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 A4211C433F5 for ; Thu, 26 May 2022 12:44:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347343AbiEZMoB (ORCPT ); Thu, 26 May 2022 08:44:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344706AbiEZMny (ORCPT ); Thu, 26 May 2022 08:43:54 -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 8905F6D970 for ; Thu, 26 May 2022 05:43:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653569032; 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=hVZ34liVW5jS6yomiCvu033kCaJOcsPJqRRhNkEoRM0=; b=Ks7VasKF5KCERJ3xhk6PILnqKe8Dlo0lhvS5HjGsQwoXkATqmYIbTKCGUYn4DFEsitHIpy WSJ9L7fFSHZMGdQH/cuRUlR43uPtUW2b3qaluvNtWcJS8uughq9ZnlAxt9mAypZ5GJNimU h68hjzyU/1zbdDWM4sM/z4oVI1screM= 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-399-Zu8-CG4INu-KrkxgKoMtbQ-1; Thu, 26 May 2022 08:43:46 -0400 X-MC-Unique: Zu8-CG4INu-KrkxgKoMtbQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 189F53C1902B; Thu, 26 May 2022 12:43:45 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.194.139]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5B8B440CF8EA; Thu, 26 May 2022 12:43:40 +0000 (UTC) From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= To: "Michael S. Tsirkin" , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Jason Wang , netdev@vger.kernel.org Cc: martinh@xilinx.com, Stefano Garzarella , martinpo@xilinx.com, lvivier@redhat.com, pabloc@xilinx.com, Parav Pandit , Eli Cohen , Dan Carpenter , Xie Yongji , Christophe JAILLET , Zhang Min , Wu Zongyong , lulu@redhat.com, Zhu Lingshan , Piotr.Uminski@intel.com, Si-Wei Liu , ecree.xilinx@gmail.com, gautam.dawar@amd.com, habetsm.xilinx@gmail.com, tanuj.kamde@amd.com, hanand@xilinx.com, dinang@xilinx.com, Longpeng Subject: [PATCH v4 0/4] Implement vdpasim stop operation Date: Thu, 26 May 2022 14:43:34 +0200 Message-Id: <20220526124338.36247-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 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 v4:=0D * Replace VHOST_STOP to VHOST_VDPA_STOP in vhost ioctl switch case too.=0D =0D v3:=0D * s/VHOST_STOP/VHOST_VDPA_STOP/=0D * Add documentation and requirements of the ioctl above its definition.=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 | 14 ++++++++++++=0D include/uapi/linux/vhost_types.h | 2 ++=0D 8 files changed, 83 insertions(+), 1 deletion(-)=0D =0D -- =0D 2.31.1=0D =0D