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/** @file
Locate handle functions
Copyright (c) 2006 - 2008, Intel Corporation
All rights reserved. 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 <DxeMain.h>
//
// ProtocolRequest - Last LocateHandle request ID
//
UINTN mEfiLocateHandleRequest = 0;
//
// Internal prototypes
//
typedef struct {
EFI_GUID *Protocol;
VOID *SearchKey;
LIST_ENTRY *Position;
PROTOCOL_ENTRY *ProtEntry;
} LOCATE_POSITION;
typedef
IHANDLE *
(* CORE_GET_NEXT) (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
);
STATIC
IHANDLE *
CoreGetNextLocateAllHandles (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
);
STATIC
IHANDLE *
CoreGetNextLocateByRegisterNotify (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
);
STATIC
IHANDLE *
CoreGetNextLocateByProtocol (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
);
//
//
//
EFI_STATUS
EFIAPI
CoreLocateHandle (
IN EFI_LOCATE_SEARCH_TYPE SearchType,
IN EFI_GUID *Protocol OPTIONAL,
IN VOID *SearchKey OPTIONAL,
IN OUT UINTN *BufferSize,
OUT EFI_HANDLE *Buffer
)
/*++
Routine Description:
Locates the requested handle(s) and returns them in Buffer.
Arguments:
SearchType - The type of search to perform to locate the handles
Protocol - The protocol to search for
SearchKey - Dependant on SearchType
BufferSize - On input the size of Buffer. On output the
size of data returned.
Buffer - The buffer to return the results in
Returns:
EFI_BUFFER_TOO_SMALL - Buffer too small, required buffer size is returned in BufferSize.
EFI_INVALID_PARAMETER - Invalid parameter
EFI_SUCCESS - Successfully found the requested handle(s) and returns them in Buffer.
--*/
{
EFI_STATUS Status;
LOCATE_POSITION Position;
PROTOCOL_NOTIFY *ProtNotify;
CORE_GET_NEXT GetNext;
UINTN ResultSize;
IHANDLE *Handle;
IHANDLE **ResultBuffer;
VOID *Interface;
if (BufferSize == NULL) {
Status = EFI_INVALID_PARAMETER;
}
if ((*BufferSize > 0) && (Buffer == NULL)) {
return EFI_INVALID_PARAMETER;
}
GetNext = NULL;
//
// Set initial position
//
Position.Protocol = Protocol;
Position.SearchKey = SearchKey;
Position.Position = &gHandleList;
ResultSize = 0;
ResultBuffer = (IHANDLE **) Buffer;
Status = EFI_SUCCESS;
//
// Lock the protocol database
//
CoreAcquireProtocolLock ();
//
// Get the search function based on type
//
switch (SearchType) {
case AllHandles:
GetNext = CoreGetNextLocateAllHandles;
break;
case ByRegisterNotify:
//
// Must have SearchKey for locate ByRegisterNotify
//
if (SearchKey == NULL) {
Status = EFI_INVALID_PARAMETER;
break;
}
GetNext = CoreGetNextLocateByRegisterNotify;
break;
case ByProtocol:
GetNext = CoreGetNextLocateByProtocol;
if (Protocol == NULL) {
Status = EFI_INVALID_PARAMETER;
break;
}
//
// Look up the protocol entry and set the head pointer
//
Position.ProtEntry = CoreFindProtocolEntry (Protocol, FALSE);
if (Position.ProtEntry == NULL) {
Status = EFI_NOT_FOUND;
break;
}
Position.Position = &Position.ProtEntry->Protocols;
break;
default:
Status = EFI_INVALID_PARAMETER;
break;
}
if (EFI_ERROR(Status)) {
CoreReleaseProtocolLock ();
return Status;
}
//
// Enumerate out the matching handles
//
mEfiLocateHandleRequest += 1;
for (; ;) {
//
// Get the next handle. If no more handles, stop
//
Handle = GetNext (&Position, &Interface);
if (NULL == Handle) {
break;
}
//
// Increase the resulting buffer size, and if this handle
// fits return it
//
ResultSize += sizeof(Handle);
if (ResultSize <= *BufferSize) {
*ResultBuffer = Handle;
ResultBuffer += 1;
}
}
//
// If the result is a zero length buffer, then there were no
// matching handles
//
if (ResultSize == 0) {
Status = EFI_NOT_FOUND;
} else {
//
// Return the resulting buffer size. If it's larger than what
// was passed, then set the error code
//
if (ResultSize > *BufferSize) {
Status = EFI_BUFFER_TOO_SMALL;
}
*BufferSize = ResultSize;
if (SearchType == ByRegisterNotify && !EFI_ERROR(Status)) {
//
// If this is a search by register notify and a handle was
// returned, update the register notification position
//
ProtNotify = SearchKey;
ProtNotify->Position = ProtNotify->Position->ForwardLink;
}
}
CoreReleaseProtocolLock ();
return Status;
}
STATIC
IHANDLE *
CoreGetNextLocateAllHandles (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
)
/*++
Routine Description:
Routine to get the next Handle, when you are searching for all handles.
Arguments:
Position - Information about which Handle to seach for.
Interface - Return the interface structure for the matching protocol.
Returns:
IHANDLE - An IHANDLE is returned if the next Position is not the end of the
list. A NULL_HANDLE is returned if it's the end of the list.
--*/
{
IHANDLE *Handle;
//
// Next handle
//
Position->Position = Position->Position->ForwardLink;
//
// If not at the end of the list, get the handle
//
Handle = NULL_HANDLE;
*Interface = NULL;
if (Position->Position != &gHandleList) {
Handle = CR (Position->Position, IHANDLE, AllHandles, EFI_HANDLE_SIGNATURE);
}
return Handle;
}
STATIC
IHANDLE *
CoreGetNextLocateByRegisterNotify (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
)
/*++
Routine Description:
Routine to get the next Handle, when you are searching for register protocol
notifies.
Arguments:
Position - Information about which Handle to seach for.
Interface - Return the interface structure for the matching protocol.
Returns:
IHANDLE - An IHANDLE is returned if the next Position is not the end of the
list. A NULL_HANDLE is returned if it's the end of the list.
--*/
{
IHANDLE *Handle;
PROTOCOL_NOTIFY *ProtNotify;
PROTOCOL_INTERFACE *Prot;
LIST_ENTRY *Link;
Handle = NULL_HANDLE;
*Interface = NULL;
ProtNotify = Position->SearchKey;
//
// If this is the first request, get the next handle
//
if (ProtNotify != NULL) {
ASSERT(ProtNotify->Signature == PROTOCOL_NOTIFY_SIGNATURE);
Position->SearchKey = NULL;
//
// If not at the end of the list, get the next handle
//
Link = ProtNotify->Position->ForwardLink;
if (Link != &ProtNotify->Protocol->Protocols) {
Prot = CR (Link, PROTOCOL_INTERFACE, ByProtocol, PROTOCOL_INTERFACE_SIGNATURE);
Handle = (IHANDLE *) Prot->Handle;
*Interface = Prot->Interface;
}
}
return Handle;
}
STATIC
IHANDLE *
CoreGetNextLocateByProtocol (
IN OUT LOCATE_POSITION *Position,
OUT VOID **Interface
)
/*++
Routine Description:
Routine to get the next Handle, when you are searching for a given protocol.
Arguments:
Position - Information about which Handle to seach for.
Interface - Return the interface structure for the matching protocol.
Returns:
IHANDLE - An IHANDLE is returned if the next Position is not the end of the
list. A NULL_HANDLE is returned if it's the end of the list.
--*/
{
IHANDLE *Handle;
LIST_ENTRY *Link;
PROTOCOL_INTERFACE *Prot;
Handle = NULL_HANDLE;
*Interface = NULL;
for (; ;) {
//
// Next entry
//
Link = Position->Position->ForwardLink;
Position->Position = Link;
//
// If not at the end, return the handle
//
if (Link == &Position->ProtEntry->Protocols) {
Handle = NULL_HANDLE;
break;
}
//
// Get the handle
//
Prot = CR(Link, PROTOCOL_INTERFACE, ByProtocol, PROTOCOL_INTERFACE_SIGNATURE);
Handle = (IHANDLE *) Prot->Handle;
*Interface = Prot->Interface;
//
// If this handle has not been returned this request, then
// return it now
//
if (Handle->LocateRequest != mEfiLocateHandleRequest) {
Handle->LocateRequest = mEfiLocateHandleRequest;
break;
}
}
return Handle;
}
EFI_STATUS
EFIAPI
CoreLocateDevicePath (
IN EFI_GUID *Protocol,
IN OUT EFI_DEVICE_PATH_PROTOCOL **DevicePath,
OUT EFI_HANDLE *Device
)
/*++
Routine Description:
Locates the handle to a device on the device path that best matches the specified protocol.
Arguments:
Protocol - The protocol to search for.
DevicePath - On input, a pointer to a pointer to the device path. On output, the device
path pointer is modified to point to the remaining part of the devicepath.
Device - A pointer to the returned device handle.
Returns:
EFI_SUCCESS - The resulting handle was returned.
EFI_NOT_FOUND - No handles matched the search.
EFI_INVALID_PARAMETER - One of the parameters has an invalid value.
--*/
{
INTN SourceSize;
INTN Size;
INTN BestMatch;
UINTN HandleCount;
UINTN Index;
EFI_STATUS Status;
EFI_HANDLE *Handles;
EFI_HANDLE Handle;
EFI_DEVICE_PATH_PROTOCOL *SourcePath;
EFI_DEVICE_PATH_PROTOCOL *TmpDevicePath;
if (Protocol == NULL) {
return EFI_INVALID_PARAMETER;
}
if ((DevicePath == NULL) || (*DevicePath == NULL)) {
return EFI_INVALID_PARAMETER;
}
if (Device == NULL) {
return EFI_INVALID_PARAMETER;
}
*Device = NULL_HANDLE;
SourcePath = *DevicePath;
SourceSize = CoreDevicePathSize (SourcePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL);
//
// The source path can only have 1 instance
//
if (CoreIsDevicePathMultiInstance (SourcePath)) {
DEBUG((EFI_D_ERROR, "LocateDevicePath: Device path has too many instances\n"));
return EFI_INVALID_PARAMETER;
}
//
// Get a list of all handles that support the requested protocol
//
Status = CoreLocateHandleBuffer (ByProtocol, Protocol, NULL, &HandleCount, &Handles);
if (EFI_ERROR (Status) || HandleCount == 0) {
return EFI_NOT_FOUND;
}
BestMatch = -1;
for(Index = 0; Index < HandleCount; Index += 1) {
Handle = Handles[Index];
Status = CoreHandleProtocol (Handle, &gEfiDevicePathProtocolGuid, (VOID **)&TmpDevicePath);
if (EFI_ERROR (Status)) {
//
// If this handle doesn't support device path, then skip it
//
continue;
}
//
// Check if DevicePath is first part of SourcePath
//
Size = CoreDevicePathSize (TmpDevicePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL);
if ((Size <= SourceSize) && CompareMem (SourcePath, TmpDevicePath, Size) == 0) {
//
// If the size is equal to the best match, then we
// have a duplice device path for 2 different device
// handles
//
ASSERT (Size != BestMatch);
//
// We've got a match, see if it's the best match so far
//
if (Size > BestMatch) {
BestMatch = Size;
*Device = Handle;
}
}
}
CoreFreePool (Handles);
//
// If there wasn't any match, then no parts of the device path was found.
// Which is strange since there is likely a "root level" device path in the system.
//
if (BestMatch == -1) {
return EFI_NOT_FOUND;
}
//
// Return the remaining part of the device path
//
*DevicePath = (EFI_DEVICE_PATH_PROTOCOL *) (((UINT8 *) SourcePath) + BestMatch);
return EFI_SUCCESS;
}
EFI_STATUS
EFIAPI
CoreLocateProtocol (
IN EFI_GUID *Protocol,
IN VOID *Registration OPTIONAL,
OUT VOID **Interface
)
/*++
Routine Description:
Return the first Protocol Interface that matches the Protocol GUID. If
Registration is pasased in return a Protocol Instance that was just add
to the system. If Retistration is NULL return the first Protocol Interface
you find.
Arguments:
Protocol - The protocol to search for
Registration - Optional Registration Key returned from RegisterProtocolNotify()
Interface - Return the Protocol interface (instance).
Returns:
EFI_SUCCESS - If a valid Interface is returned
EFI_INVALID_PARAMETER - Invalid parameter
EFI_NOT_FOUND - Protocol interface not found
--*/
{
EFI_STATUS Status;
LOCATE_POSITION Position;
PROTOCOL_NOTIFY *ProtNotify;
IHANDLE *Handle;
if (Interface == NULL) {
return EFI_INVALID_PARAMETER;
}
if (Protocol == NULL) {
return EFI_NOT_FOUND;
}
*Interface = NULL;
Status = EFI_SUCCESS;
//
// Set initial position
//
Position.Protocol = Protocol;
Position.SearchKey = Registration;
Position.Position = &gHandleList;
//
// Lock the protocol database
//
CoreAcquireProtocolLock ();
mEfiLocateHandleRequest += 1;
if (NULL == Registration) {
//
// Look up the protocol entry and set the head pointer
//
Position.ProtEntry = CoreFindProtocolEntry (Protocol, FALSE);
if (Position.ProtEntry == NULL) {
Status = EFI_NOT_FOUND;
goto Done;
}
Position.Position = &Position.ProtEntry->Protocols;
Handle = CoreGetNextLocateByProtocol (&Position, Interface);
} else {
Handle = CoreGetNextLocateByRegisterNotify (&Position, Interface);
}
if (NULL == Handle) {
Status = EFI_NOT_FOUND;
} else if (NULL != Registration) {
//
// If this is a search by register notify and a handle was
// returned, update the register notification position
//
ProtNotify = Registration;
ProtNotify->Position = ProtNotify->Position->ForwardLink;
}
Done:
CoreReleaseProtocolLock ();
return Status;
}
EFI_STATUS
EFIAPI
CoreLocateHandleBuffer (
IN EFI_LOCATE_SEARCH_TYPE SearchType,
IN EFI_GUID *Protocol OPTIONAL,
IN VOID *SearchKey OPTIONAL,
IN OUT UINTN *NumberHandles,
OUT EFI_HANDLE **Buffer
)
/*++
Routine Description:
Function returns an array of handles that support the requested protocol
in a buffer allocated from pool. This is a version of CoreLocateHandle()
that allocates a buffer for the caller.
Arguments:
SearchType - Specifies which handle(s) are to be returned.
Protocol - Provides the protocol to search by.
This parameter is only valid for SearchType ByProtocol.
SearchKey - Supplies the search key depending on the SearchType.
NumberHandles - The number of handles returned in Buffer.
Buffer - A pointer to the buffer to return the requested array of
handles that support Protocol.
Returns:
EFI_SUCCESS - The result array of handles was returned.
EFI_NOT_FOUND - No handles match the search.
EFI_OUT_OF_RESOURCES - There is not enough pool memory to store the matching results.
EFI_INVALID_PARAMETER - Invalid parameter
--*/
{
EFI_STATUS Status;
UINTN BufferSize;
if (NumberHandles == NULL) {
return EFI_INVALID_PARAMETER;
}
if (Buffer == NULL) {
return EFI_INVALID_PARAMETER;
}
BufferSize = 0;
*NumberHandles = 0;
*Buffer = NULL;
Status = CoreLocateHandle (
SearchType,
Protocol,
SearchKey,
&BufferSize,
*Buffer
);
//
// LocateHandleBuffer() returns incorrect status code if SearchType is
// invalid.
//
// Add code to correctly handle expected errors from CoreLocateHandle().
//
if (EFI_ERROR(Status) && Status != EFI_BUFFER_TOO_SMALL) {
if (Status != EFI_INVALID_PARAMETER) {
Status = EFI_NOT_FOUND;
}
return Status;
}
*Buffer = CoreAllocateBootServicesPool (BufferSize);
if (*Buffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
Status = CoreLocateHandle (
SearchType,
Protocol,
SearchKey,
&BufferSize,
*Buffer
);
*NumberHandles = BufferSize/sizeof(EFI_HANDLE);
if (EFI_ERROR(Status)) {
*NumberHandles = 0;
}
return Status;
}
|