Re: [Qemu-devel] [PATCH 1/4] qcow2: Clean-up update_cluster_refcount().

[Laurent Vivier <Laurent.Vivier@bull.net>]

Le jeudi 06 novembre 2008 à 18:32 +0100, Kevin Wolf a écrit :
> Laurent Vivier schrieb:
> > pièce jointe document texte brut
> > (0001-Clean-up-update_cluster_refcount.patch)
> > Move some parts to alloc_refcount_block() and block cache
> >  checking to load_refcount_block().
> > 
> > Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
> > ---
> >  block-qcow2.c |   71 +++++++++++++++++++++++++++++++++++-----------------------
> >  1 file changed, 43 insertions(+), 28 deletions(-)
> > 
> > Index: qemu/block-qcow2.c
> > ===================================================================
> > --- qemu.orig/block-qcow2.c	2008-11-06 16:34:46.000000000 +0100
> > +++ qemu/block-qcow2.c	2008-11-06 16:40:27.000000000 +0100
> > @@ -2169,6 +2169,10 @@ static int load_refcount_block(BlockDriv
> >  {
> >      BDRVQcowState *s = bs->opaque;
> >      int ret;
> > +
> > +    if (refcount_block_offset == s->refcount_block_cache_offset)
> > +        return 0;
> > +
> >      ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache,
> >                       s->cluster_size);
> >      if (ret != s->cluster_size)
> > @@ -2189,11 +2193,8 @@ static int get_refcount(BlockDriverState
> >      refcount_block_offset = s->refcount_table[refcount_table_index];
> >      if (!refcount_block_offset)
> >          return 0;
> > -    if (refcount_block_offset != s->refcount_block_cache_offset) {
> > -        /* better than nothing: return allocated if read error */
> > -        if (load_refcount_block(bs, refcount_block_offset) < 0)
> > -            return 1;
> > -    }
> > +    if (load_refcount_block(bs, refcount_block_offset) < 0)
> > +        return 1;
> 
> Please retain the comment saying that 1 is not the correct value but we
> default to allocated for safety if the block could not be read. I don't
> think this is obvious.

I totally agree with you, but it's just a code move, I don't want to
change anything except the line numbers.

I think this kind of change must have its own patch.

Regards,
Laurent
-- 
------------------ Laurent.Vivier@bull.net  ------------------
"Tout ce qui est impossible reste à accomplir"    Jules Verne
"Things are only impossible until they're not" Jean-Luc Picard