reactos/ntoskrnl/kd/i386/kdmemsup.c
Hermès Bélusca-Maïto aff644a1a2
[NTOS:KD][KDBG] Get rid of kdmemsup.c as its functionality has been superseded by that implemented in mm/arm3/mmdbg.c.
- Import KdpCopyMemoryChunks() from kd64/kdapi.c, and re-implement
  KdbpSafeReadMemory() and KdbpSafeWriteMemory() around it.
  Note that these functions read virtual memory and are equivalent of
  the kd64 KdpReadVirtualMemory() and KdpWriteVirtualMemory()
  respectively.

- Get rid of the KdpEnableSafeMem() call in KdInitSystem().
- Adjust kd gdbstub.c wrapper in accordance.
2019-11-03 23:46:52 +01:00

226 lines
5.3 KiB
C

/*****************************************************************************\
* *
* This file is current kept ONLY for DOCUMENTATION purposes, until *
* we are sure that all the functionality (e.g. regarding the "big pages") *
* are fully present in Mm and in mm/ARM3/mmdbg.c that supersedes this file. *
* *
\*****************************************************************************/
/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS Kernel
* FILE: ntoskrnl/kd/i386/kdmemsup.c
* PURPOSE: Kernel Debugger Safe Memory Support
*
* PROGRAMMERS: arty
*/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
#define HIGH_PHYS_MASK 0x80000000
#define PAGE_TABLE_MASK 0x3ff
#define BIG_PAGE_SIZE (1<<22)
#define CR4_PAGE_SIZE_BIT 0x10
#define PDE_PRESENT_BIT 0x01
#define PDE_W_BIT 0x02
#define PDE_PWT_BIT 0x08
#define PDE_PCD_BIT 0x10
#define PDE_ACCESSED_BIT 0x20
#define PDE_DIRTY_BIT 0x40
#define PDE_PS_BIT 0x80
#define MI_KDBG_TMP_PAGE_1 (HYPER_SPACE + 0x400000 - PAGE_SIZE)
#define MI_KDBG_TMP_PAGE_0 (MI_KDBG_TMP_PAGE_1 - PAGE_SIZE)
/* VARIABLES ***************************************************************/
static BOOLEAN KdpPhysAccess = FALSE;
static
ULONG_PTR
KdpPhysMap(ULONG_PTR PhysAddr, LONG Len)
{
MMPTE TempPte;
PMMPTE PointerPte;
ULONG_PTR VirtAddr;
TempPte.u.Long = PDE_PRESENT_BIT | PDE_W_BIT | PDE_PWT_BIT |
PDE_PCD_BIT | PDE_ACCESSED_BIT | PDE_DIRTY_BIT;
if ((PhysAddr & (PAGE_SIZE - 1)) + Len > PAGE_SIZE)
{
TempPte.u.Hard.PageFrameNumber = (PhysAddr >> PAGE_SHIFT) + 1;
PointerPte = MiAddressToPte((PVOID)MI_KDBG_TMP_PAGE_1);
*PointerPte = TempPte;
VirtAddr = (ULONG_PTR)PointerPte << 10;
KeInvalidateTlbEntry((PVOID)VirtAddr);
}
TempPte.u.Hard.PageFrameNumber = PhysAddr >> PAGE_SHIFT;
PointerPte = MiAddressToPte((PVOID)MI_KDBG_TMP_PAGE_0);
*PointerPte = TempPte;
VirtAddr = (ULONG_PTR)PointerPte << 10;
KeInvalidateTlbEntry((PVOID)VirtAddr);
return VirtAddr + (PhysAddr & (PAGE_SIZE - 1));
}
static
ULONGLONG
KdpPhysRead(ULONG_PTR PhysAddr, LONG Len)
{
ULONG_PTR Addr;
ULONGLONG Result = 0;
Addr = KdpPhysMap(PhysAddr, Len);
switch (Len)
{
case 8:
Result = *((PULONGLONG)Addr);
break;
case 4:
Result = *((PULONG)Addr);
break;
case 2:
Result = *((PUSHORT)Addr);
break;
case 1:
Result = *((PUCHAR)Addr);
break;
}
return Result;
}
static
VOID
KdpPhysWrite(ULONG_PTR PhysAddr, LONG Len, ULONGLONG Value)
{
ULONG_PTR Addr;
Addr = KdpPhysMap(PhysAddr, Len);
switch (Len)
{
case 8:
*((PULONGLONG)Addr) = Value;
break;
case 4:
*((PULONG)Addr) = Value;
break;
case 2:
*((PUSHORT)Addr) = Value;
break;
case 1:
*((PUCHAR)Addr) = Value;
break;
}
}
static
BOOLEAN
KdpTranslateAddress(ULONG_PTR Addr, PULONG_PTR ResultAddr)
{
ULONG_PTR CR3Value = __readcr3();
ULONG_PTR CR4Value = __readcr4();
ULONG_PTR PageDirectory = (CR3Value & ~(PAGE_SIZE-1)) +
((Addr >> 22) * sizeof(ULONG));
ULONG_PTR PageDirectoryEntry = KdpPhysRead(PageDirectory, sizeof(ULONG));
/* Not present -> fail */
if (!(PageDirectoryEntry & PDE_PRESENT_BIT))
{
return FALSE;
}
/* Big Page? */
if ((PageDirectoryEntry & PDE_PS_BIT) && (CR4Value & CR4_PAGE_SIZE_BIT))
{
*ResultAddr = (PageDirectoryEntry & ~(BIG_PAGE_SIZE-1)) +
(Addr & (BIG_PAGE_SIZE-1));
return TRUE;
}
else
{
ULONG_PTR PageTableAddr =
(PageDirectoryEntry & ~(PAGE_SIZE-1)) +
((Addr >> PAGE_SHIFT) & PAGE_TABLE_MASK) * sizeof(ULONG);
ULONG_PTR PageTableEntry = KdpPhysRead(PageTableAddr, sizeof(ULONG));
if (PageTableEntry & PDE_PRESENT_BIT)
{
*ResultAddr = (PageTableEntry & ~(PAGE_SIZE-1)) +
(Addr & (PAGE_SIZE-1));
return TRUE;
}
}
return FALSE;
}
BOOLEAN
NTAPI
KdpSafeReadMemory(ULONG_PTR Addr, LONG Len, PVOID Value)
{
ULONG_PTR ResultPhysAddr;
if (!KdpPhysAccess)
{
memcpy(Value, (PVOID)Addr, Len);
return TRUE;
}
memset(Value, 0, Len);
if (!KdpTranslateAddress(Addr, &ResultPhysAddr))
return FALSE;
switch (Len)
{
case 8:
*((PULONGLONG)Value) = KdpPhysRead(ResultPhysAddr, Len);
break;
case 4:
*((PULONG)Value) = KdpPhysRead(ResultPhysAddr, Len);
break;
case 2:
*((PUSHORT)Value) = KdpPhysRead(ResultPhysAddr, Len);
break;
case 1:
*((PUCHAR)Value) = KdpPhysRead(ResultPhysAddr, Len);
break;
}
return TRUE;
}
BOOLEAN
NTAPI
KdpSafeWriteMemory(ULONG_PTR Addr, LONG Len, ULONGLONG Value)
{
ULONG_PTR ResultPhysAddr;
if (!KdpPhysAccess)
{
memcpy((PVOID)Addr, &Value, Len);
return TRUE;
}
if (!KdpTranslateAddress(Addr, &ResultPhysAddr))
return FALSE;
KdpPhysWrite(ResultPhysAddr, Len, Value);
return TRUE;
}
VOID
NTAPI
KdpEnableSafeMem(VOID)
{
KdpPhysAccess = TRUE;
}
/* EOF */