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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95EA4C433EF for ; Tue, 24 May 2022 17:07:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239892AbiEXRHj (ORCPT ); Tue, 24 May 2022 13:07:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237434AbiEXRHf (ORCPT ); Tue, 24 May 2022 13:07:35 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D5FC27E1DD for ; Tue, 24 May 2022 10:07:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653412053; 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=GxIUBanOlo4kCZlBLy+vq6QBMWA1M+KHEcRWloPp9vs=; b=RDzRrM0cu6ymwdPI02GANmAbjZByVyzbQN2+DJ+keBVgb23PyAPbpV2mnuo/JvSFl0EHuB 6E6c6K2YOM0FXk/AvzCGXANIeB2lUvVB6wsiiZ0NInu6VQEuYIl2y+1LDvFVrUZiyziH8w XCbpy7nLJInhUzPD2tC3qK+BybHAVQs= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-151-2xLvnYQCMHOtyYr0ccgPhw-1; Tue, 24 May 2022 13:06:18 -0400 X-MC-Unique: 2xLvnYQCMHOtyYr0ccgPhw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7F2692999B2D; Tue, 24 May 2022 17:06:17 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.195.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9EB7D2026D64; Tue, 24 May 2022 17:06:12 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, Jason Wang , "Michael S. Tsirkin" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Parav Pandit , Zhang Min , hanand@xilinx.com, Zhu Lingshan , tanuj.kamde@amd.com, gautam.dawar@amd.com, Christophe JAILLET , Xie Yongji , dinang@xilinx.com, habetsm.xilinx@gmail.com, Eli Cohen , pabloc@xilinx.com, lvivier@redhat.com, Dan Carpenter , lulu@redhat.com, Wu Zongyong , eperezma@redhat.com, ecree.xilinx@gmail.com, Piotr.Uminski@intel.com, martinpo@xilinx.com, Stefano Garzarella , Si-Wei Liu , Longpeng , martinh@xilinx.com Subject: [PATCH v2 0/4] Implement vdpasim stop operation Date: Tue, 24 May 2022 19:06:06 +0200 Message-Id: <20220524170610.2255608-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implement stop operation for vdpa_sim devices, so vhost-vdpa will offer=0D that backend feature and userspace can effectively stop the device.=0D =0D This is a must before get virtqueue indexes (base) for live migration,=0D since the device could modify them after userland gets them. There are=0D individual ways to perform that action for some devices=0D (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no=0D way to perform it for any vhost device (and, in particular, vhost-vdpa).=0D =0D After the return of ioctl with stop !=3D 0, the device MUST finish any=0D pending operations like in flight requests. It must also preserve all=0D the necessary state (the virtqueue vring base plus the possible device=0D specific states) that is required for restoring in the future. The=0D device must not change its configuration after that point.=0D =0D After the return of ioctl with stop =3D=3D 0, the device can continue=0D processing buffers as long as typical conditions are met (vq is enabled,=0D DRIVER_OK status bit is enabled, etc).=0D =0D In the future, we will provide features similar to VHOST_USER_GET_INFLIGHT_= FD=0D so the device can save pending operations.=0D =0D Comments are welcome.=0D =0D v2:=0D * Replace raw _F_STOP with BIT_ULL(_F_STOP).=0D * Fix obtaining of stop ioctl arg (it was not obtained but written).=0D * Add stop to vdpa_sim_blk.=0D =0D Eugenio P=C3=A9rez (4):=0D vdpa: Add stop operation=0D vhost-vdpa: introduce STOP backend feature bit=0D vhost-vdpa: uAPI to stop the device=0D vdpa_sim: Implement stop vdpa op=0D =0D drivers/vdpa/vdpa_sim/vdpa_sim.c | 21 +++++++++++++++++=0D drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +=0D drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++=0D drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++=0D drivers/vhost/vdpa.c | 34 +++++++++++++++++++++++++++-=0D include/linux/vdpa.h | 6 +++++=0D include/uapi/linux/vhost.h | 3 +++=0D include/uapi/linux/vhost_types.h | 2 ++=0D 8 files changed, 72 insertions(+), 1 deletion(-)=0D =0D -- =0D 2.27.0=0D =0D