OvmfPkg/Xen*: Pass struct XENSTORE_TRANSACTION argument as a pointer

[mirror_edk2.git] / OvmfPkg / XenBusDxe / XenBus.c

/** @file\r
  XenBus Bus driver implemtation.\r
\r
  This file implement the necessary to discover and enumerate Xen PV devices\r
  through XenStore.\r
\r
  Copyright (C) 2010 Spectra Logic Corporation\r
  Copyright (C) 2008 Doug Rabson\r
  Copyright (C) 2005 Rusty Russell, IBM Corporation\r
  Copyright (C) 2005 Mike Wray, Hewlett-Packard\r
  Copyright (C) 2005 XenSource Ltd\r
  Copyright (C) 2014, Citrix Ltd.\r
\r
  This file may be distributed separately from the Linux kernel, or\r
  incorporated into other software packages, subject to the following license:\r
\r
  Permission is hereby granted, free of charge, to any person obtaining a copy\r
  of this source file (the "Software"), to deal in the Software without\r
  restriction, including without limitation the rights to use, copy, modify,\r
  merge, publish, distribute, sublicense, and/or sell copies of the Software,\r
  and to permit persons to whom the Software is furnished to do so, subject to\r
  the following conditions:\r
\r
  The above copyright notice and this permission notice shall be included in\r
  all copies or substantial portions of the Software.\r
\r
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\r
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\r
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\r
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\r
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING\r
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS\r
  IN THE SOFTWARE.\r
**/\r
\r
#include <Library/PrintLib.h>\r
\r
#include "XenBus.h"\r
#include "GrantTable.h"\r
#include "XenStore.h"\r
#include "EventChannel.h"\r
\r
#include <IndustryStandard/Xen/io/xenbus.h>\r
\r
STATIC XENBUS_PRIVATE_DATA gXenBusPrivateData;\r
\r
STATIC XENBUS_DEVICE_PATH gXenBusDevicePathTemplate = {\r
  .Vendor.Header.Type = HARDWARE_DEVICE_PATH,\r
  .Vendor.Header.SubType = HW_VENDOR_DP,\r
  .Vendor.Header.Length[0] = (UINT8) sizeof (XENBUS_DEVICE_PATH),\r
  .Vendor.Header.Length[1] = (UINT8) (sizeof (XENBUS_DEVICE_PATH) >> 8),\r
  .Vendor.Guid = XENBUS_PROTOCOL_GUID,\r
  .Type = 0,\r
  .DeviceId = 0\r
};\r
\r
\r
/**\r
  Search our internal record of configured devices (not the XenStore) to\r
  determine if the XenBus device indicated by Node is known to the system.\r
\r
  @param Dev   The XENBUS_DEVICE instance to search for device children.\r
  @param Node  The XenStore node path for the device to find.\r
\r
  @return  The XENBUS_PRIVATE_DATA of the found device if any, or NULL.\r
 */\r
STATIC\r
XENBUS_PRIVATE_DATA *\r
XenBusDeviceInitialized (\r
  IN XENBUS_DEVICE *Dev,\r
  IN CONST CHAR8 *Node\r
  )\r
{\r
  LIST_ENTRY *Entry;\r
  XENBUS_PRIVATE_DATA *Child;\r
  XENBUS_PRIVATE_DATA *Result;\r
\r
  if (IsListEmpty (&Dev->ChildList)) {\r
    return NULL;\r
  }\r
\r
  Result = NULL;\r
  for (Entry = GetFirstNode (&Dev->ChildList);\r
       !IsNodeAtEnd (&Dev->ChildList, Entry);\r
       Entry = GetNextNode (&Dev->ChildList, Entry)) {\r
    Child = XENBUS_PRIVATE_DATA_FROM_LINK (Entry);\r
    if (!AsciiStrCmp (Child->XenBusIo.Node, Node)) {\r
      Result = Child;\r
      break;\r
    }\r
  }\r
\r
  return (Result);\r
}\r
\r
STATIC\r
XenbusState\r
XenBusReadDriverState (\r
  IN CONST CHAR8 *Path\r
  )\r
{\r
  XenbusState State;\r
  CHAR8 *Ptr = NULL;\r
  XENSTORE_STATUS Status;\r
\r
  Status = XenStoreRead (XST_NIL, Path, "state", NULL, (VOID **)&Ptr);\r
  if (Status != XENSTORE_STATUS_SUCCESS) {\r
    State = XenbusStateClosed;\r
  } else {\r
    State = AsciiStrDecimalToUintn (Ptr);\r
  }\r
\r
  if (Ptr != NULL) {\r
    FreePool (Ptr);\r
  }\r
\r
  return State;\r
}\r
\r
//\r
// Callers should ensure that they are only one calling XenBusAddDevice.\r
//\r
STATIC\r
EFI_STATUS\r
XenBusAddDevice (\r
  XENBUS_DEVICE *Dev,\r
  CONST CHAR8 *Type,\r
  CONST CHAR8 *Id)\r
{\r
  CHAR8 DevicePath[XENSTORE_ABS_PATH_MAX];\r
  XENSTORE_STATUS StatusXenStore;\r
  XENBUS_PRIVATE_DATA *Private;\r
  EFI_STATUS Status;\r
  XENBUS_DEVICE_PATH *TempXenBusPath;\r
  VOID *ChildPciIo;\r
\r
  AsciiSPrint (DevicePath, sizeof (DevicePath),\r
               "device/%a/%a", Type, Id);\r
\r
  if (XenStorePathExists (XST_NIL, DevicePath, "")) {\r
    XENBUS_PRIVATE_DATA *Child;\r
    enum xenbus_state State;\r
    CHAR8 *BackendPath;\r
\r
    Child = XenBusDeviceInitialized (Dev, DevicePath);\r
    if (Child != NULL) {\r
      /*\r
       * We are already tracking this node\r
       */\r
      Status = EFI_SUCCESS;\r
      goto out;\r
    }\r
\r
    State = XenBusReadDriverState (DevicePath);\r
    if (State != XenbusStateInitialising) {\r
      /*\r
       * Device is not new, so ignore it. This can\r
       * happen if a device is going away after\r
       * switching to Closed.\r
       */\r
      DEBUG ((EFI_D_INFO, "XenBus: Device %a ignored. "\r
              "State %d\n", DevicePath, State));\r
      Status = EFI_SUCCESS;\r
      goto out;\r
    }\r
\r
    StatusXenStore = XenStoreRead (XST_NIL, DevicePath, "backend",\r
                                   NULL, (VOID **) &BackendPath);\r
    if (StatusXenStore != XENSTORE_STATUS_SUCCESS) {\r
      DEBUG ((EFI_D_ERROR, "xenbus: %a no backend path.\n", DevicePath));\r
      Status = EFI_NOT_FOUND;\r
      goto out;\r
    }\r
\r
    Private = AllocateCopyPool (sizeof (*Private), &gXenBusPrivateData);\r
    Private->XenBusIo.Type = AsciiStrDup (Type);\r
    Private->XenBusIo.Node = AsciiStrDup (DevicePath);\r
    Private->XenBusIo.Backend = BackendPath;\r
    Private->XenBusIo.DeviceId = AsciiStrDecimalToUintn (Id);\r
    Private->Dev = Dev;\r
\r
    TempXenBusPath = AllocateCopyPool (sizeof (XENBUS_DEVICE_PATH),\r
                                       &gXenBusDevicePathTemplate);\r
    if (!AsciiStrCmp (Private->XenBusIo.Type, "vbd")) {\r
      TempXenBusPath->Type = XENBUS_DEVICE_PATH_TYPE_VBD;\r
    }\r
    TempXenBusPath->DeviceId = Private->XenBusIo.DeviceId;\r
    Private->DevicePath = (XENBUS_DEVICE_PATH *)AppendDevicePathNode (\r
                            Dev->DevicePath,\r
                            &TempXenBusPath->Vendor.Header);\r
    FreePool (TempXenBusPath);\r
\r
    InsertTailList (&Dev->ChildList, &Private->Link);\r
\r
    Status = gBS->InstallMultipleProtocolInterfaces (\r
               &Private->Handle,\r
               &gEfiDevicePathProtocolGuid, Private->DevicePath,\r
               &gXenBusProtocolGuid, &Private->XenBusIo,\r
               NULL);\r
    if (EFI_ERROR (Status)) {\r
      goto ErrorInstallProtocol;\r
    }\r
\r
    Status = gBS->OpenProtocol (Dev->ControllerHandle,\r
               &gEfiPciIoProtocolGuid,\r
               &ChildPciIo, Dev->This->DriverBindingHandle,\r
               Private->Handle,\r
               EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER);\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((EFI_D_ERROR, "open by child controller fail (%r)\n",\r
              Status));\r
      goto ErrorOpenProtocolByChild;\r
    }\r
  } else {\r
    DEBUG ((EFI_D_ERROR, "XenBus: does not exist: %a\n", DevicePath));\r
    Status = EFI_NOT_FOUND;\r
  }\r
\r
  return Status;\r
\r
ErrorOpenProtocolByChild:\r
  gBS->UninstallMultipleProtocolInterfaces (\r
    &Private->Handle,\r
    &gEfiDevicePathProtocolGuid, Private->DevicePath,\r
    &gXenBusProtocolGuid, &Private->XenBusIo,\r
    NULL);\r
ErrorInstallProtocol:\r
  RemoveEntryList (&Private->Link);\r
  FreePool (Private->DevicePath);\r
  FreePool ((VOID *) Private->XenBusIo.Backend);\r
  FreePool ((VOID *) Private->XenBusIo.Node);\r
  FreePool ((VOID *) Private->XenBusIo.Type);\r
  FreePool (Private);\r
out:\r
  return Status;\r
}\r
\r
/**\r
  Enumerate all devices of the given type on this bus.\r
\r
  @param Dev   A XENBUS_DEVICE instance.\r
  @param Type  String indicating the device sub-tree (e.g. "vfb", "vif")\r
               to enumerate.\r
\r
  Devices that are found are been initialize via XenBusAddDevice ().\r
  XenBusAddDevice () ignores duplicate detects and ignores duplicate devices,\r
  so it can be called unconditionally for any device found in the XenStore.\r
 */\r
STATIC\r
VOID\r
XenBusEnumerateDeviceType (\r
  XENBUS_DEVICE *Dev,\r
  CONST CHAR8 *Type\r
  )\r
{\r
  CONST CHAR8 **Directory;\r
  UINTN Index;\r
  UINT32 Count;\r
  XENSTORE_STATUS Status;\r
\r
  Status = XenStoreListDirectory (XST_NIL,\r
                                  "device", Type,\r
                                  &Count, &Directory);\r
  if (Status != XENSTORE_STATUS_SUCCESS) {\r
    return;\r
  }\r
  for (Index = 0; Index < Count; Index++) {\r
    XenBusAddDevice (Dev, Type, Directory[Index]);\r
  }\r
\r
  FreePool (Directory);\r
}\r
\r
\r
/**\r
  Enumerate the devices on a XenBus bus and install a XenBus Protocol instance.\r
\r
  Caller should ensure that it is the only one to call this function. This\r
  function cannot be called concurrently.\r
\r
  @param Dev   A XENBUS_DEVICE instance.\r
\r
  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
           indicating the type of failure.\r
 */\r
XENSTORE_STATUS\r
XenBusEnumerateBus (\r
  XENBUS_DEVICE *Dev\r
  )\r
{\r
  CONST CHAR8 **Types;\r
  UINTN Index;\r
  UINT32 Count;\r
  XENSTORE_STATUS Status;\r
\r
  Status = XenStoreListDirectory (XST_NIL,\r
                                  "device", "",\r
                                  &Count, &Types);\r
  if (Status != XENSTORE_STATUS_SUCCESS) {\r
    return Status;\r
  }\r
\r
  for (Index = 0; Index < Count; Index++) {\r
    XenBusEnumerateDeviceType (Dev, Types[Index]);\r
  }\r
\r
  FreePool (Types);\r
\r
  return XENSTORE_STATUS_SUCCESS;\r
}\r
\r
STATIC\r
XENSTORE_STATUS\r
EFIAPI\r
XenBusSetState (\r
  IN XENBUS_PROTOCOL      *This,\r
  IN CONST XENSTORE_TRANSACTION *Transaction,\r
  IN enum xenbus_state    NewState\r
  )\r
{\r
  enum xenbus_state CurrentState;\r
  XENSTORE_STATUS Status;\r
  CHAR8 *Temp;\r
\r
  DEBUG ((EFI_D_INFO, "XenBus: Set state to %d\n", NewState));\r
\r
  Status = XenStoreRead (Transaction, This->Node, "state", NULL, (VOID **)&Temp);\r
  if (Status != XENSTORE_STATUS_SUCCESS) {\r
    goto Out;\r
  }\r
  CurrentState = AsciiStrDecimalToUintn (Temp);\r
  FreePool (Temp);\r
  if (CurrentState == NewState) {\r
    goto Out;\r
  }\r
\r
  do {\r
    Status = XenStoreSPrint (Transaction, This->Node, "state", "%d", NewState);\r
  } while (Status == XENSTORE_STATUS_EAGAIN);\r
  if (Status != XENSTORE_STATUS_SUCCESS) {\r
    DEBUG ((EFI_D_ERROR, "XenBus: failed to write new state\n"));\r
    goto Out;\r
  }\r
  DEBUG ((EFI_D_INFO, "XenBus: Set state to %d, done\n", NewState));\r
\r
Out:\r
  return Status;\r
}\r
\r
STATIC XENBUS_PRIVATE_DATA gXenBusPrivateData = {\r
  .Signature = XENBUS_PRIVATE_DATA_SIGNATURE,\r
\r
  .XenBusIo.XsRead = XenBusXenStoreRead,\r
  .XenBusIo.XsBackendRead = XenBusXenStoreBackendRead,\r
  .XenBusIo.XsPrintf = XenBusXenStoreSPrint,\r
  .XenBusIo.XsRemove = XenBusXenStoreRemove,\r
  .XenBusIo.XsTransactionStart = XenBusXenStoreTransactionStart,\r
  .XenBusIo.XsTransactionEnd = XenBusXenStoreTransactionEnd,\r
  .XenBusIo.SetState = XenBusSetState,\r
  .XenBusIo.GrantAccess = XenBusGrantAccess,\r
  .XenBusIo.GrantEndAccess = XenBusGrantEndAccess,\r
  .XenBusIo.EventChannelAllocate = XenBusEventChannelAllocate,\r
  .XenBusIo.EventChannelNotify = XenBusEventChannelNotify,\r
  .XenBusIo.EventChannelClose = XenBusEventChannelClose,\r
  .XenBusIo.RegisterWatch = XenBusRegisterWatch,\r
  .XenBusIo.RegisterWatchBackend = XenBusRegisterWatchBackend,\r
  .XenBusIo.UnregisterWatch = XenBusUnregisterWatch,\r
  .XenBusIo.WaitForWatch = XenBusWaitForWatch,\r
\r
  .XenBusIo.Type = NULL,\r
  .XenBusIo.Node = NULL,\r
  .XenBusIo.Backend = NULL,\r
\r
  .Dev = NULL\r
};\r