subsystems/win32/win32k/eng/mem.c

   1 /*
   2  *  ReactOS W32 Subsystem
   3  *  Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 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 along
  16  *  with this program; if not, write to the Free Software Foundation, Inc.,
  17  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19 /* $Id$
  20  *
  21  * COPYRIGHT:         See COPYING in the top level directory
  22  * PROJECT:           ReactOS kernel
  23  * PURPOSE:           GDI Driver Memory Management Functions
  24  * FILE:              subsys/win32k/eng/mem.c
  25  * PROGRAMER:         Jason Filby
  26  * REVISION HISTORY:
  27  *                 3/7/1999: Created
  28  */
  29
  30 #include <win32k.h>
  31
  32 #define NDEBUG
  33 #include <debug.h>
  34
  35 /*
  36  * @implemented
  37  */
  38 PVOID APIENTRY
  39 EngAllocMem(ULONG Flags,
  40             ULONG MemSize,
  41             ULONG Tag)
  42 {
  43   PVOID newMem;
  44
  45   newMem = ExAllocatePoolWithTag(PagedPool, MemSize, Tag);
  46
  47   if (Flags == FL_ZERO_MEMORY && NULL != newMem)
  48   {
  49     RtlZeroMemory(newMem, MemSize);
  50   }
  51
  52   return newMem;
  53 }
  54
  55 /*
  56  * @implemented
  57  */
  58 VOID APIENTRY
  59 EngFreeMem(PVOID Mem)
  60 {
  61   ExFreePool(Mem);
  62 }
  63
  64 /*
  65  * @implemented
  66  */
  67 PVOID APIENTRY
  68 EngAllocUserMem(SIZE_T cj, ULONG Tag)
  69 {
  70   PVOID NewMem = NULL;
  71   NTSTATUS Status;
  72   SIZE_T MemSize = cj;
  73
  74   Status = ZwAllocateVirtualMemory(NtCurrentProcess(), &NewMem, 0, &MemSize, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
  75
  76   if (! NT_SUCCESS(Status))
  77     {
  78       return NULL;
  79     }
  80
  81   /* TODO: Add allocation info to AVL tree (stored inside W32PROCESS structure) */
  82   //hSecure = EngSecureMem(NewMem, cj);
  83
  84   return NewMem;
  85 }
  86
  87 /*
  88  * @implemented
  89  */
  90 VOID APIENTRY
  91 EngFreeUserMem(PVOID pv)
  92 {
  93   PVOID BaseAddress = pv;
  94   SIZE_T MemSize = 0;
  95
  96   ZwFreeVirtualMemory(NtCurrentProcess(), &BaseAddress, &MemSize, MEM_RELEASE);
  97
  98   /* TODO: Remove allocation info from AVL tree */
  99 }
 100
 101
 102
 103 PVOID
 104 APIENTRY
 105 HackSecureVirtualMemory(
 106         IN PVOID Address,
 107         IN SIZE_T Size,
 108         IN ULONG ProbeMode,
 109         OUT PVOID *SafeAddress)
 110 {
 111         NTSTATUS Status = STATUS_SUCCESS;
 112         PMDL mdl;
 113         LOCK_OPERATION Operation;
 114
 115         if (ProbeMode == PAGE_READONLY) Operation = IoReadAccess;
 116         else if (ProbeMode == PAGE_READWRITE) Operation = IoModifyAccess;
 117         else return NULL;
 118
 119         mdl = IoAllocateMdl(Address, Size, FALSE, TRUE, NULL);
 120         if (mdl == NULL)
 121         {
 122                 return NULL;
 123         }
 124
 125         _SEH2_TRY
 126         {
 127                 MmProbeAndLockPages(mdl, UserMode, Operation);
 128         }
 129         _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
 130         {
 131                 Status = _SEH2_GetExceptionCode();
 132         }
 133         _SEH2_END
 134
 135         if (!NT_SUCCESS(Status))
 136         {
 137                 IoFreeMdl(mdl);
 138                 return NULL;
 139         }
 140
 141         *SafeAddress = MmGetSystemAddressForMdlSafe(mdl, NormalPagePriority);
 142
 143         if(!*SafeAddress)
 144         {
 145                 MmUnlockPages(mdl);
 146                 IoFreeMdl(mdl);
 147                 return NULL;
 148         }
 149
 150         return mdl;
 151 }
 152
 153 VOID
 154 APIENTRY
 155 HackUnsecureVirtualMemory(
 156         IN PVOID  SecureHandle)
 157 {
 158         PMDL mdl = (PMDL)SecureHandle;
 159
 160         MmUnlockPages(mdl);
 161         IoFreeMdl(mdl);
 162 }
 163
 164 /*
 165  * @implemented
 166  */
 167 HANDLE APIENTRY
 168 EngSecureMem(PVOID Address, ULONG Length)
 169 {
 170     return (HANDLE)-1; // HACK!!!
 171   return MmSecureVirtualMemory(Address, Length, PAGE_READWRITE);
 172 }
 173
 174 /*
 175  * @implemented
 176  */
 177 VOID APIENTRY
 178 EngUnsecureMem(HANDLE Mem)
 179 {
 180     if (Mem == (HANDLE)-1) return;  // HACK!!!
 181   MmUnsecureVirtualMemory((PVOID) Mem);
 182 }
 183
 184 /* EOF */