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  * @implemented
  47  */
  48 PVOID STDCALL
  49 MmAllocateNonCachedMemory(IN ULONG NumberOfBytes)
  50 {
  51    PVOID Result;
  52    MEMORY_AREA* marea;
  53    NTSTATUS Status;
  54    ULONG i;
  55    ULONG Attributes;
  56
  57    MmLockAddressSpace(MmGetKernelAddressSpace());
  58    Result = NULL;
  59    Status = MmCreateMemoryArea (NULL,
  60                                 MmGetKernelAddressSpace(),
  61                                 MEMORY_AREA_NO_CACHE,
  62                                 &Result,
  63                                 NumberOfBytes,
  64                                 0,
  65                                 &marea,
  66                                 FALSE,
  67                                 FALSE);
  68    MmUnlockAddressSpace(MmGetKernelAddressSpace());
  69
  70    if (!NT_SUCCESS(Status))
  71      {
  72         return (NULL);
  73      }
  74    Attributes = PAGE_READWRITE | PAGE_SYSTEM | PAGE_NOCACHE |
  75      PAGE_WRITETHROUGH;
  76    for (i = 0; i < (PAGE_ROUND_UP(NumberOfBytes) / PAGE_SIZE); i++)
  77      {
  78        PHYSICAL_ADDRESS NPage;
  79
  80        Status = MmRequestPageMemoryConsumer(MC_NPPOOL, TRUE, &NPage);
  81        MmCreateVirtualMapping (NULL,
  82                                Result + (i * PAGE_SIZE),
  83                                Attributes,
  84                                NPage,
  85                                TRUE);
  86      }
  87    return ((PVOID)Result);
  88 }
  89
  90 VOID STATIC
  91 MmFreeNonCachedPage(PVOID Context, MEMORY_AREA* MemoryArea, PVOID Address,
  92                     PHYSICAL_ADDRESS PhysAddr, SWAPENTRY SwapEntry,
  93                     BOOLEAN Dirty)
  94 {
  95   assert(SwapEntry == 0);
  96   if (PhysAddr.QuadPart != 0)
  97     {
  98       MmReleasePageMemoryConsumer(MC_NPPOOL, PhysAddr);
  99     }
 100 }
 101
 102 /**********************************************************************
 103  * NAME                                                 EXPORTED
 104  *      MmFreeNonCachedMemory@8
 105  *
 106  * DESCRIPTION
 107  *      Releases a range of noncached memory allocated with
 108  *      MmAllocateNonCachedMemory.
 109  *
 110  * ARGUMENTS
 111  *      BaseAddress
 112  *              Virtual address to be freed;
 113  *
 114  *      NumberOfBytes
 115  *              Size of the region to be freed.
 116  *
 117  * RETURN VALUE
 118  *      None.
 119  *
 120  * NOTE
 121  *      Description taken from include/ddk/mmfuncs.h.
 122  *      Code taken from ntoskrnl/mm/special.c.
 123  *
 124  * REVISIONS
 125  *
 126  * @implemented
 127  */
 128 VOID STDCALL MmFreeNonCachedMemory (IN PVOID BaseAddress,
 129                                     IN ULONG NumberOfBytes)
 130 {
 131   MmLockAddressSpace(MmGetKernelAddressSpace());
 132   MmFreeMemoryArea (MmGetKernelAddressSpace(),
 133                     BaseAddress,
 134                     NumberOfBytes,
 135                     MmFreeNonCachedPage,
 136                     NULL);
 137   MmUnlockAddressSpace(MmGetKernelAddressSpace());
 138 }
 139
 140 /* EOF */