OvmfPkg/Library/XenIoMmioLib/XenIoMmioLib.c

   1 /** @file
   2 *  Manage XenBus device path and I/O handles
   3 *
   4 *  Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR>
   5 *
   6 *  SPDX-License-Identifier: BSD-2-Clause-Patent
   7 *
   8 **/
   9
  10 #include <Library/BaseLib.h>
  11 #include <Library/UefiBootServicesTableLib.h>
  12 #include <Library/DebugLib.h>
  13 #include <Library/UefiLib.h>
  14 #include <Library/BaseMemoryLib.h>
  15 #include <Library/MemoryAllocationLib.h>
  16 #include <Library/DevicePathLib.h>
  17 #include <Library/XenIoMmioLib.h>
  18
  19 #include <Protocol/XenIo.h>
  20 #include <Guid/XenBusRootDevice.h>
  21
  22 #pragma pack (1)
  23 typedef struct {
  24   VENDOR_DEVICE_PATH          Vendor;
  25   EFI_PHYSICAL_ADDRESS        GrantTableAddress;
  26   EFI_DEVICE_PATH_PROTOCOL    End;
  27 } XENBUS_ROOT_DEVICE_PATH;
  28 #pragma pack ()
  29
  30 STATIC CONST XENBUS_ROOT_DEVICE_PATH  mXenBusRootDevicePathTemplate = {
  31   {
  32     {
  33       HARDWARE_DEVICE_PATH,
  34       HW_VENDOR_DP,
  35       { sizeof (VENDOR_DEVICE_PATH) + sizeof (EFI_PHYSICAL_ADDRESS), 0 }
  36     },
  37     XENBUS_ROOT_DEVICE_GUID,
  38   },
  39   0,
  40   {
  41     END_DEVICE_PATH_TYPE,
  42     END_ENTIRE_DEVICE_PATH_SUBTYPE,
  43     { sizeof (EFI_DEVICE_PATH_PROTOCOL),                           0 }
  44   }
  45 };
  46
  47 /**
  48
  49   Install the XENBUS_ROOT_DEVICE_PATH and XENIO_PROTOCOL protocols on
  50   the handle pointed to by @Handle, or on a new handle if it points to
  51   NULL
  52
  53   @param  Handle                Pointer to the handle to install the protocols
  54                                 on, may point to a NULL handle.
  55
  56   @param  GrantTableAddress     The address of the Xen grant table
  57
  58   @retval EFI_SUCCESS           Protocols were installed successfully
  59
  60   @retval EFI_OUT_OF_RESOURCES  The function failed to allocate memory required
  61                                 by the XenIo MMIO and device path protocols
  62
  63   @return                       Status code returned by the boot service
  64                                 InstallMultipleProtocolInterfaces ()
  65
  66 **/
  67 EFI_STATUS
  68 XenIoMmioInstall (
  69   IN OUT   EFI_HANDLE            *Handle,
  70   IN       EFI_PHYSICAL_ADDRESS  GrantTableAddress
  71   )
  72 {
  73   EFI_STATUS               Status;
  74   XENIO_PROTOCOL           *XenIo;
  75   XENBUS_ROOT_DEVICE_PATH  *XenBusDevicePath;
  76   EFI_HANDLE               OutHandle;
  77
  78   ASSERT (Handle != NULL);
  79
  80   OutHandle = *Handle;
  81
  82   XenIo = AllocateZeroPool (sizeof *XenIo);
  83   if (!XenIo) {
  84     return EFI_OUT_OF_RESOURCES;
  85   }
  86
  87   XenIo->GrantTableAddress = GrantTableAddress;
  88
  89   XenBusDevicePath = AllocateCopyPool (
  90                        sizeof *XenBusDevicePath,
  91                        &mXenBusRootDevicePathTemplate
  92                        );
  93   if (!XenBusDevicePath) {
  94     DEBUG ((DEBUG_ERROR, "%a: Out of memory\n", __FUNCTION__));
  95     Status = EFI_OUT_OF_RESOURCES;
  96     goto FreeXenIo;
  97   }
  98
  99   XenBusDevicePath->GrantTableAddress = GrantTableAddress;
 100
 101   Status = gBS->InstallMultipleProtocolInterfaces (
 102                   &OutHandle,
 103                   &gEfiDevicePathProtocolGuid,
 104                   XenBusDevicePath,
 105                   &gXenIoProtocolGuid,
 106                   XenIo,
 107                   NULL
 108                   );
 109   if (!EFI_ERROR (Status)) {
 110     *Handle = OutHandle;
 111     return EFI_SUCCESS;
 112   }
 113
 114   DEBUG ((
 115     DEBUG_ERROR,
 116     "%a: Failed to install the EFI_DEVICE_PATH and "
 117     "XENIO_PROTOCOL protocols on handle %p (Status == %r)\n",
 118     __FUNCTION__,
 119     OutHandle,
 120     Status
 121     ));
 122
 123   FreePool (XenBusDevicePath);
 124
 125 FreeXenIo:
 126   FreePool (XenIo);
 127   return Status;
 128 }
 129
 130 /**
 131
 132   Uninstall the XENBUS_ROOT_DEVICE_PATH and XENIO_PROTOCOL protocols
 133
 134   @param  Handle          Handle onto which the protocols have been installed
 135                           earlier by XenIoMmioInstall ()
 136
 137   @retval EFI_SUCCESS     Protocols were uninstalled successfully
 138
 139   @return                 Status code returned by the boot service
 140                           UninstallMultipleProtocolInterfaces ()
 141
 142 **/
 143 EFI_STATUS
 144 XenIoMmioUninstall (
 145   IN       EFI_HANDLE  Handle
 146   )
 147 {
 148   EFI_STATUS  Status;
 149   VOID        *XenIo;
 150   VOID        *XenBusDevicePath;
 151
 152   XenBusDevicePath = NULL;
 153   gBS->OpenProtocol (
 154          Handle,
 155          &gEfiDevicePathProtocolGuid,
 156          &XenBusDevicePath,
 157          NULL,
 158          NULL,
 159          EFI_OPEN_PROTOCOL_GET_PROTOCOL
 160          );
 161
 162   XenIo = NULL;
 163   gBS->OpenProtocol (
 164          Handle,
 165          &gXenIoProtocolGuid,
 166          &XenIo,
 167          NULL,
 168          NULL,
 169          EFI_OPEN_PROTOCOL_GET_PROTOCOL
 170          );
 171
 172   Status = gBS->UninstallMultipleProtocolInterfaces (
 173                   Handle,
 174                   &gEfiDevicePathProtocolGuid,
 175                   XenBusDevicePath,
 176                   &gXenIoProtocolGuid,
 177                   XenIo,
 178                   NULL
 179                   );
 180
 181   if (EFI_ERROR (Status)) {
 182     return Status;
 183   }
 184
 185   FreePool (XenBusDevicePath);
 186   FreePool (XenIo);
 187
 188   return EFI_SUCCESS;
 189 }