From patchwork Fri Oct 12 11:55:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 983017 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42Wmbl3pRGz9s1x for ; Fri, 12 Oct 2018 22:59:47 +1100 (AEDT) Received: from localhost ([::1]:39680 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gAw6b-0001lw-3r for incoming@patchwork.ozlabs.org; Fri, 12 Oct 2018 07:59:45 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38020) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gAw2x-0007eV-0t for qemu-devel@nongnu.org; Fri, 12 Oct 2018 07:56:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gAw2w-0005vu-7M for qemu-devel@nongnu.org; Fri, 12 Oct 2018 07:55:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38380) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gAw2r-0005hz-9t; Fri, 12 Oct 2018 07:55:53 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4DC86C04BD47; Fri, 12 Oct 2018 11:55:52 +0000 (UTC) Received: from dhcp-200-186.str.redhat.com (dhcp-200-186.str.redhat.com [10.33.200.186]) by smtp.corp.redhat.com (Postfix) with ESMTP id 05B3C6F110; Fri, 12 Oct 2018 11:55:50 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Fri, 12 Oct 2018 13:55:28 +0200 Message-Id: <20181012115532.12645-5-kwolf@redhat.com> In-Reply-To: <20181012115532.12645-1-kwolf@redhat.com> References: <20181012115532.12645-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Fri, 12 Oct 2018 11:55:52 +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 4/8] 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" If read-only=off, but auto-read-only=on is 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 Reviewed-by: Eric Blake --- block/nbd-client.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 9686ecbd5e..76e9ca3abe 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -992,11 +992,11 @@ int nbd_client_init(BlockDriverState *bs, logout("Failed to negotiate with the NBD server\n"); return ret; } - if (client->info.flags & NBD_FLAG_READ_ONLY && - !bdrv_is_read_only(bs)) { - error_setg(errp, - "request for write access conflicts with read-only export"); - return -EACCES; + if (client->info.flags & NBD_FLAG_READ_ONLY) { + ret = bdrv_apply_auto_read_only(bs, "NBD export is read-only", errp); + if (ret < 0) { + return ret; + } } if (client->info.flags & NBD_FLAG_SEND_FUA) { bs->supported_write_flags = BDRV_REQ_FUA;