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 *  This program and the accompanying materials are
   7 *  licensed and made available under the terms and conditions of the BSD License
   8 *  which accompanies this distribution.  The full text of the license may be found at
   9 *  http://opensource.org/licenses/bsd-license.php
  10 *
  11 *  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12 *  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13 *
  14 **/
  15
  16 #include <Library/BaseLib.h>
  17 #include <Library/UefiBootServicesTableLib.h>
  18 #include <Library/DebugLib.h>
  19 #include <Library/UefiLib.h>
  20 #include <Library/BaseMemoryLib.h>
  21 #include <Library/MemoryAllocationLib.h>
  22 #include <Library/DevicePathLib.h>
  23 #include <Library/XenIoMmioLib.h>
  24
  25 #include <Protocol/XenIo.h>
  26 #include <Guid/XenBusRootDevice.h>
  27
  28 #pragma pack (1)
  29 typedef struct {
  30   VENDOR_DEVICE_PATH                  Vendor;
  31   EFI_PHYSICAL_ADDRESS                GrantTableAddress;
  32   EFI_DEVICE_PATH_PROTOCOL            End;
  33 } XENBUS_ROOT_DEVICE_PATH;
  34 #pragma pack ()
  35
  36 STATIC CONST XENBUS_ROOT_DEVICE_PATH mXenBusRootDevicePathTemplate = {
  37   {
  38     {
  39       HARDWARE_DEVICE_PATH,
  40       HW_VENDOR_DP,
  41       { sizeof (VENDOR_DEVICE_PATH) + sizeof (EFI_PHYSICAL_ADDRESS), 0 }
  42     },
  43     XENBUS_ROOT_DEVICE_GUID,
  44   },
  45   0,
  46   {
  47     END_DEVICE_PATH_TYPE,
  48     END_ENTIRE_DEVICE_PATH_SUBTYPE,
  49     { sizeof (EFI_DEVICE_PATH_PROTOCOL), 0 }
  50   }
  51 };
  52
  53 /**
  54
  55   Install the XENBUS_ROOT_DEVICE_PATH and XENIO_PROTOCOL protocols on
  56   the handle pointed to by @Handle, or on a new handle if it points to
  57   NULL
  58
  59   @param  Handle                Pointer to the handle to install the protocols
  60                                 on, may point to a NULL handle.
  61
  62   @param  GrantTableAddress     The address of the Xen grant table
  63
  64   @retval EFI_SUCCESS           Protocols were installed successfully
  65
  66   @retval EFI_OUT_OF_RESOURCES  The function failed to allocate memory required
  67                                 by the XenIo MMIO and device path protocols
  68
  69   @return                       Status code returned by the boot service
  70                                 InstallMultipleProtocolInterfaces ()
  71
  72 **/
  73 EFI_STATUS
  74 XenIoMmioInstall (
  75   IN OUT   EFI_HANDLE              *Handle,
  76   IN       EFI_PHYSICAL_ADDRESS    GrantTableAddress
  77   )
  78 {
  79   EFI_STATUS                     Status;
  80   XENIO_PROTOCOL                 *XenIo;
  81   XENBUS_ROOT_DEVICE_PATH        *XenBusDevicePath;
  82   EFI_HANDLE                     OutHandle;
  83
  84   ASSERT (Handle != NULL);
  85
  86   OutHandle = *Handle;
  87
  88   XenIo = AllocateZeroPool (sizeof *XenIo);
  89   if (!XenIo) {
  90     return EFI_OUT_OF_RESOURCES;
  91   }
  92   XenIo->GrantTableAddress = GrantTableAddress;
  93
  94   XenBusDevicePath = AllocateCopyPool (sizeof *XenBusDevicePath,
  95                        &mXenBusRootDevicePathTemplate);
  96   if (!XenBusDevicePath) {
  97     DEBUG ((EFI_D_ERROR, "%a: Out of memory\n", __FUNCTION__));
  98     Status = EFI_OUT_OF_RESOURCES;
  99     goto FreeXenIo;
 100   }
 101   XenBusDevicePath->GrantTableAddress = GrantTableAddress;
 102
 103   Status = gBS->InstallMultipleProtocolInterfaces (&OutHandle,
 104                   &gEfiDevicePathProtocolGuid, XenBusDevicePath,
 105                   &gXenIoProtocolGuid, XenIo,
 106                   NULL);
 107   if (!EFI_ERROR (Status)) {
 108     *Handle = OutHandle;
 109     return EFI_SUCCESS;
 110   }
 111
 112   DEBUG ((EFI_D_ERROR, "%a: Failed to install the EFI_DEVICE_PATH and "
 113     "XENIO_PROTOCOL protocols on handle %p (Status == %r)\n",
 114     __FUNCTION__, OutHandle, Status));
 115
 116   FreePool (XenBusDevicePath);
 117
 118 FreeXenIo:
 119   FreePool (XenIo);
 120   return Status;
 121 }
 122
 123 /**
 124
 125   Uninstall the XENBUS_ROOT_DEVICE_PATH and XENIO_PROTOCOL protocols
 126
 127   @param  Handle          Handle onto which the protocols have been installed
 128                           earlier by XenIoMmioInstall ()
 129
 130   @retval EFI_SUCCESS     Protocols were uninstalled successfully
 131
 132   @return                 Status code returned by the boot service
 133                           UninstallMultipleProtocolInterfaces ()
 134
 135 **/
 136 EFI_STATUS
 137 XenIoMmioUninstall (
 138   IN       EFI_HANDLE              Handle
 139   )
 140 {
 141   EFI_STATUS    Status;
 142   VOID          *XenIo;
 143   VOID          *XenBusDevicePath;
 144
 145   XenBusDevicePath = NULL;
 146   gBS->OpenProtocol (Handle, &gEfiDevicePathProtocolGuid, &XenBusDevicePath,
 147          NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 148
 149   XenIo = NULL;
 150   gBS->OpenProtocol (Handle, &gXenIoProtocolGuid, &XenIo,
 151          NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 152
 153   Status = gBS->UninstallMultipleProtocolInterfaces (Handle,
 154                   &gEfiDevicePathProtocolGuid, XenBusDevicePath,
 155                   &gXenIoProtocolGuid, XenIo,
 156                   NULL);
 157
 158   if (EFI_ERROR (Status)) {
 159     return Status;
 160   }
 161
 162   FreePool (XenBusDevicePath);
 163   FreePool (XenIo);
 164
 165   return EFI_SUCCESS;
 166 }