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=-18.7 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,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 BDE80C63777 for ; Mon, 30 Nov 2020 03:27:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4EC6D2222C for ; Mon, 30 Nov 2020 03:27:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FbTyj6CQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728586AbgK3D1M (ORCPT ); Sun, 29 Nov 2020 22:27:12 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:26982 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727156AbgK3D1M (ORCPT ); Sun, 29 Nov 2020 22:27:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606706745; 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=PKqxfTAarK2PmpFylMjiQ+MEy5YRoBV5xq5ZWEkarc0=; b=FbTyj6CQphG1Zdkly9plqy8glBzJqi28a+iAxlWw0Gcjo6phMnEiWgntos+U3R7+17i6Zp DL4TA6BiaTDmYIZ7Eza0jhZd5qfWgk/midw157q8uBm/M13bZ7nYS0zpCajyNk1UsDqKu2 t3GSZ2ynyUvUllzvlagOhpkQjuMAfq4= 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-252-Njj5YyWEPbqqoyyntToa0g-1; Sun, 29 Nov 2020 22:25:42 -0500 X-MC-Unique: Njj5YyWEPbqqoyyntToa0g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A22371005D65; Mon, 30 Nov 2020 03:25:41 +0000 (UTC) Received: from [10.72.13.173] (ovpn-13-173.pek2.redhat.com [10.72.13.173]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2D96B60843; Mon, 30 Nov 2020 03:25:32 +0000 (UTC) Subject: Re: [PATCH v2 12/17] vdpa_sim: add get_config callback in vdpasim_dev_attr To: Stefano Garzarella , virtualization@lists.linux-foundation.org Cc: Stefan Hajnoczi , linux-kernel@vger.kernel.org, Laurent Vivier , Max Gurtovoy , "Michael S. Tsirkin" , Eli Cohen References: <20201126144950.92850-1-sgarzare@redhat.com> <20201126144950.92850-13-sgarzare@redhat.com> From: Jason Wang Message-ID: Date: Mon, 30 Nov 2020 11:25:31 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201126144950.92850-13-sgarzare@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/11/26 下午10:49, Stefano Garzarella wrote: > The get_config callback can be used by the device to fill the > config structure. > The callback will be invoked in vdpasim_get_config() before copying > bytes into caller buffer. > > Move vDPA-net config updates from vdpasim_set_features() in the > new vdpasim_net_get_config() callback. > > Signed-off-by: Stefano Garzarella > --- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 33 +++++++++++++++++++------------- > 1 file changed, 20 insertions(+), 13 deletions(-) > > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c > index c07ddf6af720..8b87ce0485b6 100644 > --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > @@ -58,6 +58,8 @@ struct vdpasim_virtqueue { > #define VDPASIM_NET_FEATURES (VDPASIM_FEATURES | \ > (1ULL << VIRTIO_NET_F_MAC)) > > +struct vdpasim; > + > struct vdpasim_dev_attr { > u64 supported_features; > size_t config_size; > @@ -65,6 +67,7 @@ struct vdpasim_dev_attr { > u32 id; > > work_func_t work_fn; > + void (*get_config)(struct vdpasim *vdpasim, void *config); > }; > > /* State of each vdpasim device */ > @@ -520,8 +523,6 @@ static u64 vdpasim_get_features(struct vdpa_device *vdpa) > static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features) > { > struct vdpasim *vdpasim = vdpa_to_sim(vdpa); > - struct virtio_net_config *config = > - (struct virtio_net_config *)vdpasim->config; > > /* DMA mapping must be done by driver */ > if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) > @@ -529,15 +530,6 @@ static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features) > > vdpasim->features = features & vdpasim->dev_attr.supported_features; > > - /* We generally only know whether guest is using the legacy interface > - * here, so generally that's the earliest we can set config fields. > - * Note: We actually require VIRTIO_F_ACCESS_PLATFORM above which > - * implies VIRTIO_F_VERSION_1, but let's not try to be clever here. > - */ > - > - config->mtu = cpu_to_vdpasim16(vdpasim, 1500); > - config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP); > - memcpy(config->mac, macaddr_buf, ETH_ALEN); > > return 0; > } > @@ -593,8 +585,12 @@ static void vdpasim_get_config(struct vdpa_device *vdpa, unsigned int offset, > { > struct vdpasim *vdpasim = vdpa_to_sim(vdpa); > > - if (offset + len < vdpasim->dev_attr.config_size) > - memcpy(buf, vdpasim->config + offset, len); > + if (offset + len > vdpasim->dev_attr.config_size) > + return; > + > + vdpasim->dev_attr.get_config(vdpasim, vdpasim->config); > + > + memcpy(buf, vdpasim->config + offset, len); > } I wonder how much value we can get from vdpasim->config consider we've already had get_config() method. Is it possible to copy to the buffer directly here? Thanks > > static void vdpasim_set_config(struct vdpa_device *vdpa, unsigned int offset, > @@ -737,6 +733,16 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = { > .free = vdpasim_free, > }; > > +static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config) > +{ > + struct virtio_net_config *net_config = > + (struct virtio_net_config *)config; > + > + net_config->mtu = cpu_to_vdpasim16(vdpasim, 1500); > + net_config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP); > + memcpy(net_config->mac, macaddr_buf, ETH_ALEN); > +} > + > static int __init vdpasim_dev_init(void) > { > struct vdpasim_dev_attr dev_attr = {}; > @@ -745,6 +751,7 @@ static int __init vdpasim_dev_init(void) > dev_attr.supported_features = VDPASIM_NET_FEATURES; > dev_attr.nvqs = VDPASIM_VQ_NUM; > dev_attr.config_size = sizeof(struct virtio_net_config); > + dev_attr.get_config = vdpasim_net_get_config; > dev_attr.work_fn = vdpasim_net_work; > > vdpasim_dev = vdpasim_create(&dev_attr);