From patchwork Fri May 29 16:13:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 11579283 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ED31B1391 for ; Fri, 29 May 2020 16:14:46 +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 82DCE20897 for ; Fri, 29 May 2020 16:14:46 +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="hOapio/+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82DCE20897 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:46060 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jehef-0007QK-CX for patchwork-qemu-devel@patchwork.kernel.org; Fri, 29 May 2020 12:14:45 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55886) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jehdt-0006uE-19 for qemu-devel@nongnu.org; Fri, 29 May 2020 12:13:57 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:42638 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 1jehdr-00028R-Mp for qemu-devel@nongnu.org; Fri, 29 May 2020 12:13:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590768834; 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=6dFsTSQtluTSTZuB0y/nh90yEdfmymhfTWqxDXaKFLk=; b=hOapio/+jBkYTfIwRFl2TUVOEQQwXo1J05NQp0HDh1yK1zQPds0nT/51j1ln9j6HE7eeJz XzfNzddpR497MSe4mIS4QuneyE/V33W+WTPxLbJvI6LWPutOESGqbegBp39uNH/94xXgaz teT7KdQhmI26M0E95QafyAO37SToOHI= 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-459-dDalw0wzM8m24kPnwxJ_SQ-1; Fri, 29 May 2020 12:13:52 -0400 X-MC-Unique: dDalw0wzM8m24kPnwxJ_SQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3BDFAEC1B8; Fri, 29 May 2020 16:13:51 +0000 (UTC) Received: from localhost (ovpn-114-38.ams2.redhat.com [10.36.114.38]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9DC997A8D3; Fri, 29 May 2020 16:13:39 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH] libvhost-user: advertise vring features Date: Fri, 29 May 2020 17:13:38 +0100 Message-Id: <20200529161338.456017-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.81; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/29 01:27:49 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] 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, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN 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: =?utf-8?q?Marc-Andr=C3=A9_Lureau?= , Jason Wang , "Michael S. Tsirkin" , Stefan Hajnoczi , Raphael Norwitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" libvhost-user implements several vring features without advertising them. There is no way for the vhost-user master to detect support for these features. Things more or less work today because QEMU assumes the vhost-user backend always implements certain feature bits like VIRTIO_RING_F_EVENT_IDX. This is not documented anywhere. This patch explicitly advertises features implemented in libvhost-user so that the vhost-user master does not need to make undocumented assumptions. Feature bits that libvhost-user now advertises can be removed from vhost-user-blk.c. Devices should not be responsible for advertising vring feature bits, that is libvhost-user's job. Cc: Marc-André Lureau Cc: Jason Wang Cc: Michael S. Tsirkin Signed-off-by: Stefan Hajnoczi Reviewed-by: Marc-André Lureau --- I have tested make check and virtiofsd. --- contrib/libvhost-user/libvhost-user.c | 10 ++++++++++ contrib/vhost-user-blk/vhost-user-blk.c | 4 +--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index 3bca996c62..b43874ba12 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -495,6 +495,16 @@ static bool vu_get_features_exec(VuDev *dev, VhostUserMsg *vmsg) { vmsg->payload.u64 = + /* + * The following VIRTIO feature bits are supported by our virtqueue + * implementation: + */ + 1ULL << VIRTIO_F_NOTIFY_ON_EMPTY | + 1ULL << VIRTIO_RING_F_INDIRECT_DESC | + 1ULL << VIRTIO_RING_F_EVENT_IDX | + 1ULL << VIRTIO_F_VERSION_1 | + + /* vhost-user feature bits */ 1ULL << VHOST_F_LOG_ALL | 1ULL << VHOST_USER_F_PROTOCOL_FEATURES; diff --git a/contrib/vhost-user-blk/vhost-user-blk.c b/contrib/vhost-user-blk/vhost-user-blk.c index 6fd91c7e99..25eccd02b5 100644 --- a/contrib/vhost-user-blk/vhost-user-blk.c +++ b/contrib/vhost-user-blk/vhost-user-blk.c @@ -382,9 +382,7 @@ vub_get_features(VuDev *dev) 1ull << VIRTIO_BLK_F_DISCARD | 1ull << VIRTIO_BLK_F_WRITE_ZEROES | #endif - 1ull << VIRTIO_BLK_F_CONFIG_WCE | - 1ull << VIRTIO_F_VERSION_1 | - 1ull << VHOST_USER_F_PROTOCOL_FEATURES; + 1ull << VIRTIO_BLK_F_CONFIG_WCE; if (vdev_blk->enable_ro) { features |= 1ull << VIRTIO_BLK_F_RO;