/** @file Support routines for memory allocation routines based on boot services for Dxe phase drivers. Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent **/ #include #include #include #include //#include /** Allocates one or more 4KB pages of a certain memory type. Allocates the number of 4KB pages of a certain memory type 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. @param MemoryType The type of memory to allocate. @param Pages The number of 4 KB pages to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalAllocatePages ( IN EFI_MEMORY_TYPE MemoryType, IN UINTN Pages ) { EFI_STATUS Status; EFI_PHYSICAL_ADDRESS Memory; if (Pages == 0) { return NULL; } Status = gBS->AllocatePages (AllocateAnyPages, MemoryType, Pages, &Memory); if (EFI_ERROR(Status)) { return NULL; } return (VOID *) (UINTN) Memory; } /** 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. @param Pages The number of 4 KB pages to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocatePages ( IN UINTN Pages ) { return InternalAllocatePages (EfiBootServicesData, 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. @param Pages The number of 4 KB pages to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateRuntimePages ( IN UINTN Pages ) { return InternalAllocatePages (EfiRuntimeServicesData, 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. @param Pages The number of 4 KB pages to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateReservedPages ( IN UINTN Pages ) { return InternalAllocatePages (EfiReservedMemoryType, 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(). @param Buffer The pointer to the buffer of pages to free. @param Pages The number of 4 KB pages to free. **/ VOID EFIAPI FreePages ( IN VOID *Buffer, IN UINTN Pages ) { EFI_STATUS Status; // ASSERT (Pages != 0); if (!Pages) { return; } Status = gBS->FreePages ((EFI_PHYSICAL_ADDRESS) (UINTN) Buffer, Pages); // ASSERT_EFI_ERROR(Status); if (EFI_ERROR(Status)) { return; } } /** Allocates one or more 4KB pages of a certain memory type at a specified alignment. Allocates the number of 4KB pages specified by Pages of a certain memory type 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(). @param MemoryType The type of memory to allocate. @param Pages The number of 4 KB pages to allocate. @param Alignment The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalAllocateAlignedPages ( IN EFI_MEMORY_TYPE MemoryType, IN UINTN Pages, IN UINTN Alignment ) { EFI_STATUS Status; EFI_PHYSICAL_ADDRESS Memory; UINTN AlignedMemory; UINTN AlignmentMask; UINTN UnalignedPages; UINTN RealPages; // // Alignment must be a power of two or zero. // // ASSERT ((Alignment & (Alignment - 1)) == 0); if ((Alignment & (Alignment - 1)) != 0) { return NULL; } if (Pages == 0) { return NULL; } if (Alignment > EFI_PAGE_SIZE) { // // Calculate the total number of pages since alignment is larger than page size. // AlignmentMask = Alignment - 1; RealPages = Pages + EFI_SIZE_TO_PAGES (Alignment); // // Make sure that Pages plus EFI_SIZE_TO_PAGES (Alignment) does not overflow. // // ASSERT (RealPages > Pages); if (RealPages < Pages) { return NULL; } Status = gBS->AllocatePages (AllocateAnyPages, MemoryType, RealPages, &Memory); if (EFI_ERROR(Status)) { return NULL; } AlignedMemory = ((UINTN) Memory + AlignmentMask) & ~AlignmentMask; UnalignedPages = EFI_SIZE_TO_PAGES (AlignedMemory - (UINTN) Memory); if (UnalignedPages > 0) { // // Free first unaligned page(s). // Status = gBS->FreePages (Memory, UnalignedPages); // ASSERT_EFI_ERROR(Status); if (EFI_ERROR(Status)) { return NULL; } } Memory = AlignedMemory + EFI_PAGES_TO_SIZE (Pages); UnalignedPages = RealPages - Pages - UnalignedPages; if (UnalignedPages > 0) { // // Free last unaligned page(s). // Status = gBS->FreePages (Memory, UnalignedPages); // ASSERT_EFI_ERROR(Status); if (EFI_ERROR(Status)) { return NULL; } } } else { // // Do not over-allocate pages in this case. // Status = gBS->AllocatePages (AllocateAnyPages, MemoryType, Pages, &Memory); if (EFI_ERROR(Status)) { return NULL; } AlignedMemory = (UINTN) Memory; } return (VOID *) AlignedMemory; } /** 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(). @param Pages The number of 4 KB pages to allocate. @param Alignment The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateAlignedPages ( IN UINTN Pages, IN UINTN Alignment ) { return InternalAllocateAlignedPages (EfiBootServicesData, Pages, 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(). @param Pages The number of 4 KB pages to allocate. @param Alignment The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateAlignedRuntimePages ( IN UINTN Pages, IN UINTN Alignment ) { return InternalAllocateAlignedPages (EfiRuntimeServicesData, Pages, 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(). @param Pages The number of 4 KB pages to allocate. @param Alignment The requested alignment of the allocation. Must be a power of two. If Alignment is zero, then byte alignment is used. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateAlignedReservedPages ( IN UINTN Pages, IN UINTN Alignment ) { return InternalAllocateAlignedPages (EfiReservedMemoryType, Pages, Alignment); } /** 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(). @param Buffer The pointer to the buffer of pages to free. @param Pages The number of 4 KB pages to free. **/ VOID EFIAPI FreeAlignedPages ( IN VOID *Buffer, IN UINTN Pages ) { // EFI_STATUS Status; // ASSERT (Pages != 0); if (!Pages || !Buffer) { return; } /* Status = */gBS->FreePages ((EFI_PHYSICAL_ADDRESS) (UINTN) Buffer, Pages); // ASSERT_EFI_ERROR(Status); } /** Allocates a buffer of a certain pool type. Allocates the number bytes specified by AllocationSize of a certain pool type 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. @param MemoryType The type of memory to allocate. @param AllocationSize The number of bytes to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalAllocatePool ( IN EFI_MEMORY_TYPE MemoryType, IN UINTN AllocationSize ) { EFI_STATUS Status; VOID *Memory = NULL; /* if (AllocationSize == 0) { return NULL; } */ Status = gBS->AllocatePool (MemoryType, AllocationSize, &Memory); if (EFI_ERROR(Status)) { Memory = NULL; } return Memory; } /** 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. @param AllocationSize The number of bytes to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocatePool ( IN UINTN AllocationSize ) { return InternalAllocatePool (EfiBootServicesData, 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. @param AllocationSize The number of bytes to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateRuntimePool ( IN UINTN AllocationSize ) { return InternalAllocatePool (EfiRuntimeServicesData, 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. @param AllocationSize The number of bytes to allocate. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateReservedPool ( IN UINTN AllocationSize ) { return InternalAllocatePool (EfiReservedMemoryType, AllocationSize); } /** Allocates and zeros a buffer of a certain pool type. Allocates the number bytes specified by AllocationSize of a certain pool type, 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. @param PoolType The type of memory to allocate. @param AllocationSize The number of bytes to allocate and zero. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalAllocateZeroPool( IN EFI_MEMORY_TYPE PoolType, IN UINTN AllocationSize ) { VOID *Memory; Memory = InternalAllocatePool (PoolType, AllocationSize); if (Memory != NULL) { Memory = ZeroMem (Memory, AllocationSize); } return Memory; } /** 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. @param AllocationSize The number of bytes to allocate and zero. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateZeroPool( IN UINTN AllocationSize ) { return InternalAllocateZeroPool(EfiBootServicesData, 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. @param AllocationSize The number of bytes to allocate and zero. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateRuntimeZeroPool ( IN UINTN AllocationSize ) { return InternalAllocateZeroPool(EfiRuntimeServicesData, 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. @param AllocationSize The number of bytes to allocate and zero. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateReservedZeroPool ( IN UINTN AllocationSize ) { return InternalAllocateZeroPool(EfiReservedMemoryType, AllocationSize); } /** Copies a buffer to an allocated buffer of a certain pool type. Allocates the number bytes specified by AllocationSize of a certain pool type, 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(). @param PoolType The type of pool to allocate. @param AllocationSize The number of bytes to allocate and zero. @param Buffer The buffer to copy to the allocated buffer. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalAllocateCopyPool( IN EFI_MEMORY_TYPE PoolType, IN UINTN AllocationSize, IN CONST VOID *Buffer ) { VOID *Memory; // ASSERT (Buffer != NULL); if (!Buffer) { return NULL; } // ASSERT (AllocationSize <= (MAX_ADDRESS - (UINTN) Buffer + 1)); if (AllocationSize > (MAX_ADDRESS - (UINTN) Buffer + 1)) { return NULL; } Memory = InternalAllocatePool (PoolType, AllocationSize); if (Memory != NULL) { Memory = CopyMem(Memory, Buffer, AllocationSize); } return Memory; } /** 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(). @param AllocationSize The number of bytes to allocate and zero. @param Buffer The buffer to copy to the allocated buffer. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateCopyPool( IN UINTN AllocationSize, IN CONST VOID *Buffer ) { return InternalAllocateCopyPool(EfiBootServicesData, AllocationSize, 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(). @param AllocationSize The number of bytes to allocate and zero. @param Buffer The buffer to copy to the allocated buffer. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateRuntimeCopyPool ( IN UINTN AllocationSize, IN CONST VOID *Buffer ) { return InternalAllocateCopyPool(EfiRuntimeServicesData, AllocationSize, 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(). @param AllocationSize The number of bytes to allocate and zero. @param Buffer The buffer to copy to the allocated buffer. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI AllocateReservedCopyPool ( IN UINTN AllocationSize, IN CONST VOID *Buffer ) { return InternalAllocateCopyPool(EfiReservedMemoryType, AllocationSize, Buffer); } /** Reallocates a buffer of a specified memory type. Allocates and zeros the number bytes specified by NewSize from memory of the type specified by PoolType. 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(). @param PoolType The type of pool to allocate. @param OldSize The size, in bytes, of OldBuffer. @param NewSize The size, in bytes, of the buffer to reallocate. @param OldBuffer The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * InternalReallocatePool ( IN EFI_MEMORY_TYPE PoolType, IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer OPTIONAL ) { VOID *NewBuffer; NewBuffer = InternalAllocateZeroPool(PoolType, NewSize); if (NewBuffer != NULL && OldBuffer != NULL) { CopyMem(NewBuffer, OldBuffer, MIN (OldSize, NewSize)); FreePool(OldBuffer); } return NewBuffer; } /** 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(). @param OldSize The size, in bytes, of OldBuffer. @param NewSize The size, in bytes, of the buffer to reallocate. @param OldBuffer The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI ReallocatePool ( IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer OPTIONAL ) { return InternalReallocatePool (EfiBootServicesData, OldSize, NewSize, 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(). @param OldSize The size, in bytes, of OldBuffer. @param NewSize The size, in bytes, of the buffer to reallocate. @param OldBuffer The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI ReallocateRuntimePool ( IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer OPTIONAL ) { return InternalReallocatePool (EfiRuntimeServicesData, OldSize, NewSize, 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(). @param OldSize The size, in bytes, of OldBuffer. @param NewSize The size, in bytes, of the buffer to reallocate. @param OldBuffer The buffer to copy to the allocated buffer. This is an optional parameter that may be NULL. @return A pointer to the allocated buffer or NULL if allocation fails. **/ VOID * EFIAPI ReallocateReservedPool ( IN UINTN OldSize, IN UINTN NewSize, IN VOID *OldBuffer OPTIONAL ) { return InternalReallocatePool (EfiReservedMemoryType, OldSize, NewSize, OldBuffer); } /** 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(). @param Buffer The pointer to the buffer to free. **/ VOID EFIAPI FreePool( IN VOID *Buffer ) { // EFI_STATUS Status; if (Buffer) { gBS->FreePool(Buffer); } // Status = gBS->FreePool(Buffer); // ASSERT_EFI_ERROR(Status); }