[mirror_edk2.git] / MdePkg / Library / PeiMemoryAllocationLib / MemoryAllocationLib.c

/** @file\r
  Support routines for memory allocation routines \r
  based on PeiService for PEI phase drivers.\r
\r
  Copyright (c) 2006 - 2008, Intel Corporation<BR>\r
  All rights reserved. This program and the accompanying materials                          \r
  are licensed and made available under the terms and conditions of the BSD License         \r
  which accompanies this distribution.  The full text of the license may be found at        \r
  http://opensource.org/licenses/bsd-license.php                                            \r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
\r
**/\r
\r
\r
#include <PiPei.h>\r
\r
\r
#include <Library/MemoryAllocationLib.h>\r
#include <Library/PeiServicesLib.h>\r
#include <Library/BaseMemoryLib.h>\r
#include <Library/DebugLib.h>\r
\r
\r
/**\r
  Allocates one or more 4KB pages of a certain memory type.\r
\r
  Allocates the number of 4KB pages of a certain memory type and returns a pointer to the allocated\r
  buffer.  The buffer returned is aligned on a 4KB boundary.  If Pages is 0, then NULL is returned.\r
  If there is not enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  @param  MemoryType            The type of memory to allocate.\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalAllocatePages (\r
  IN EFI_MEMORY_TYPE  MemoryType,  \r
  IN UINTN            Pages\r
  )\r
{\r
  EFI_STATUS            Status;\r
  EFI_PHYSICAL_ADDRESS  Memory; \r
\r
  if (Pages == 0) {\r
    return NULL;\r
  }\r
\r
  Status = PeiServicesAllocatePages (MemoryType, Pages, &Memory);\r
  if (EFI_ERROR (Status)) {\r
    return NULL;\r
  }\r
  return (VOID *) (UINTN) Memory;\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiBootServicesData.\r
\r
  Allocates the number of 4KB pages of type EfiBootServicesData and returns a pointer to the\r
  allocated buffer.  The buffer returned is aligned on a 4KB boundary.  If Pages is 0, then NULL\r
  is returned.  If there is not enough memory remaining to satisfy the request, then NULL is\r
  returned.\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocatePages (\r
  IN UINTN  Pages\r
  )\r
{\r
  return InternalAllocatePages (EfiBootServicesData, Pages);\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiRuntimeServicesData.\r
\r
  Allocates the number of 4KB pages of type EfiRuntimeServicesData and returns a pointer to the\r
  allocated buffer.  The buffer returned is aligned on a 4KB boundary.  If Pages is 0, then NULL\r
  is returned.  If there is not enough memory remaining to satisfy the request, then NULL is\r
  returned.\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateRuntimePages (\r
  IN UINTN  Pages\r
  )\r
{\r
  return InternalAllocatePages (EfiRuntimeServicesData, Pages);\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiReservedMemoryType.\r
\r
  Allocates the number of 4KB pages of type EfiReservedMemoryType and returns a pointer to the\r
  allocated buffer.  The buffer returned is aligned on a 4KB boundary.  If Pages is 0, then NULL\r
  is returned.  If there is not enough memory remaining to satisfy the request, then NULL is\r
  returned.\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateReservedPages (\r
  IN UINTN  Pages\r
  )\r
{\r
  return InternalAllocatePages (EfiReservedMemoryType, Pages);\r
}\r
\r
/**\r
  Frees one or more 4KB pages that were previously allocated with one of the page allocation\r
  functions in the Memory Allocation Library.\r
\r
  Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer.  Buffer\r
  must have been allocated on a previous call to the page allocation services of the Memory\r
  Allocation Library.  If it is not possible to free allocated pages, then this function will\r
  perform no actions.\r
  \r
  If Buffer was not allocated with a page allocation function in the Memory Allocation Library,\r
  then ASSERT().\r
  If Pages is zero, then ASSERT().\r
 \r
  @param  Buffer                Pointer to the buffer of pages to free.\r
  @param  Pages                 The number of 4 KB pages to free.\r
\r
**/\r
VOID\r
EFIAPI\r
FreePages (\r
  IN VOID   *Buffer,\r
  IN UINTN  Pages\r
  )\r
{\r
  ASSERT (Pages != 0);\r
  //\r
  // PEI phase does not support to free pages, so leave it as NOP.\r
  //\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of a certain memory type at a specified alignment.\r
\r
  Allocates the number of 4KB pages specified by Pages of a certain memory type with an alignment\r
  specified by Alignment.  The allocated buffer is returned.  If Pages is 0, then NULL is returned.\r
  If there is not enough memory at the specified alignment remaining to satisfy the request, then\r
  NULL is returned.\r
  If Alignment is not a power of two and Alignment is not zero, then ASSERT().\r
\r
  @param  MemoryType            The type of memory to allocate.\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
  @param  Alignment             The requested alignment of the allocation.  Must be a power of two.\r
                                If Alignment is zero, then byte alignment is used.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalAllocateAlignedPages (\r
  IN EFI_MEMORY_TYPE  MemoryType,  \r
  IN UINTN            Pages,\r
  IN UINTN            Alignment\r
  )\r
{\r
  VOID    *Memory;\r
  UINTN   AlignmentMask;\r
\r
  //\r
  // Alignment must be a power of two or zero.\r
  //\r
  ASSERT ((Alignment & (Alignment - 1)) == 0);\r
\r
  if (Pages == 0) {\r
    return NULL;\r
  }\r
  //\r
  // Make sure that Pages plus EFI_SIZE_TO_PAGES (Alignment) does not overflow.\r
  //\r
  ASSERT (Pages <= (MAX_ADDRESS - EFI_SIZE_TO_PAGES (Alignment)));\r
  //\r
  // We would rather waste some memory to save PEI code size.\r
  //\r
  Memory = InternalAllocatePages (MemoryType, Pages + EFI_SIZE_TO_PAGES (Alignment));\r
  if (Alignment == 0) {\r
    AlignmentMask = Alignment;\r
  } else {\r
    AlignmentMask = Alignment - 1;  \r
  }\r
  return (VOID *) (UINTN) (((UINTN) Memory + AlignmentMask) & ~AlignmentMask);\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiBootServicesData at a specified alignment.\r
\r
  Allocates the number of 4KB pages specified by Pages of type EfiBootServicesData with an\r
  alignment specified by Alignment.  The allocated buffer is returned.  If Pages is 0, then NULL is\r
  returned.  If there is not enough memory at the specified alignment remaining to satisfy the\r
  request, then NULL is returned.\r
  \r
  If Alignment is not a power of two and Alignment is not zero, then ASSERT().\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
  @param  Alignment             The requested alignment of the allocation.  Must be a power of two.\r
                                If Alignment is zero, then byte alignment is used.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateAlignedPages (\r
  IN UINTN  Pages,\r
  IN UINTN  Alignment\r
  )\r
{\r
  return InternalAllocateAlignedPages (EfiBootServicesData, Pages, Alignment);\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiRuntimeServicesData at a specified alignment.\r
\r
  Allocates the number of 4KB pages specified by Pages of type EfiRuntimeServicesData with an\r
  alignment specified by Alignment.  The allocated buffer is returned.  If Pages is 0, then NULL is\r
  returned.  If there is not enough memory at the specified alignment remaining to satisfy the\r
  request, then NULL is returned.\r
  \r
  If Alignment is not a power of two and Alignment is not zero, then ASSERT().\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
  @param  Alignment             The requested alignment of the allocation.  Must be a power of two.\r
                                If Alignment is zero, then byte alignment is used.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateAlignedRuntimePages (\r
  IN UINTN  Pages,\r
  IN UINTN  Alignment\r
  )\r
{\r
  return InternalAllocateAlignedPages (EfiRuntimeServicesData, Pages, Alignment);\r
}\r
\r
/**\r
  Allocates one or more 4KB pages of type EfiReservedMemoryType at a specified alignment.\r
\r
  Allocates the number of 4KB pages specified by Pages of type EfiReservedMemoryType with an\r
  alignment specified by Alignment.  The allocated buffer is returned.  If Pages is 0, then NULL is\r
  returned.  If there is not enough memory at the specified alignment remaining to satisfy the\r
  request, then NULL is returned.\r
  \r
  If Alignment is not a power of two and Alignment is not zero, then ASSERT().\r
\r
  @param  Pages                 The number of 4 KB pages to allocate.\r
  @param  Alignment             The requested alignment of the allocation.  Must be a power of two.\r
                                If Alignment is zero, then byte alignment is used.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateAlignedReservedPages (\r
  IN UINTN  Pages,\r
  IN UINTN  Alignment\r
  )\r
{\r
  return InternalAllocateAlignedPages (EfiReservedMemoryType, Pages, Alignment);\r
}\r
\r
/**\r
  Frees one or more 4KB pages that were previously allocated with one of the aligned page\r
  allocation functions in the Memory Allocation Library.\r
\r
  Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer.  Buffer\r
  must have been allocated on a previous call to the aligned page allocation services of the Memory\r
  Allocation Library.  If it is not possible to free allocated pages, then this function will \r
  perform no actions.\r
  \r
  If Buffer was not allocated with an aligned page allocation function in the Memory Allocation\r
  Library, then ASSERT().\r
  If Pages is zero, then ASSERT().\r
  \r
  @param  Buffer                Pointer to the buffer of pages to free.\r
  @param  Pages                 The number of 4 KB pages to free.\r
\r
**/\r
VOID\r
EFIAPI\r
FreeAlignedPages (\r
  IN VOID   *Buffer,\r
  IN UINTN  Pages\r
  )\r
{\r
  ASSERT (Pages != 0);\r
  //\r
  // PEI phase does not support to free pages, so leave it as NOP.\r
  //\r
}\r
\r
/**\r
  Allocates a buffer of a certain pool type.\r
\r
  Allocates the number bytes specified by AllocationSize of a certain pool type and returns a\r
  pointer to the allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is\r
  returned.  If there is not enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  @param  MemoryType            The type of memory to allocate.\r
  @param  AllocationSize        The number of bytes to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalAllocatePool (\r
  IN EFI_MEMORY_TYPE  MemoryType,  \r
  IN UINTN            AllocationSize\r
  )\r
{\r
  //\r
  // If we need lots of small runtime/reserved memory type from PEI in the future, \r
  // we can consider providing a more complex algorithm that allocates runtime pages and \r
  // provide pool allocations from those pages. \r
  //\r
  return InternalAllocatePages (MemoryType, EFI_SIZE_TO_PAGES (AllocationSize));\r
}\r
\r
/**\r
  Allocates a buffer of type EfiBootServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiBootServicesData and returns a\r
  pointer to the allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is\r
  returned.  If there is not enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocatePool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  EFI_STATUS        Status;\r
  VOID              *Buffer;\r
  \r
  Status = PeiServicesAllocatePool (AllocationSize, &Buffer);\r
  if (EFI_ERROR (Status)) {\r
    Buffer = NULL;\r
  }\r
  return Buffer;\r
}\r
\r
/**\r
  Allocates a buffer of type EfiRuntimeServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData and returns\r
  a pointer to the allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is\r
  returned.  If there is not enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateRuntimePool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  return InternalAllocatePool (EfiRuntimeServicesData, AllocationSize);\r
}\r
\r
/**\r
  Allocates a buffer of type EfiReservedMemoryType.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType and returns\r
  a pointer to the allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is\r
  returned.  If there is not enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateReservedPool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  return InternalAllocatePool (EfiReservedMemoryType, AllocationSize);\r
}\r
\r
/**\r
  Allocates and zeros a buffer of a certain pool type.\r
\r
  Allocates the number bytes specified by AllocationSize of a certain pool type, clears the buffer\r
  with zeros, and returns a pointer to the allocated buffer.  If AllocationSize is 0, then a valid\r
  buffer of 0 size is returned.  If there is not enough memory remaining to satisfy the request,\r
  then NULL is returned.\r
\r
  @param  PoolType              The type of memory to allocate.\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalAllocateZeroPool (\r
  IN EFI_MEMORY_TYPE  PoolType,  \r
  IN UINTN            AllocationSize\r
  ) \r
{\r
  VOID  *Memory;\r
\r
  Memory = InternalAllocatePool (PoolType, AllocationSize);\r
  if (Memory != NULL) {\r
    Memory = ZeroMem (Memory, AllocationSize);\r
  }\r
  return Memory;\r
}\r
\r
/**\r
  Allocates and zeros a buffer of type EfiBootServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiBootServicesData, clears the\r
  buffer with zeros, and returns a pointer to the allocated buffer.  If AllocationSize is 0, then a\r
  valid buffer of 0 size is returned.  If there is not enough memory remaining to satisfy the\r
  request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateZeroPool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  VOID  *Memory;\r
\r
  Memory = AllocatePool (AllocationSize);\r
  if (Memory != NULL) {\r
    Memory = ZeroMem (Memory, AllocationSize);\r
  }\r
  return Memory;\r
}\r
\r
/**\r
  Allocates and zeros a buffer of type EfiRuntimeServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData, clears the\r
  buffer with zeros, and returns a pointer to the allocated buffer.  If AllocationSize is 0, then a\r
  valid buffer of 0 size is returned.  If there is not enough memory remaining to satisfy the\r
  request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateRuntimeZeroPool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  return InternalAllocateZeroPool (EfiRuntimeServicesData, AllocationSize);\r
}\r
\r
/**\r
  Allocates and zeros a buffer of type EfiReservedMemoryType.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType, clears the\r
  buffer with zeros, and returns a pointer to the allocated buffer.  If AllocationSize is 0, then a\r
  valid buffer of 0 size is returned.  If there is not enough memory remaining to satisfy the\r
  request, then NULL is returned.\r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateReservedZeroPool (\r
  IN UINTN  AllocationSize\r
  )\r
{\r
  return InternalAllocateZeroPool (EfiReservedMemoryType, AllocationSize);\r
}\r
\r
/**\r
  Copies a buffer to an allocated buffer of a certain pool type.\r
\r
  Allocates the number bytes specified by AllocationSize of a certain pool type, copies\r
  AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the\r
  allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is returned.  If there\r
  is not enough memory remaining to satisfy the request, then NULL is returned.\r
  If Buffer is NULL, then ASSERT().\r
  If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT(). \r
\r
  @param  PoolType              The type of pool to allocate.\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
  @param  Buffer                The buffer to copy to the allocated buffer.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalAllocateCopyPool (\r
  IN EFI_MEMORY_TYPE  PoolType,  \r
  IN UINTN            AllocationSize,\r
  IN CONST VOID       *Buffer\r
  ) \r
{\r
  VOID  *Memory;\r
\r
  ASSERT (Buffer != NULL);\r
  ASSERT (AllocationSize <= (MAX_ADDRESS - (UINTN) Buffer + 1));\r
\r
  Memory = InternalAllocatePool (PoolType, AllocationSize);\r
  if (Memory != NULL) {\r
     Memory = CopyMem (Memory, Buffer, AllocationSize);\r
  }\r
  return Memory;\r
} \r
\r
/**\r
  Copies a buffer to an allocated buffer of type EfiBootServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiBootServicesData, copies\r
  AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the\r
  allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is returned.  If there\r
  is not enough memory remaining to satisfy the request, then NULL is returned.\r
  \r
  If Buffer is NULL, then ASSERT().\r
  If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT(). \r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
  @param  Buffer                The buffer to copy to the allocated buffer.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateCopyPool (\r
  IN UINTN       AllocationSize,\r
  IN CONST VOID  *Buffer\r
  )\r
{\r
  VOID  *Memory;\r
\r
  ASSERT (Buffer != NULL);\r
  ASSERT (AllocationSize <= (MAX_ADDRESS - (UINTN) Buffer + 1));\r
\r
  Memory = AllocatePool (AllocationSize);\r
  if (Memory != NULL) {\r
     Memory = CopyMem (Memory, Buffer, AllocationSize);\r
  }\r
  return Memory;\r
}\r
\r
/**\r
  Copies a buffer to an allocated buffer of type EfiRuntimeServicesData.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData, copies\r
  AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the\r
  allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is returned.  If there\r
  is not enough memory remaining to satisfy the request, then NULL is returned.\r
  \r
  If Buffer is NULL, then ASSERT().\r
  If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT(). \r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
  @param  Buffer                The buffer to copy to the allocated buffer.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateRuntimeCopyPool (\r
  IN UINTN       AllocationSize,\r
  IN CONST VOID  *Buffer\r
  )\r
{\r
  return InternalAllocateCopyPool (EfiRuntimeServicesData, AllocationSize, Buffer);\r
}\r
\r
/**\r
  Copies a buffer to an allocated buffer of type EfiReservedMemoryType.\r
\r
  Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType, copies\r
  AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the\r
  allocated buffer.  If AllocationSize is 0, then a valid buffer of 0 size is returned.  If there\r
  is not enough memory remaining to satisfy the request, then NULL is returned.\r
  \r
  If Buffer is NULL, then ASSERT().\r
  If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT(). \r
\r
  @param  AllocationSize        The number of bytes to allocate and zero.\r
  @param  Buffer                The buffer to copy to the allocated buffer.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
AllocateReservedCopyPool (\r
  IN UINTN       AllocationSize,\r
  IN CONST VOID  *Buffer\r
  )\r
{\r
  return InternalAllocateCopyPool (EfiReservedMemoryType, AllocationSize, Buffer);\r
}\r
\r
/**\r
  Reallocates a buffer of a specified memory type.\r
\r
  Allocates and zeros the number bytes specified by NewSize from memory of the type\r
  specified by PoolType.  If OldBuffer is not NULL, then the smaller of OldSize and \r
  NewSize bytes are copied from OldBuffer to the newly allocated buffer, and \r
  OldBuffer is freed.  A pointer to the newly allocated buffer is returned.  \r
  If NewSize is 0, then a valid buffer of 0 size is  returned.  If there is not \r
  enough memory remaining to satisfy the request, then NULL is returned.\r
  \r
  If the allocation of the new buffer is successful and the smaller of NewSize and OldSize\r
  is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().\r
\r
  @param  PoolType       The type of pool to allocate.\r
  @param  OldSize        The size, in bytes, of OldBuffer.\r
  @param  NewSize        The size, in bytes, of the buffer to reallocate.\r
  @param  OldBuffer      The buffer to copy to the allocated buffer.  This is an optional \r
                         parameter that may be NULL.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
InternalReallocatePool (\r
  IN EFI_MEMORY_TYPE  PoolType,  \r
  IN UINTN            OldSize,\r
  IN UINTN            NewSize,\r
  IN VOID             *OldBuffer  OPTIONAL\r
  )\r
{\r
  VOID  *NewBuffer;\r
\r
  NewBuffer = InternalAllocateZeroPool (PoolType, NewSize);\r
  if (NewBuffer != NULL && OldBuffer != NULL) {\r
    CopyMem (NewBuffer, OldBuffer, MIN (OldSize, NewSize));\r
    FreePool (OldBuffer);\r
  }\r
  return NewBuffer;\r
}\r
\r
/**\r
  Reallocates a buffer of type EfiBootServicesData.\r
\r
  Allocates and zeros the number bytes specified by NewSize from memory of type\r
  EfiBootServicesData.  If OldBuffer is not NULL, then the smaller of OldSize and \r
  NewSize bytes are copied from OldBuffer to the newly allocated buffer, and \r
  OldBuffer is freed.  A pointer to the newly allocated buffer is returned.  \r
  If NewSize is 0, then a valid buffer of 0 size is  returned.  If there is not \r
  enough memory remaining to satisfy the request, then NULL is returned.\r
  \r
  If the allocation of the new buffer is successful and the smaller of NewSize and OldSize\r
  is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().\r
\r
  @param  OldSize        The size, in bytes, of OldBuffer.\r
  @param  NewSize        The size, in bytes, of the buffer to reallocate.\r
  @param  OldBuffer      The buffer to copy to the allocated buffer.  This is an optional \r
                         parameter that may be NULL.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
ReallocatePool (\r
  IN UINTN  OldSize,\r
  IN UINTN  NewSize,\r
  IN VOID   *OldBuffer  OPTIONAL\r
  )\r
{\r
  return InternalReallocatePool (EfiBootServicesData, OldSize, NewSize, OldBuffer);\r
}\r
\r
/**\r
  Reallocates a buffer of type EfiRuntimeServicesData.\r
\r
  Allocates and zeros the number bytes specified by NewSize from memory of type\r
  EfiRuntimeServicesData.  If OldBuffer is not NULL, then the smaller of OldSize and \r
  NewSize bytes are copied from OldBuffer to the newly allocated buffer, and \r
  OldBuffer is freed.  A pointer to the newly allocated buffer is returned.  \r
  If NewSize is 0, then a valid buffer of 0 size is  returned.  If there is not \r
  enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  If the allocation of the new buffer is successful and the smaller of NewSize and OldSize\r
  is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().\r
\r
  @param  OldSize        The size, in bytes, of OldBuffer.\r
  @param  NewSize        The size, in bytes, of the buffer to reallocate.\r
  @param  OldBuffer      The buffer to copy to the allocated buffer.  This is an optional \r
                         parameter that may be NULL.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
ReallocateRuntimePool (\r
  IN UINTN  OldSize,\r
  IN UINTN  NewSize,\r
  IN VOID   *OldBuffer  OPTIONAL\r
  )\r
{\r
  return InternalReallocatePool (EfiRuntimeServicesData, OldSize, NewSize, OldBuffer);\r
}\r
\r
/**\r
  Reallocates a buffer of type EfiReservedMemoryType.\r
\r
  Allocates and zeros the number bytes specified by NewSize from memory of type\r
  EfiReservedMemoryType.  If OldBuffer is not NULL, then the smaller of OldSize and \r
  NewSize bytes are copied from OldBuffer to the newly allocated buffer, and \r
  OldBuffer is freed.  A pointer to the newly allocated buffer is returned.  \r
  If NewSize is 0, then a valid buffer of 0 size is  returned.  If there is not \r
  enough memory remaining to satisfy the request, then NULL is returned.\r
\r
  If the allocation of the new buffer is successful and the smaller of NewSize and OldSize\r
  is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().\r
\r
  @param  OldSize        The size, in bytes, of OldBuffer.\r
  @param  NewSize        The size, in bytes, of the buffer to reallocate.\r
  @param  OldBuffer      The buffer to copy to the allocated buffer.  This is an optional \r
                         parameter that may be NULL.\r
\r
  @return A pointer to the allocated buffer or NULL if allocation fails.\r
\r
**/\r
VOID *\r
EFIAPI\r
ReallocateReservedPool (\r
  IN UINTN  OldSize,\r
  IN UINTN  NewSize,\r
  IN VOID   *OldBuffer  OPTIONAL\r
  )\r
{\r
  return InternalReallocatePool (EfiReservedMemoryType, OldSize, NewSize, OldBuffer);\r
}\r
\r
/**\r
  Frees a buffer that was previously allocated with one of the pool allocation functions in the\r
  Memory Allocation Library.\r
\r
  Frees the buffer specified by Buffer.  Buffer must have been allocated on a previous call to the\r
  pool allocation services of the Memory Allocation Library.  If it is not possible to free pool\r
  resources, then this function will perform no actions.\r
  \r
  If Buffer was not allocated with a pool allocation function in the Memory Allocation Library,\r
  then ASSERT().\r
\r
  @param  Buffer                Pointer to the buffer to free.\r
\r
**/\r
VOID\r
EFIAPI\r
FreePool (\r
  IN VOID   *Buffer\r
  )\r
{\r
  //\r
  // PEI phase does not support to free pool, so leave it as NOP.\r
  //\r
}\r
\r
\r