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=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 DD460C433F5 for ; Wed, 15 Sep 2021 08:06:10 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 51CC1611AF for ; Wed, 15 Sep 2021 08:06:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 51CC1611AF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 12A9340287; Wed, 15 Sep 2021 08:06:10 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5igGaxjzKWu8; Wed, 15 Sep 2021 08:06:09 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp4.osuosl.org (Postfix) with ESMTPS id 8AD4F40250; Wed, 15 Sep 2021 08:06:08 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 41CFBC000F; Wed, 15 Sep 2021 08:06:08 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 09F80C000D for ; Wed, 15 Sep 2021 08:06:07 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id DE19D4011C for ; Wed, 15 Sep 2021 08:06:06 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp2.osuosl.org (amavisd-new); dkim=pass (1024-bit key) header.d=redhat.com Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id iWMRpDXNlQ-W for ; Wed, 15 Sep 2021 08:06:04 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by smtp2.osuosl.org (Postfix) with ESMTPS id AAAA7400EE for ; Wed, 15 Sep 2021 08:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631693163; 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: in-reply-to:in-reply-to:references:references; bh=XTJOPOBK2FWoIHtqCxOB4rq1YLQd/kSrktTEId4dfSw=; b=DLavQAQV2UdWt5tgpaEB29kNjgkXyrZ6rcOAUpPLUTswJojrgq0u4DlUW0PaGoNVZvknTL /vI0Jp1ZJ65bNy/6QrQBYuhLNGsi9KTmliWL/V6NfR0If+kTDniCdn7QS1KjXNMtuX/naK cJnZJ1+HhkjFV+36kfYuHA1ECHTxFfQ= Received: from mail-lj1-f198.google.com (mail-lj1-f198.google.com [209.85.208.198]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-503--eWwa4jPO8uj_c_ccEWLEQ-1; Wed, 15 Sep 2021 04:06:01 -0400 X-MC-Unique: -eWwa4jPO8uj_c_ccEWLEQ-1 Received: by mail-lj1-f198.google.com with SMTP id p11-20020a2ea40b000000b001d68cffb055so1123931ljn.6 for ; Wed, 15 Sep 2021 01:06:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=XTJOPOBK2FWoIHtqCxOB4rq1YLQd/kSrktTEId4dfSw=; b=i9lD8OEVlNBZRkIM9UVABDAORNUk43gqONcDOfHm/zijtXOBKeNV3RnYOjFc5LgMw5 FmKPbEvZivCcHthxSH0OfQIci66BLlC8XGtJYvb55CSUo0leGeBSirMRz9dBzzPtcAdC +iZGBG7ykkuuhs5dTins4bHc/tXbmRCFGbw/oSy72m0X6++qh1AbmOLQmpJGlwS7k5IL 7LjqYXbfstj5J9MTLgZzKeqb6thK0A4Rj4gMWGIEJS+8gCzdCC0WvCmKJPj7M+yO68Dv uBaBHOQPZgVh6FmKDidX/LNxIkbe/e+Ipd1PHdwDaq8k8PdTpx5W2ZCdTRPoVUXwa2dF 7/0g== X-Gm-Message-State: AOAM533HBK0kQM1kqicaGJCD0UO/WHoPBnZwqvas3AxLiycv+VciBBfC jhS+q50C4JJgj2XsLK3umi8YDpPcwYcM6xTKeultzNVl/2sad81o2w0xDcg9V7hkdPMLvFqr86e RBGZaQYEPENNQhOWoe/sDZGfuB+un2+u5TYD6/voNkzPcFKNx1J8VZmVEBg== X-Received: by 2002:a05:6512:2254:: with SMTP id i20mr16264812lfu.348.1631693160336; Wed, 15 Sep 2021 01:06:00 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwqrnLiCAjGMSIhm0xEtGCYbTdjLcTMVGgBTxbfAsS5lxuiHGYePOaD1vkjPALPM1IjTYCM6wVKxVBewo2YRgU= X-Received: by 2002:a05:6512:2254:: with SMTP id i20mr16264799lfu.348.1631693160094; Wed, 15 Sep 2021 01:06:00 -0700 (PDT) MIME-Version: 1.0 References: <834528d24c839080215b2e077f100e9ed5073edc.1631621507.git.wuzongyong@linux.alibaba.com> <20210914085711-mutt-send-email-mst@kernel.org> <20210915032453.GA18793@L-PF27918B-1352.localdomain> <20210915032732-mutt-send-email-mst@kernel.org> In-Reply-To: <20210915032732-mutt-send-email-mst@kernel.org> From: Jason Wang Date: Wed, 15 Sep 2021 16:05:49 +0800 Message-ID: Subject: Re: [PATCH v2 4/5] vdpa: add new vdpa attribute VDPA_ATTR_DEV_F_VERSION_1 To: "Michael S. Tsirkin" Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jasowang@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Cc: wei.yang1@linux.alibaba.com, Wu Zongyong , linux-kernel , virtualization X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Wed, Sep 15, 2021 at 3:31 PM Michael S. Tsirkin wrote: > > On Wed, Sep 15, 2021 at 11:24:53AM +0800, Wu Zongyong wrote: > > On Tue, Sep 14, 2021 at 08:58:28AM -0400, Michael S. Tsirkin wrote: > > > On Tue, Sep 14, 2021 at 08:24:51PM +0800, Wu Zongyong wrote: > > > > This new attribute advertises whether the vdpa device is legacy or not. > > > > Users can pick right virtqueue size if the vdpa device is legacy which > > > > doesn't support to change virtqueue size. > > > > > > > > Signed-off-by: Wu Zongyong > > > > > > So if we are bothering with legacy, I think there are > > > several things to do when building the interface > > > - support transitional devices, that is allow userspace > > > to tell device it's in legacy mode > > > - support reporting/setting supporting endian-ness > > > > It's true if we try to implement a general drvier for legacy. > > But this series is dedicated to implement a driver only for ENI. Is it > > necessary to implement what you said here in this series? > > To a certain degree, yes. > > I am thinking about the UAPI here. The new attribute is part of that. > E.g. userspace consuming this needs to be more or less hardware agnostic > and not depend on specifics of ENI. > > Otherwise if userspace assumes legacy==eni then it will break with > other hardware. > > One way to test how generic it all is would be adding legacy support in > the simulator. I don't get why we need to support legacy devices e.g it doesn't have ACCESS_PLATFORM support. I think we should re-consider to mandate 1.0 devices. https://lore.kernel.org/lkml/20210408082648.20145-1-jasowang@redhat.com/ And it will complicate all of the different layers. Thanks > > > > > > > > --- > > > > drivers/vdpa/vdpa.c | 6 ++++++ > > > > drivers/virtio/virtio_vdpa.c | 7 ++++++- > > > > include/uapi/linux/vdpa.h | 1 + > > > > 3 files changed, 13 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c > > > > index 1dc121a07a93..533d7f589eee 100644 > > > > --- a/drivers/vdpa/vdpa.c > > > > +++ b/drivers/vdpa/vdpa.c > > > > @@ -12,6 +12,7 @@ > > > > #include > > > > #include > > > > #include > > > > +#include > > > > #include > > > > #include > > > > > > > > @@ -494,6 +495,7 @@ vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq > > > > u16 max_vq_size; > > > > u32 device_id; > > > > u32 vendor_id; > > > > + u64 features; > > > > void *hdr; > > > > int err; > > > > > > > > @@ -508,6 +510,7 @@ vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq > > > > device_id = vdev->config->get_device_id(vdev); > > > > vendor_id = vdev->config->get_vendor_id(vdev); > > > > max_vq_size = vdev->config->get_vq_num_max(vdev); > > > > + features = vdev->config->get_features(vdev); > > > > > > > > err = -EMSGSIZE; > > > > if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev))) > > > > @@ -520,6 +523,9 @@ vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq > > > > goto msg_err; > > > > if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_VQ_SIZE, max_vq_size)) > > > > goto msg_err; > > > > + if (features & BIT_ULL(VIRTIO_F_VERSION_1) && > > > > + nla_put_flag(msg, VDPA_ATTR_DEV_VERSION_1)) > > > > + goto msg_err; > > > > > > > > genlmsg_end(msg, hdr); > > > > return 0; > > > > diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c > > > > index 72eaef2caeb1..1cba957c4cdc 100644 > > > > --- a/drivers/virtio/virtio_vdpa.c > > > > +++ b/drivers/virtio/virtio_vdpa.c > > > > @@ -7,6 +7,7 @@ > > > > * > > > > */ > > > > > > > > +#include "linux/virtio_config.h" > > > > #include > > > > #include > > > > #include > > > > @@ -145,6 +146,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, > > > > /* Assume split virtqueue, switch to packed if necessary */ > > > > struct vdpa_vq_state state = {0}; > > > > unsigned long flags; > > > > + bool may_reduce_num = false; > > > > u32 align, num; > > > > int err; > > > > > > > > @@ -169,10 +171,13 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, > > > > goto error_new_virtqueue; > > > > } > > > > > > > > + if (ops->get_features(vdpa) & BIT_ULL(VIRTIO_F_VERSION_1)) > > > > + may_reduce_num = true; > > > > + > > > > /* Create the vring */ > > > > align = ops->get_vq_align(vdpa); > > > > vq = vring_create_virtqueue(index, num, align, vdev, > > > > - true, true, ctx, > > > > + true, may_reduce_num, ctx, > > > > virtio_vdpa_notify, callback, name); > > > > if (!vq) { > > > > err = -ENOMEM; > > > > diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h > > > > index 66a41e4ec163..ce0b74276a5b 100644 > > > > --- a/include/uapi/linux/vdpa.h > > > > +++ b/include/uapi/linux/vdpa.h > > > > @@ -32,6 +32,7 @@ enum vdpa_attr { > > > > VDPA_ATTR_DEV_VENDOR_ID, /* u32 */ > > > > VDPA_ATTR_DEV_MAX_VQS, /* u32 */ > > > > VDPA_ATTR_DEV_MAX_VQ_SIZE, /* u16 */ > > > > + VDPA_ATTR_DEV_VERSION_1, /* flag */ > > > > > > > > /* new attributes must be added above here */ > > > > VDPA_ATTR_MAX, > > > > -- > > > > 2.31.1 > _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization