From nobody Thu Nov 6 16:02:45 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.zoho.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; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1489441607397126.39392787050167; Mon, 13 Mar 2017 14:46:47 -0700 (PDT) Received: from localhost ([::1]:54562 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnXni-0003On-0D for importer@patchew.org; Mon, 13 Mar 2017 17:46:46 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43826) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnXiF-0007cK-CL for qemu-devel@nongnu.org; Mon, 13 Mar 2017 17:41:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cnXiE-0001wr-J7 for qemu-devel@nongnu.org; Mon, 13 Mar 2017 17:41:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40210) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cnXiC-0001vQ-7w; Mon, 13 Mar 2017 17:41:04 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 62E133B720; Mon, 13 Mar 2017 21:41:04 +0000 (UTC) Received: from localhost (ovpn-204-63.brq.redhat.com [10.40.204.63]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v2DLf2lB015201 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 13 Mar 2017 17:41:03 -0400 From: Max Reitz To: qemu-block@nongnu.org Date: Mon, 13 Mar 2017 22:40:38 +0100 Message-Id: <20170313214045.26857-7-mreitz@redhat.com> In-Reply-To: <20170313214001.26339-1-mreitz@redhat.com> References: <20170313214001.26339-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Mon, 13 Mar 2017 21:41:04 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH for-2.10 09/16] block/qcow2: Generalize preallocate() 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: Kevin Wolf , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This patch adds two new parameters to the preallocate() function so we will be able to use it not just for preallocating a new image but also for preallocated image growth. The offset parameter allows the caller to specify a virtual offset from which to start preallocating. For newly created images this is always 0, but for preallocating growth this will be the old image length. The new_length parameter specifies the supposed new length of the image (basically the "end offset" for preallocation). During image truncation, bdrv_getlength() will return the old image length so we cannot rely on its return value then. Signed-off-by: Max Reitz --- block/qcow2.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 210646b60f..9abdf9e0fb 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2034,17 +2034,16 @@ static int qcow2_change_backing_file(BlockDriverSta= te *bs, return qcow2_update_header(bs); } =20 -static int preallocate(BlockDriverState *bs) +static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_l= ength) { uint64_t bytes; - uint64_t offset; uint64_t host_offset =3D 0; unsigned int cur_bytes; int ret; QCowL2Meta *meta; =20 - bytes =3D bdrv_getlength(bs); - offset =3D 0; + assert(offset <=3D new_length); + bytes =3D new_length - offset; =20 while (bytes) { cur_bytes =3D MIN(bytes, INT_MAX); @@ -2313,7 +2312,7 @@ static int qcow2_create2(const char *filename, int64_= t total_size, if (prealloc !=3D PREALLOC_MODE_OFF) { BDRVQcow2State *s =3D blk_bs(blk)->opaque; qemu_co_mutex_lock(&s->lock); - ret =3D preallocate(blk_bs(blk)); + ret =3D preallocate(blk_bs(blk), 0, total_size); qemu_co_mutex_unlock(&s->lock); if (ret < 0) { error_setg_errno(errp, -ret, "Could not preallocate metadata"); --=20 2.12.0