From patchwork Wed Jun 2 02:10:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 12292641 X-Patchwork-Delegate: kuba@kernel.org 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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 A6464C4708F for ; Wed, 2 Jun 2021 02:11:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92EAA610CB for ; Wed, 2 Jun 2021 02:11:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229932AbhFBCMx (ORCPT ); Tue, 1 Jun 2021 22:12:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42626 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230341AbhFBCMq (ORCPT ); Tue, 1 Jun 2021 22:12:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622599863; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xpp86MKQOz0QZsgGameycFz6/zr05nCyS0wGULJidQo=; b=jOyoBlAPxrwh67jWi66FV2T5VIj/2OYnjmNUhEE5kv9PD6r3ciLB5ckbqdKCkrow/o+7iD VzfwQnzG+s91BINxFnUe6BtnDNUoZPvCwAt2EAsXAcWfuyp1vyBoXvOYmbWPHbAb3+eJXN mKlC981pcBlIT8weWHM/6O8C4rHktvo= 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-559-a1fIgH-tN0WREjueqphQag-1; Tue, 01 Jun 2021 22:11:00 -0400 X-MC-Unique: a1fIgH-tN0WREjueqphQag-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1BDFB501E1; Wed, 2 Jun 2021 02:10:59 +0000 (UTC) Received: from localhost.localdomain (ovpn-12-99.pek2.redhat.com [10.72.12.99]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9FA2C5D6CF; Wed, 2 Jun 2021 02:10:56 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, netdev@vger.kernel.org Cc: eli@mellanox.com Subject: [PATCH V2 2/4] virtio-pci library: introduce vp_modern_get_driver_features() Date: Wed, 2 Jun 2021 10:10:41 +0800 Message-Id: <20210602021043.39201-3-jasowang@redhat.com> In-Reply-To: <20210602021043.39201-1-jasowang@redhat.com> References: <20210602021043.39201-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch introduce a helper to get driver/guest features from the device. Signed-off-by: Jason Wang --- drivers/virtio/virtio_pci_modern_dev.c | 21 +++++++++++++++++++++ include/linux/virtio_pci_modern.h | 1 + 2 files changed, 22 insertions(+) diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c index 54f297028586..e11ed748e661 100644 --- a/drivers/virtio/virtio_pci_modern_dev.c +++ b/drivers/virtio/virtio_pci_modern_dev.c @@ -383,6 +383,27 @@ u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev) } EXPORT_SYMBOL_GPL(vp_modern_get_features); +/* + * vp_modern_get_driver_features - get driver features from device + * @mdev: the modern virtio-pci device + * + * Returns the driver features read from the device + */ +u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_common_cfg __iomem *cfg = mdev->common; + + u64 features; + + vp_iowrite32(0, &cfg->guest_feature_select); + features = vp_ioread32(&cfg->guest_feature); + vp_iowrite32(1, &cfg->guest_feature_select); + features |= ((u64)vp_ioread32(&cfg->guest_feature) << 32); + + return features; +} +EXPORT_SYMBOL_GPL(vp_modern_get_driver_features); + /* * vp_modern_set_features - set features to device * @mdev: the modern virtio-pci device diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h index 6a95b58fd0f4..eb2bd9b4077d 100644 --- a/include/linux/virtio_pci_modern.h +++ b/include/linux/virtio_pci_modern.h @@ -79,6 +79,7 @@ static inline void vp_iowrite64_twopart(u64 val, } u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev); +u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev); void vp_modern_set_features(struct virtio_pci_modern_device *mdev, u64 features); u32 vp_modern_generation(struct virtio_pci_modern_device *mdev);