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 X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31035C433E0 for ; Thu, 28 May 2020 21:05:26 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E01AE207BC for ; Thu, 28 May 2020 21:05:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="jO2TYWB6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E01AE207BC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51930 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jePiO-0006oR-Px for qemu-devel@archiver.kernel.org; Thu, 28 May 2020 17:05:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60914) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jePh1-0005sT-3Y for qemu-devel@nongnu.org; Thu, 28 May 2020 17:03:59 -0400 Received: from hqnvemgate24.nvidia.com ([216.228.121.143]:8810) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jePgz-0005wl-2k for qemu-devel@nongnu.org; Thu, 28 May 2020 17:03:58 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate24.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Thu, 28 May 2020 14:02:19 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Thu, 28 May 2020 14:03:50 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Thu, 28 May 2020 14:03:50 -0700 Received: from [10.40.100.117] (172.20.13.39) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 28 May 2020 21:03:36 +0000 Subject: Re: [PATCH Kernel v23 0/8] Add UAPIs to support migration for VFIO devices To: Yan Zhao References: <1589998088-3250-1-git-send-email-kwankhede@nvidia.com> <20200528044752.GB1378@joy-OptiPlex-7040> X-Nvconfidentiality: public From: Kirti Wankhede Message-ID: Date: Fri, 29 May 2020 02:33:32 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200528044752.GB1378@joy-OptiPlex-7040> X-Originating-IP: [172.20.13.39] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1590699740; bh=fNB6JVlPpuBzZY6lmvceCp6XLAO5nfIE6OxQGJkW1Kk=; h=X-PGP-Universal:Subject:To:CC:References:X-Nvconfidentiality:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=jO2TYWB62oR5JzaVPacznEhrRxLfNgL9TfUUFe7sHXGQNy7O0qCPeru+uowPZyFD/ 4cVuYJbRONUaoetmAcrGR3hQZrbCY1igdgq6xZ8TWgC496FkTl+kqgKcLfAWJmpcTH WsPdoFtQsS/sAvZg026Dghx1ZKFNdKBDnSDeix6pylVFm8LRtz89wr4EnY0OCihn+k Ujvw1/V4KzVSiFuFDyaMepU8abbHdPSs29TnsvIe8LBl9FehutT+BzMn5RI3Vx1NLX y8oXHqj00xuXe+9yc2NXSCFQXohX9MUdLtf6BnqyAzAL9qum4yAC0IcepQco9KQxbi vEL3+PjUd9GgQ== Received-SPF: pass client-ip=216.228.121.143; envelope-from=kwankhede@nvidia.com; helo=hqnvemgate24.nvidia.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/28 17:03:51 X-ACL-Warn: Detected OS = Windows 7 or 8 [fuzzy] X-Spam_score_int: -70 X-Spam_score: -7.1 X-Spam_bar: ------- X-Spam_report: (-7.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Zhengxiao.zx@Alibaba-inc.com, kevin.tian@intel.com, yi.l.liu@intel.com, cjia@nvidia.com, kvm@vger.kernel.org, eskultet@redhat.com, ziye.yang@intel.com, qemu-devel@nongnu.org, cohuck@redhat.com, shuangtai.tst@alibaba-inc.com, dgilbert@redhat.com, zhi.a.wang@intel.com, mlevitsk@redhat.com, pasic@linux.ibm.com, aik@ozlabs.ru, alex.williamson@redhat.com, eauger@redhat.com, felipe@nutanix.com, jonathan.davies@nutanix.com, changpeng.liu@intel.com, Ken.Xue@amd.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 5/28/2020 10:17 AM, Yan Zhao wrote: > > The whole series works for us in general: > Reviewed-by: Yan Zhao Thanks. Kirti > > On Wed, May 20, 2020 at 11:38:00PM +0530, Kirti Wankhede wrote: >> Hi, >> >> This patch set adds: >> * IOCTL VFIO_IOMMU_DIRTY_PAGES to get dirty pages bitmap with >> respect to IOMMU container rather than per device. All pages pinned by >> vendor driver through vfio_pin_pages external API has to be marked as >> dirty during migration. When IOMMU capable device is present in the >> container and all pages are pinned and mapped, then all pages are marked >> dirty. >> When there are CPU writes, CPU dirty page tracking can identify dirtied >> pages, but any page pinned by vendor driver can also be written by >> device. As of now there is no device which has hardware support for >> dirty page tracking. So all pages which are pinned should be considered >> as dirty. >> This ioctl is also used to start/stop dirty pages tracking for pinned and >> unpinned pages while migration is active. >> >> * Updated IOCTL VFIO_IOMMU_UNMAP_DMA to get dirty pages bitmap before >> unmapping IO virtual address range. >> With vIOMMU, during pre-copy phase of migration, while CPUs are still >> running, IO virtual address unmap can happen while device still keeping >> reference of guest pfns. Those pages should be reported as dirty before >> unmap, so that VFIO user space application can copy content of those >> pages from source to destination. >> >> * Patch 8 detect if IOMMU capable device driver is smart to report pages >> to be marked dirty by pinning pages using vfio_pin_pages() API. >> >> >> Yet TODO: >> Since there is no device which has hardware support for system memmory >> dirty bitmap tracking, right now there is no other API from vendor driver >> to VFIO IOMMU module to report dirty pages. In future, when such hardware >> support will be implemented, an API will be required such that vendor >> driver could report dirty pages to VFIO module during migration phases. >> >> v22 -> v23 >> - Fixed issue reported by Yan >> https://lore.kernel.org/kvm/97977ede-3c5b-c5a5-7858-7eecd7dd531c@nvidia.com/ >> - Fixed nit picks suggested by Cornelia >> >> v21 -> v22 >> - Fixed issue raised by Alex : >> https://lore.kernel.org/kvm/20200515163307.72951dd2@w520.home/ >> >> v20 -> v21 >> - Added checkin for GET_BITMAP ioctl for vfio_dma boundaries. >> - Updated unmap ioctl function - as suggested by Alex. >> - Updated comments in DIRTY_TRACKING ioctl definition - as suggested by >> Cornelia. >> >> v19 -> v20 >> - Fixed ioctl to get dirty bitmap to get bitmap of multiple vfio_dmas >> - Fixed unmap ioctl to get dirty bitmap of multiple vfio_dmas. >> - Removed flag definition from migration capability. >> >> v18 -> v19 >> - Updated migration capability with supported page sizes bitmap for dirty >> page tracking and maximum bitmap size supported by kernel module. >> - Added patch to calculate and cache pgsize_bitmap when iommu->domain_list >> is updated. >> - Removed extra buffers added in previous version for bitmap manipulation >> and optimised the code. >> >> v17 -> v18 >> - Add migration capability to the capability chain for VFIO_IOMMU_GET_INFO >> ioctl >> - Updated UMAP_DMA ioctl to return bitmap of multiple vfio_dma >> >> v16 -> v17 >> - Fixed errors reported by kbuild test robot on i386 >> >> v15 -> v16 >> - Minor edits and nit picks (Auger Eric) >> - On copying bitmap to user, re-populated bitmap only for pinned pages, >> excluding unmapped pages and CPU dirtied pages. >> - Patches are on tag: next-20200318 and 1-3 patches from Yan's series >> https://lkml.org/lkml/2020/3/12/1255 >> >> v14 -> v15 >> - Minor edits and nit picks. >> - In the verification of user allocated bitmap memory, added check of >> maximum size. >> - Patches are on tag: next-20200318 and 1-3 patches from Yan's series >> https://lkml.org/lkml/2020/3/12/1255 >> >> v13 -> v14 >> - Added struct vfio_bitmap to kabi. updated structure >> vfio_iommu_type1_dirty_bitmap_get and vfio_iommu_type1_dma_unmap. >> - All small changes suggested by Alex. >> - Patches are on tag: next-20200318 and 1-3 patches from Yan's series >> https://lkml.org/lkml/2020/3/12/1255 >> >> v12 -> v13 >> - Changed bitmap allocation in vfio_iommu_type1 to per vfio_dma >> - Changed VFIO_IOMMU_DIRTY_PAGES ioctl behaviour to be per vfio_dma range. >> - Changed vfio_iommu_type1_dirty_bitmap structure to have separate data >> field. >> >> v11 -> v12 >> - Changed bitmap allocation in vfio_iommu_type1. >> - Remove atomicity of ref_count. >> - Updated comments for migration device state structure about error >> reporting. >> - Nit picks from v11 reviews >> >> v10 -> v11 >> - Fix pin pages API to free vpfn if it is marked as unpinned tracking page. >> - Added proposal to detect if IOMMU capable device calls external pin pages >> API to mark pages dirty. >> - Nit picks from v10 reviews >> >> v9 -> v10: >> - Updated existing VFIO_IOMMU_UNMAP_DMA ioctl to get dirty pages bitmap >> during unmap while migration is active >> - Added flag in VFIO_IOMMU_GET_INFO to indicate driver support dirty page >> tracking. >> - If iommu_mapped, mark all pages dirty. >> - Added unpinned pages tracking while migration is active. >> - Updated comments for migration device state structure with bit >> combination table and state transition details. >> >> v8 -> v9: >> - Split patch set in 2 sets, Kernel and QEMU. >> - Dirty pages bitmap is queried from IOMMU container rather than from >> vendor driver for per device. Added 2 ioctls to achieve this. >> >> v7 -> v8: >> - Updated comments for KABI >> - Added BAR address validation check during PCI device's config space load >> as suggested by Dr. David Alan Gilbert. >> - Changed vfio_migration_set_state() to set or clear device state flags. >> - Some nit fixes. >> >> v6 -> v7: >> - Fix build failures. >> >> v5 -> v6: >> - Fix build failure. >> >> v4 -> v5: >> - Added decriptive comment about the sequence of access of members of >> structure vfio_device_migration_info to be followed based on Alex's >> suggestion >> - Updated get dirty pages sequence. >> - As per Cornelia Huck's suggestion, added callbacks to VFIODeviceOps to >> get_object, save_config and load_config. >> - Fixed multiple nit picks. >> - Tested live migration with multiple vfio device assigned to a VM. >> >> v3 -> v4: >> - Added one more bit for _RESUMING flag to be set explicitly. >> - data_offset field is read-only for user space application. >> - data_size is read for every iteration before reading data from migration, >> that is removed assumption that data will be till end of migration >> region. >> - If vendor driver supports mappable sparsed region, map those region >> during setup state of save/load, similarly unmap those from cleanup >> routines. >> - Handles race condition that causes data corruption in migration region >> during save device state by adding mutex and serialiaing save_buffer and >> get_dirty_pages routines. >> - Skip called get_dirty_pages routine for mapped MMIO region of device. >> - Added trace events. >> - Split into multiple functional patches. >> >> v2 -> v3: >> - Removed enum of VFIO device states. Defined VFIO device state with 2 >> bits. >> - Re-structured vfio_device_migration_info to keep it minimal and defined >> action on read and write access on its members. >> >> v1 -> v2: >> - Defined MIGRATION region type and sub-type which should be used with >> region type capability. >> - Re-structured vfio_device_migration_info. This structure will be placed >> at 0th offset of migration region. >> - Replaced ioctl with read/write for trapped part of migration region. >> - Added both type of access support, trapped or mmapped, for data section >> of the region. >> - Moved PCI device functions to pci file. >> - Added iteration to get dirty page bitmap until bitmap for all requested >> pages are copied. >> >> Thanks, >> Kirti >> >> >> Kirti Wankhede (8): >> vfio: UAPI for migration interface for device state >> vfio iommu: Remove atomicity of ref_count of pinned pages >> vfio iommu: Cache pgsize_bitmap in struct vfio_iommu >> vfio iommu: Add ioctl definition for dirty pages tracking >> vfio iommu: Implementation of ioctl for dirty pages tracking >> vfio iommu: Update UNMAP_DMA ioctl to get dirty bitmap before unmap >> vfio iommu: Add migration capability to report supported features >> vfio: Selective dirty page tracking if IOMMU backed device pins pages >> >> drivers/vfio/vfio.c | 13 +- >> drivers/vfio/vfio_iommu_type1.c | 571 ++++++++++++++++++++++++++++++++++++---- >> include/linux/vfio.h | 4 +- >> include/uapi/linux/vfio.h | 318 ++++++++++++++++++++++ >> 4 files changed, 847 insertions(+), 59 deletions(-) >> >> -- >> 2.7.0 >>