Re: [Qemu-devel] [RFC 0/8] VIRTIO-IOMMU device

[Jason Wang]

On 2017年06月07日 16:35, Eric Auger wrote:
> This series implements the virtio-iommu device. This is a proof
> of concept based on the virtio-iommu specification written by
> Jean-Philippe Brucker [1]. This was tested with a guest using
> the virtio-iommu driver [2] and exposed with a virtio-net-pci
> using dma ops.
>
> The device gets instantiated using the "-device virtio-iommu-device"
> option. It currently works with ARM virt machine only as the machine
> must handle the dt binding between the virtio-mmio "iommu" node and
> the PCI host bridge node. ACPI booting is not yet supported.
>
> This should allow to start some benchmarking activities against
> pure emulated IOMMU (especially ARM SMMU).

Yes, it would be also interesting to compare it with intel IOMMU. 
Actually the core function is similar to the subset of intel one with CM 
enabled. Since each map and unmap requires a command, it would be very 
slow for dynamic mappings. I wonder whether or not we can do any 
optimization on this.

Thanks

> Best Regards
>
> Eric
>
> This series can be found at:
> https://github.com/eauger/qemu/tree/virtio-iommu-rfcv1
>
> References:
> [1] [RFC 0/3] virtio-iommu: a paravirtualized IOMMU,
> [2] [RFC PATCH linux] iommu: Add virtio-iommu driver
> [3] [RFC PATCH kvmtool 00/15] Add virtio-iommu
>
> Eric Auger (8):
>    update-linux-headers: import virtio_iommu.h
>    linux-headers: Update for virtio-iommu
>    virtio_iommu: add skeleton
>    virtio-iommu: Decode the command payload
>    virtio_iommu: Add the iommu regions
>    virtio-iommu: Implement the translation and commands
>    hw/arm/virt: Add 2.10 machine type
>    hw/arm/virt: Add virtio-iommu the virt board
>
>   hw/arm/virt.c                                 | 116 ++++-
>   hw/virtio/Makefile.objs                       |   1 +
>   hw/virtio/trace-events                        |  14 +
>   hw/virtio/virtio-iommu.c                      | 623 ++++++++++++++++++++++++++
>   include/hw/arm/virt.h                         |   5 +
>   include/hw/virtio/virtio-iommu.h              |  60 +++
>   include/standard-headers/linux/virtio_ids.h   |   1 +
>   include/standard-headers/linux/virtio_iommu.h | 142 ++++++
>   linux-headers/linux/virtio_iommu.h            |   1 +
>   scripts/update-linux-headers.sh               |   3 +
>   10 files changed, 957 insertions(+), 9 deletions(-)
>   create mode 100644 hw/virtio/virtio-iommu.c
>   create mode 100644 include/hw/virtio/virtio-iommu.h
>   create mode 100644 include/standard-headers/linux/virtio_iommu.h
>   create mode 100644 linux-headers/linux/virtio_iommu.h