audk/IntelFsp2WrapperPkg/FspWrapperNotifyDxe/LoadBelow4G.c

153 lines
4.8 KiB
C
Raw Normal View History

/** @file
IntelFsp2WrapperPkg: Refine casting expression result to bigger size There are cases that the operands of an expression are all with rank less than UINT64/INT64 and the result of the expression is explicitly cast to UINT64/INT64 to fit the target size. An example will be: UINT32 a,b; // a and b can be any unsigned int type with rank less than UINT64, like // UINT8, UINT16, etc. UINT64 c; c = (UINT64) (a + b); Some static code checkers may warn that the expression result might overflow within the rank of "int" (integer promotions) and the result is then cast to a bigger size. The commit refines codes by the following rules: 1). When the expression is possible to overflow the range of unsigned int/ int: c = (UINT64)a + b; 2). When the expression will not overflow within the rank of "int", remove the explicit type casts: c = a + b; 3). When the expression will be cast to pointer of possible greater size: UINT32 a,b; VOID *c; c = (VOID *)(UINTN)(a + b); --> c = (VOID *)((UINTN)a + b); 4). When one side of a comparison expression contains only operands with rank less than UINT32: UINT8 a; UINT16 b; UINTN c; if ((UINTN)(a + b) > c) {...} --> if (((UINT32)a + b) > c) {...} For rule 4), if we remove the 'UINTN' type cast like: if (a + b > c) {...} The VS compiler will complain with warning C4018 (signed/unsigned mismatch, level 3 warning) due to promoting 'a + b' to type 'int'. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Hao Wu <hao.a.wu@intel.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
2017-02-15 06:51:01 +01:00
Copyright (c) 2015 - 2017, Intel Corporation. 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 <Uefi.h>
#include <Library/BaseLib.h>
#include <Library/UefiDriverEntryPoint.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/PeCoffLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/DxeServicesLib.h>
#include <Library/CacheMaintenanceLib.h>
#include <Library/UefiLib.h>
/**
Relocate this image under 4G memory.
@param ImageHandle Handle of driver image.
@param SystemTable Pointer to system table.
@retval EFI_SUCCESS Image successfully relocated.
@retval EFI_ABORTED Failed to relocate image.
**/
EFI_STATUS
RelocateImageUnder4GIfNeeded (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
UINT8 *Buffer;
UINTN BufferSize;
EFI_HANDLE NewImageHandle;
UINTN Pages;
EFI_PHYSICAL_ADDRESS FfsBuffer;
PE_COFF_LOADER_IMAGE_CONTEXT ImageContext;
VOID *Interface;
//
// If it is already <4G, no need do relocate
//
if ((UINTN)RelocateImageUnder4GIfNeeded < 0xFFFFFFFF) {
return EFI_SUCCESS;
}
//
// If locate gEfiCallerIdGuid success, it means 2nd entry.
//
Status = gBS->LocateProtocol (&gEfiCallerIdGuid, NULL, &Interface);
if (!EFI_ERROR (Status)) {
DEBUG ((DEBUG_INFO, "FspNotifyDxe - 2nd entry\n"));
return EFI_SUCCESS;
}
DEBUG ((DEBUG_INFO, "FspNotifyDxe - 1st entry\n"));
//
// Here we install a dummy handle
//
NewImageHandle = NULL;
Status = gBS->InstallProtocolInterface (
&NewImageHandle,
&gEfiCallerIdGuid,
EFI_NATIVE_INTERFACE,
NULL
);
ASSERT_EFI_ERROR (Status);
//
// Reload image itself to <4G mem
//
Status = GetSectionFromAnyFv (
&gEfiCallerIdGuid,
EFI_SECTION_PE32,
0,
(VOID **) &Buffer,
&BufferSize
);
ASSERT_EFI_ERROR (Status);
ImageContext.Handle = Buffer;
ImageContext.ImageRead = PeCoffLoaderImageReadFromMemory;
//
// Get information about the image being loaded
//
Status = PeCoffLoaderGetImageInfo (&ImageContext);
ASSERT_EFI_ERROR (Status);
if (ImageContext.SectionAlignment > EFI_PAGE_SIZE) {
Pages = EFI_SIZE_TO_PAGES ((UINTN) (ImageContext.ImageSize + ImageContext.SectionAlignment));
} else {
Pages = EFI_SIZE_TO_PAGES ((UINTN) ImageContext.ImageSize);
}
FfsBuffer = 0xFFFFFFFF;
Status = gBS->AllocatePages (
AllocateMaxAddress,
EfiBootServicesCode,
Pages,
&FfsBuffer
);
ASSERT_EFI_ERROR (Status);
ImageContext.ImageAddress = (PHYSICAL_ADDRESS)(UINTN)FfsBuffer;
//
// Align buffer on section boundary
//
ImageContext.ImageAddress += ImageContext.SectionAlignment - 1;
IntelFsp2WrapperPkg: Refine casting expression result to bigger size There are cases that the operands of an expression are all with rank less than UINT64/INT64 and the result of the expression is explicitly cast to UINT64/INT64 to fit the target size. An example will be: UINT32 a,b; // a and b can be any unsigned int type with rank less than UINT64, like // UINT8, UINT16, etc. UINT64 c; c = (UINT64) (a + b); Some static code checkers may warn that the expression result might overflow within the rank of "int" (integer promotions) and the result is then cast to a bigger size. The commit refines codes by the following rules: 1). When the expression is possible to overflow the range of unsigned int/ int: c = (UINT64)a + b; 2). When the expression will not overflow within the rank of "int", remove the explicit type casts: c = a + b; 3). When the expression will be cast to pointer of possible greater size: UINT32 a,b; VOID *c; c = (VOID *)(UINTN)(a + b); --> c = (VOID *)((UINTN)a + b); 4). When one side of a comparison expression contains only operands with rank less than UINT32: UINT8 a; UINT16 b; UINTN c; if ((UINTN)(a + b) > c) {...} --> if (((UINT32)a + b) > c) {...} For rule 4), if we remove the 'UINTN' type cast like: if (a + b > c) {...} The VS compiler will complain with warning C4018 (signed/unsigned mismatch, level 3 warning) due to promoting 'a + b' to type 'int'. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Hao Wu <hao.a.wu@intel.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
2017-02-15 06:51:01 +01:00
ImageContext.ImageAddress &= ~((EFI_PHYSICAL_ADDRESS)ImageContext.SectionAlignment - 1);
//
// Load the image to our new buffer
//
Status = PeCoffLoaderLoadImage (&ImageContext);
ASSERT_EFI_ERROR (Status);
//
// Relocate the image in our new buffer
//
Status = PeCoffLoaderRelocateImage (&ImageContext);
ASSERT_EFI_ERROR (Status);
//
// Free the buffer allocated by ReadSection since the image has been relocated in the new buffer
//
gBS->FreePool (Buffer);
//
// Flush the instruction cache so the image data is written before we execute it
//
InvalidateInstructionCacheRange ((VOID *)(UINTN)ImageContext.ImageAddress, (UINTN)ImageContext.ImageSize);
DEBUG ((DEBUG_INFO, "Loading driver at 0x%08x EntryPoint=0x%08x\n", (UINTN)ImageContext.ImageAddress, (UINTN)ImageContext.EntryPoint));
Status = ((EFI_IMAGE_ENTRY_POINT)(UINTN)(ImageContext.EntryPoint)) (NewImageHandle, gST);
if (EFI_ERROR (Status)) {
DEBUG ((DEBUG_ERROR, "Error: Image at 0x%08x start failed: %r\n", ImageContext.ImageAddress, Status));
gBS->FreePages (FfsBuffer, Pages);
}
//
// return error to unload >4G copy, if we already relocate itself to <4G.
//
return EFI_ALREADY_STARTED;
}