TESTING: vfio: Add support for Shared Virtual Addressing

maillist inclusion
category: feature
bugzilla: 51855
CVE: NA

Reference: https://jpbrucker.net/git/linux/commit/?h=sva/2021-03-01&id=836544e7c81361379e509eeca568d64f8f3dfbe2



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Add two new ioctls for VFIO containers. VFIO_IOMMU_BIND_PROCESS creates a
bond between a container and a process address space, identified by a
Process Address Space ID (PASID). Devices in the container append this
PASID to DMA transactions in order to access the process' address space.
The process page tables are shared with the IOMMU, and mechanisms such as
PCI ATS/PRI are used to handle faults. VFIO_IOMMU_UNBIND_PROCESS removes a
bond created with VFIO_IOMMU_BIND_PROCESS.

This patch is only provided for testing. It isn't possible to implement
SVA with vfio-pci, because the generic VFIO driver doesn't know how to
perform device-specific methods for stopping the use of PASID. This
could be achieved with vfio-mdev and a mediating driver that knows how
to perform stop PASID.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Lijun Fang <fanglijun3@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>