Functions
VOID *EFIAPI	AllocatePages (IN UINTN Pages)

VOID *EFIAPI	AllocateRuntimePages (IN UINTN Pages)

VOID *EFIAPI	AllocateReservedPages (IN UINTN Pages)

VOID EFIAPI	FreePages (IN VOID *Buffer, IN UINTN Pages)

VOID *EFIAPI	AllocateAlignedPages (IN UINTN Pages, IN UINTN Alignment)

VOID *EFIAPI	AllocateAlignedRuntimePages (IN UINTN Pages, IN UINTN Alignment)

VOID *EFIAPI	AllocateAlignedReservedPages (IN UINTN Pages, IN UINTN Alignment)

VOID EFIAPI	FreeAlignedPages (IN VOID *Buffer, IN UINTN Pages)

VOID *EFIAPI	AllocatePool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateRuntimePool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateReservedPool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateZeroPool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateRuntimeZeroPool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateReservedZeroPool (IN UINTN AllocationSize)

VOID *EFIAPI	AllocateCopyPool (IN UINTN AllocationSize, IN CONST VOID *Buffer)

VOID *EFIAPI	AllocateRuntimeCopyPool (IN UINTN AllocationSize, IN CONST VOID *Buffer)

VOID *EFIAPI	AllocateReservedCopyPool (IN UINTN AllocationSize, IN CONST VOID *Buffer)

VOID *EFIAPI	ReallocatePool (IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer)

VOID *EFIAPI	ReallocateRuntimePool (IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer)

VOID *EFIAPI	ReallocateReservedPool (IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer)

VOID EFIAPI	FreePool (IN VOID *Buffer)

Detailed Description

Provides services to allocate and free memory buffers of various memory types and alignments.

The Memory Allocation Library abstracts various common memory allocation operations. This library allows code to be written in a phase-independent manner because the allocation of memory in PEI, DXE, and SMM (for example) is done via a different mechanism. Using a common library interface makes it much easier to port algorithms from phase to phase.

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Function Documentation

VOID* EFIAPI AllocateAlignedPages	(	IN UINTN	Pages,
		IN UINTN	Alignment
	)

Allocates one or more 4KB pages of type EfiBootServicesData at a specified alignment.

Allocates the number of 4KB pages specified by Pages of type EfiBootServicesData with an alignment specified by Alignment. The allocated buffer is returned. If Pages is 0, then NULL is returned. If there is not enough memory at the specified alignment remaining to satisfy the request, then NULL is returned.

If Alignment is not a power of two and Alignment is not zero, then ASSERT(). If Pages plus EFI_SIZE_TO_PAGES (Alignment) overflows, then ASSERT().

Parameters

Pages	The number of 4 KB pages to allocate.
Alignment	The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateAlignedReservedPages	(	IN UINTN	Pages,
		IN UINTN	Alignment
	)

Allocates one or more 4KB pages of type EfiReservedMemoryType at a specified alignment.

Allocates the number of 4KB pages specified by Pages of type EfiReservedMemoryType with an alignment specified by Alignment. The allocated buffer is returned. If Pages is 0, then NULL is returned. If there is not enough memory at the specified alignment remaining to satisfy the request, then NULL is returned.

If Alignment is not a power of two and Alignment is not zero, then ASSERT(). If Pages plus EFI_SIZE_TO_PAGES (Alignment) overflows, then ASSERT().

Parameters

Pages	The number of 4 KB pages to allocate.
Alignment	The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateAlignedRuntimePages	(	IN UINTN	Pages,
		IN UINTN	Alignment
	)

Allocates one or more 4KB pages of type EfiRuntimeServicesData at a specified alignment.

Allocates the number of 4KB pages specified by Pages of type EfiRuntimeServicesData with an alignment specified by Alignment. The allocated buffer is returned. If Pages is 0, then NULL is returned. If there is not enough memory at the specified alignment remaining to satisfy the request, then NULL is returned.

If Alignment is not a power of two and Alignment is not zero, then ASSERT(). If Pages plus EFI_SIZE_TO_PAGES (Alignment) overflows, then ASSERT().

Parameters

Pages	The number of 4 KB pages to allocate.
Alignment	The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateCopyPool	(	IN UINTN	AllocationSize,
		IN CONST VOID *	Buffer
	)

Copies a buffer to an allocated buffer of type EfiBootServicesData.

Allocates the number bytes specified by AllocationSize of type EfiBootServicesData, copies AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If Buffer is NULL, then ASSERT(). If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

Parameters

AllocationSize	The number of bytes to allocate and zero.
Buffer	The buffer to copy to the allocated buffer.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocatePages ( IN UINTN Pages )

Allocates one or more 4KB pages of type EfiBootServicesData.

Allocates the number of 4KB pages of type EfiBootServicesData and returns a pointer to the allocated buffer. The buffer returned is aligned on a 4KB boundary. If Pages is 0, then NULL is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

Pages The number of 4 KB pages to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocatePool ( IN UINTN AllocationSize )

Allocates a buffer of type EfiBootServicesData.

Allocates the number bytes specified by AllocationSize of type EfiBootServicesData and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateReservedCopyPool	(	IN UINTN	AllocationSize,
		IN CONST VOID *	Buffer
	)

Copies a buffer to an allocated buffer of type EfiReservedMemoryType.

Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType, copies AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If Buffer is NULL, then ASSERT(). If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

Parameters

AllocationSize	The number of bytes to allocate and zero.
Buffer	The buffer to copy to the allocated buffer.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateReservedPages ( IN UINTN Pages )

Allocates one or more 4KB pages of type EfiReservedMemoryType.

Allocates the number of 4KB pages of type EfiReservedMemoryType and returns a pointer to the allocated buffer. The buffer returned is aligned on a 4KB boundary. If Pages is 0, then NULL is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

Pages The number of 4 KB pages to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateReservedPool ( IN UINTN AllocationSize )

Allocates a buffer of type EfiReservedMemoryType.

Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateReservedZeroPool ( IN UINTN AllocationSize )

Allocates and zeros a buffer of type EfiReservedMemoryType.

Allocates the number bytes specified by AllocationSize of type EfiReservedMemoryType, clears the buffer with zeros, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate and zero.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateRuntimeCopyPool	(	IN UINTN	AllocationSize,
		IN CONST VOID *	Buffer
	)

Copies a buffer to an allocated buffer of type EfiRuntimeServicesData.

Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData, copies AllocationSize bytes from Buffer to the newly allocated buffer, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If Buffer is NULL, then ASSERT(). If AllocationSize is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

Parameters

AllocationSize	The number of bytes to allocate and zero.
Buffer	The buffer to copy to the allocated buffer.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateRuntimePages ( IN UINTN Pages )

Allocates one or more 4KB pages of type EfiRuntimeServicesData.

Allocates the number of 4KB pages of type EfiRuntimeServicesData and returns a pointer to the allocated buffer. The buffer returned is aligned on a 4KB boundary. If Pages is 0, then NULL is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

Pages The number of 4 KB pages to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateRuntimePool ( IN UINTN AllocationSize )

Allocates a buffer of type EfiRuntimeServicesData.

Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateRuntimeZeroPool ( IN UINTN AllocationSize )

Allocates and zeros a buffer of type EfiRuntimeServicesData.

Allocates the number bytes specified by AllocationSize of type EfiRuntimeServicesData, clears the buffer with zeros, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate and zero.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI AllocateZeroPool ( IN UINTN AllocationSize )

Allocates and zeros a buffer of type EfiBootServicesData.

Allocates the number bytes specified by AllocationSize of type EfiBootServicesData, clears the buffer with zeros, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

Parameters

AllocationSize The number of bytes to allocate and zero.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID EFIAPI FreeAlignedPages	(	IN VOID *	Buffer,
		IN UINTN	Pages
	)

Frees one or more 4KB pages that were previously allocated with one of the aligned page allocation functions in the Memory Allocation Library.

Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer. Buffer must have been allocated on a previous call to the aligned page allocation services of the Memory Allocation Library. If it is not possible to free allocated pages, then this function will perform no actions.

If Buffer was not allocated with an aligned page allocation function in the Memory Allocation Library, then ASSERT(). If Pages is zero, then ASSERT().

Parameters

Buffer	Pointer to the buffer of pages to free.
Pages	The number of 4 KB pages to free.

VOID EFIAPI FreePages	(	IN VOID *	Buffer,
		IN UINTN	Pages
	)

Frees one or more 4KB pages that were previously allocated with one of the page allocation functions in the Memory Allocation Library.

Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer. Buffer must have been allocated on a previous call to the page allocation services of the Memory Allocation Library. If it is not possible to free allocated pages, then this function will perform no actions.

If Buffer was not allocated with a page allocation function in the Memory Allocation Library, then ASSERT(). If Pages is zero, then ASSERT().

Parameters

Buffer	Pointer to the buffer of pages to free.
Pages	The number of 4 KB pages to free.

VOID EFIAPI FreePool ( IN VOID * Buffer )

Frees a buffer that was previously allocated with one of the pool allocation functions in the Memory Allocation Library.

Frees the buffer specified by Buffer. Buffer must have been allocated on a previous call to the pool allocation services of the Memory Allocation Library. If it is not possible to free pool resources, then this function will perform no actions.

If Buffer was not allocated with a pool allocation function in the Memory Allocation Library, then ASSERT().

Parameters

Buffer Pointer to the buffer to free.

VOID* EFIAPI ReallocatePool	(	IN UINTN	OldSize,
		IN UINTN	NewSize,
		IN VOID *	OldBuffer
	)

Reallocates a buffer of type EfiBootServicesData.

Allocates and zeros the number bytes specified by NewSize from memory of type EfiBootServicesData. If OldBuffer is not NULL, then the smaller of OldSize and NewSize bytes are copied from OldBuffer to the newly allocated buffer, and OldBuffer is freed. A pointer to the newly allocated buffer is returned. If NewSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If the allocation of the new buffer is successful and the smaller of NewSize and OldSize is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().

Parameters

OldSize	The size, in bytes, of OldBuffer.
NewSize	The size, in bytes, of the buffer to reallocate.
OldBuffer	The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI ReallocateReservedPool	(	IN UINTN	OldSize,
		IN UINTN	NewSize,
		IN VOID *	OldBuffer
	)

Reallocates a buffer of type EfiReservedMemoryType.

Allocates and zeros the number bytes specified by NewSize from memory of type EfiReservedMemoryType. If OldBuffer is not NULL, then the smaller of OldSize and NewSize bytes are copied from OldBuffer to the newly allocated buffer, and OldBuffer is freed. A pointer to the newly allocated buffer is returned. If NewSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If the allocation of the new buffer is successful and the smaller of NewSize and OldSize is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().

Parameters

OldSize	The size, in bytes, of OldBuffer.
NewSize	The size, in bytes, of the buffer to reallocate.
OldBuffer	The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

VOID* EFIAPI ReallocateRuntimePool	(	IN UINTN	OldSize,
		IN UINTN	NewSize,
		IN VOID *	OldBuffer
	)

Reallocates a buffer of type EfiRuntimeServicesData.

Allocates and zeros the number bytes specified by NewSize from memory of type EfiRuntimeServicesData. If OldBuffer is not NULL, then the smaller of OldSize and NewSize bytes are copied from OldBuffer to the newly allocated buffer, and OldBuffer is freed. A pointer to the newly allocated buffer is returned. If NewSize is 0, then a valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.

If the allocation of the new buffer is successful and the smaller of NewSize and OldSize is greater than (MAX_ADDRESS - OldBuffer + 1), then ASSERT().

Parameters

OldSize	The size, in bytes, of OldBuffer.
NewSize	The size, in bytes, of the buffer to reallocate.
OldBuffer	The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL.

Returns: A pointer to the allocated buffer or NULL if allocation fails.

Functions

Detailed Description

Function Documentation