[Ocfs2-tools-devel] [PATCH 17/20] fsck.ocfs2: Make pass0 aware of discontig block group.

[Joel Becker]

On Sat, Jul 17, 2010 at 04:22:59PM +0800, Tao Ma wrote:
> On 07/17/2010 08:06 AM, Joel Becker wrote:
> >	I didn't see a patch in this series where repair_group_desc()
> >checks the extent list in the discontig descriptor.  Did I miss that?
> You are right. I don't implement it.
> The reason is that we now never check allocations for any block
> group. And also in case we find duplicate clusters for chain
> allocator, we skip it and do nothing.

	Hmm?  We certainly do our best to sanity check the gd fields.
You are right that duplicate clusters are handled separately.  But what
about an l_next_free_rec that is too large?  What about a discontig bg
whose extents don't add up to cl_cpg?
	Right now, if we find a bad magic or bad generation, we'll just
drop it.  Why not do the same for a really screwed up extent list.  I'm
not asking to walk the extent list to see if the global bitmap has the
bits or something.

> So do you think we should break this by adding extent list check for
> the discontiguous block group?
> If that is the truth, I think we may also need to check other block
> group as well. And that would be a new task for ocfs2-tools.

	Btw, we do check the allocation of chains.  Their clusters are
added to the bitmaps, and if they are overlapping other things, we copy
out those other things in pass1d.  But that's not what I'm talking about
here.

Joel

-- 

"Only a life lived for others is a life worth while."
							-Albert Einstein  

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