From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3914C49ED7 for ; Tue, 10 Sep 2019 15:14:37 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CB418206A5 for ; Tue, 10 Sep 2019 15:14:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB418206A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:41266 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7hqm-00049x-Mk for qemu-devel@archiver.kernel.org; Tue, 10 Sep 2019 11:14:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55618) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7hVT-0004sr-OA for qemu-devel@nongnu.org; Tue, 10 Sep 2019 10:52:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i7hVS-0000kY-K9 for qemu-devel@nongnu.org; Tue, 10 Sep 2019 10:52:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53806) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i7hVQ-0000jg-7I; Tue, 10 Sep 2019 10:52:32 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8C4B93082B40; Tue, 10 Sep 2019 14:52:31 +0000 (UTC) Received: from localhost.localdomain (ovpn-116-217.ams2.redhat.com [10.36.116.217]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 822A960BF3; Tue, 10 Sep 2019 14:52:30 +0000 (UTC) Date: Tue, 10 Sep 2019 16:52:29 +0200 From: Kevin Wolf To: Max Reitz Message-ID: <20190910145229.GI4446@localhost.localdomain> References: <20190809161407.11920-1-mreitz@redhat.com> <20190809161407.11920-23-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190809161407.11920-23-mreitz@redhat.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Tue, 10 Sep 2019 14:52:31 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v6 22/42] block: Fix bdrv_get_allocated_file_size's fallback X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 09.08.2019 um 18:13 hat Max Reitz geschrieben: > If the driver does not implement bdrv_get_allocated_file_size(), we > should fall back to cumulating the allocated size of all non-COW > children instead of just bs->file. > > Suggested-by: Vladimir Sementsov-Ogievskiy > Signed-off-by: Max Reitz This smells like an overgeneralisation, but if we want to count all vmdk extents, the qcow2 external data file, etc. it's an improvement anyway. A driver that has a child that should not be counted must just remember to implement the callback. Let me think of an example... How about quorum, for a change? :-) Or the second blkverify child. Or eventually the block job filter nodes. Ehm... Maybe I should just take back what I said first. It almost feels like it would be better if qcow2 and vmdk explicitly used a handler that counts all children (could still be a generic one in block.c) rather than having to remember to disable the functionality everywhere where we don't want to have it. And please adjust the comment for bdrv_get_allocated_file_size(), it only talks about a single file as if trees didn't exist. Actually, it doesn't even seem so easy to define. Maybe primary node + storage nodes? Then vmdk needs to expose its extents as storage nodes (plural!), but in the long run that might be needed anyway. Kevin