audk/OvmfPkg/Library/XenHypercallLib/XenHypercall.c

/** @file
  Functions to make Xen hypercalls.

  Copyright (C) 2014, Citrix Ltd.

  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <PiDxe.h>

#include <IndustryStandard/Xen/hvm/params.h>
#include <IndustryStandard/Xen/memory.h>

#include <Library/DebugLib.h>
#include <Library/XenHypercallLib.h>

RETURN_STATUS
EFIAPI
XenHypercallLibConstruct (
  VOID
  )
{
  XenHypercallLibInit ();
  //
  // We don't fail library construction, since that has catastrophic
  // consequences for client modules (whereas those modules may easily be
  // running on a non-Xen platform). Instead, XenHypercallIsAvailable()
  // will return FALSE.
  //
  return RETURN_SUCCESS;
}

UINT64
EFIAPI
XenHypercallHvmGetParam (
  IN UINT32        Index
  )
{
  xen_hvm_param_t     Parameter;
  INTN                Error;

  Parameter.domid = DOMID_SELF;
  Parameter.index = Index;
  Error = XenHypercall2 (__HYPERVISOR_hvm_op,
                         HVMOP_get_param, (INTN) &Parameter);
  if (Error != 0) {
    DEBUG ((EFI_D_ERROR,
            "XenHypercall: Error %Ld trying to get HVM parameter %d\n",
            (INT64)Error, Index));
    return 0;
  }
  return Parameter.value;
}

INTN
EFIAPI
XenHypercallMemoryOp (
  IN     UINTN Operation,
  IN OUT VOID *Arguments
  )
{
  return XenHypercall2 (__HYPERVISOR_memory_op,
                        Operation, (INTN) Arguments);
}

INTN
EFIAPI
XenHypercallEventChannelOp (
  IN     INTN Operation,
  IN OUT VOID *Arguments
  )
{
  return XenHypercall2 (__HYPERVISOR_event_channel_op,
                        Operation, (INTN) Arguments);
}