reactos/ntoskrnl/ke/process.c

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 1998, 1999, 2000, 2001 ReactOS Team
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19 /* $Id: process.c,v 1.8 2001/04/16 02:02:04 dwelch Exp $
  20  *
  21  * PROJECT:         ReactOS kernel
  22  * FILE:            ntoskrnl/ke/process.c
  23  * PURPOSE:         Microkernel process management
  24  * PROGRAMMER:      David Welch (welch@cwcom.net)
  25  * PORTABILITY:     No.
  26  * UPDATE HISTORY:
  27  *                  Created 22/05/98
  28  */
  29
  30 /* INCLUDES *****************************************************************/
  31
  32 #include <ddk/ntddk.h>
  33 #include <internal/ke.h>
  34 #include <internal/mm.h>
  35 #include <internal/ps.h>
  36
  37 #define NDEBUG
  38 #include <internal/debug.h>
  39
  40 /* FUNCTIONS *****************************************************************/
  41
  42 VOID STDCALL
  43 KeAttachProcess (PEPROCESS Process)
  44 {
  45    KIRQL oldlvl;
  46    PETHREAD CurrentThread;
  47    ULONG PageDir;
  48
  49    DPRINT("KeAttachProcess(Process %x)\n",Process);
  50
  51    CurrentThread = PsGetCurrentThread();
  52
  53    if (CurrentThread->OldProcess != NULL)
  54      {
  55         DbgPrint("Invalid attach (thread is already attached)\n");
  56         KeBugCheck(0);
  57      }
  58
  59    KeRaiseIrql(DISPATCH_LEVEL, &oldlvl);
  60
  61    CurrentThread->OldProcess = PsGetCurrentProcess();
  62    CurrentThread->ThreadsProcess = Process;
  63    PageDir = (ULONG)CurrentThread->ThreadsProcess->Pcb.DirectoryTableBase[0];
  64    DPRINT("Switching process context to %x\n",PageDir)
  65    __asm__("movl %0,%%cr3\n\t"
  66            : /* no inputs */
  67            : "r" (PageDir));
  68
  69
  70    KeLowerIrql(oldlvl);
  71 }
  72
  73 VOID STDCALL
  74 KeDetachProcess (VOID)
  75 {
  76    KIRQL oldlvl;
  77    PETHREAD CurrentThread;
  78    ULONG PageDir;
  79
  80    DPRINT("KeDetachProcess()\n");
  81
  82    CurrentThread = PsGetCurrentThread();
  83
  84    if (CurrentThread->OldProcess == NULL)
  85      {
  86         DbgPrint("Invalid detach (thread was not attached)\n");
  87         KeBugCheck(0);
  88      }
  89
  90    KeRaiseIrql(DISPATCH_LEVEL, &oldlvl);
  91
  92    CurrentThread->ThreadsProcess = CurrentThread->OldProcess;
  93    CurrentThread->OldProcess = NULL;
  94    PageDir = (ULONG)CurrentThread->ThreadsProcess->Pcb.DirectoryTableBase[0];
  95    __asm__("movl %0,%%cr3\n\t"
  96            : /* no inputs */
  97            : "r" (PageDir));
  98
  99    KeLowerIrql(oldlvl);
 100 }
 101
 102 /* EOF */