Re: [Qemu-devel] [PATCH 2/3] vmdk: Make block_status recurse for flat extents

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

25.07.2019 18:55, Max Reitz wrote:
> Fixes: 69f47505ee66afaa513305de0c1895a224e52c45
> Signed-off-by: Max Reitz <mreitz@redhat.com>

Again, don't know vmdk code, but briefly looking at it (and at vmdk spec) I
see that "extents" are files, and flat extent is a raw file without any special
format. And it is allocated by blk_truncate(.. PREALLOC_MODE_OFF ..), so really
looks like metadata preallocation.

And, any way, there should not be real damage, as patch simply brings back old behavior
for one case.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

> ---
>   block/vmdk.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/block/vmdk.c b/block/vmdk.c
> index bd36ece125..fd78fd0ccf 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -1692,6 +1692,9 @@ static int coroutine_fn vmdk_co_block_status(BlockDriverState *bs,
>           if (!extent->compressed) {
>               ret |= BDRV_BLOCK_OFFSET_VALID;
>               *map = cluster_offset + index_in_cluster;
> +            if (extent->flat) {
> +                ret |= BDRV_BLOCK_RECURSE;
> +            }
>           }
>           *file = extent->file->bs;
>           break;
> 


-- 
Best regards,
Vladimir