iommu: introduce iommu invalidate API function

hulk inclusion
category: feature
bugzilla: 14369
CVE: NA
-------------------

When an SVM capable device is assigned to a guest, the first level page
tables are owned by the guest and the guest PASID table pointer is
linked to the device context entry of the physical IOMMU.

Host IOMMU driver has no knowledge of caching structure updates unless
the guest invalidation activities are passed down to the host. The
primary usage is derived from emulated IOMMU in the guest, where QEMU
can trap invalidation activities before passing them down to the
host/physical IOMMU.
Since the invalidation data are obtained from user space and will be
written into physical IOMMU, we must allow security check at various
layers. Therefore, generic invalidation data format are proposed here,
model specific IOMMU drivers need to convert them into their own format.

Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Fang Lijun <fanglijun3@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>