ntoskrnl/mm/ncache.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/mm/cont.c
   6  * PURPOSE:         Manages non-cached memory
   7  * PROGRAMMER:      David Welch (welch@cwcom.net)
   8  * UPDATE HISTORY:
   9  *                  Created 22/05/98
  10  */
  11
  12 /* INCLUDES *****************************************************************/
  13
  14 #include <ddk/ntddk.h>
  15 #include <internal/mm.h>
  16 #include <internal/ps.h>
  17
  18 #define NDEBUG
  19 #include <internal/debug.h>
  20
  21 /* FUNCTIONS *****************************************************************/
  22
  23
  24 /**********************************************************************
  25  * NAME                                                 EXPORTED
  26  *      MmAllocateNonCachedMemory@4
  27  *
  28  * DESCRIPTION
  29  *      Allocates a virtual address range of noncached and cache
  30  *      aligned memory.
  31  *
  32  * ARGUMENTS
  33  *      NumberOfBytes
  34  *              Size of region to allocate.
  35  *
  36  * RETURN VALUE
  37  *      The base address of the range on success;
  38  *      NULL on failure.
  39  *
  40  * NOTE
  41  *      Description taken from include/ddk/mmfuncs.h.
  42  *      Code taken from ntoskrnl/mm/special.c.
  43  *
  44  * REVISIONS
  45  *
  46  */
  47 PVOID STDCALL
  48 MmAllocateNonCachedMemory(IN ULONG NumberOfBytes)
  49 {
  50    PVOID Result;
  51    MEMORY_AREA* marea;
  52    NTSTATUS Status;
  53    ULONG i;
  54    ULONG Attributes;
  55
  56    MmLockAddressSpace(MmGetKernelAddressSpace());
  57    Result = NULL;
  58    Status = MmCreateMemoryArea (NULL,
  59                                 MmGetKernelAddressSpace(),
  60                                 MEMORY_AREA_NO_CACHE,
  61                                 &Result,
  62                                 NumberOfBytes,
  63                                 0,
  64                                 &marea,
  65                                 FALSE);
  66    MmUnlockAddressSpace(MmGetKernelAddressSpace());
  67
  68    if (!NT_SUCCESS(Status))
  69      {
  70         return (NULL);
  71      }
  72    Attributes = PAGE_READWRITE | PAGE_SYSTEM | PAGE_NOCACHE |
  73      PAGE_WRITETHROUGH;
  74    for (i = 0; i <= (NumberOfBytes / PAGE_SIZE); i++)
  75      {
  76        PHYSICAL_ADDRESS NPage;
  77
  78        Status = MmRequestPageMemoryConsumer(MC_NPPOOL, TRUE, &NPage);
  79        MmCreateVirtualMapping (NULL,
  80                                Result + (i * PAGE_SIZE),
  81                                Attributes,
  82                                NPage,
  83                                TRUE);
  84      }
  85    return ((PVOID)Result);
  86 }
  87
  88 VOID STATIC
  89 MmFreeNonCachedPage(PVOID Context, MEMORY_AREA* MemoryArea, PVOID Address,
  90                     PHYSICAL_ADDRESS PhysAddr, SWAPENTRY SwapEntry,
  91                     BOOLEAN Dirty)
  92 {
  93   assert(SwapEntry == 0);
  94   if (PhysAddr.QuadPart != 0)
  95     {
  96       MmReleasePageMemoryConsumer(MC_NPPOOL, PhysAddr);
  97     }
  98 }
  99
 100 /**********************************************************************
 101  * NAME                                                 EXPORTED
 102  *      MmFreeNonCachedMemory@8
 103  *
 104  * DESCRIPTION
 105  *      Releases a range of noncached memory allocated with
 106  *      MmAllocateNonCachedMemory.
 107  *
 108  * ARGUMENTS
 109  *      BaseAddress
 110  *              Virtual address to be freed;
 111  *
 112  *      NumberOfBytes
 113  *              Size of the region to be freed.
 114  *
 115  * RETURN VALUE
 116  *      None.
 117  *
 118  * NOTE
 119  *      Description taken from include/ddk/mmfuncs.h.
 120  *      Code taken from ntoskrnl/mm/special.c.
 121  *
 122  * REVISIONS
 123  *
 124  */
 125 VOID STDCALL MmFreeNonCachedMemory (IN PVOID BaseAddress,
 126                                     IN ULONG NumberOfBytes)
 127 {
 128   MmFreeMemoryArea (MmGetKernelAddressSpace(),
 129                     BaseAddress,
 130                     NumberOfBytes,
 131                     MmFreeNonCachedPage,
 132                     NULL);
 133 }
 134
 135
 136 /* EOF */