PageTbl.c File Reference

#include "PiSmmCpuCommon.h"

Go to the source code of this file.

Macros
#define	PAGE_TABLE_PAGES   8
#define	ACC_MAX_BIT   BIT3

Functions
BOOLEAN	Is1GPageSupport (VOID)
BOOLEAN	Is5LevelPagingNeeded (VOID)
VOID	SetSubEntriesNum (IN OUT UINT64 *Entry, IN UINT64 SubEntryNum)
UINT64	GetSubEntriesNum (IN UINT64 *Entry)
UINT8	CalculateMaximumSupportAddress (BOOLEAN Is5LevelPagingNeeded)
UINT32	SmmInitPageTable (VOID)
VOID	SetAccNum (IN OUT UINT64 *Entry, IN UINT64 Acc)
UINT64	GetAccNum (IN UINT64 *Entry)
UINT64	GetAndUpdateAccNum (IN OUT UINT64 *Entry)
VOID	ReclaimPages (VOID)
UINT64	AllocPage (VOID)
VOID EFIAPI	SmiPFHandler (IN EFI_EXCEPTION_TYPE InterruptType, IN EFI_SYSTEM_CONTEXT SystemContext)
VOID	SaveCr2 (OUT UINTN *Cr2)
VOID	RestoreCr2 (IN UINTN Cr2)

Variables
LIST_ENTRY	mPagePool = INITIALIZE_LIST_HEAD_VARIABLE (mPagePool)
BOOLEAN	m1GPageTableSupport = FALSE
X86_ASSEMBLY_PATCH_LABEL	gPatch5LevelPagingNeeded

Detailed Description

Page Fault (#PF) handler for X64 processors

Copyright (c) 2009 - 2024, Intel Corporation. All rights reserved.
Copyright (c) 2017, AMD Incorporated. All rights reserved.

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

Definition in file PageTbl.c.

Macro Definition Documentation

ACC_MAX_BIT

#define ACC_MAX_BIT   BIT3

Definition at line 14 of file PageTbl.c.

PAGE_TABLE_PAGES

#define PAGE_TABLE_PAGES   8

Definition at line 13 of file PageTbl.c.

Function Documentation

AllocPage()

UINT64 AllocPage

(

VOID

)

Allocate free Page for PageFault handler use.

Returns

Page address.

Definition at line 688 of file PageTbl.c.

CalculateMaximumSupportAddress()

UINT8 CalculateMaximumSupportAddress

(

BOOLEAN

Is5LevelPagingNeeded

)

Calculate the maximum support address.

Parameters

[in]

Is5LevelPagingNeeded

If 5-level paging enabling is needed.

Returns

the maximum support address.

Definition at line 144 of file PageTbl.c.

GetAccNum()

UINT64 GetAccNum

(

IN UINT64 *

Entry

)

Return access record in entry.

Parameters

[in]

Entry

Pointer to entry

Returns

Access record value.

Definition at line 353 of file PageTbl.c.

GetAndUpdateAccNum()

UINT64 GetAndUpdateAccNum

(

IN OUT UINT64 *

Entry

)

Return and update the access record in entry.

Parameters

[in,out]

Entry

Pointer to entry

Returns

Access record value.

Definition at line 372 of file PageTbl.c.

GetSubEntriesNum()

UINT64 GetSubEntriesNum

(

IN UINT64 *

Entry

)

Return sub-entries number in entry.

Parameters

[in]

Entry

Pointer to entry

Returns

Sub-entries number based on 0: 0 means there is 1 sub-entry under this entry 0x1ff means there is 512 sub-entries under this entry

Definition at line 126 of file PageTbl.c.

Is1GPageSupport()

BOOLEAN Is1GPageSupport

(

VOID

)

Check if 1-GByte pages is supported by processor or not.

Return values

TRUE	1-GByte pages is supported.
FALSE	1-GByte pages is not supported.

Definition at line 28 of file PageTbl.c.

Is5LevelPagingNeeded()

BOOLEAN Is5LevelPagingNeeded

(

VOID

)

The routine returns TRUE when CPU supports it (CPUID[7,0].ECX.BIT[16] is set) and the max physical address bits is bigger than 48. Because 4-level paging can support to address physical address up to 2^48 - 1, there is no need to enable 5-level paging with max physical address bits <= 48.

Return values

TRUE	5-level paging enabling is needed.
FALSE	5-level paging enabling is not needed.

Definition at line 56 of file PageTbl.c.

ReclaimPages()

VOID ReclaimPages

(

VOID

)

Reclaim free pages for PageFault handler.

Search the whole entries tree to find the leaf entry that has the smallest access record value. Insert the page pointed by this leaf entry into the page pool. And check its upper entries if need to be inserted into the page pool or not.

Definition at line 409 of file PageTbl.c.

RestoreCr2()

VOID RestoreCr2

(

IN UINTN

Cr2

)

This function restores CR2 register.

Parameters

[in]

Cr2

Value to write into CR2 register.

Definition at line 884 of file PageTbl.c.

SaveCr2()

VOID SaveCr2

(

OUT UINTN *

Cr2

)

This function reads CR2 register.

Parameters

[out]

*Cr2

Pointer to variable to hold CR2 register value.

Definition at line 863 of file PageTbl.c.

SetAccNum()

VOID SetAccNum	(	IN OUT UINT64 *	Entry,
		IN UINT64	Acc
	)

Set access record in entry.

Parameters

[in,out]	Entry	Pointer to entry
[in]	Acc	Access record value

Definition at line 333 of file PageTbl.c.

SetSubEntriesNum()

VOID SetSubEntriesNum	(	IN OUT UINT64 *	Entry,
		IN UINT64	SubEntryNum
	)

Set sub-entries number in entry.

Parameters

[in,out]	Entry	Pointer to entry
[in]	SubEntryNum	Sub-entries number based on 0: 0 means there is 1 sub-entry under this entry 0x1ff means there is 512 sub-entries under this entry

Definition at line 105 of file PageTbl.c.

SmiPFHandler()

VOID EFIAPI SmiPFHandler	(	IN EFI_EXCEPTION_TYPE	InterruptType,
		IN EFI_SYSTEM_CONTEXT	SystemContext
	)

ThePage Fault handler wrapper for SMM use.

Parameters

InterruptType	Defines the type of interrupt or exception that occurred on the processor.This parameter is processor architecture specific.
SystemContext	A pointer to the processor context when the interrupt occurred on the processor.

Definition at line 723 of file PageTbl.c.

SmmInitPageTable()

UINT32 SmmInitPageTable

(

VOID

)

Create PageTable for SMM use.

Returns

The address of PML4 (to set CR3). Zero if any error occurs.

Definition at line 191 of file PageTbl.c.

Variable Documentation

gPatch5LevelPagingNeeded

X86_ASSEMBLY_PATCH_LABEL gPatch5LevelPagingNeeded

Definition at line 18 of file PageTbl.c.

m1GPageTableSupport

BOOLEAN m1GPageTableSupport = FALSE

Definition at line 17 of file PageTbl.c.

mPagePool

LIST_ENTRY mPagePool = INITIALIZE_LIST_HEAD_VARIABLE (mPagePool)

Definition at line 16 of file PageTbl.c.