audk/OvmfPkg/Include/Library/XenHypercallLib.h

/** @file
  Functions declarations to make Xen hypercalls.

  Copyright (C) 2014, Citrix Ltd.

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#ifndef __XEN_HYPERCALL_LIB_H__
#define __XEN_HYPERCALL_LIB_H__

/**
  Check if the Xen Hypercall library is able to make calls to the Xen
  hypervisor.

  Client code should call further functions in this library only if, and after,
  this function returns TRUE.

  @retval TRUE   Hypercalls are available.
  @retval FALSE  Hypercalls are not available.
**/
BOOLEAN
EFIAPI
XenHypercallIsAvailable (
  VOID
  );

/**
  This function will put the two arguments in the right place (registers) and
  invoke the hypercall identified by HypercallID.

  @param HypercallID    The symbolic ID of the hypercall to be invoked
  @param Arg1           First argument.
  @param Arg2           Second argument.

  @return   Return 0 if success otherwise it return an errno.
**/
INTN
EFIAPI
XenHypercall2 (
  IN     UINTN  HypercallID,
  IN OUT INTN   Arg1,
  IN OUT INTN   Arg2
  );

/**
  Return the value of the HVM parameter Index.

  @param Index  The parameter to get, e.g. HVM_PARAM_STORE_EVTCHN.

  @return   The value of the asked parameter or 0 in case of error.
**/
UINT64
XenHypercallHvmGetParam (
  UINT32 Index
  );

/**
  Hypercall to do different operation on the memory.

  @param Operation  The operation number, e.g. XENMEM_add_to_physmap.
  @param Arguments  The arguments associated to the operation.

  @return  Return the return value from the hypercall, 0 in case of success
           otherwise, an error code.
**/
INTN
XenHypercallMemoryOp (
  IN     UINTN Operation,
  IN OUT VOID *Arguments
  );

/**
  Do an operation on the event channels.

  @param Operation  The operation number, e.g. EVTCHNOP_send.
  @param Arguments  The argument associated to the operation.

  @return  Return the return value from the hypercall, 0 in case of success
           otherwise, an error code.
**/
INTN
XenHypercallEventChannelOp (
  IN     INTN Operation,
  IN OUT VOID *Arguments
  );

#endif