Re: [RFC PATCH 0/3] vfio/migration: Support manual clear vfio dirty log

[Kunkun Jiang <jiangkunkun@huawei.com>]

Hi all,

Sorry for my carelessness.
This is the v2 of this series.

Thanks,
Kunkun Jiang

On 2021/5/8 17:31, Kunkun Jiang wrote:
> In the past, we clear dirty log immediately after sync dirty log to
> userspace. This may cause redundant dirty handling if userspace
> handles dirty log iteratively:
>
> After vfio clears dirty log, new dirty log starts to generate. These
> new dirty log will be reported to userspace even if they are generated
> before userspace handles the same dirty page.
>
> Since a new dirty log tracking method for vfio based on iommu hwdbm[1]
> has been introduced in the kernel and added a new capability named
> VFIO_DIRTY_LOG_MANUAL_CLEAR, we can eliminate some redundant dirty
> handling by supporting it.
>
> This series include patches as below:
> Patch 1:
> - updated the linux-headers/linux/vfio.h from kernel side
>
> Patch 2:
> - introduced 'struct VFIODMARange' to describe a range of the given DMA
>    mapping and with respect to a VFIO_IOMMU_MAP_DMA operation
>
> Patch 3:
> - implemented the operation to manual clear vfio dirty log, which can
>    eliminate some redundant dirty handling
>
> History:
> v1 -> v2:
> - Add a new ioctl VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP_NOCLEAR to get
>    vfio dirty log when support manual clear.
>
> Thanks,
> Kunkun Jiang
>
> [1]
> IOMMU part: https://lore.kernel.org/linux-iommu/20210507102211.8836-1-zhukeqian1@huawei.com/
> VFIO part: https://lore.kernel.org/kvm/20210507103608.39440-1-zhukeqian1@huawei.com/
>
> Zenghui Yu (3):
>    linux-headers: update against 5.12 and "manual clear vfio dirty log"
>      series
>    vfio: Maintain DMA mapping range for the container
>    vfio/migration: Add support for manual clear vfio dirty log
>
>   hw/vfio/common.c              | 211 ++++++++++++++++++++++++++++++++--
>   include/hw/vfio/vfio-common.h |  10 ++
>   linux-headers/linux/vfio.h    |  61 +++++++++-
>   3 files changed, 273 insertions(+), 9 deletions(-)
>