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   XenIo->GrantTableAddress = GrantTableAddress;
  87
  88   XenBusDevicePath = AllocateCopyPool (sizeof *XenBusDevicePath,
  89                        &mXenBusRootDevicePathTemplate);
  90   if (!XenBusDevicePath) {
  91     DEBUG ((EFI_D_ERROR, "%a: Out of memory\n", __FUNCTION__));
  92     Status = EFI_OUT_OF_RESOURCES;
  93     goto FreeXenIo;
  94   }
  95   XenBusDevicePath->GrantTableAddress = GrantTableAddress;
  96
  97   Status = gBS->InstallMultipleProtocolInterfaces (&OutHandle,
  98                   &gEfiDevicePathProtocolGuid, XenBusDevicePath,
  99                   &gXenIoProtocolGuid, XenIo,
 100                   NULL);
 101   if (!EFI_ERROR (Status)) {
 102     *Handle = OutHandle;
 103     return EFI_SUCCESS;
 104   }
 105
 106   DEBUG ((EFI_D_ERROR, "%a: Failed to install the EFI_DEVICE_PATH and "
 107     "XENIO_PROTOCOL protocols on handle %p (Status == %r)\n",
 108     __FUNCTION__, OutHandle, Status));
 109
 110   FreePool (XenBusDevicePath);
 111
 112 FreeXenIo:
 113   FreePool (XenIo);
 114   return Status;
 115 }
 116
 117 /**
 118
 119   Uninstall the XENBUS_ROOT_DEVICE_PATH and XENIO_PROTOCOL protocols
 120
 121   @param  Handle          Handle onto which the protocols have been installed
 122                           earlier by XenIoMmioInstall ()
 123
 124   @retval EFI_SUCCESS     Protocols were uninstalled successfully
 125
 126   @return                 Status code returned by the boot service
 127                           UninstallMultipleProtocolInterfaces ()
 128
 129 **/
 130 EFI_STATUS
 131 XenIoMmioUninstall (
 132   IN       EFI_HANDLE              Handle
 133   )
 134 {
 135   EFI_STATUS    Status;
 136   VOID          *XenIo;
 137   VOID          *XenBusDevicePath;
 138
 139   XenBusDevicePath = NULL;
 140   gBS->OpenProtocol (Handle, &gEfiDevicePathProtocolGuid, &XenBusDevicePath,
 141          NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 142
 143   XenIo = NULL;
 144   gBS->OpenProtocol (Handle, &gXenIoProtocolGuid, &XenIo,
 145          NULL, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
 146
 147   Status = gBS->UninstallMultipleProtocolInterfaces (Handle,
 148                   &gEfiDevicePathProtocolGuid, XenBusDevicePath,
 149                   &gXenIoProtocolGuid, XenIo,
 150                   NULL);
 151
 152   if (EFI_ERROR (Status)) {
 153     return Status;
 154   }
 155
 156   FreePool (XenBusDevicePath);
 157   FreePool (XenIo);
 158
 159   return EFI_SUCCESS;
 160 }