From nobody Thu Nov 6 08:24:11 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 1539795029573435.04754132554785; Wed, 17 Oct 2018 09:50:29 -0700 (PDT) Received: from localhost ([::1]:38156 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gCp1g-0005P1-Cn for importer@patchew.org; Wed, 17 Oct 2018 12:50:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44878) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gCouJ-00072x-K1 for qemu-devel@nongnu.org; Wed, 17 Oct 2018 12:42:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gCouG-00041A-EO for qemu-devel@nongnu.org; Wed, 17 Oct 2018 12:42:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35300) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gCou9-0002cn-Mi; Wed, 17 Oct 2018 12:42:42 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B236730B8FB9; Wed, 17 Oct 2018 16:42:14 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-213.ams2.redhat.com [10.36.117.213]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4CB5760160; Wed, 17 Oct 2018 16:42:13 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Wed, 17 Oct 2018 18:41:56 +0200 Message-Id: <20181017164200.22344-6-kwolf@redhat.com> In-Reply-To: <20181017164200.22344-1-kwolf@redhat.com> References: <20181017164200.22344-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Wed, 17 Oct 2018 16:42:14 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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 v3 5/9] file-posix: Support auto-read-only option 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, pkrempa@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RDMRC_1 RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" If read-only=3Doff, but auto-read-only=3Don is given, open the file read-write if we have the permissions, but instead of erroring out for read-only files, just degrade to read-only. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake --- block/file-posix.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 2da3a76355..0c1b81ce4b 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -527,9 +527,22 @@ static int raw_open_common(BlockDriverState *bs, QDict= *options, =20 s->fd =3D -1; fd =3D qemu_open(filename, s->open_flags, 0644); - if (fd < 0) { - ret =3D -errno; - error_setg_errno(errp, errno, "Could not open '%s'", filename); + ret =3D fd < 0 ? -errno : 0; + + if (ret =3D=3D -EACCES || ret =3D=3D -EROFS) { + /* Try to degrade to read-only, but if it doesn't work, still use = the + * normal error message. */ + if (bdrv_apply_auto_read_only(bs, NULL, NULL) =3D=3D 0) { + bdrv_flags &=3D ~BDRV_O_RDWR; + raw_parse_flags(bdrv_flags, &s->open_flags); + assert(!(s->open_flags & O_CREAT)); + fd =3D qemu_open(filename, s->open_flags); + ret =3D fd < 0 ? -errno : 0; + } + } + + if (ret < 0) { + error_setg_errno(errp, -ret, "Could not open '%s'", filename); if (ret =3D=3D -EROFS) { ret =3D -EACCES; } --=20 2.19.1