From patchwork Thu Dec 15 13:49:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhijian Li (Fujitsu)\" via" X-Patchwork-Id: 13074243 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id F347BC4167B for ; Thu, 15 Dec 2022 13:50:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p5od5-00006k-6k; Thu, 15 Dec 2022 08:50:31 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5od0-00005f-PD for qemu-devel@nongnu.org; Thu, 15 Dec 2022 08:50:26 -0500 Received: from szxga02-in.huawei.com ([45.249.212.188]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5ocy-0003PK-JJ for qemu-devel@nongnu.org; Thu, 15 Dec 2022 08:50:26 -0500 Received: from kwepemi100025.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4NXtr76ZptzRq4K; Thu, 15 Dec 2022 21:49:11 +0800 (CST) Received: from DESKTOP-27KDQMV.china.huawei.com (10.174.148.223) by kwepemi100025.china.huawei.com (7.221.188.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Thu, 15 Dec 2022 21:50:13 +0800 To: , , , CC: , , , , , , Longpeng Subject: [PATCH v11 5/5] docs: Add generic vhost-vdpa device documentation Date: Thu, 15 Dec 2022 21:49:44 +0800 Message-ID: <20221215134944.2809-6-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 In-Reply-To: <20221215134944.2809-1-longpeng2@huawei.com> References: <20221215134944.2809-1-longpeng2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.148.223] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemi100025.china.huawei.com (7.221.188.158) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.188; envelope-from=longpeng2@huawei.com; helo=szxga02-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: "Longpeng(Mike)" X-Patchwork-Original-From: "Longpeng(Mike)" via From: "Zhijian Li (Fujitsu)\" via" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Longpeng Signed-off-by: Longpeng Acked-by: Jason Wang --- .../devices/vhost-vdpa-generic-device.rst | 68 +++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 docs/system/devices/vhost-vdpa-generic-device.rst diff --git a/docs/system/devices/vhost-vdpa-generic-device.rst b/docs/system/devices/vhost-vdpa-generic-device.rst new file mode 100644 index 0000000000..24c825ef1a --- /dev/null +++ b/docs/system/devices/vhost-vdpa-generic-device.rst @@ -0,0 +1,68 @@ + +========================= +vhost-vDPA generic device +========================= + +This document explains the usage of the vhost-vDPA generic device. + + +Description +----------- + +vDPA(virtio data path acceleration) device is a device that uses a datapath +which complies with the virtio specifications with vendor specific control +path. + +QEMU provides two types of vhost-vDPA devices to enable the vDPA device, one +is type sensitive which means QEMU needs to know the actual device type +(e.g. net, blk, scsi) and another is called "vhost-vDPA generic device" which +is type insensitive. + +The vhost-vDPA generic device builds on the vhost-vdpa subsystem and virtio +subsystem. It is quite small, but it can support any type of virtio device. + + +Requirements +------------ +Linux 5.18+ +iproute2/vdpa 5.12.0+ + + +Examples +-------- + +1. Prepare the vhost-vDPA backends, here is an example using vdpa_sim_blk + device: + +:: + host# modprobe vhost_vdpa + host# modprobe vdpa_sim_blk + host# vdpa dev add mgmtdev vdpasim_blk name blk0 + (...you can see the vhost-vDPA device under /dev directory now...) + host# ls -l /dev/vhost-vdpa-* + crw------- 1 root root 236, 0 Nov 2 00:49 /dev/vhost-vdpa-0 + +Note: +It needs some vendor-specific steps to provision the vDPA device if you're +using real HW devices, such as loading the vendor-specific vDPA driver and +binding the device to the driver. + + +2. Start the virtual machine: + +Start QEMU with virtio-mmio bus: + +:: + host# qemu-system \ + -M microvm -m 512 -smp 2 -kernel ... -initrd ... \ + -device vhost-vdpa-device,vhostdev=/dev/vhost-vdpa-0 \ + ... + + +Start QEMU with virtio-pci bus: + +:: + host# qemu-system \ + -M pc -m 512 -smp 2 \ + -device vhost-vdpa-device-pci,vhostdev=/dev/vhost-vdpa-0 \ + ...