From nobody Thu Nov 6 03:38:36 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 1539113908663890.7902406564248; Tue, 9 Oct 2018 12:38:28 -0700 (PDT) Received: from localhost ([::1]:53545 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g9xpr-0003SC-Je for importer@patchew.org; Tue, 09 Oct 2018 15:38:27 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59651) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g9xnB-0001b5-Kb for qemu-devel@nongnu.org; Tue, 09 Oct 2018 15:35:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g9xn7-0007Hb-MF for qemu-devel@nongnu.org; Tue, 09 Oct 2018 15:35:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44454) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g9xn5-0007FT-5o; Tue, 09 Oct 2018 15:35:35 -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 7CB675F732; Tue, 9 Oct 2018 19:35:34 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-116-66.ams2.redhat.com [10.36.116.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 09B10600C1; Tue, 9 Oct 2018 19:35:32 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 9 Oct 2018 21:35:23 +0200 Message-Id: <20181009193524.19052-4-kwolf@redhat.com> In-Reply-To: <20181009193524.19052-1-kwolf@redhat.com> References: <20181009193524.19052-1-kwolf@redhat.com> 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 [10.5.110.39]); Tue, 09 Oct 2018 19:35:34 +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 3/4] nbd: 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-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" If read-only=3Doff, but auto-read-only=3Don are given, open a read-write NBD connection if the server provides a read-write export, but instead of erroring out for read-only exports, just degrade to read-only. Signed-off-by: Kevin Wolf --- block/nbd-client.h | 1 + block/nbd-client.c | 14 +++++++++++--- block/nbd.c | 4 +++- 3 files changed, 15 insertions(+), 4 deletions(-) diff --git a/block/nbd-client.h b/block/nbd-client.h index cfc90550b9..1d14e78e92 100644 --- a/block/nbd-client.h +++ b/block/nbd-client.h @@ -46,6 +46,7 @@ int nbd_client_init(BlockDriverState *bs, QCryptoTLSCreds *tlscreds, const char *hostname, const char *x_dirty_bitmap, + bool auto_readonly, Error **errp); void nbd_client_close(BlockDriverState *bs); =20 diff --git a/block/nbd-client.c b/block/nbd-client.c index 9686ecbd5e..6a1e634bec 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -971,6 +971,7 @@ int nbd_client_init(BlockDriverState *bs, QCryptoTLSCreds *tlscreds, const char *hostname, const char *x_dirty_bitmap, + bool auto_readonly, Error **errp) { NBDClientSession *client =3D nbd_get_client_session(bs); @@ -994,9 +995,16 @@ int nbd_client_init(BlockDriverState *bs, } if (client->info.flags & NBD_FLAG_READ_ONLY && !bdrv_is_read_only(bs)) { - error_setg(errp, - "request for write access conflicts with read-only expo= rt"); - return -EACCES; + if (auto_readonly) { + ret =3D bdrv_set_read_only(bs, true, errp); + if (ret < 0) { + return ret; + } + } else { + error_setg(errp, "request for write access conflicts with " + "read-only export"); + return -EACCES; + } } if (client->info.flags & NBD_FLAG_SEND_FUA) { bs->supported_write_flags =3D BDRV_REQ_FUA; diff --git a/block/nbd.c b/block/nbd.c index e87699fb73..8c352a45cd 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -445,7 +445,9 @@ static int nbd_open(BlockDriverState *bs, QDict *option= s, int flags, =20 /* NBD handshake */ ret =3D nbd_client_init(bs, sioc, s->export, tlscreds, hostname, - qemu_opt_get(opts, "x-dirty-bitmap"), errp); + qemu_opt_get(opts, "x-dirty-bitmap"), + (flags & BDRV_O_AUTO_RDONLY), + errp); error: if (sioc) { object_unref(OBJECT(sioc)); --=20 2.13.6