From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:47493)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1axtlw-0007HE-Ac
	for qemu-devel@nongnu.org; Wed, 04 May 2016 06:11:18 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1axtlk-00065i-FU
	for qemu-devel@nongnu.org; Wed, 04 May 2016 06:11:06 -0400
Date: Wed, 4 May 2016 12:10:23 +0200
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20160504101023.GB14972@noname.str.redhat.com>
References: <1461030177-29144-1-git-send-email-famz@redhat.com>
	<1461030177-29144-2-git-send-email-famz@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1461030177-29144-2-git-send-email-famz@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 1/2] block: Invalidate all children
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel/>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Fam Zheng <famz@redhat.com>
Cc: qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>, qemu-block@nongnu.org

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