Re: [dm-devel] [PATCH] fix hard-coded disk header chunk size for persistent snapshot

[Mikulas Patocka <mpatocka redhat com>]

On Wed, 12 May 2010, Alasdair G Kergon wrote:

> On Wed, May 12, 2010 at 10:29:22AM +0900, Tomohiro Kusumi wrote:
> > This patch fixes hard-coded value for the size of a chunk that includes
> > disk header for persistent snapshot. It should be changed to existing
> > macro NUM_SNAPSHOT_HDR_CHUNKS instead of using hard-coded value 1.
>  
> Any more places too?  (E.g. persistent_commit_merge)
> 
> Alasdair

I think the expression in persistent_commit_merge should be changed to:
ps->next_free = area_location(ps, ps->current_area) +
                ps->current_committed + 1;

It is numerically the same, but will avoid trouble if 
NUM_SNAPSHOT_HDR_CHUNKS is increased.

Mikulas