From patchwork Thu Jun 23 16:07:34 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 12892878 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 AAFB0C43334 for ; Thu, 23 Jun 2022 16:07:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232143AbiFWQH4 (ORCPT ); Thu, 23 Jun 2022 12:07:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232135AbiFWQHy (ORCPT ); Thu, 23 Jun 2022 12:07:54 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 43F9B4505F for ; Thu, 23 Jun 2022 09:07:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656000470; 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=S3oCRCXEV1K9DsN6PfqUynkZmDYWF6Rf7y0C3Au1By4=; b=bllGs+0aesPb2VvzOMzYV1+kNiIvSPuyGuTSsV3v3VZKD1Sln9N1fQBT/OwIhkY+AvSWWj zKMyNHK2nHIQLVDx1KXp6vdidFuU+V9SxRVycVYl22uWXVB2eRokrJPWV+i+l9mVL7EP3x dDEeZDzwRdLTyrmQm95mVqZywi/LxPQ= 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-62-3LdcDvSdOlKw1ZaLMZpg2Q-1; Thu, 23 Jun 2022 12:07:46 -0400 X-MC-Unique: 3LdcDvSdOlKw1ZaLMZpg2Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5F6071C04B42; Thu, 23 Jun 2022 16:07:45 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.194.38]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACA7C2166B26; Thu, 23 Jun 2022 16:07:40 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: netdev@vger.kernel.org, Jason Wang , linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, "Michael S. Tsirkin" Cc: Parav Pandit , Christophe JAILLET , lulu@redhat.com, tanuj.kamde@amd.com, Si-Wei Liu , Piotr.Uminski@intel.com, habetsm.xilinx@gmail.com, gautam.dawar@amd.com, pabloc@xilinx.com, Zhu Lingshan , lvivier@redhat.com, Longpeng , dinang@xilinx.com, martinh@xilinx.com, martinpo@xilinx.com, Eli Cohen , ecree.xilinx@gmail.com, Wu Zongyong , Stefano Garzarella , Dan Carpenter , hanand@xilinx.com, Xie Yongji , Zhang Min Subject: [PATCH v6 0/4] Implement vdpasim suspend operation Date: Thu, 23 Jun 2022 18:07:34 +0200 Message-Id: <20220623160738.632852-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Implement suspend operation for vdpa_sim devices, so vhost-vdpa will offer that backend feature and userspace can effectively suspend the device. This is a must before getting virtqueue indexes (base) for live migration, since the device could modify them after userland gets them. There are individual ways to perform that action for some devices (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no way to perform it for any vhost device (and, in particular, vhost-vdpa). After a successful return of ioctl the device must not process more virtqueue descriptors. The device can answer to read or writes of config fields as if it were not suspended. In particular, writing to "queue_enable" with a value of 1 will not make the device start processing virtqueue buffers. In the future, we will provide features similar to VHOST_USER_GET_INFLIGHT_FD so the device can save pending operations. Comments are welcome. v7: * Remove the resume operation, making the ioctl simpler. We can always add another ioctl for VM_STOP/VM_RESUME operation later. v6: * s/stop/suspend/ to differentiate more from reset. * Clarify scope of the suspend operation. v5: * s/not stop/resume/ in doc. v4: * Replace VHOST_STOP to VHOST_VDPA_STOP in vhost ioctl switch case too. v3: * s/VHOST_STOP/VHOST_VDPA_STOP/ * Add documentation and requirements of the ioctl above its definition. v2: * Replace raw _F_STOP with BIT_ULL(_F_STOP). * Fix obtaining of stop ioctl arg (it was not obtained but written). * Add stop to vdpa_sim_blk. Eugenio Pérez (4): vdpa: Add suspend operation vhost-vdpa: introduce SUSPEND backend feature bit vhost-vdpa: uAPI to suspend the device vdpa_sim: Implement suspend vdpa op drivers/vdpa/vdpa_sim/vdpa_sim.c | 21 +++++++++++++++++ drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 + drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++ drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++ drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++++++- include/linux/vdpa.h | 4 ++++ include/uapi/linux/vhost.h | 14 +++++++++++ include/uapi/linux/vhost_types.h | 2 ++ 8 files changed, 82 insertions(+), 1 deletion(-)