OvmfPkg/XenPvBlkDxe/XenPvBlkDxe.c

   1 /** @file
   2   This driver produce a BlockIo protocol instance for a Xen PV block device.
   3
   4   This driver support XenBus protocol of type 'vbd'. Every function that
   5   comsume XenBus protocol are in BlockFront, which the implementation to access
   6   a Xen PV device. The BlockIo implementation is in it's one file and will call
   7   BlockFront functions.
   8
   9   Copyright (C) 2014, Citrix Ltd.
  10
  11   This program and the accompanying materials
  12   are licensed and made available under the terms and conditions of the BSD License
  13   which accompanies this distribution.  The full text of the license may be found at
  14   http://opensource.org/licenses/bsd-license.php
  15
  16   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  17   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  18
  19 **/
  20
  21 #include "XenPvBlkDxe.h"
  22
  23 #include "BlockFront.h"
  24
  25
  26 ///
  27 /// Driver Binding Protocol instance
  28 ///
  29 EFI_DRIVER_BINDING_PROTOCOL gXenPvBlkDxeDriverBinding = {
  30   XenPvBlkDxeDriverBindingSupported,
  31   XenPvBlkDxeDriverBindingStart,
  32   XenPvBlkDxeDriverBindingStop,
  33   XEN_PV_BLK_DXE_VERSION,
  34   NULL,
  35   NULL
  36 };
  37
  38
  39 /**
  40   Unloads an image.
  41
  42   @param  ImageHandle           Handle that identifies the image to be unloaded.
  43
  44   @retval EFI_SUCCESS           The image has been unloaded.
  45   @retval EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
  46
  47 **/
  48 EFI_STATUS
  49 EFIAPI
  50 XenPvBlkDxeUnload (
  51   IN EFI_HANDLE  ImageHandle
  52   )
  53 {
  54   EFI_STATUS  Status;
  55
  56   EFI_HANDLE  *HandleBuffer;
  57   UINTN       HandleCount;
  58   UINTN       Index;
  59
  60
  61   //
  62   // Retrieve array of all handles in the handle database
  63   //
  64   Status = gBS->LocateHandleBuffer (
  65                   AllHandles,
  66                   NULL,
  67                   NULL,
  68                   &HandleCount,
  69                   &HandleBuffer
  70                   );
  71   if (EFI_ERROR (Status)) {
  72     return Status;
  73   }
  74
  75   //
  76   // Disconnect the current driver from handles in the handle database
  77   //
  78   for (Index = 0; Index < HandleCount; Index++) {
  79     gBS->DisconnectController (HandleBuffer[Index], gImageHandle, NULL);
  80   }
  81
  82   //
  83   // Free the array of handles
  84   //
  85   FreePool (HandleBuffer);
  86
  87
  88   //
  89   // Uninstall protocols installed in the driver entry point
  90   //
  91   Status = gBS->UninstallMultipleProtocolInterfaces (
  92                   ImageHandle,
  93                   &gEfiDriverBindingProtocolGuid, &gXenPvBlkDxeDriverBinding,
  94                   &gEfiComponentNameProtocolGuid,  &gXenPvBlkDxeComponentName,
  95                   &gEfiComponentName2ProtocolGuid, &gXenPvBlkDxeComponentName2,
  96                   NULL
  97                   );
  98   if (EFI_ERROR (Status)) {
  99     return Status;
 100   }
 101
 102   return EFI_SUCCESS;
 103 }
 104
 105 /**
 106   This is the declaration of an EFI image entry point. This entry point is
 107   the same for UEFI Applications, UEFI OS Loaders, and UEFI Drivers including
 108   both device drivers and bus drivers.
 109
 110   @param  ImageHandle           The firmware allocated handle for the UEFI image.
 111   @param  SystemTable           A pointer to the EFI System Table.
 112
 113   @retval EFI_SUCCESS           The operation completed successfully.
 114   @retval Others                An unexpected error occurred.
 115 **/
 116 EFI_STATUS
 117 EFIAPI
 118 XenPvBlkDxeDriverEntryPoint (
 119   IN EFI_HANDLE        ImageHandle,
 120   IN EFI_SYSTEM_TABLE  *SystemTable
 121   )
 122 {
 123   EFI_STATUS  Status;
 124
 125   //
 126   // Install UEFI Driver Model protocol(s).
 127   //
 128   Status = EfiLibInstallDriverBindingComponentName2 (
 129              ImageHandle,
 130              SystemTable,
 131              &gXenPvBlkDxeDriverBinding,
 132              ImageHandle,
 133              &gXenPvBlkDxeComponentName,
 134              &gXenPvBlkDxeComponentName2
 135              );
 136   ASSERT_EFI_ERROR (Status);
 137
 138   return Status;
 139 }
 140
 141
 142 /**
 143   Tests to see if this driver supports a given controller. If a child device is provided,
 144   it further tests to see if this driver supports creating a handle for the specified child device.
 145
 146   This function checks to see if the driver specified by This supports the device specified by
 147   ControllerHandle. Drivers will typically use the device path attached to
 148   ControllerHandle and/or the services from the bus I/O abstraction attached to
 149   ControllerHandle to determine if the driver supports ControllerHandle. This function
 150   may be called many times during platform initialization. In order to reduce boot times, the tests
 151   performed by this function must be very small, and take as little time as possible to execute. This
 152   function must not change the state of any hardware devices, and this function must be aware that the
 153   device specified by ControllerHandle may already be managed by the same driver or a
 154   different driver. This function must match its calls to AllocatePages() with FreePages(),
 155   AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol().
 156   Because ControllerHandle may have been previously started by the same driver, if a protocol is
 157   already in the opened state, then it must not be closed with CloseProtocol(). This is required
 158   to guarantee the state of ControllerHandle is not modified by this function.
 159
 160   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 161   @param[in]  ControllerHandle     The handle of the controller to test. This handle
 162                                    must support a protocol interface that supplies
 163                                    an I/O abstraction to the driver.
 164   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 165                                    parameter is ignored by device drivers, and is optional for bus
 166                                    drivers. For bus drivers, if this parameter is not NULL, then
 167                                    the bus driver must determine if the bus controller specified
 168                                    by ControllerHandle and the child controller specified
 169                                    by RemainingDevicePath are both supported by this
 170                                    bus driver.
 171
 172   @retval EFI_SUCCESS              The device specified by ControllerHandle and
 173                                    RemainingDevicePath is supported by the driver specified by This.
 174   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
 175                                    RemainingDevicePath is already being managed by the driver
 176                                    specified by This.
 177   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
 178                                    RemainingDevicePath is already being managed by a different
 179                                    driver or an application that requires exclusive access.
 180                                    Currently not implemented.
 181   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
 182                                    RemainingDevicePath is not supported by the driver specified by This.
 183 **/
 184 EFI_STATUS
 185 EFIAPI
 186 XenPvBlkDxeDriverBindingSupported (
 187   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 188   IN EFI_HANDLE                   ControllerHandle,
 189   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 190   )
 191 {
 192   EFI_STATUS Status;
 193   XENBUS_PROTOCOL *XenBusIo;
 194
 195   Status = gBS->OpenProtocol (
 196                 ControllerHandle,
 197                 &gXenBusProtocolGuid,
 198                 (VOID **)&XenBusIo,
 199                 This->DriverBindingHandle,
 200                 ControllerHandle,
 201                 EFI_OPEN_PROTOCOL_BY_DRIVER
 202                 );
 203   if (EFI_ERROR (Status)) {
 204     return Status;
 205   }
 206   if (AsciiStrCmp (XenBusIo->Type, "vbd") == 0) {
 207     Status = EFI_SUCCESS;
 208   } else {
 209     Status = EFI_UNSUPPORTED;
 210   }
 211
 212   gBS->CloseProtocol (ControllerHandle, &gXenBusProtocolGuid,
 213                       This->DriverBindingHandle, ControllerHandle);
 214
 215   return Status;
 216 }
 217
 218 /**
 219   Starts a device controller.
 220
 221   The Start() function is designed to be invoked from the EFI boot service ConnectController().
 222   As a result, much of the error checking on the parameters to Start() has been moved into this
 223   common boot service. It is legal to call Start() from other locations,
 224   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 225   1. ControllerHandle must be a valid EFI_HANDLE.
 226   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
 227      EFI_DEVICE_PATH_PROTOCOL.
 228   3. Prior to calling Start(), the Supported() function for the driver specified by This must
 229      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
 230
 231   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 232   @param[in]  ControllerHandle     The handle of the controller to start. This handle
 233                                    must support a protocol interface that supplies
 234                                    an I/O abstraction to the driver.
 235   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
 236                                    parameter is ignored by device drivers, and is optional for bus
 237                                    drivers. For a bus driver, if this parameter is NULL, then handles
 238                                    for all the children of Controller are created by this driver.
 239                                    If this parameter is not NULL and the first Device Path Node is
 240                                    not the End of Device Path Node, then only the handle for the
 241                                    child device specified by the first Device Path Node of
 242                                    RemainingDevicePath is created by this driver.
 243                                    If the first Device Path Node of RemainingDevicePath is
 244                                    the End of Device Path Node, no child handle is created by this
 245                                    driver.
 246
 247   @retval EFI_SUCCESS              The device was started.
 248   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
 249   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
 250   @retval Others                   The driver failded to start the device.
 251
 252 **/
 253 EFI_STATUS
 254 EFIAPI
 255 XenPvBlkDxeDriverBindingStart (
 256   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 257   IN EFI_HANDLE                   ControllerHandle,
 258   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 259   )
 260 {
 261   EFI_STATUS Status;
 262   XENBUS_PROTOCOL *XenBusIo;
 263   XEN_BLOCK_FRONT_DEVICE *Dev;
 264
 265   Status = gBS->OpenProtocol (
 266                 ControllerHandle,
 267                 &gXenBusProtocolGuid,
 268                 (VOID **)&XenBusIo,
 269                 This->DriverBindingHandle,
 270                 ControllerHandle,
 271                 EFI_OPEN_PROTOCOL_BY_DRIVER
 272                 );
 273   if (EFI_ERROR (Status)) {
 274     return Status;
 275   }
 276
 277   Status = XenPvBlockFrontInitialization (XenBusIo, XenBusIo->Node, &Dev);
 278   if (EFI_ERROR (Status)) {
 279     goto CloseProtocol;
 280   }
 281
 282   return EFI_SUCCESS;
 283
 284 CloseProtocol:
 285   gBS->CloseProtocol (ControllerHandle, &gXenBusProtocolGuid,
 286                       This->DriverBindingHandle, ControllerHandle);
 287   return Status;
 288 }
 289
 290 /**
 291   Stops a device controller.
 292
 293   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 294   As a result, much of the error checking on the parameters to Stop() has been moved
 295   into this common boot service. It is legal to call Stop() from other locations,
 296   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 297   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 298      same driver's Start() function.
 299   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 300      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 301      Start() function, and the Start() function must have called OpenProtocol() on
 302      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 303
 304   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 305   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 306                                 support a bus specific I/O protocol for the driver
 307                                 to use to stop the device.
 308   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 309   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 310                                 if NumberOfChildren is 0.
 311
 312   @retval EFI_SUCCESS           The device was stopped.
 313   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 314
 315 **/
 316 EFI_STATUS
 317 EFIAPI
 318 XenPvBlkDxeDriverBindingStop (
 319   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 320   IN EFI_HANDLE                   ControllerHandle,
 321   IN UINTN                        NumberOfChildren,
 322   IN EFI_HANDLE                   *ChildHandleBuffer OPTIONAL
 323   )
 324 {
 325   gBS->CloseProtocol (ControllerHandle, &gXenBusProtocolGuid,
 326          This->DriverBindingHandle, ControllerHandle);
 327
 328   return EFI_SUCCESS;
 329 }