Re: [Qemu-devel] [PATCH 1/2] block: Invalidate all children

[Kevin Wolf <kwolf@redhat.com>]

Am 19.04.2016 um 03:42 hat Fam Zheng geschrieben:
> Currently we only recurse to bs->file, which will miss the children in quorum
> and VMDK.
> 
> Recurse into the whole subtree to avoid that.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>  block.c | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/block.c b/block.c
> index d4939b4..fa8b38f 100644
> --- a/block.c
> +++ b/block.c
> @@ -3201,6 +3201,7 @@ void bdrv_init_with_whitelist(void)
>  
>  void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
>  {
> +    BdrvChild *child;
>      Error *local_err = NULL;
>      int ret;
>  
> @@ -3215,13 +3216,20 @@ void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
>  
>      if (bs->drv->bdrv_invalidate_cache) {
>          bs->drv->bdrv_invalidate_cache(bs, &local_err);
> -    } else if (bs->file) {
> -        bdrv_invalidate_cache(bs->file->bs, &local_err);

The old behaviour was that we only recurse for bs->file if the block
driver doesn't have its own implementation.

This means that in qcow2, for example, we call bdrv_invalidate_cache()
explicitly for bs->file. If we can already invalidate it here, the call
inside qcow2 and probably other drivers could go away.

Kevin