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

[Changlong Xie <xiecl.fnst@cn.fujitsu.com>]

On 04/19/2016 09:42 AM, Fam Zheng wrote:
> 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);

Kevin's commit 3456a8d1 introduced unexpected two spaces in this 
function, would you like remove it?

-    if (bs->drv && bs->drv->bdrv_invalidate_cache) {
+    if (!bs->drv)  {
+        return;
+    }

> -    } else if (bs->file) {
> -        bdrv_invalidate_cache(bs->file->bs, &local_err);
> +        if (local_err) {
> +            bs->open_flags |= BDRV_O_INACTIVE;
> +            error_propagate(errp, local_err);
> +            return;
> +        }
>       }
> -    if (local_err) {
> -        bs->open_flags |= BDRV_O_INACTIVE;
> -        error_propagate(errp, local_err);
> -        return;
> +
> +    QLIST_FOREACH(child, &bs->children, next) {
> +        bdrv_invalidate_cache(child->bs, &local_err);
> +        if (local_err) {
> +            bs->open_flags |= BDRV_O_INACTIVE;
> +            error_propagate(errp, local_err);
> +            return;

If we really need return here? I just mean for example, Quorum A has 3 
children(children.0, children.1, children.2), if we invalidate 
children.1 failed, then we are not going to invalidate children.2

> +        }
>       }
>
>       ret = refresh_total_sectors(bs, bs->total_sectors);
>