From patchwork Tue Oct 7 14:40:01 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cornelia Huck X-Patchwork-Id: 5048451 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 60B1D9F295 for ; Tue, 7 Oct 2014 19:06:34 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 902CB20117 for ; Tue, 7 Oct 2014 19:06:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B47FB200F4 for ; Tue, 7 Oct 2014 19:06:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754811AbaJGTG3 (ORCPT ); Tue, 7 Oct 2014 15:06:29 -0400 Received: from e06smtp12.uk.ibm.com ([195.75.94.108]:44174 "EHLO e06smtp12.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754325AbaJGTG3 (ORCPT ); Tue, 7 Oct 2014 15:06:29 -0400 Received: from /spool/local by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 7 Oct 2014 18:51:55 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by d06dlp02.portsmouth.uk.ibm.com (Postfix) with ESMTP id A73083988E8 for ; Tue, 7 Oct 2014 15:40:26 +0100 (BST) Received: from d06av08.portsmouth.uk.ibm.com (d06av08.portsmouth.uk.ibm.com [9.149.37.249]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id s97EeLtd23986216 for ; Tue, 7 Oct 2014 14:40:28 GMT Received: from d06av08.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av08.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s97EeGej000933 for ; Tue, 7 Oct 2014 08:40:17 -0600 Received: from gondolin.boeblingen.de.ibm.com (dyn-9-152-224-210.boeblingen.de.ibm.com [9.152.224.210]) by d06av08.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id s97EeC4A000717; Tue, 7 Oct 2014 08:40:16 -0600 From: Cornelia Huck To: virtualization@lists.linux-foundation.org, qemu-devel@nongnu.org, kvm@vger.kernel.org Cc: rusty@rustcorp.com.au, thuth@linux.vnet.ibm.com, Cornelia Huck Subject: [PATCH RFC 05/11] virtio: introduce legacy virtio devices Date: Tue, 7 Oct 2014 16:40:01 +0200 Message-Id: <1412692807-12398-6-git-send-email-cornelia.huck@de.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1412692807-12398-1-git-send-email-cornelia.huck@de.ibm.com> References: <1412692807-12398-1-git-send-email-cornelia.huck@de.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14100717-8372-0000-0000-000001741ACB Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduce a helper function to indicate whether a virtio device is operating in legacy or virtio standard mode. It may be used to make decisions about the endianess of virtio accesses and other virtio-1 specific changes, enabling us to support transitional devices. Reviewed-by: Thomas Huth Signed-off-by: Cornelia Huck --- hw/virtio/virtio.c | 6 +++++- include/hw/virtio/virtio-access.h | 4 ++++ include/hw/virtio/virtio.h | 13 +++++++++++-- 3 files changed, 20 insertions(+), 3 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 7aaa953..e6ae3a0 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -883,7 +883,11 @@ static bool virtio_device_endian_needed(void *opaque) VirtIODevice *vdev = opaque; assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN); - return vdev->device_endian != virtio_default_endian(); + if (virtio_device_is_legacy(vdev)) { + return vdev->device_endian != virtio_default_endian(); + } + /* Devices conforming to VIRTIO 1.0 or later are always LE. */ + return vdev->device_endian != VIRTIO_DEVICE_ENDIAN_LITTLE; } static const VMStateDescription vmstate_virtio_device_endian = { diff --git a/include/hw/virtio/virtio-access.h b/include/hw/virtio/virtio-access.h index 46456fd..c123ee0 100644 --- a/include/hw/virtio/virtio-access.h +++ b/include/hw/virtio/virtio-access.h @@ -19,6 +19,10 @@ static inline bool virtio_access_is_big_endian(VirtIODevice *vdev) { + if (!virtio_device_is_legacy(vdev)) { + /* Devices conforming to VIRTIO 1.0 or later are always LE. */ + return false; + } #if defined(TARGET_IS_BIENDIAN) return virtio_is_big_endian(vdev); #elif defined(TARGET_WORDS_BIGENDIAN) diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index b408166..40e567c 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -275,9 +275,18 @@ void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign, void virtio_queue_notify_vq(VirtQueue *vq); void virtio_irq(VirtQueue *vq); +static inline bool virtio_device_is_legacy(VirtIODevice *vdev) +{ + return !(vdev->guest_features[1] & (1 << (VIRTIO_F_VERSION_1 - 32))); +} + static inline bool virtio_is_big_endian(VirtIODevice *vdev) { - assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN); - return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; + if (virtio_device_is_legacy(vdev)) { + assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN); + return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; + } + /* Devices conforming to VIRTIO 1.0 or later are always LE. */ + return false; } #endif