From nobody Sun Oct 5 21:15:27 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 154224789234955.63101244214636; Wed, 14 Nov 2018 18:11:32 -0800 (PST) Received: from localhost ([::1]:35645 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gN77z-00080D-0r for importer@patchew.org; Wed, 14 Nov 2018 21:11:31 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53760) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gN70u-0002QA-Ni for qemu-devel@nongnu.org; Wed, 14 Nov 2018 21:04:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gN70r-0005kj-HL for qemu-devel@nongnu.org; Wed, 14 Nov 2018 21:04:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60456) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gN70m-0005gT-1p; Wed, 14 Nov 2018 21:04:04 -0500 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 888E213A5C; Thu, 15 Nov 2018 02:04:02 +0000 (UTC) Received: from red.redhat.com (ovpn-123-32.rdu2.redhat.com [10.10.123.32]) by smtp.corp.redhat.com (Postfix) with ESMTP id BB18E60BF6; Thu, 15 Nov 2018 02:04:01 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Wed, 14 Nov 2018 20:03:32 -0600 Message-Id: <20181115020334.1189829-12-eblake@redhat.com> In-Reply-To: <20181115020334.1189829-1-eblake@redhat.com> References: <20181115020334.1189829-1-eblake@redhat.com> 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 [10.5.110.29]); Thu, 15 Nov 2018 02:04:02 +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: [Qemu-devel] [PATCH v2 11/13] qcow2: Audit for read/write 64-bit cleanness X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The qcow2 read/write functions do their own fragmentation (because of cluster remapping); while we could advertise s->cluster_size and let the block layer do fragmentation for us, that would NOT solve the issue of the block layer handing us a length less than a cluster but at an offset which overlaps a cluster boundary. Thus, we still have to fragment ourselves, at which point it is easiest to just document that this driver is 64-bit clean. Signed-off-by: Eric Blake --- block/qcow2.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/qcow2.c b/block/qcow2.c index 0b5ad130060..1dd3491f77f 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1687,6 +1687,7 @@ static void qcow2_refresh_limits(BlockDriverState *bs= , Error **errp) } bs->bl.pwrite_zeroes_alignment =3D s->cluster_size; bs->bl.pdiscard_alignment =3D s->cluster_size; + bs->bl.max_transfer =3D INT64_MAX; } static int qcow2_reopen_prepare(BDRVReopenState *state, --=20 2.17.2