KVM: arm64: Add pkvm_hyp_req infrastructure

Introduce a struct pkvm_hyp_req to enable the pKVM hypervisor to request
resources from the host.

Provide serialisation helpers to transport these requests via SMCCC
registers (starting from a2):

  pkvm_hyp_req_to_smccc() to encode into the SMCCC args.
  smccc_to_pkvm_hyp_req() to decode them.

When the hypervisor raises a request, the host must handle it and retry
the HVC. To automate this sequence, introduce the pkvm_call_hyp_req()
macro. This intercepts pending requests, invokes the handler and retries
the HVC.

Additionally, introduce a trace event to track the handling of these
requests.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Link: https://patch.msgid.link/20261001142849.3367614-7-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>

0 files changed, 0 insertions, 0 deletions