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 41BDEC433FE for ; Tue, 24 May 2022 17:07:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239858AbiEXRG6 (ORCPT ); Tue, 24 May 2022 13:06:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239883AbiEXRGy (ORCPT ); Tue, 24 May 2022 13:06:54 -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 A2E8A8199B for ; Tue, 24 May 2022 10:06:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653412006; 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: in-reply-to:in-reply-to:references:references; bh=NRVyuXQ2anZsMTN0V2Kp61WOvAM/LWYlpRTqMTKf390=; b=iOg2BOjLLNPpZOFMYo7dFoUNRnTOsun9EvJ7OyFhBc5rr+1lDPvUl/tdw7U9A/XInJzS5Q bh1PjnIQa1NNKopJUyjDrbAHS/RlYGNBIbKg3z41+EzY0YEtDi//faksPsf/lnnP/rg/PP 9RQM6LimSKWCZHPiDLMDZKG0zPW9WfY= 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-590-hHqKpHFUOOKaGi6FSPlasQ-1; Tue, 24 May 2022 13:06:42 -0400 X-MC-Unique: hHqKpHFUOOKaGi6FSPlasQ-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 7F5121C08973; Tue, 24 May 2022 17:06:36 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.195.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 12CC92026D64; Tue, 24 May 2022 17:06:31 +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 4/4] vdpa_sim: Implement stop vdpa op Date: Tue, 24 May 2022 19:06:10 +0200 Message-Id: <20220524170610.2255608-5-eperezma@redhat.com> In-Reply-To: <20220524170610.2255608-1-eperezma@redhat.com> References: <20220524170610.2255608-1-eperezma@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 that backend feature and userspace can effectively stop the device. This is a must before get 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 the return of ioctl with stop != 0, the device MUST finish any pending operations like in flight requests. It must also preserve all the necessary state (the virtqueue vring base plus the possible device specific states) that is required for restoring in the future. The device must not change its configuration after that point. After the return of ioctl with stop == 0, the device can continue processing buffers as long as typical conditions are met (vq is enabled, DRIVER_OK status bit is enabled, etc). In the future, we will provide features similar to VHOST_USER_GET_INFLIGHT_FD so the device can save pending operations. Signed-off-by: Eugenio Pérez --- 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 +++ 4 files changed, 28 insertions(+) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c index 50d721072beb..0515cf314bed 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -107,6 +107,7 @@ static void vdpasim_do_reset(struct vdpasim *vdpasim) for (i = 0; i < vdpasim->dev_attr.nas; i++) vhost_iotlb_reset(&vdpasim->iommu[i]); + vdpasim->running = true; spin_unlock(&vdpasim->iommu_lock); vdpasim->features = 0; @@ -505,6 +506,24 @@ static int vdpasim_reset(struct vdpa_device *vdpa) return 0; } +static int vdpasim_stop(struct vdpa_device *vdpa, bool stop) +{ + struct vdpasim *vdpasim = vdpa_to_sim(vdpa); + int i; + + spin_lock(&vdpasim->lock); + vdpasim->running = !stop; + if (vdpasim->running) { + /* Check for missed buffers */ + for (i = 0; i < vdpasim->dev_attr.nvqs; ++i) + vdpasim_kick_vq(vdpa, i); + + } + spin_unlock(&vdpasim->lock); + + return 0; +} + static size_t vdpasim_get_config_size(struct vdpa_device *vdpa) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); @@ -694,6 +713,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = { .get_status = vdpasim_get_status, .set_status = vdpasim_set_status, .reset = vdpasim_reset, + .stop = vdpasim_stop, .get_config_size = vdpasim_get_config_size, .get_config = vdpasim_get_config, .set_config = vdpasim_set_config, @@ -726,6 +746,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = { .get_status = vdpasim_get_status, .set_status = vdpasim_set_status, .reset = vdpasim_reset, + .stop = vdpasim_stop, .get_config_size = vdpasim_get_config_size, .get_config = vdpasim_get_config, .set_config = vdpasim_set_config, diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h index 622782e92239..061986f30911 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h @@ -66,6 +66,7 @@ struct vdpasim { u32 generation; u64 features; u32 groups; + bool running; /* spinlock to synchronize iommu table */ spinlock_t iommu_lock; }; diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c index 42d401d43911..bcdb1982c378 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -204,6 +204,9 @@ static void vdpasim_blk_work(struct work_struct *work) if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) goto out; + if (!vdpasim->running) + goto out; + for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) { struct vdpasim_virtqueue *vq = &vdpasim->vqs[i]; diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c index 5125976a4df8..886449e88502 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c @@ -154,6 +154,9 @@ static void vdpasim_net_work(struct work_struct *work) spin_lock(&vdpasim->lock); + if (!vdpasim->running) + goto out; + if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) goto out; -- 2.27.0