[PATCH v2 0/4] Have TTM support SEV encryption with coherent memory

[Thomas Hellström (VMware)]

With SEV memory encryption and in some cases also with SME memory
encryption, coherent memory is unencrypted. In those cases, TTM doesn't
set up the correct page protection. Fix this by having the TTM
coherent page allocator call into the platform code to determine whether
coherent memory is encrypted or not, and modify the page protection if
it is not.

v2:
- Use force_dma_unencrypted() rather than sev_active() to catch also the
  special SME encryption cases.