OvmfPkg/Library/XenHypercallLib/XenHypercall.c

   1 /** @file
   2   Functions to make Xen hypercalls.
   3
   4   Copyright (C) 2014, Citrix Ltd.
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include <PiDxe.h>
  11
  12 #include <IndustryStandard/Xen/hvm/params.h>
  13 #include <IndustryStandard/Xen/memory.h>
  14
  15 #include <Library/DebugLib.h>
  16 #include <Library/XenHypercallLib.h>
  17
  18 RETURN_STATUS
  19 EFIAPI
  20 XenHypercallLibConstruct (
  21   VOID
  22   )
  23 {
  24   XenHypercallLibInit ();
  25   //
  26   // We don't fail library construction, since that has catastrophic
  27   // consequences for client modules (whereas those modules may easily be
  28   // running on a non-Xen platform). Instead, XenHypercallIsAvailable()
  29   // will return FALSE.
  30   //
  31   return RETURN_SUCCESS;
  32 }
  33
  34 UINT64
  35 EFIAPI
  36 XenHypercallHvmGetParam (
  37   IN UINT32        Index
  38   )
  39 {
  40   xen_hvm_param_t     Parameter;
  41   INTN                Error;
  42
  43   Parameter.domid = DOMID_SELF;
  44   Parameter.index = Index;
  45   Error = XenHypercall2 (__HYPERVISOR_hvm_op,
  46                          HVMOP_get_param, (INTN) &Parameter);
  47   if (Error != 0) {
  48     DEBUG ((EFI_D_ERROR,
  49             "XenHypercall: Error %Ld trying to get HVM parameter %d\n",
  50             (INT64)Error, Index));
  51     return 0;
  52   }
  53   return Parameter.value;
  54 }
  55
  56 INTN
  57 EFIAPI
  58 XenHypercallMemoryOp (
  59   IN     UINTN Operation,
  60   IN OUT VOID *Arguments
  61   )
  62 {
  63   return XenHypercall2 (__HYPERVISOR_memory_op,
  64                         Operation, (INTN) Arguments);
  65 }
  66
  67 INTN
  68 EFIAPI
  69 XenHypercallEventChannelOp (
  70   IN     INTN Operation,
  71   IN OUT VOID *Arguments
  72   )
  73 {
  74   return XenHypercall2 (__HYPERVISOR_event_channel_op,
  75                         Operation, (INTN) Arguments);
  76 }