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 C23FDC25B48 for ; Thu, 26 Oct 2023 07:17:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344207AbjJZHRe (ORCPT ); Thu, 26 Oct 2023 03:17:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229518AbjJZHRc (ORCPT ); Thu, 26 Oct 2023 03:17:32 -0400 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 633E7129 for ; Thu, 26 Oct 2023 00:17:30 -0700 (PDT) Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 39Q3TVX3026203; Thu, 26 Oct 2023 07:17:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-type : content-transfer-encoding; s=corp-2023-03-30; bh=X3a3iMFmYQw/CMdUXMYbinGUijqCuBut6pJA3oZ9q40=; b=dtiBETwYeqenKYB3667NRLSJibQtUKO2SmxLXMuzkC4GzWTS9iNMrShenwsaw+LWVsHL YhGJWG+Kx+DPW2yRhmpLoBCggkQsr7oC/Kuh36dRmhhK4YxL/cI9DgCDhSAfx0Yv1VAC 3fWHTMoy5O3sQezUTYgw6EEl+zzF+BnkYGzCPcNvummZEbB+Xxs8Nl2tsKXzgXYLC3Ao RiXToDrIvXkq79MPuWBLgMK/0Ic+IxBnpTNkiEvHo30DuwfJmJ9EPeieA5rqVLLvO/Kq FcRwzyP7rUPprxuXnvn2flA5TLl6dj61wek71Ad2iQ1FXNEV+sZ5FI5ZG+2DXltlnG/F Yw== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3tv52e2bvr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 26 Oct 2023 07:17:26 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 39Q6tbAE015200; Thu, 26 Oct 2023 07:17:25 GMT Received: from ban25x6uut24.us.oracle.com (ban25x6uut24.us.oracle.com [10.153.73.24]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3tv537t53r-1; Thu, 26 Oct 2023 07:17:24 +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 v5 0/7] vdpa: decouple reset of iotlb mapping from device reset Date: Thu, 26 Oct 2023 00:14:33 -0700 Message-Id: <1698304480-18463-1-git-send-email-si-wei.liu@oracle.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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=2023-10-26_04,2023-10-25_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxlogscore=999 bulkscore=0 mlxscore=0 spamscore=0 malwarescore=0 suspectscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2310170001 definitions=main-2310260060 X-Proofpoint-ORIG-GUID: qJzScXUnYZ5ovVfehxHlTl8PaF3d8GsY X-Proofpoint-GUID: qJzScXUnYZ5ovVfehxHlTl8PaF3d8GsY Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to reduce needlessly high setup and teardown cost of iotlb mapping during live migration, it's crucial to decouple the vhost-vdpa iotlb abstraction from the virtio device life cycle, i.e. iotlb mappings should be left intact across virtio device reset [1]. For it to work, the on-chip IOMMU parent device could implement a separate .reset_map() operation callback to restore 1:1 DMA mapping without having to resort to the .reset() callback, the latter of which is mainly used to reset virtio device state. This new .reset_map() callback will be invoked only before the vhost-vdpa driver is to be removed and detached from the vdpa bus, such that other vdpa bus drivers, e.g. virtio-vdpa, can start with 1:1 DMA mapping when they are attached. For the context, those on-chip IOMMU parent devices, create the 1:1 DMA mapping at vdpa device creation, and they would implicitly destroy the 1:1 mapping when the first .set_map or .dma_map callback is invoked. This patchset is rebased on top of the latest vhost tree. [1] Reducing vdpa migration downtime because of memory pin / maps https://www.mail-archive.com/qemu-devel@nongnu.org/msg953755.html --- v5: - Squashed two fixups to the clean map patch v4: - Rework compatibility using new .compat_reset driver op v3: - add .reset_map support to vdpa_sim - introduce module parameter to provide bug-for-bug compatibility with older userspace v2: - improved commit message to clarify the intended csope of .reset_map API - improved commit messages to clarify no breakage on older userspace v1: - rewrote commit messages to include more detailed description and background - reword to vendor specific IOMMU implementation from on-chip IOMMU - include parent device backend feautres to persistent iotlb precondition - reimplement mlx5_vdpa patch on top of descriptor group series RFC v3: - fix missing return due to merge error in patch #4 RFC v2: - rebased on top of the "[PATCH RFC v2 0/3] vdpa: dedicated descriptor table group" series: https://lore.kernel.org/virtualization/1694248959-13369-1-git-send-email-si-wei.liu@oracle.com/ --- Si-Wei Liu (7): vdpa: introduce .reset_map operation callback vhost-vdpa: reset vendor specific mapping to initial state in .release vhost-vdpa: introduce IOTLB_PERSIST backend feature bit vdpa: introduce .compat_reset operation callback vhost-vdpa: clean iotlb map during reset for older userspace vdpa/mlx5: implement .reset_map driver op vdpa_sim: implement .reset_map support drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 + drivers/vdpa/mlx5/core/mr.c | 17 ++++++++++ drivers/vdpa/mlx5/net/mlx5_vnet.c | 27 ++++++++++++++-- drivers/vdpa/vdpa_sim/vdpa_sim.c | 52 ++++++++++++++++++++++++------ drivers/vhost/vdpa.c | 52 +++++++++++++++++++++++++++--- drivers/virtio/virtio_vdpa.c | 2 +- include/linux/vdpa.h | 30 +++++++++++++++-- include/uapi/linux/vhost_types.h | 2 ++ 8 files changed, 164 insertions(+), 19 deletions(-) -- 2.39.3