && ocfs2_supports_discontig_bg() &&
bg_list.l_next_free_rec.

Joel

-- 

"I have never let my schooling interfere with my education."
        - Mark Twain

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127