From patchwork Thu Jul 20 14:00:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 13320562 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1FCF0EB64DA for ; Thu, 20 Jul 2023 14:01:58 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qMUD1-0001Rv-UZ; Thu, 20 Jul 2023 10:00:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qMUD1-0001Rl-0F for qemu-devel@nongnu.org; Thu, 20 Jul 2023 10:00:47 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qMUCo-0005V7-Jd for qemu-devel@nongnu.org; Thu, 20 Jul 2023 10:00:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689861631; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=cn9ws6g9BiUBsSv2HMdIOcDrDIn4b6FgSbL0J9YWLYg=; b=X8KAgUkw93v5IMkEC2dc1nbz6LEZxJJCqx9c30ns6es7NrNX0G0P3gmQWpSvZrrB37GTn3 pf2FjY2OJshftjOSWoRh8UsqvzuPIV0CylynCvw95XLBXx7RhMb5dHFXcAL9OB9X0BcR3j oKfy8Vu6/kgBc7PCmIYxVfQ0q1of/z8= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-155-MlI1bSNGMcqTtUrQnDBZgA-1; Thu, 20 Jul 2023 10:00:29 -0400 X-MC-Unique: MlI1bSNGMcqTtUrQnDBZgA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CCFFD3813F41; Thu, 20 Jul 2023 14:00:27 +0000 (UTC) Received: from localhost (unknown [10.39.193.221]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 72079492CAD; Thu, 20 Jul 2023 14:00:27 +0000 (UTC) From: Hanna Czenczek To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Hanna Czenczek , Kevin Wolf Subject: [PATCH] block: Be more verbose in create fallback Date: Thu, 20 Jul 2023 16:00:24 +0200 Message-ID: <20230720140024.46836-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org For image creation code, we have central fallback code for protocols that do not support creating new images (like NBD or iscsi). So for them, you can only specify existing paths/exports that are overwritten to make clean new images. In such a case, if the given path cannot be opened (assuming a pre-existing image there), we print an error message that tries to describe what is going on: That with this protocol, you cannot create new images, but only overwrite existing ones; and the given path could not be opened as a pre-existing image. However, the current message is confusing, because it does not say that the protocol in question does not support creating new images, but instead that "image creation" is unsupported. This can be interpreted to mean that `qemu-img create` will not work in principle, which is not true. Be more verbose for clarity. Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2217204 Signed-off-by: Hanna Czenczek Reviewed-by: Eric Blake --- block.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index a307c151a8..f530dd9c02 100644 --- a/block.c +++ b/block.c @@ -661,8 +661,10 @@ int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv, blk = blk_co_new_open(filename, NULL, options, BDRV_O_RDWR | BDRV_O_RESIZE, errp); if (!blk) { - error_prepend(errp, "Protocol driver '%s' does not support image " - "creation, and opening the image failed: ", + error_prepend(errp, "Protocol driver '%s' does not support creating " + "new images, so an existing image must be selected as " + "the target; however, opening the given target as an " + "existing image failed: ", drv->format_name); return -EINVAL; }