From patchwork Tue May 24 17:06:08 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: 12860378 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 BF237C433F5 for ; Tue, 24 May 2022 17:06:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239852AbiEXRGm (ORCPT ); Tue, 24 May 2022 13:06:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239844AbiEXRGg (ORCPT ); Tue, 24 May 2022 13:06:36 -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 CF9BD7E1EC for ; Tue, 24 May 2022 10:06:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653411993; 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=iHJ6PFjviDqPYy85yFDxjKt/WK/68mxqW6ae6Xic7iM=; b=VEdcC4zNghKVe5NrRJllLsq45Pt1eOBL8uN1M7+EbK46iDQ47e6x+G+AL8QMnCRpA/MjT7 X+aC0OggGk1ThOVh/YM67hUbtqfQuGYQ3jUyOgdXlwSBUCtFZNtG5eNHF1kV1E6/MvLehX QDDeyIyngO68rDHyLaMb3Yh9sdXES0s= 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-595-4c-QiSYPMp6N3M1c3Boy5g-1; Tue, 24 May 2022 13:06:28 -0400 X-MC-Unique: 4c-QiSYPMp6N3M1c3Boy5g-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 18366299E776; Tue, 24 May 2022 17:06:27 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.195.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9204A2026D64; Tue, 24 May 2022 17:06:22 +0000 (UTC) From: =?utf-8?q?Eugenio_P=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 2/4] vhost-vdpa: introduce STOP backend feature bit Date: Tue, 24 May 2022 19:06:08 +0200 Message-Id: <20220524170610.2255608-3-eperezma@redhat.com> In-Reply-To: <20220524170610.2255608-1-eperezma@redhat.com> References: <20220524170610.2255608-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Userland knows if it can stop the device or not by checking this feature bit. It's only offered if the vdpa driver backend implements the stop() operation callback, and try to set it if the backend does not offer that callback is an error. Signed-off-by: Eugenio Pérez --- drivers/vhost/vdpa.c | 16 +++++++++++++++- include/uapi/linux/vhost_types.h | 2 ++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 1f1d1c425573..32713db5831d 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -347,6 +347,14 @@ static long vhost_vdpa_set_config(struct vhost_vdpa *v, return 0; } +static bool vhost_vdpa_can_stop(const struct vhost_vdpa *v) +{ + struct vdpa_device *vdpa = v->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + + return ops->stop; +} + static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep) { struct vdpa_device *vdpa = v->vdpa; @@ -575,7 +583,11 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, if (cmd == VHOST_SET_BACKEND_FEATURES) { if (copy_from_user(&features, featurep, sizeof(features))) return -EFAULT; - if (features & ~VHOST_VDPA_BACKEND_FEATURES) + if (features & ~(VHOST_VDPA_BACKEND_FEATURES | + BIT_ULL(VHOST_BACKEND_F_STOP))) + return -EOPNOTSUPP; + if ((features & BIT_ULL(VHOST_BACKEND_F_STOP)) && + !vhost_vdpa_can_stop(v)) return -EOPNOTSUPP; vhost_set_backend_features(&v->vdev, features); return 0; @@ -624,6 +636,8 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, break; case VHOST_GET_BACKEND_FEATURES: features = VHOST_VDPA_BACKEND_FEATURES; + if (vhost_vdpa_can_stop(v)) + features |= BIT_ULL(VHOST_BACKEND_F_STOP); if (copy_to_user(featurep, &features, sizeof(features))) r = -EFAULT; break; diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h index 634cee485abb..2758e665791b 100644 --- a/include/uapi/linux/vhost_types.h +++ b/include/uapi/linux/vhost_types.h @@ -161,5 +161,7 @@ struct vhost_vdpa_iova_range { * message */ #define VHOST_BACKEND_F_IOTLB_ASID 0x3 +/* Stop device from processing virtqueue buffers */ +#define VHOST_BACKEND_F_STOP 0x4 #endif