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system76-edk2/UefiCpuPkg/CpuDxe/CpuPageTable.c
Jeff Fan c69a51ce65 UefiCpuPkg: Error Level is not used correctly 
Cc: Feng Tian <feng.tian@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
2017-04-12 09:00:37 +08:00

789 lines
26 KiB
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/** @file
Page table management support.
Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include <Base.h>
#include <Uefi.h>
#include <Library/BaseLib.h>
#include <Library/CpuLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Protocol/MpService.h>
#include "CpuPageTable.h"
///
/// Page Table Entry
///
#define IA32_PG_P BIT0
#define IA32_PG_RW BIT1
#define IA32_PG_U BIT2
#define IA32_PG_WT BIT3
#define IA32_PG_CD BIT4
#define IA32_PG_A BIT5
#define IA32_PG_D BIT6
#define IA32_PG_PS BIT7
#define IA32_PG_PAT_2M BIT12
#define IA32_PG_PAT_4K IA32_PG_PS
#define IA32_PG_PMNT BIT62
#define IA32_PG_NX BIT63
#define PAGE_ATTRIBUTE_BITS (IA32_PG_D | IA32_PG_A | IA32_PG_U | IA32_PG_RW | IA32_PG_P)
//
// Bits 1, 2, 5, 6 are reserved in the IA32 PAE PDPTE
// X64 PAE PDPTE does not have such restriction
//
#define IA32_PAE_PDPTE_ATTRIBUTE_BITS (IA32_PG_P)
#define PAGE_PROGATE_BITS (IA32_PG_NX | PAGE_ATTRIBUTE_BITS)
#define PAGING_4K_MASK 0xFFF
#define PAGING_2M_MASK 0x1FFFFF
#define PAGING_1G_MASK 0x3FFFFFFF
#define PAGING_PAE_INDEX_MASK 0x1FF
#define PAGING_4K_ADDRESS_MASK_64 0x000FFFFFFFFFF000ull
#define PAGING_2M_ADDRESS_MASK_64 0x000FFFFFFFE00000ull
#define PAGING_1G_ADDRESS_MASK_64 0x000FFFFFC0000000ull
typedef enum {
PageNone,
Page4K,
Page2M,
Page1G,
} PAGE_ATTRIBUTE;
typedef struct {
PAGE_ATTRIBUTE Attribute;
UINT64 Length;
UINT64 AddressMask;
} PAGE_ATTRIBUTE_TABLE;
typedef enum {
PageActionAssign,
PageActionSet,
PageActionClear,
} PAGE_ACTION;
PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
{Page4K, SIZE_4KB, PAGING_4K_ADDRESS_MASK_64},
{Page2M, SIZE_2MB, PAGING_2M_ADDRESS_MASK_64},
{Page1G, SIZE_1GB, PAGING_1G_ADDRESS_MASK_64},
};
/**
Enable write protection function for AP.
@param[in,out] Buffer The pointer to private data buffer.
**/
VOID
EFIAPI
SyncCpuEnableWriteProtection (
IN OUT VOID *Buffer
)
{
AsmWriteCr0 (AsmReadCr0 () | BIT16);
}
/**
CpuFlushTlb function for AP.
@param[in,out] Buffer The pointer to private data buffer.
**/
VOID
EFIAPI
SyncCpuFlushTlb (
IN OUT VOID *Buffer
)
{
CpuFlushTlb();
}
/**
Sync memory page attributes for AP.
@param[in] Procedure A pointer to the function to be run on enabled APs of
the system.
**/
VOID
SyncMemoryPageAttributesAp (
IN EFI_AP_PROCEDURE Procedure
)
{
EFI_STATUS Status;
EFI_MP_SERVICES_PROTOCOL *MpService;
Status = gBS->LocateProtocol (
&gEfiMpServiceProtocolGuid,
NULL,
(VOID **)&MpService
);
//
// Synchronize the update with all APs
//
if (!EFI_ERROR (Status)) {
Status = MpService->StartupAllAPs (
MpService, // This
Procedure, // Procedure
FALSE, // SingleThread
NULL, // WaitEvent
0, // TimeoutInMicrosecsond
NULL, // ProcedureArgument
NULL // FailedCpuList
);
ASSERT (Status == EFI_SUCCESS || Status == EFI_NOT_STARTED || Status == EFI_NOT_READY);
}
}
/**
Return current paging context.
@param[in,out] PagingContext The paging context.
**/
VOID
GetCurrentPagingContext (
IN OUT PAGE_TABLE_LIB_PAGING_CONTEXT *PagingContext
)
{
UINT32 RegEax;
UINT32 RegEdx;
ZeroMem(PagingContext, sizeof(*PagingContext));
if (sizeof(UINTN) == sizeof(UINT64)) {
PagingContext->MachineType = IMAGE_FILE_MACHINE_X64;
} else {
PagingContext->MachineType = IMAGE_FILE_MACHINE_I386;
}
if ((AsmReadCr0 () & BIT31) != 0) {
PagingContext->ContextData.X64.PageTableBase = (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
if ((AsmReadCr0 () & BIT16) == 0) {
AsmWriteCr0 (AsmReadCr0 () | BIT16);
SyncMemoryPageAttributesAp (SyncCpuEnableWriteProtection);
}
} else {
PagingContext->ContextData.X64.PageTableBase = 0;
}
if ((AsmReadCr4 () & BIT4) != 0) {
PagingContext->ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PSE;
}
if ((AsmReadCr4 () & BIT5) != 0) {
PagingContext->ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE;
}
if ((AsmReadCr0 () & BIT16) != 0) {
PagingContext->ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_WP_ENABLE;
}
AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
if (RegEax > 0x80000000) {
AsmCpuid (0x80000001, NULL, NULL, NULL, &RegEdx);
if ((RegEdx & BIT20) != 0) {
// XD supported
if ((AsmReadMsr64 (0xC0000080) & BIT11) != 0) {
// XD activated
PagingContext->ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_XD_ACTIVATED;
}
}
if ((RegEdx & BIT26) != 0) {
PagingContext->ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAGE_1G_SUPPORT;
}
}
}
/**
Return length according to page attributes.
@param[in] PageAttributes The page attribute of the page entry.
@return The length of page entry.
**/
UINTN
PageAttributeToLength (
IN PAGE_ATTRIBUTE PageAttribute
)
{
UINTN Index;
for (Index = 0; Index < sizeof(mPageAttributeTable)/sizeof(mPageAttributeTable[0]); Index++) {
if (PageAttribute == mPageAttributeTable[Index].Attribute) {
return (UINTN)mPageAttributeTable[Index].Length;
}
}
return 0;
}
/**
Return address mask according to page attributes.
@param[in] PageAttributes The page attribute of the page entry.
@return The address mask of page entry.
**/
UINTN
PageAttributeToMask (
IN PAGE_ATTRIBUTE PageAttribute
)
{
UINTN Index;
for (Index = 0; Index < sizeof(mPageAttributeTable)/sizeof(mPageAttributeTable[0]); Index++) {
if (PageAttribute == mPageAttributeTable[Index].Attribute) {
return (UINTN)mPageAttributeTable[Index].AddressMask;
}
}
return 0;
}
/**
Return page table entry to match the address.
@param[in] PagingContext The paging context.
@param[in] Address The address to be checked.
@param[out] PageAttributes The page attribute of the page entry.
@return The page entry.
**/
VOID *
GetPageTableEntry (
IN PAGE_TABLE_LIB_PAGING_CONTEXT *PagingContext,
IN PHYSICAL_ADDRESS Address,
OUT PAGE_ATTRIBUTE *PageAttribute
)
{
UINTN Index1;
UINTN Index2;
UINTN Index3;
UINTN Index4;
UINT64 *L1PageTable;
UINT64 *L2PageTable;
UINT64 *L3PageTable;
UINT64 *L4PageTable;
UINT64 AddressEncMask;
ASSERT (PagingContext != NULL);
Index4 = ((UINTN)RShiftU64 (Address, 39)) & PAGING_PAE_INDEX_MASK;
Index3 = ((UINTN)Address >> 30) & PAGING_PAE_INDEX_MASK;
Index2 = ((UINTN)Address >> 21) & PAGING_PAE_INDEX_MASK;
Index1 = ((UINTN)Address >> 12) & PAGING_PAE_INDEX_MASK;
// Make sure AddressEncMask is contained to smallest supported address field.
//
AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
if (PagingContext->MachineType == IMAGE_FILE_MACHINE_X64) {
L4PageTable = (UINT64 *)(UINTN)PagingContext->ContextData.X64.PageTableBase;
if (L4PageTable[Index4] == 0) {
*PageAttribute = PageNone;
return NULL;
}
L3PageTable = (UINT64 *)(UINTN)(L4PageTable[Index4] & ~AddressEncMask & PAGING_4K_ADDRESS_MASK_64);
} else {
ASSERT((PagingContext->ContextData.Ia32.Attributes & PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE) != 0);
L3PageTable = (UINT64 *)(UINTN)PagingContext->ContextData.Ia32.PageTableBase;
}
if (L3PageTable[Index3] == 0) {
*PageAttribute = PageNone;
return NULL;
}
if ((L3PageTable[Index3] & IA32_PG_PS) != 0) {
// 1G
*PageAttribute = Page1G;
return &L3PageTable[Index3];
}
L2PageTable = (UINT64 *)(UINTN)(L3PageTable[Index3] & ~AddressEncMask & PAGING_4K_ADDRESS_MASK_64);
if (L2PageTable[Index2] == 0) {
*PageAttribute = PageNone;
return NULL;
}
if ((L2PageTable[Index2] & IA32_PG_PS) != 0) {
// 2M
*PageAttribute = Page2M;
return &L2PageTable[Index2];
}
// 4k
L1PageTable = (UINT64 *)(UINTN)(L2PageTable[Index2] & ~AddressEncMask & PAGING_4K_ADDRESS_MASK_64);
if ((L1PageTable[Index1] == 0) && (Address != 0)) {
*PageAttribute = PageNone;
return NULL;
}
*PageAttribute = Page4K;
return &L1PageTable[Index1];
}
/**
Return memory attributes of page entry.
@param[in] PageEntry The page entry.
@return Memory attributes of page entry.
**/
UINT64
GetAttributesFromPageEntry (
IN UINT64 *PageEntry
)
{
UINT64 Attributes;
Attributes = 0;
if ((*PageEntry & IA32_PG_P) == 0) {
Attributes |= EFI_MEMORY_RP;
}
if ((*PageEntry & IA32_PG_RW) == 0) {
Attributes |= EFI_MEMORY_RO;
}
if ((*PageEntry & IA32_PG_NX) != 0) {
Attributes |= EFI_MEMORY_XP;
}
return Attributes;
}
/**
Modify memory attributes of page entry.
@param[in] PagingContext The paging context.
@param[in] PageEntry The page entry.
@param[in] Attributes The bit mask of attributes to modify for the memory region.
@param[in] PageAction The page action.
@param[out] IsModified TRUE means page table modified. FALSE means page table not modified.
**/
VOID
ConvertPageEntryAttribute (
IN PAGE_TABLE_LIB_PAGING_CONTEXT *PagingContext,
IN UINT64 *PageEntry,
IN UINT64 Attributes,
IN PAGE_ACTION PageAction,
OUT BOOLEAN *IsModified
)
{
UINT64 CurrentPageEntry;
UINT64 NewPageEntry;
CurrentPageEntry = *PageEntry;
NewPageEntry = CurrentPageEntry;
if ((Attributes & EFI_MEMORY_RP) != 0) {
switch (PageAction) {
case PageActionAssign:
case PageActionSet:
NewPageEntry &= ~(UINT64)IA32_PG_P;
break;
case PageActionClear:
NewPageEntry |= IA32_PG_P;
break;
}
} else {
switch (PageAction) {
case PageActionAssign:
NewPageEntry |= IA32_PG_P;
break;
case PageActionSet:
case PageActionClear:
break;
}
}
if ((Attributes & EFI_MEMORY_RO) != 0) {
switch (PageAction) {
case PageActionAssign:
case PageActionSet:
NewPageEntry &= ~(UINT64)IA32_PG_RW;
break;
case PageActionClear:
NewPageEntry |= IA32_PG_RW;
break;
}
} else {
switch (PageAction) {
case PageActionAssign:
NewPageEntry |= IA32_PG_RW;
break;
case PageActionSet:
case PageActionClear:
break;
}
}
if ((PagingContext->ContextData.Ia32.Attributes & PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_XD_ACTIVATED) != 0) {
if ((Attributes & EFI_MEMORY_XP) != 0) {
switch (PageAction) {
case PageActionAssign:
case PageActionSet:
NewPageEntry |= IA32_PG_NX;
break;
case PageActionClear:
NewPageEntry &= ~IA32_PG_NX;
break;
}
} else {
switch (PageAction) {
case PageActionAssign:
NewPageEntry &= ~IA32_PG_NX;
break;
case PageActionSet:
case PageActionClear:
break;
}
}
}
*PageEntry = NewPageEntry;
if (CurrentPageEntry != NewPageEntry) {
*IsModified = TRUE;
DEBUG ((DEBUG_INFO, "ConvertPageEntryAttribute 0x%lx", CurrentPageEntry));
DEBUG ((DEBUG_INFO, "->0x%lx\n", NewPageEntry));
} else {
*IsModified = FALSE;
}
}
/**
This function returns if there is need to split page entry.
@param[in] BaseAddress The base address to be checked.
@param[in] Length The length to be checked.
@param[in] PageEntry The page entry to be checked.
@param[in] PageAttribute The page attribute of the page entry.
@retval SplitAttributes on if there is need to split page entry.
**/
PAGE_ATTRIBUTE
NeedSplitPage (
IN PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 *PageEntry,
IN PAGE_ATTRIBUTE PageAttribute
)
{
UINT64 PageEntryLength;
PageEntryLength = PageAttributeToLength (PageAttribute);
if (((BaseAddress & (PageEntryLength - 1)) == 0) && (Length >= PageEntryLength)) {
return PageNone;
}
if (((BaseAddress & PAGING_2M_MASK) != 0) || (Length < SIZE_2MB)) {
return Page4K;
}
return Page2M;
}
/**
This function splits one page entry to small page entries.
@param[in] PageEntry The page entry to be splitted.
@param[in] PageAttribute The page attribute of the page entry.
@param[in] SplitAttribute How to split the page entry.
@param[in] AllocatePagesFunc If page split is needed, this function is used to allocate more pages.
@retval RETURN_SUCCESS The page entry is splitted.
@retval RETURN_UNSUPPORTED The page entry does not support to be splitted.
@retval RETURN_OUT_OF_RESOURCES No resource to split page entry.
**/
RETURN_STATUS
SplitPage (
IN UINT64 *PageEntry,
IN PAGE_ATTRIBUTE PageAttribute,
IN PAGE_ATTRIBUTE SplitAttribute,
IN PAGE_TABLE_LIB_ALLOCATE_PAGES AllocatePagesFunc
)
{
UINT64 BaseAddress;
UINT64 *NewPageEntry;
UINTN Index;
UINT64 AddressEncMask;
ASSERT (PageAttribute == Page2M || PageAttribute == Page1G);
ASSERT (AllocatePagesFunc != NULL);
// Make sure AddressEncMask is contained to smallest supported address field.
//
AddressEncMask = PcdGet64 (PcdPteMemoryEncryptionAddressOrMask) & PAGING_1G_ADDRESS_MASK_64;
if (PageAttribute == Page2M) {
//
// Split 2M to 4K
//
ASSERT (SplitAttribute == Page4K);
if (SplitAttribute == Page4K) {
NewPageEntry = AllocatePagesFunc (1);
DEBUG ((DEBUG_INFO, "Split - 0x%x\n", NewPageEntry));
if (NewPageEntry == NULL) {
return RETURN_OUT_OF_RESOURCES;
}
BaseAddress = *PageEntry & ~AddressEncMask & PAGING_2M_ADDRESS_MASK_64;
for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
NewPageEntry[Index] = (BaseAddress + SIZE_4KB * Index) | AddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
}
(*PageEntry) = (UINT64)(UINTN)NewPageEntry | AddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
return RETURN_SUCCESS;
} else {
return RETURN_UNSUPPORTED;
}
} else if (PageAttribute == Page1G) {
//
// Split 1G to 2M
// No need support 1G->4K directly, we should use 1G->2M, then 2M->4K to get more compact page table.
//
ASSERT (SplitAttribute == Page2M || SplitAttribute == Page4K);
if ((SplitAttribute == Page2M || SplitAttribute == Page4K)) {
NewPageEntry = AllocatePagesFunc (1);
DEBUG ((DEBUG_INFO, "Split - 0x%x\n", NewPageEntry));
if (NewPageEntry == NULL) {
return RETURN_OUT_OF_RESOURCES;
}
BaseAddress = *PageEntry & ~AddressEncMask & PAGING_1G_ADDRESS_MASK_64;
for (Index = 0; Index < SIZE_4KB / sizeof(UINT64); Index++) {
NewPageEntry[Index] = (BaseAddress + SIZE_2MB * Index) | AddressEncMask | IA32_PG_PS | ((*PageEntry) & PAGE_PROGATE_BITS);
}
(*PageEntry) = (UINT64)(UINTN)NewPageEntry | AddressEncMask | ((*PageEntry) & PAGE_PROGATE_BITS);
return RETURN_SUCCESS;
} else {
return RETURN_UNSUPPORTED;
}
} else {
return RETURN_UNSUPPORTED;
}
}
/**
This function modifies the page attributes for the memory region specified by BaseAddress and
Length from their current attributes to the attributes specified by Attributes.
Caller should make sure BaseAddress and Length is at page boundary.
@param[in] PagingContext The paging context. NULL means get page table from current CPU context.
@param[in] BaseAddress The physical address that is the start address of a memory region.
@param[in] Length The size in bytes of the memory region.
@param[in] Attributes The bit mask of attributes to modify for the memory region.
@param[in] PageAction The page action.
@param[in] AllocatePagesFunc If page split is needed, this function is used to allocate more pages.
NULL mean page split is unsupported.
@param[out] IsSplitted TRUE means page table splitted. FALSE means page table not splitted.
@param[out] IsModified TRUE means page table modified. FALSE means page table not modified.
@retval RETURN_SUCCESS The attributes were modified for the memory region.
@retval RETURN_ACCESS_DENIED The attributes for the memory resource range specified by
BaseAddress and Length cannot be modified.
@retval RETURN_INVALID_PARAMETER Length is zero.
Attributes specified an illegal combination of attributes that
cannot be set together.
@retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of
the memory resource range.
@retval RETURN_UNSUPPORTED The processor does not support one or more bytes of the memory
resource range specified by BaseAddress and Length.
The bit mask of attributes is not support for the memory resource
range specified by BaseAddress and Length.
**/
RETURN_STATUS
ConvertMemoryPageAttributes (
IN PAGE_TABLE_LIB_PAGING_CONTEXT *PagingContext OPTIONAL,
IN PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
IN PAGE_ACTION PageAction,
IN PAGE_TABLE_LIB_ALLOCATE_PAGES AllocatePagesFunc OPTIONAL,
OUT BOOLEAN *IsSplitted, OPTIONAL
OUT BOOLEAN *IsModified OPTIONAL
)
{
PAGE_TABLE_LIB_PAGING_CONTEXT CurrentPagingContext;
UINT64 *PageEntry;
PAGE_ATTRIBUTE PageAttribute;
UINTN PageEntryLength;
PAGE_ATTRIBUTE SplitAttribute;
RETURN_STATUS Status;
BOOLEAN IsEntryModified;
if ((BaseAddress & (SIZE_4KB - 1)) != 0) {
DEBUG ((DEBUG_ERROR, "BaseAddress(0x%lx) is not aligned!\n", BaseAddress));
return EFI_UNSUPPORTED;
}
if ((Length & (SIZE_4KB - 1)) != 0) {
DEBUG ((DEBUG_ERROR, "Length(0x%lx) is not aligned!\n", Length));
return EFI_UNSUPPORTED;
}
if (Length == 0) {
DEBUG ((DEBUG_ERROR, "Length is 0!\n"));
return RETURN_INVALID_PARAMETER;
}
if ((Attributes & ~(EFI_MEMORY_RP | EFI_MEMORY_RO | EFI_MEMORY_XP)) != 0) {
DEBUG ((DEBUG_ERROR, "Attributes(0x%lx) has unsupported bit\n", Attributes));
return EFI_UNSUPPORTED;
}
if (PagingContext == NULL) {
GetCurrentPagingContext (&CurrentPagingContext);
} else {
CopyMem (&CurrentPagingContext, PagingContext, sizeof(CurrentPagingContext));
}
switch(CurrentPagingContext.MachineType) {
case IMAGE_FILE_MACHINE_I386:
if (CurrentPagingContext.ContextData.Ia32.PageTableBase == 0) {
if (Attributes == 0) {
return EFI_SUCCESS;
} else {
DEBUG ((DEBUG_ERROR, "PageTable is 0!\n"));
return EFI_UNSUPPORTED;
}
}
if ((CurrentPagingContext.ContextData.Ia32.Attributes & PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE) == 0) {
DEBUG ((DEBUG_ERROR, "Non-PAE Paging!\n"));
return EFI_UNSUPPORTED;
}
break;
case IMAGE_FILE_MACHINE_X64:
ASSERT (CurrentPagingContext.ContextData.X64.PageTableBase != 0);
break;
default:
ASSERT(FALSE);
return EFI_UNSUPPORTED;
break;
}
// DEBUG ((DEBUG_ERROR, "ConvertMemoryPageAttributes(%x) - %016lx, %016lx, %02lx\n", IsSet, BaseAddress, Length, Attributes));
if (IsSplitted != NULL) {
*IsSplitted = FALSE;
}
if (IsModified != NULL) {
*IsModified = FALSE;
}
//
// Below logic is to check 2M/4K page to make sure we donot waist memory.
//
while (Length != 0) {
PageEntry = GetPageTableEntry (&CurrentPagingContext, BaseAddress, &PageAttribute);
if (PageEntry == NULL) {
return RETURN_UNSUPPORTED;
}
PageEntryLength = PageAttributeToLength (PageAttribute);
SplitAttribute = NeedSplitPage (BaseAddress, Length, PageEntry, PageAttribute);
if (SplitAttribute == PageNone) {
ConvertPageEntryAttribute (&CurrentPagingContext, PageEntry, Attributes, PageAction, &IsEntryModified);
if (IsEntryModified) {
if (IsModified != NULL) {
*IsModified = TRUE;
}
}
//
// Convert success, move to next
//
BaseAddress += PageEntryLength;
Length -= PageEntryLength;
} else {
if (AllocatePagesFunc == NULL) {
return RETURN_UNSUPPORTED;
}
Status = SplitPage (PageEntry, PageAttribute, SplitAttribute, AllocatePagesFunc);
if (RETURN_ERROR (Status)) {
return RETURN_UNSUPPORTED;
}
if (IsSplitted != NULL) {
*IsSplitted = TRUE;
}
if (IsModified != NULL) {
*IsModified = TRUE;
}
//
// Just split current page
// Convert success in next around
//
}
}
return RETURN_SUCCESS;
}
/**
This function assigns the page attributes for the memory region specified by BaseAddress and
Length from their current attributes to the attributes specified by Attributes.
Caller should make sure BaseAddress and Length is at page boundary.
Caller need guarentee the TPL <= TPL_NOTIFY, if there is split page request.
@param[in] PagingContext The paging context. NULL means get page table from current CPU context.
@param[in] BaseAddress The physical address that is the start address of a memory region.
@param[in] Length The size in bytes of the memory region.
@param[in] Attributes The bit mask of attributes to set for the memory region.
@param[in] AllocatePagesFunc If page split is needed, this function is used to allocate more pages.
NULL mean page split is unsupported.
@retval RETURN_SUCCESS The attributes were cleared for the memory region.
@retval RETURN_ACCESS_DENIED The attributes for the memory resource range specified by
BaseAddress and Length cannot be modified.
@retval RETURN_INVALID_PARAMETER Length is zero.
Attributes specified an illegal combination of attributes that
cannot be set together.
@retval RETURN_OUT_OF_RESOURCES There are not enough system resources to modify the attributes of
the memory resource range.
@retval RETURN_UNSUPPORTED The processor does not support one or more bytes of the memory
resource range specified by BaseAddress and Length.
The bit mask of attributes is not support for the memory resource
range specified by BaseAddress and Length.
**/
RETURN_STATUS
EFIAPI
AssignMemoryPageAttributes (
IN PAGE_TABLE_LIB_PAGING_CONTEXT *PagingContext OPTIONAL,
IN PHYSICAL_ADDRESS BaseAddress,
IN UINT64 Length,
IN UINT64 Attributes,
IN PAGE_TABLE_LIB_ALLOCATE_PAGES AllocatePagesFunc OPTIONAL
)
{
RETURN_STATUS Status;
BOOLEAN IsModified;
BOOLEAN IsSplitted;
// DEBUG((DEBUG_INFO, "AssignMemoryPageAttributes: 0x%lx - 0x%lx (0x%lx)\n", BaseAddress, Length, Attributes));
Status = ConvertMemoryPageAttributes (PagingContext, BaseAddress, Length, Attributes, PageActionAssign, AllocatePagesFunc, &IsSplitted, &IsModified);
if (!EFI_ERROR(Status)) {
if ((PagingContext == NULL) && IsModified) {
//
// Flush TLB as last step
//
CpuFlushTlb();
SyncMemoryPageAttributesAp (SyncCpuFlushTlb);
}
}
return Status;
}
/**
Initialize the Page Table lib.
**/
VOID
InitializePageTableLib (
VOID
)
{
PAGE_TABLE_LIB_PAGING_CONTEXT CurrentPagingContext;
GetCurrentPagingContext (&CurrentPagingContext);
DEBUG ((DEBUG_INFO, "CurrentPagingContext:\n", CurrentPagingContext.MachineType));
DEBUG ((DEBUG_INFO, " MachineType - 0x%x\n", CurrentPagingContext.MachineType));
DEBUG ((DEBUG_INFO, " PageTableBase - 0x%x\n", CurrentPagingContext.ContextData.X64.PageTableBase));
DEBUG ((DEBUG_INFO, " Attributes - 0x%x\n", CurrentPagingContext.ContextData.X64.Attributes));
return ;
}
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