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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 852F4C4332B for ; Thu, 19 Mar 2020 03:45:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5144D20722 for ; Thu, 19 Mar 2020 03:45:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hni2Wwby" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726956AbgCSDpB (ORCPT ); Wed, 18 Mar 2020 23:45:01 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:58133 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726596AbgCSDpB (ORCPT ); Wed, 18 Mar 2020 23:45:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584589500; 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=V3IrYsm1nDYmYCrl6yeOdU+LoL6XC7ZlPWuzmgcSbtk=; b=hni2Wwby6IeMed1xVcMP97rgJOee1yvTSyGyBmkroB4dJvQetl3VUc+ML02/Nxoxj2DXnv oU2786DAGvsP/deHWXsfiX86HlWJBy5k/7FnYU8khs5iy71G7bArIZ9Qc6h6ha/Bs/Zbhj rCVudX87R6BpBaTYoA4YL2z/TALG3O8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-190-qH_aF-JePOmZbJ3uP1bOBg-1; Wed, 18 Mar 2020 23:44:56 -0400 X-MC-Unique: qH_aF-JePOmZbJ3uP1bOBg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 05FE31857BE0; Thu, 19 Mar 2020 03:44:53 +0000 (UTC) Received: from w520.home (ovpn-112-162.phx2.redhat.com [10.3.112.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id BB33F6EF97; Thu, 19 Mar 2020 03:44:50 +0000 (UTC) Date: Wed, 18 Mar 2020 21:44:50 -0600 From: Alex Williamson To: Kirti Wankhede Cc: , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v14 Kernel 3/7] vfio iommu: Add ioctl definition for dirty pages tracking. Message-ID: <20200318214450.358ca543@w520.home> In-Reply-To: <1584560474-19946-4-git-send-email-kwankhede@nvidia.com> References: <1584560474-19946-1-git-send-email-kwankhede@nvidia.com> <1584560474-19946-4-git-send-email-kwankhede@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, 19 Mar 2020 01:11:10 +0530 Kirti Wankhede wrote: > IOMMU container maintains a list of all pages pinned by vfio_pin_pages API. > All pages pinned by vendor driver through this API should be considered as > dirty during migration. When container consists of IOMMU capable device and > all pages are pinned and mapped, then all pages are marked dirty. > Added support to start/stop pinned and unpinned pages tracking and to get > bitmap of all dirtied pages for requested IO virtual address range. > > Signed-off-by: Kirti Wankhede > Reviewed-by: Neo Jia > --- > include/uapi/linux/vfio.h | 55 +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index d0021467af53..043e9eafb255 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -995,6 +995,12 @@ struct vfio_iommu_type1_dma_map { > > #define VFIO_IOMMU_MAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 13) > > +struct vfio_bitmap { > + __u64 pgsize; /* page size for bitmap */ > + __u64 size; /* in bytes */ > + __u64 __user *data; /* one bit per page */ > +}; > + > /** > * VFIO_IOMMU_UNMAP_DMA - _IOWR(VFIO_TYPE, VFIO_BASE + 14, > * struct vfio_dma_unmap) > @@ -1021,6 +1027,55 @@ struct vfio_iommu_type1_dma_unmap { > #define VFIO_IOMMU_ENABLE _IO(VFIO_TYPE, VFIO_BASE + 15) > #define VFIO_IOMMU_DISABLE _IO(VFIO_TYPE, VFIO_BASE + 16) > > +/** > + * VFIO_IOMMU_DIRTY_PAGES - _IOWR(VFIO_TYPE, VFIO_BASE + 17, > + * struct vfio_iommu_type1_dirty_bitmap) > + * IOCTL is used for dirty pages tracking. Caller sets argsz, which is size of > + * struct vfio_iommu_type1_dirty_bitmap. Caller set flag depend on which > + * operation to perform, details as below: > + * > + * When IOCTL is called with VFIO_IOMMU_DIRTY_PAGES_FLAG_START set, indicates > + * migration is active and IOMMU module should track pages which are pinned and > + * could be dirtied by device. "...should track" pages dirtied or potentially dirtied by devices. As soon as we add support for Yan's DMA r/w the pinning requirement is gone, besides pinning is an in-kernel implementation detail, the user of this interface doesn't know or care which pages are pinned. > + * Dirty pages are tracked until tracking is stopped by user application by > + * setting VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP flag. > + * > + * When IOCTL is called with VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP set, indicates > + * IOMMU should stop tracking pinned pages. s/pinned/dirtied/ > + * > + * When IOCTL is called with VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP flag set, > + * IOCTL returns dirty pages bitmap for IOMMU container during migration for > + * given IOVA range. User must provide data[] as the structure > + * vfio_iommu_type1_dirty_bitmap_get through which user provides IOVA range and > + * pgsize. This interface supports to get bitmap of smallest supported pgsize > + * only and can be modified in future to get bitmap of specified pgsize. > + * User must allocate memory for bitmap, zero the bitmap memory and set size > + * of allocated memory in bitmap_size field. One bit is used to represent one > + * page consecutively starting from iova offset. User should provide page size > + * in 'pgsize'. Bit set in bitmap indicates page at that offset from iova is > + * dirty. Caller must set argsz including size of structure > + * vfio_iommu_type1_dirty_bitmap_get. > + * > + * Only one flag should be set at a time. "Only one of the flags _START, _STOP, and _GET maybe be specified at a time." IOW, let's not presume what yet undefined flags may do. Hopefully this addresses Dave's concern. > + * > + */ > +struct vfio_iommu_type1_dirty_bitmap { > + __u32 argsz; > + __u32 flags; > +#define VFIO_IOMMU_DIRTY_PAGES_FLAG_START (1 << 0) > +#define VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP (1 << 1) > +#define VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP (1 << 2) > + __u8 data[]; > +}; > + > +struct vfio_iommu_type1_dirty_bitmap_get { > + __u64 iova; /* IO virtual address */ > + __u64 size; /* Size of iova range */ > + struct vfio_bitmap bitmap; > +}; > + > +#define VFIO_IOMMU_DIRTY_PAGES _IO(VFIO_TYPE, VFIO_BASE + 17) > + > /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ > > /*