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

[Laurent Vivier]

Le vendredi 07 novembre 2008 à 09:54 +0100, Kevin Wolf a écrit :
> Laurent Vivier schrieb:
> > 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 <address@hidden>
> >>> ---
> >>>  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.
> 
> No, it's a move which drops a comment and it shouldn't do that. ;-)
> 
> > -        /* better than nothing: return allocated if read error */

Oops...

Laurent
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