From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83D4DC433E0 for ; Tue, 19 Jan 2021 15:05:30 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 01B1F2250E for ; Tue, 19 Jan 2021 15:05:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 01B1F2250E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42484 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l1sZU-0004PZ-Lk for qemu-devel@archiver.kernel.org; Tue, 19 Jan 2021 10:05:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50698) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l1sXu-0003pi-Bi for qemu-devel@nongnu.org; Tue, 19 Jan 2021 10:03:50 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:59638) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l1sXr-0008Lo-OZ for qemu-devel@nongnu.org; Tue, 19 Jan 2021 10:03:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611068625; 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: in-reply-to:in-reply-to:references:references; bh=9ft4/oz3h85Tjw3wjj+Bry9SSF0uTGOUJcNx6DDFl1Y=; b=SXtr5zcMHYgDpwUfbyzj7QS3v0CDl494E3Ug0byVrAFFIuXbs5lNVbvhpeSpNCXtv+8Dm7 YFo9q2dbrr7fSPqKmJ9ga7CU/ADMzydQuI7aYEtxJQ6WWxBO0CQqfdNUsQvGdpFhHXning J0tKcEoPp0vkLh8FiYA8JVhrBV0K3lU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-329-j_mg_xoLNLCUqsJ1pWNwEw-1; Tue, 19 Jan 2021 10:03:42 -0500 X-MC-Unique: j_mg_xoLNLCUqsJ1pWNwEw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 33B2E107AD26; Tue, 19 Jan 2021 15:03:41 +0000 (UTC) Received: from dresden.str.redhat.com (ovpn-115-54.ams2.redhat.com [10.36.115.54]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4917910021AA; Tue, 19 Jan 2021 15:03:40 +0000 (UTC) Subject: Re: [PATCH 1/2] block: Separate blk_is_writable() and blk_supports_write_perm() To: Kevin Wolf , qemu-block@nongnu.org References: <20210118123448.307825-1-kwolf@redhat.com> <20210118123448.307825-2-kwolf@redhat.com> From: Max Reitz Message-ID: <50412fcb-08e6-699b-1b11-f618bafaee67@redhat.com> Date: Tue, 19 Jan 2021 16:03:38 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20210118123448.307825-2-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.195, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alxndr@bu.edu, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 18.01.21 13:34, Kevin Wolf wrote: > Currently, blk_is_read_only() tells whether a given BlockBackend can > only be used in read-only mode because its root node is read-only. Some > callers actually try to answer a slightly different question: Is the > BlockBackend configured to be writable, by taking write permissions on > the root node? > > This can differ, for example, for CD-ROM devices which don't take write > permissions, but may be backed by a writable image file. scsi-cd allows > write requests to the drive if blk_is_read_only() returns false. > However, the write request will immediately run into an assertion > failure because the write permission is missing. > > This patch introduces separate functions for both questions. > blk_supports_write_perm() answers the question whether the block > node/image file can support writable devices, whereas blk_is_writable() > tells whether the BlockBackend is currently configured to be writable. > > All calls of blk_is_read_only() are converted to one of the two new > functions. > > Fixes: https://bugs.launchpad.net/bugs/1906693 > Cc: qemu-stable@nongnu.org > Signed-off-by: Kevin Wolf > --- > include/sysemu/block-backend.h | 3 ++- > block/block-backend.c | 19 ++++++++++++++++--- > hw/block/dataplane/xen-block.c | 2 +- > hw/block/fdc.c | 9 +++++---- > hw/block/m25p80.c | 6 +++--- > hw/block/nand.c | 2 +- > hw/block/nvme-ns.c | 7 ++++--- > hw/block/onenand.c | 2 +- > hw/block/pflash_cfi01.c | 2 +- > hw/block/pflash_cfi02.c | 2 +- > hw/block/swim.c | 6 +++--- > hw/block/virtio-blk.c | 6 +++--- > hw/block/xen-block.c | 2 +- > hw/ide/core.c | 2 +- > hw/misc/sifive_u_otp.c | 2 +- > hw/ppc/pnv_pnor.c | 2 +- > hw/scsi/scsi-disk.c | 10 +++++----- > hw/scsi/scsi-generic.c | 4 ++-- > hw/sd/sd.c | 6 +++--- > hw/usb/dev-storage.c | 4 ++-- > 20 files changed, 57 insertions(+), 41 deletions(-) Reviewed-by: Max Reitz