You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
279 lines
4.9 KiB
279 lines
4.9 KiB
/*++
|
|
|
|
Copyright (c) 1996 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
stubs.c
|
|
|
|
Abstract:
|
|
|
|
This module implements memory check routine for the boot debugger.
|
|
|
|
Author:
|
|
|
|
David N. Cutler (davec) 3-Dec-96
|
|
|
|
Environment:
|
|
|
|
Kernel mode only.
|
|
|
|
Revision History:
|
|
|
|
--*/
|
|
|
|
#include "bd.h"
|
|
|
|
extern BOOLEAN PaeEnabled;
|
|
|
|
|
|
|
|
BOOLEAN
|
|
BdCheckPdeValid (
|
|
IN PVOID Address
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine determines if the PDE for the specified address has the
|
|
valid bit set.
|
|
|
|
Agruments:
|
|
|
|
Address - Supplies the virtual address to check.
|
|
|
|
Return Value:
|
|
|
|
A value of TRUE indicates that the PDE for the supplied virtual address
|
|
does have the valid bit set, FALSE if it does not.
|
|
|
|
--*/
|
|
|
|
{
|
|
PHARDWARE_PTE_X86PAE PdePae;
|
|
PHARDWARE_PTE_X86 PdeX86;
|
|
|
|
if (PaeEnabled) {
|
|
|
|
//
|
|
// Physical address extenions are enabled.
|
|
//
|
|
|
|
PdePae = (PHARDWARE_PTE_X86PAE)PDE_BASE_X86PAE;
|
|
PdePae = &PdePae[ (ULONG)Address >> PDI_SHIFT_X86PAE ];
|
|
|
|
if (PdePae->Valid == 0) {
|
|
return FALSE;
|
|
} else {
|
|
return TRUE;
|
|
}
|
|
|
|
} else {
|
|
|
|
//
|
|
// Physical address extensions are not enabled.
|
|
//
|
|
|
|
PdeX86 = (PHARDWARE_PTE_X86)PDE_BASE;
|
|
PdeX86 = &PdeX86[ (ULONG)Address >> PDI_SHIFT_X86 ];
|
|
|
|
if (PdeX86->Valid == 0) {
|
|
return FALSE;
|
|
} else {
|
|
return TRUE;
|
|
}
|
|
}
|
|
}
|
|
|
|
BOOLEAN
|
|
BdCheckPteValid (
|
|
IN PVOID Address
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine determines if the PTE for the specified address has the
|
|
valid bit set.
|
|
|
|
Agruments:
|
|
|
|
Address - Supplies the virtual address to check.
|
|
|
|
Return Value:
|
|
|
|
A value of TRUE indicates that the PTE for the supplied virtual address
|
|
does have the valid bit set, FALSE if it does not.
|
|
|
|
--*/
|
|
|
|
{
|
|
PHARDWARE_PTE_X86PAE PtePae;
|
|
PHARDWARE_PTE_X86 PteX86;
|
|
|
|
if (PaeEnabled) {
|
|
|
|
//
|
|
// Physical address extenions are enabled.
|
|
//
|
|
|
|
PtePae = (PHARDWARE_PTE_X86PAE)PTE_BASE;
|
|
PtePae = &PtePae[ (ULONG)Address >> PTI_SHIFT ];
|
|
|
|
if (PtePae->Valid == 0) {
|
|
return FALSE;
|
|
} else {
|
|
return TRUE;
|
|
}
|
|
|
|
} else {
|
|
|
|
//
|
|
// Physical address extensions are not enabled.
|
|
//
|
|
|
|
PteX86 = (PHARDWARE_PTE_X86)PTE_BASE;
|
|
PteX86 = &PteX86[ (ULONG)Address >> PTI_SHIFT ];
|
|
|
|
if (PteX86->Valid == 0) {
|
|
return FALSE;
|
|
} else {
|
|
return TRUE;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
PVOID
|
|
BdReadCheck (
|
|
IN PVOID Address
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine determines if the specified address can be read.
|
|
|
|
Arguments:
|
|
|
|
Address - Supplies the virtual address to check.
|
|
|
|
Return Value:
|
|
|
|
A value of NULL is returned if the address is not valid or readable.
|
|
Otherwise, the physical address of the corresponding virtual address
|
|
is returned.
|
|
|
|
--*/
|
|
|
|
{
|
|
//
|
|
// Check if the page containing the specified address is valid.
|
|
//
|
|
// N.B. If the address is valid, it is readable.
|
|
//
|
|
|
|
if (BdCheckPdeValid( Address ) == FALSE) {
|
|
|
|
//
|
|
// The PDE is not valid.
|
|
//
|
|
|
|
return NULL;
|
|
}
|
|
|
|
if (BdCheckPteValid( Address ) == FALSE) {
|
|
|
|
//
|
|
// The PDE was valid but the PTE is not.
|
|
//
|
|
|
|
return NULL;
|
|
}
|
|
|
|
return Address;
|
|
}
|
|
|
|
PVOID
|
|
BdWriteCheck (
|
|
IN PVOID Address
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine determines if the specified address can be written.
|
|
|
|
Arguments:
|
|
|
|
Address - Supplies the virtual address to check.
|
|
|
|
Return Value:
|
|
|
|
A value of NULL is returned if the address is not valid or writeable.
|
|
Otherwise, the physical address of the corresponding virtual address
|
|
is returned.
|
|
|
|
--*/
|
|
|
|
{
|
|
//
|
|
// Check if the page containing the specified address is valid.
|
|
//
|
|
// N.B. If the address is valid, it is writeable since the WP bit
|
|
// is not set in cr0.
|
|
//
|
|
|
|
if (BdCheckPdeValid( Address ) == FALSE) {
|
|
|
|
//
|
|
// The PDE is not valid.
|
|
//
|
|
|
|
return NULL;
|
|
}
|
|
|
|
if (BdCheckPteValid( Address ) == FALSE) {
|
|
|
|
//
|
|
// The PDE was valid but the PTE is not.
|
|
//
|
|
|
|
return NULL;
|
|
}
|
|
|
|
return Address;
|
|
}
|
|
|
|
PVOID
|
|
BdTranslatePhysicalAddress (
|
|
IN PHYSICAL_ADDRESS Address
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine returns the phyiscal address for a physical address
|
|
which is valid (mapped).
|
|
|
|
Arguments:
|
|
|
|
Address - Supplies the physical address to check.
|
|
|
|
Return Value:
|
|
|
|
Returns NULL if the address is not valid or readable. Otherwise,
|
|
returns the physical address of the corresponding virtual address.
|
|
|
|
--*/
|
|
|
|
{
|
|
|
|
return (PVOID)Address.LowPart;
|
|
}
|