audk/StandaloneMmPkg/Core/Handle.c

/** @file
  SMM handle & protocol handling.

  Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
  Copyright (c) 2016 - 2018, ARM Limited. All rights reserved.<BR>
  This program and the accompanying materials are licensed and made available
  under the terms and conditions of the BSD License which accompanies this
  distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "StandaloneMmCore.h"

//
// mProtocolDatabase     - A list of all protocols in the system.  (simple list for now)
// gHandleList           - A list of all the handles in the system
//
LIST_ENTRY  mProtocolDatabase  = INITIALIZE_LIST_HEAD_VARIABLE (mProtocolDatabase);
LIST_ENTRY  gHandleList        = INITIALIZE_LIST_HEAD_VARIABLE (gHandleList);

/**
  Check whether a handle is a valid EFI_HANDLE

  @param  UserHandle             The handle to check

  @retval EFI_INVALID_PARAMETER  The handle is NULL or not a valid EFI_HANDLE.
  @retval EFI_SUCCESS            The handle is valid EFI_HANDLE.

**/
EFI_STATUS
MmValidateHandle (
  IN EFI_HANDLE  UserHandle
  )
{
  IHANDLE  *Handle;

  Handle = (IHANDLE *)UserHandle;
  if (Handle == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  if (Handle->Signature != EFI_HANDLE_SIGNATURE) {
    return EFI_INVALID_PARAMETER;
  }
  return EFI_SUCCESS;
}

/**
  Finds the protocol entry for the requested protocol.

  @param  Protocol               The ID of the protocol
  @param  Create                 Create a new entry if not found

  @return Protocol entry

**/
PROTOCOL_ENTRY  *
MmFindProtocolEntry (
  IN EFI_GUID   *Protocol,
  IN BOOLEAN    Create
  )
{
  LIST_ENTRY          *Link;
  PROTOCOL_ENTRY      *Item;
  PROTOCOL_ENTRY      *ProtEntry;

  //
  // Search the database for the matching GUID
  //

  ProtEntry = NULL;
  for (Link = mProtocolDatabase.ForwardLink;
       Link != &mProtocolDatabase;
       Link = Link->ForwardLink) {

    Item = CR (Link, PROTOCOL_ENTRY, AllEntries, PROTOCOL_ENTRY_SIGNATURE);
    if (CompareGuid (&Item->ProtocolID, Protocol)) {
      //
      // This is the protocol entry
      //
      ProtEntry = Item;
      break;
    }
  }

  //
  // If the protocol entry was not found and Create is TRUE, then
  // allocate a new entry
  //
  if ((ProtEntry == NULL) && Create) {
    ProtEntry = AllocatePool (sizeof(PROTOCOL_ENTRY));
    if (ProtEntry != NULL) {
      //
      // Initialize new protocol entry structure
      //
      ProtEntry->Signature = PROTOCOL_ENTRY_SIGNATURE;
      CopyGuid ((VOID *)&ProtEntry->ProtocolID, Protocol);
      InitializeListHead (&ProtEntry->Protocols);
      InitializeListHead (&ProtEntry->Notify);

      //
      // Add it to protocol database
      //
      InsertTailList (&mProtocolDatabase, &ProtEntry->AllEntries);
    }
  }
  return ProtEntry;
}

/**
  Finds the protocol instance for the requested handle and protocol.
  Note: This function doesn't do parameters checking, it's caller's responsibility
  to pass in valid parameters.

  @param  Handle                 The handle to search the protocol on
  @param  Protocol               GUID of the protocol
  @param  Interface              The interface for the protocol being searched

  @return Protocol instance (NULL: Not found)

**/
PROTOCOL_INTERFACE *
MmFindProtocolInterface (
  IN IHANDLE   *Handle,
  IN EFI_GUID  *Protocol,
  IN VOID      *Interface
  )
{
  PROTOCOL_INTERFACE  *Prot;
  PROTOCOL_ENTRY      *ProtEntry;
  LIST_ENTRY          *Link;

  Prot = NULL;

  //
  // Lookup the protocol entry for this protocol ID
  //
  ProtEntry = MmFindProtocolEntry (Protocol, FALSE);
  if (ProtEntry != NULL) {
    //
    // Look at each protocol interface for any matches
    //
    for (Link = Handle->Protocols.ForwardLink; Link != &Handle->Protocols; Link=Link->ForwardLink) {
      //
      // If this protocol interface matches, remove it
      //
      Prot = CR (Link, PROTOCOL_INTERFACE, Link, PROTOCOL_INTERFACE_SIGNATURE);
      if (Prot->Interface == Interface && Prot->Protocol == ProtEntry) {
        break;
      }
      Prot = NULL;
    }
  }
  return Prot;
}

/**
  Wrapper function to MmInstallProtocolInterfaceNotify.  This is the public API which
  Calls the private one which contains a BOOLEAN parameter for notifications

  @param  UserHandle             The handle to install the protocol handler on,
                                 or NULL if a new handle is to be allocated
  @param  Protocol               The protocol to add to the handle
  @param  InterfaceType          Indicates whether Interface is supplied in
                                 native form.
  @param  Interface              The interface for the protocol being added

  @return Status code

**/
EFI_STATUS
EFIAPI
MmInstallProtocolInterface (
  IN OUT EFI_HANDLE      *UserHandle,
  IN EFI_GUID            *Protocol,
  IN EFI_INTERFACE_TYPE  InterfaceType,
  IN VOID                *Interface
  )
{
  return MmInstallProtocolInterfaceNotify (
           UserHandle,
           Protocol,
           InterfaceType,
           Interface,
           TRUE
           );
}

/**
  Installs a protocol interface into the boot services environment.

  @param  UserHandle             The handle to install the protocol handler on,
                                 or NULL if a new handle is to be allocated
  @param  Protocol               The protocol to add to the handle
  @param  InterfaceType          Indicates whether Interface is supplied in
                                 native form.
  @param  Interface              The interface for the protocol being added
  @param  Notify                 indicates whether notify the notification list
                                 for this protocol

  @retval EFI_INVALID_PARAMETER  Invalid parameter
  @retval EFI_OUT_OF_RESOURCES   No enough buffer to allocate
  @retval EFI_SUCCESS            Protocol interface successfully installed

**/
EFI_STATUS
MmInstallProtocolInterfaceNotify (
  IN OUT EFI_HANDLE          *UserHandle,
  IN     EFI_GUID            *Protocol,
  IN     EFI_INTERFACE_TYPE  InterfaceType,
  IN     VOID                *Interface,
  IN     BOOLEAN             Notify
  )
{
  PROTOCOL_INTERFACE  *Prot;
  PROTOCOL_ENTRY      *ProtEntry;
  IHANDLE             *Handle;
  EFI_STATUS          Status;
  VOID                *ExistingInterface;

  //
  // returns EFI_INVALID_PARAMETER if InterfaceType is invalid.
  // Also added check for invalid UserHandle and Protocol pointers.
  //
  if (UserHandle == NULL || Protocol == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  if (InterfaceType != EFI_NATIVE_INTERFACE) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Print debug message
  //
  DEBUG ((DEBUG_LOAD | DEBUG_INFO, "MmInstallProtocolInterface: %g %p\n", Protocol, Interface));

  Status = EFI_OUT_OF_RESOURCES;
  Prot = NULL;
  Handle = NULL;

  if (*UserHandle != NULL) {
    Status = MmHandleProtocol (*UserHandle, Protocol, (VOID **)&ExistingInterface);
    if (!EFI_ERROR (Status)) {
      return EFI_INVALID_PARAMETER;
    }
  }

  //
  // Lookup the Protocol Entry for the requested protocol
  //
  ProtEntry = MmFindProtocolEntry (Protocol, TRUE);
  if (ProtEntry == NULL) {
    goto Done;
  }

  //
  // Allocate a new protocol interface structure
  //
  Prot = AllocateZeroPool (sizeof (PROTOCOL_INTERFACE));
  if (Prot == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto Done;
  }

  //
  // If caller didn't supply a handle, allocate a new one
  //
  Handle = (IHANDLE *)*UserHandle;
  if (Handle == NULL) {
    Handle = AllocateZeroPool (sizeof (IHANDLE));
    if (Handle == NULL) {
      Status = EFI_OUT_OF_RESOURCES;
      goto Done;
    }

    //
    // Initialize new handler structure
    //
    Handle->Signature = EFI_HANDLE_SIGNATURE;
    InitializeListHead (&Handle->Protocols);

    //
    // Add this handle to the list global list of all handles
    // in the system
    //
    InsertTailList (&gHandleList, &Handle->AllHandles);
  }

  Status = MmValidateHandle (Handle);
  if (EFI_ERROR (Status)) {
    goto Done;
  }

  //
  // Each interface that is added must be unique
  //
  ASSERT (MmFindProtocolInterface (Handle, Protocol, Interface) == NULL);

  //
  // Initialize the protocol interface structure
  //
  Prot->Signature = PROTOCOL_INTERFACE_SIGNATURE;
  Prot->Handle = Handle;
  Prot->Protocol = ProtEntry;
  Prot->Interface = Interface;

  //
  // Add this protocol interface to the head of the supported
  // protocol list for this handle
  //
  InsertHeadList (&Handle->Protocols, &Prot->Link);

  //
  // Add this protocol interface to the tail of the
  // protocol entry
  //
  InsertTailList (&ProtEntry->Protocols, &Prot->ByProtocol);

  //
  // Notify the notification list for this protocol
  //
  if (Notify) {
    MmNotifyProtocol (Prot);
  }
  Status = EFI_SUCCESS;

Done:
  if (!EFI_ERROR (Status)) {
    //
    // Return the new handle back to the caller
    //
    *UserHandle = Handle;
  } else {
    //
    // There was an error, clean up
    //
    if (Prot != NULL) {
      FreePool (Prot);
    }
  }
  return Status;
}

/**
  Uninstalls all instances of a protocol:interfacer from a handle.
  If the last protocol interface is remove from the handle, the
  handle is freed.

  @param  UserHandle             The handle to remove the protocol handler from
  @param  Protocol               The protocol, of protocol:interface, to remove
  @param  Interface              The interface, of protocol:interface, to remove

  @retval EFI_INVALID_PARAMETER  Protocol is NULL.
  @retval EFI_SUCCESS            Protocol interface successfully uninstalled.

**/
EFI_STATUS
EFIAPI
MmUninstallProtocolInterface (
  IN EFI_HANDLE  UserHandle,
  IN EFI_GUID    *Protocol,
  IN VOID        *Interface
  )
{
  EFI_STATUS          Status;
  IHANDLE             *Handle;
  PROTOCOL_INTERFACE  *Prot;

  //
  // Check that Protocol is valid
  //
  if (Protocol == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Check that UserHandle is a valid handle
  //
  Status = MmValidateHandle (UserHandle);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Check that Protocol exists on UserHandle, and Interface matches the interface in the database
  //
  Prot = MmFindProtocolInterface (UserHandle, Protocol, Interface);
  if (Prot == NULL) {
    return EFI_NOT_FOUND;
  }

  //
  // Remove the protocol interface from the protocol
  //
  Status = EFI_NOT_FOUND;
  Handle = (IHANDLE *)UserHandle;
  Prot   = MmRemoveInterfaceFromProtocol (Handle, Protocol, Interface);

  if (Prot != NULL) {
    //
    // Remove the protocol interface from the handle
    //
    RemoveEntryList (&Prot->Link);

    //
    // Free the memory
    //
    Prot->Signature = 0;
    FreePool (Prot);
    Status = EFI_SUCCESS;
  }

  //
  // If there are no more handlers for the handle, free the handle
  //
  if (IsListEmpty (&Handle->Protocols)) {
    Handle->Signature = 0;
    RemoveEntryList (&Handle->AllHandles);
    FreePool (Handle);
  }
  return Status;
}

/**
  Locate a certain GUID protocol interface in a Handle's protocols.

  @param  UserHandle             The handle to obtain the protocol interface on
  @param  Protocol               The GUID of the protocol

  @return The requested protocol interface for the handle

**/
PROTOCOL_INTERFACE  *
MmGetProtocolInterface (
  IN EFI_HANDLE  UserHandle,
  IN EFI_GUID    *Protocol
  )
{
  EFI_STATUS          Status;
  PROTOCOL_ENTRY      *ProtEntry;
  PROTOCOL_INTERFACE  *Prot;
  IHANDLE             *Handle;
  LIST_ENTRY          *Link;

  Status = MmValidateHandle (UserHandle);
  if (EFI_ERROR (Status)) {
    return NULL;
  }

  Handle = (IHANDLE *)UserHandle;

  //
  // Look at each protocol interface for a match
  //
  for (Link = Handle->Protocols.ForwardLink; Link != &Handle->Protocols; Link = Link->ForwardLink) {
    Prot = CR (Link, PROTOCOL_INTERFACE, Link, PROTOCOL_INTERFACE_SIGNATURE);
    ProtEntry = Prot->Protocol;
    if (CompareGuid (&ProtEntry->ProtocolID, Protocol)) {
      return Prot;
    }
  }
  return NULL;
}

/**
  Queries a handle to determine if it supports a specified protocol.

  @param  UserHandle             The handle being queried.
  @param  Protocol               The published unique identifier of the protocol.
  @param  Interface              Supplies the address where a pointer to the
                                 corresponding Protocol Interface is returned.

  @retval EFI_SUCCESS            The interface information for the specified protocol was returned.
  @retval EFI_UNSUPPORTED        The device does not support the specified protocol.
  @retval EFI_INVALID_PARAMETER  Handle is not a valid EFI_HANDLE..
  @retval EFI_INVALID_PARAMETER  Protocol is NULL.
  @retval EFI_INVALID_PARAMETER  Interface is NULL.

**/
EFI_STATUS
EFIAPI
MmHandleProtocol (
  IN  EFI_HANDLE  UserHandle,
  IN  EFI_GUID    *Protocol,
  OUT VOID        **Interface
  )
{
  EFI_STATUS          Status;
  PROTOCOL_INTERFACE  *Prot;

  //
  // Check for invalid Protocol
  //
  if (Protocol == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Check for invalid Interface
  //
  if (Interface == NULL) {
    return EFI_INVALID_PARAMETER;
  } else {
    *Interface = NULL;
  }

  //
  // Check for invalid UserHandle
  //
  Status = MmValidateHandle (UserHandle);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Look at each protocol interface for a match
  //
  Prot = MmGetProtocolInterface (UserHandle, Protocol);
  if (Prot == NULL) {
    return EFI_UNSUPPORTED;
  }

  //
  // This is the protocol interface entry for this protocol
  //
  *Interface = Prot->Interface;

  return EFI_SUCCESS;
}