From patchwork Wed Sep 16 09:51:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 273587 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 60CC8C433E2 for ; Wed, 16 Sep 2020 09:56:36 +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 A821F21973 for ; Wed, 16 Sep 2020 09:56:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="f5hMZsOe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A821F21973 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]:60640 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kIUAr-0003i1-Ox for qemu-devel@archiver.kernel.org; Wed, 16 Sep 2020 05:56:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53804) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kIU6x-0006JE-6i for qemu-devel@nongnu.org; Wed, 16 Sep 2020 05:52:23 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:30968 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kIU6v-0000eC-Fr for qemu-devel@nongnu.org; Wed, 16 Sep 2020 05:52:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600249940; 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=MXsIGqRE07bfYc36CHCsPlQ1Vpqma7Ye5JadMeb6sv4=; b=f5hMZsOevlHDyIMCmCHNFqBXR8zypkKyMWrOwbrmnxajCadYP8ygkjW3NPAGYxTzOqgceh cXPxZ6spedp0KlkhvcZ6fE2jV2HqdAyn27ND/gFYWAWNHeNT6zaZKYxklWD+pAYhhgTPSi 2VEQDl65MGninETmBSOq34XRoCPzwPQ= 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-504-0jd0sEcGP2iZFE3-TL3QBQ-1; Wed, 16 Sep 2020 05:52:16 -0400 X-MC-Unique: 0jd0sEcGP2iZFE3-TL3QBQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B5F48107464B; Wed, 16 Sep 2020 09:52:15 +0000 (UTC) Received: from localhost (ovpn-115-47.ams2.redhat.com [10.36.115.47]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5A66260BFA; Wed, 16 Sep 2020 09:52:15 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH v2 3/3] nvdimm: honor -object memory-backend-file, readonly=on option Date: Wed, 16 Sep 2020 10:51:50 +0100 Message-Id: <20200916095150.755714-4-stefanha@redhat.com> In-Reply-To: <20200916095150.755714-1-stefanha@redhat.com> References: <20200916095150.755714-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0.003 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/16 00:53:39 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -50 X-Spam_score: -5.1 X-Spam_bar: ----- X-Spam_report: (-5.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.999, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-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: Eduardo Habkost , "Michael S. Tsirkin" , Julio Montes , Xiao Guangrong , eric.g.ernst@gmail.com, Stefan Hajnoczi , Igor Mammedov , Paolo Bonzini , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Make it possible to present read-only files to the guest as "unarmed" NVDIMMs. The Linux NVDIMM device (/dev/pmemX) is read-only. Acked-by: Michael S. Tsirkin Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Stefan Hajnoczi --- docs/nvdimm.txt | 8 +++++++- hw/mem/nvdimm.c | 4 ++++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/docs/nvdimm.txt b/docs/nvdimm.txt index c2c6e441b3..06c2008107 100644 --- a/docs/nvdimm.txt +++ b/docs/nvdimm.txt @@ -17,7 +17,7 @@ following command line options: -machine pc,nvdimm -m $RAM_SIZE,slots=$N,maxmem=$MAX_SIZE - -object memory-backend-file,id=mem1,share=on,mem-path=$PATH,size=$NVDIMM_SIZE + -object memory-backend-file,id=mem1,share=on,mem-path=$PATH,size=$NVDIMM_SIZE,readonly=off -device nvdimm,id=nvdimm1,memdev=mem1 Where, @@ -42,6 +42,12 @@ Where, "share=off", then guest writes won't be applied to the backend file and thus will be invisible to other guests. + "readonly=on/off" controls whether the file $PATH is opened read-only or + read/write (default). "readonly=on" sets the ACPI NFIT NVDIMM Region Mapping + Structure "NVDIMM State Flags" Bit 3 indicating that the device is "unarmed" + and cannot accept persistent writes. Linux guest drivers set the device to + read-only when this bit is present. + - "device nvdimm,id=nvdimm1,memdev=mem1" creates a virtual NVDIMM device whose storage is provided by above memory backend device. diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c index e1574bc07c..848cd65917 100644 --- a/hw/mem/nvdimm.c +++ b/hw/mem/nvdimm.c @@ -146,6 +146,10 @@ static void nvdimm_prepare_memory_region(NVDIMMDevice *nvdimm, Error **errp) return; } + if (memory_region_is_rom(mr)) { + nvdimm->unarmed = true; /* this device is read-only */ + } + nvdimm->nvdimm_mr = g_new(MemoryRegion, 1); memory_region_init_alias(nvdimm->nvdimm_mr, OBJECT(dimm), "nvdimm-memory", mr, 0, pmem_size);