[Ocfs2-devel] lvb length issue [was Re: [ocfs2-tools-devel] question of ocfs2_controld (Jun 27)]

[Joel Becker]

On Thu, Jul 09, 2009 at 01:53:38PM -0500, David Teigland wrote:
> Here's a kernel patch that I've not yet tried.  The code using libdlm will
> need to add the flag 0x00000010 to dlm_new_lockspace().  (Until we've added
> the new LVB64 define to libdlm.h.)
> 
> >From 75e92c78bb0b0002f0253bfe10bef8585a0d52d6 Mon Sep 17 00:00:00 2001
> From: David Teigland <teigland at redhat.com>
> Date: Thu, 9 Jul 2009 13:11:02 -0500
> Subject: [PATCH] dlm: add DLM_LSFL_LVB64 for lockspace creation
> 
> Add a new flag DLM_LSFL_LVB64 to create lockspaces with 64 byte lvbs,
> overriding the lvb length parameter.  It is useful to override the
> fixed 32 byte lvb imposed by the user api when the lockspace is created
> from userspace but used from the kernel.  Locking through the user api
> can still only access 32 byte lvbs.

	Hmm, you're tying a permanent flag to 64bytes, yet userspace
can't get at them?  Seems a bit too ocfs2-tools specific, and yet it
doesn't let ocfs2-tools eventually try to share the lvb.

Joel

-- 

"But all my words come back to me
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Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127