From nobody Fri Oct 24 22:13:26 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 1519223113657983.5284486663562; Wed, 21 Feb 2018 06:25:13 -0800 (PST) Received: from localhost ([::1]:32950 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eoVKa-0001cq-JC for importer@patchew.org; Wed, 21 Feb 2018 09:25:12 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38637) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eoUs1-0001bb-Vh for qemu-devel@nongnu.org; Wed, 21 Feb 2018 08:55:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eoUry-0003A5-4K for qemu-devel@nongnu.org; Wed, 21 Feb 2018 08:55:42 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57948 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eoUrv-00038E-KL; Wed, 21 Feb 2018 08:55:35 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A5FBC81A8EB4; Wed, 21 Feb 2018 13:55:34 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-57.ams2.redhat.com [10.36.117.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id 193A72024CAE; Wed, 21 Feb 2018 13:55:32 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Wed, 21 Feb 2018 14:54:01 +0100 Message-Id: <20180221135404.27598-34-kwolf@redhat.com> In-Reply-To: <20180221135404.27598-1-kwolf@redhat.com> References: <20180221135404.27598-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Wed, 21 Feb 2018 13:55:34 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Wed, 21 Feb 2018 13:55:34 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kwolf@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v2 33/36] file-posix: Fix no-op bdrv_truncate() with falloc preallocation 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, jdurgin@redhat.com, pkrempa@redhat.com, mitake.hitoshi@lab.ntt.co.jp, jcody@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com, namei.unix@gmail.com 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" If bdrv_truncate() is called, but the requested size is the same as before, don't call posix_fallocate(), which returns -EINVAL for length zero and would therefore make bdrv_truncate() fail. The problem can be triggered by creating a zero-sized raw image with 'falloc' preallocation mode. Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz Reviewed-by: Eric Blake --- block/file-posix.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index ba14ed9459..6aed5bca0b 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1686,11 +1686,15 @@ static int raw_regular_truncate(int fd, int64_t off= set, PreallocMode prealloc, * file systems that do not support fallocate(), trying to check i= f a * block is allocated before allocating it, so don't do that here. */ - result =3D -posix_fallocate(fd, current_length, offset - current_l= ength); - if (result !=3D 0) { - /* posix_fallocate() doesn't set errno. */ - error_setg_errno(errp, -result, - "Could not preallocate new data"); + if (offset !=3D current_length) { + result =3D -posix_fallocate(fd, current_length, offset - curre= nt_length); + if (result !=3D 0) { + /* posix_fallocate() doesn't set errno. */ + error_setg_errno(errp, -result, + "Could not preallocate new data"); + } + } else { + result =3D 0; } goto out; #endif --=20 2.13.6