From nobody Thu Jan 1 22:04:38 2026 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 BE2DCCDB47E for ; Thu, 19 Oct 2023 01:13:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232402AbjJSBNW (ORCPT ); Wed, 18 Oct 2023 21:13:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232180AbjJSBNL (ORCPT ); Wed, 18 Oct 2023 21:13:11 -0400 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E76E413E for ; Wed, 18 Oct 2023 18:13:05 -0700 (PDT) Received: from pps.filterd (m0246627.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 39IIoxPl012584; Thu, 19 Oct 2023 01:13:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2023-03-30; bh=uCLg4h3OhGVR2dAL7DV7TetiR50RwE+jQHhbu4th8Aw=; b=g31CCEf/47QmT9Nf8H9NE1tMPsXFw1u5UAsqVTZrZBKRHsZldozLeTWExRnrfk7zCKVU MMIGKwkDUROqZ9qZZtrzWXTk9ljqY1bM0JUsSHbjtsnFtOPHK1f1nBN1DvFV82r0yqb/ P/AaH4fdXgjpklxGMJ31m6RsacGH4+HSINkiBlEoQY+LAqPxOqQI2ZWXaBlojd0RIbL0 tNmZu3uiRhy8Ctry7GPQ4JJS64+MxqLznnyBZDSCkfLfNtH0K7I4jYerR9zjuNctZhTO o1OjCSWpCApxKdkhMQIre63oycs/A5r6DKWIrAFv8T/PlC6srI/aQyQg9CR/TrewOi+z cA== Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.appoci.oracle.com [130.35.103.27]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3tqk3js5a1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 19 Oct 2023 01:13:00 +0000 Received: from pps.filterd (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 39J0UpS3015251; Thu, 19 Oct 2023 01:12:59 GMT Received: from ban25x6uut24.us.oracle.com (ban25x6uut24.us.oracle.com [10.153.73.24]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 3trg1h8w2d-5; Thu, 19 Oct 2023 01:12:59 +0000 From: Si-Wei Liu To: jasowang@redhat.com, mst@redhat.com, eperezma@redhat.com, sgarzare@redhat.com, dtatulea@nvidia.com Cc: virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 4/5] vdpa/mlx5: implement .reset_map driver op Date: Wed, 18 Oct 2023 18:10:17 -0700 Message-Id: <1697677818-11371-5-git-send-email-si-wei.liu@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1697677818-11371-1-git-send-email-si-wei.liu@oracle.com> References: <1697677818-11371-1-git-send-email-si-wei.liu@oracle.com> X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-19_01,2023-10-18_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 phishscore=0 suspectscore=0 mlxscore=0 mlxlogscore=999 bulkscore=0 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310190007 X-Proofpoint-GUID: rMP4d_YVdx43I2M_oAzCMnb7X2CLmUNC X-Proofpoint-ORIG-GUID: rMP4d_YVdx43I2M_oAzCMnb7X2CLmUNC Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Since commit 6f5312f80183 ("vdpa/mlx5: Add support for running with virtio_vdpa"), mlx5_vdpa starts with preallocate 1:1 DMA MR at device creation time. This 1:1 DMA MR will be implicitly destroyed while the first .set_map call is invoked, in which case callers like vhost-vdpa will start to set up custom mappings. When the .reset callback is invoked, the custom mappings will be cleared and the 1:1 DMA MR will be re-created. In order to reduce excessive memory mapping cost in live migration, it is desirable to decouple the vhost-vdpa IOTLB abstraction from the virtio device life cycle, i.e. mappings can be kept around intact across virtio device reset. Leverage the .reset_map callback, which is meant to destroy the regular MR (including cvq mapping) on the given ASID and recreate the initial DMA mapping. That way, the device .reset op runs free from having to maintain and clean up memory mappings by itself. Add a module paramemter, persist_mapping, to cater for older userspace which may wish to see mapping to be cleared during reset. Co-developed-by: Dragos Tatulea Signed-off-by: Dragos Tatulea Signed-off-by: Si-Wei Liu --- drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 + drivers/vdpa/mlx5/core/mr.c | 17 +++++++++++++++++ drivers/vdpa/mlx5/net/mlx5_vnet.c | 26 ++++++++++++++++++++++++-- 3 files changed, 42 insertions(+), 2 deletions(-) diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/ml= x5_vdpa.h index db988ced5a5d..84547d998bcf 100644 --- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h +++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h @@ -127,6 +127,7 @@ int mlx5_vdpa_update_cvq_iotlb(struct mlx5_vdpa_dev *mv= dev, struct vhost_iotlb *iotlb, unsigned int asid); int mlx5_vdpa_create_dma_mr(struct mlx5_vdpa_dev *mvdev); +int mlx5_vdpa_reset_mr(struct mlx5_vdpa_dev *mvdev, unsigned int asid); =20 #define mlx5_vdpa_warn(__dev, format, ...) = \ dev_warn((__dev)->mdev->device, "%s:%d:(pid %d) warning: " format, __func= __, __LINE__, \ diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c index 66530e28f327..2197c46e563a 100644 --- a/drivers/vdpa/mlx5/core/mr.c +++ b/drivers/vdpa/mlx5/core/mr.c @@ -645,3 +645,20 @@ int mlx5_vdpa_create_dma_mr(struct mlx5_vdpa_dev *mvde= v) =20 return mlx5_vdpa_update_cvq_iotlb(mvdev, NULL, 0); } + +int mlx5_vdpa_reset_mr(struct mlx5_vdpa_dev *mvdev, unsigned int asid) +{ + if (asid >=3D MLX5_VDPA_NUM_AS) + return -EINVAL; + + mlx5_vdpa_destroy_mr(mvdev, mvdev->mr[asid]); + + if (asid =3D=3D 0 && MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) { + if (mlx5_vdpa_create_dma_mr(mvdev)) + mlx5_vdpa_warn(mvdev, "create DMA MR failed\n"); + } else { + mlx5_vdpa_update_cvq_iotlb(mvdev, NULL, asid); + } + + return 0; +} diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5= _vnet.c index f4516a2d5bb0..e809ccec6048 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -25,6 +25,11 @@ MODULE_AUTHOR("Eli Cohen "); MODULE_DESCRIPTION("Mellanox VDPA driver"); MODULE_LICENSE("Dual BSD/GPL"); =20 +static bool persist_mapping =3D true; +module_param(persist_mapping, bool, 0444); +MODULE_PARM_DESC(persist_mapping, + "Enable/disable persistent mapping across reset: 1 to keep, 0 to clear"= ); + #define VALID_FEATURES_MASK = \ (BIT_ULL(VIRTIO_NET_F_CSUM) | BIT_ULL(VIRTIO_NET_F_GUEST_CSUM) | = \ BIT_ULL(VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) | BIT_ULL(VIRTIO_NET_F_MTU) | = BIT_ULL(VIRTIO_NET_F_MAC) | \ @@ -2888,7 +2893,8 @@ static int mlx5_vdpa_reset(struct vdpa_device *vdev) unregister_link_notifier(ndev); teardown_driver(ndev); clear_vqs_ready(ndev); - mlx5_vdpa_destroy_mr_resources(&ndev->mvdev); + if (unlikely(!persist_mapping)) + mlx5_vdpa_destroy_mr_resources(&ndev->mvdev); ndev->mvdev.status =3D 0; ndev->mvdev.suspended =3D false; ndev->cur_num_vqs =3D 0; @@ -2899,7 +2905,7 @@ static int mlx5_vdpa_reset(struct vdpa_device *vdev) init_group_to_asid_map(mvdev); ++mvdev->generation; =20 - if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) { + if (unlikely(!persist_mapping) && MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) { if (mlx5_vdpa_create_dma_mr(mvdev)) mlx5_vdpa_warn(mvdev, "create MR failed\n"); } @@ -2987,6 +2993,18 @@ static int mlx5_vdpa_set_map(struct vdpa_device *vde= v, unsigned int asid, return err; } =20 +static int mlx5_vdpa_reset_map(struct vdpa_device *vdev, unsigned int asid) +{ + struct mlx5_vdpa_dev *mvdev =3D to_mvdev(vdev); + struct mlx5_vdpa_net *ndev =3D to_mlx5_vdpa_ndev(mvdev); + int err; + + down_write(&ndev->reslock); + err =3D mlx5_vdpa_reset_mr(mvdev, asid); + up_write(&ndev->reslock); + return err; +} + static struct device *mlx5_get_vq_dma_dev(struct vdpa_device *vdev, u16 id= x) { struct mlx5_vdpa_dev *mvdev =3D to_mvdev(vdev); @@ -3255,6 +3273,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops =3D= { .set_config =3D mlx5_vdpa_set_config, .get_generation =3D mlx5_vdpa_get_generation, .set_map =3D mlx5_vdpa_set_map, + .reset_map =3D mlx5_vdpa_reset_map, /* Op disabled on !persist_mapping */ .set_group_asid =3D mlx5_set_group_asid, .get_vq_dma_dev =3D mlx5_get_vq_dma_dev, .free =3D mlx5_vdpa_free, @@ -3630,6 +3649,9 @@ static int mlx5v_probe(struct auxiliary_device *adev, if (!MLX5_CAP_DEV_VDPA_EMULATION(mdev, desc_group_mkey_supported)) mgtdev->vdpa_ops.get_vq_desc_group =3D NULL; =20 + if (unlikely(!persist_mapping)) + mgtdev->vdpa_ops.reset_map =3D NULL; + err =3D vdpa_mgmtdev_register(&mgtdev->mgtdev); if (err) goto reg_err; --=20 2.39.3