CpuPaging.c File Reference

#include <Register/Intel/Cpuid.h>
#include <Register/Intel/Msr.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/CpuLib.h>
#include <Library/BaseLib.h>
#include <Guid/MigratedFvInfo.h>
#include "CpuMpPei.h"

Go to the source code of this file.

Macros
#define	PAGING_4K_ADDRESS_MASK_64   0x000FFFFFFFFFF000ull

Functions
BOOLEAN	IsIa32PaeSupported (VOID)
VOID *	AllocatePageTableMemory (IN UINTN Pages)
RETURN_STATUS	ConvertMemoryPageToNotPresent (IN PHYSICAL_ADDRESS BaseAddress, IN UINT64 Length)
EFI_STATUS	EnablePaePageTable (VOID)
VOID EFIAPI	GetStackBase (IN OUT VOID *Buffer)
VOID	SetupStackGuardPage (VOID)
EFI_STATUS EFIAPI	MemoryDiscoveredPpiNotifyCallback (IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_NOTIFY_DESCRIPTOR *NotifyDescriptor, IN VOID *Ppi)

Variables
EFI_PEI_NOTIFY_DESCRIPTOR	mPostMemNotifyList []

Detailed Description

Basic paging support for the CPU to enable Stack Guard.

Copyright (c) 2018 - 2019, Intel Corporation. All rights reserved.

SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file CpuPaging.c.

Macro Definition Documentation

PAGING_4K_ADDRESS_MASK_64

#define PAGING_4K_ADDRESS_MASK_64   0x000FFFFFFFFFF000ull

Definition at line 18 of file CpuPaging.c.

Function Documentation

AllocatePageTableMemory()

VOID * AllocatePageTableMemory

(

IN UINTN

Pages

)

This API provides a way to allocate memory for page table.

Parameters

Pages

The number of 4 KB pages to allocate.

Returns

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

Definition at line 63 of file CpuPaging.c.

ConvertMemoryPageToNotPresent()

RETURN_STATUS ConvertMemoryPageToNotPresent	(	IN PHYSICAL_ADDRESS	BaseAddress,
		IN UINT64	Length
	)

This function modifies the page attributes for the memory region specified by BaseAddress and Length to not present. This function only change page table, but not flush TLB. Caller have the responsbility to flush TLB.

Caller should make sure BaseAddress and Length is at page boundary.

Parameters

[in]	BaseAddress	Start address of a memory region.
[in]	Length	Size in bytes of the memory region.

Return values

RETURN_SUCCESS	The memory region is changed to not present.
RETURN_OUT_OF_RESOURCES	There are not enough system resources to modify the attributes.
RETURN_UNSUPPORTED	Cannot modify the attributes of given memory.

Definition at line 94 of file CpuPaging.c.

EnablePaePageTable()

EFI_STATUS EnablePaePageTable

(

VOID

)

Enable PAE Page Table.

Return values

EFI_SUCCESS	The PAE Page Table was enabled successfully.
EFI_OUT_OF_RESOURCES	The PAE Page Table could not be enabled due to lack of available memory.

Definition at line 182 of file CpuPaging.c.

GetStackBase()

VOID EFIAPI GetStackBase

(

IN OUT VOID *

Buffer

)

Get the base address of current AP's stack.

This function is called in AP's context and assumes that whole calling stacks (till this function) consumed by AP's wakeup procedure will not exceed 4KB.

PcdCpuApStackSize must be configured with value taking the Guard page into account.

Parameters

[in,out]

Buffer

The pointer to private data buffer.

Definition at line 265 of file CpuPaging.c.

IsIa32PaeSupported()

BOOLEAN IsIa32PaeSupported

(

VOID

)

The function will check if IA32 PAE is supported.

Return values

TRUE	IA32 PAE is supported.
FALSE	IA32 PAE is not supported.

Definition at line 36 of file CpuPaging.c.

MemoryDiscoveredPpiNotifyCallback()

EFI_STATUS EFIAPI MemoryDiscoveredPpiNotifyCallback	(	IN EFI_PEI_SERVICES **	PeiServices,
		IN EFI_PEI_NOTIFY_DESCRIPTOR *	NotifyDescriptor,
		IN VOID *	Ppi
	)

Enable/setup stack guard for each processor if PcdCpuStackGuard is set to TRUE.

Doing this in the memory-discovered callback is to make sure the Stack Guard feature to cover as most PEI code as possible.

Parameters

[in]	PeiServices	General purpose services available to every PEIM.
[in]	NotifyDescriptor	The notification structure this PEIM registered on install.
[in]	Ppi	The memory discovered PPI. Not used.

Return values

EFI_SUCCESS	The function completed successfully.
others	There's error in MP initialization.

Definition at line 372 of file CpuPaging.c.

SetupStackGuardPage()

VOID SetupStackGuardPage

(

VOID

)

Setup stack Guard page at the stack base of each processor. BSP and APs have different way to get stack base address.

Definition at line 287 of file CpuPaging.c.

Variable Documentation

mPostMemNotifyList

EFI_PEI_NOTIFY_DESCRIPTOR mPostMemNotifyList[]

Initial value:

= {
  {
    (EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
    &gEfiPeiMemoryDiscoveredPpiGuid,
    MemoryDiscoveredPpiNotifyCallback
  }
}

Definition at line 20 of file CpuPaging.c.