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 (
  46                       __HYPERVISOR_hvm_op,
  47                       HVMOP_get_param,
  48                       (INTN)&Parameter
  49                       );
  50   if (Error != 0) {
  51     DEBUG ((
  52       DEBUG_ERROR,
  53       "XenHypercall: Error %Ld trying to get HVM parameter %d\n",
  54       (INT64)Error,
  55       Index
  56       ));
  57     return 0;
  58   }
  59
  60   return Parameter.value;
  61 }
  62
  63 INTN
  64 EFIAPI
  65 XenHypercallMemoryOp (
  66   IN     UINTN  Operation,
  67   IN OUT VOID   *Arguments
  68   )
  69 {
  70   return XenHypercall2 (
  71            __HYPERVISOR_memory_op,
  72            Operation,
  73            (INTN)Arguments
  74            );
  75 }
  76
  77 INTN
  78 EFIAPI
  79 XenHypercallEventChannelOp (
  80   IN     INTN  Operation,
  81   IN OUT VOID  *Arguments
  82   )
  83 {
  84   return XenHypercall2 (
  85            __HYPERVISOR_event_channel_op,
  86            Operation,
  87            (INTN)Arguments
  88            );
  89 }