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.
173 lines
3.6 KiB
173 lines
3.6 KiB
title "I386 PCR"
|
|
;++
|
|
;
|
|
; Copyright (c) 1989 Microsoft Corporation
|
|
;
|
|
; Module Name:
|
|
;
|
|
; i386pcr.asm
|
|
;
|
|
; Abstract:
|
|
;
|
|
; This module implements routines for accessing and initing the pcr.
|
|
;
|
|
; Author:
|
|
;
|
|
; Bryan Willman (bryanwi) 20 Mar 90
|
|
;
|
|
; Environment:
|
|
;
|
|
; Kernel mode, early init of first processor.
|
|
;
|
|
; Revision History:
|
|
;
|
|
;--
|
|
|
|
.386p
|
|
.xlist
|
|
include ks386.inc
|
|
include callconv.inc ; calling convention macros
|
|
.list
|
|
|
|
;
|
|
; NOTE - This definition of PCR gives us 2 instructions to get to some
|
|
; variables that need to be addressable in one instruction. Any
|
|
; such variable (such as current thread) must be accessed via its
|
|
; own access procedure (see below), NOT by KeGetPcr()->PbCurrentThread.
|
|
; (This is only an issue on MP machines.)
|
|
;
|
|
|
|
_TEXT$00 SEGMENT DWORD PUBLIC 'CODE'
|
|
ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING
|
|
|
|
;++
|
|
;
|
|
; PKTHREAD
|
|
; KeGetCurrentThread()
|
|
;
|
|
; Return Value:
|
|
;
|
|
; Pointer to current Thread object.
|
|
;
|
|
;--
|
|
cPublicProc ___KeGetCurrentThread ,0
|
|
|
|
mov eax,PCR[PcPrcbData+PbCurrentThread]
|
|
stdRET ___KeGetCurrentThread
|
|
|
|
stdENDP ___KeGetCurrentThread
|
|
|
|
|
|
;++
|
|
;
|
|
; KPROCESSOR_MODE
|
|
; KeGetPreviousMode()
|
|
;
|
|
; Return Value:
|
|
;
|
|
; PreviousMode of current thread.
|
|
;
|
|
;--
|
|
cPublicProc _KeGetPreviousMode
|
|
|
|
mov eax,PCR[PcPrcbData+PbCurrentThread] ; (eax) -> Thread
|
|
movzx eax,byte ptr [eax]+ThPreviousMode ; (eax) = PreviousMode
|
|
stdRET _KeGetPreviousMode
|
|
|
|
stdENDP _KeGetPreviousMode
|
|
|
|
|
|
;++
|
|
;
|
|
; BOOLEAN
|
|
; KeIsExecutingDpc(
|
|
; VOID
|
|
; );
|
|
;
|
|
; Return Value:
|
|
;
|
|
; Value of flag which indicates whether we're executing in DPC context
|
|
;
|
|
;--
|
|
|
|
cPublicProc ___KeIsExecutingDpc ,0
|
|
|
|
movzx eax, byte ptr PCR[PcPrcbData.PbDpcRoutineActive]
|
|
stdRET ___KeIsExecutingDpc
|
|
|
|
stdENDP ___KeIsExecutingDpc
|
|
|
|
|
|
;++
|
|
;
|
|
; VOID
|
|
; GetMachineBootPointers(
|
|
; )
|
|
;
|
|
; Routine Description:
|
|
;
|
|
; This routine is called at system startup to extract the address of
|
|
; the PCR and machine control values. It is useful only for the P0
|
|
; case where the boot loader must already init the machine before it
|
|
; turns on paging and calls us.
|
|
;
|
|
; Pcr address is extracted from the base of KGDT_R0_PCR.
|
|
;
|
|
; Gdt and Idt are extracted from the machine GDTR and IDTR.
|
|
;
|
|
; TSS is derived from the TSR and related descriptor.
|
|
;
|
|
; Arguments:
|
|
;
|
|
; None.
|
|
;
|
|
; Return Value:
|
|
;
|
|
;
|
|
; (edi) -> gdt
|
|
; (esi) -> pcr
|
|
; (edx) -> tss
|
|
; (eax) -> idt
|
|
;
|
|
;--
|
|
|
|
cPublicProc GetMachineBootPointers
|
|
|
|
push ebp
|
|
mov ebp,esp
|
|
sub esp,8
|
|
|
|
sgdt fword ptr [ebp-8]
|
|
mov edi,[ebp-6] ; (edi) = gdt address
|
|
|
|
mov cx,fs
|
|
and cx,(NOT RPL_MASK)
|
|
movzx ecx,cx
|
|
add ecx,edi ; (ecx) -> pcr descriptor
|
|
|
|
mov dh,[ecx+KgdtBaseHi]
|
|
mov dl,[ecx+KgdtBaseMid]
|
|
shl edx,16
|
|
mov dx,[ecx+KgdtBaseLow] ; (edx) -> pcr
|
|
mov esi,edx ; (esi) -> pcr
|
|
|
|
str cx
|
|
movzx ecx,cx
|
|
add ecx,edi ; (ecx) -> TSS descriptor
|
|
|
|
mov dh,[ecx+KgdtBaseHi]
|
|
mov dl,[ecx+KgdtBaseMid]
|
|
shl edx,16
|
|
mov dx,[ecx+KgdtBaseLow] ; (edx) -> TSS
|
|
|
|
sidt fword ptr [ebp-8]
|
|
mov eax,[ebp-6] ; (eax) -> Idt
|
|
|
|
mov esp,ebp
|
|
pop ebp
|
|
stdRET GetMachineBootPointers
|
|
|
|
stdENDP GetMachineBootPointers
|
|
|
|
_TEXT$00 ENDS
|
|
end
|