reactos/ntoskrnl/cc/pin.c

   1 /* $Id: pin.c,v 1.2 2001/12/29 14:32:21 dwelch Exp $
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/cc/pin.c
   6  * PURPOSE:         Implements cache managers pinning interface
   7  * PROGRAMMER:      Hartmut Birr
   8  * UPDATE HISTORY:
   9  *                  Created 05.10.2001
  10  */
  11
  12 /* INCLUDES ******************************************************************/
  13
  14 #include <ddk/ntddk.h>
  15 #include <ddk/ntifs.h>
  16 #include <internal/mm.h>
  17 #include <internal/cc.h>
  18 #include <internal/pool.h>
  19 #include <internal/io.h>
  20 #include <ntos/minmax.h>
  21
  22 #define NDEBUG
  23 #include <internal/debug.h>
  24
  25 /* GLOBALS *******************************************************************/
  26
  27 #define ROUND_DOWN(N, S) ((N) - ((N) % (S)))
  28
  29 /* FUNCTIONS *****************************************************************/
  30
  31 typedef struct _INTERNAL_BCB
  32 {
  33   PUBLIC_BCB PFCB;
  34   PCACHE_SEGMENT CacheSegment;
  35 }
  36 INTERNAL_BCB, *PINTERNAL_BCB;
  37
  38 BOOLEAN STDCALL
  39 CcMapData (
  40    IN PFILE_OBJECT FileObject,
  41    IN PLARGE_INTEGER FileOffset,
  42    IN ULONG Length,
  43    IN BOOLEAN Wait,
  44    OUT PVOID *pBcb,
  45    OUT PVOID *pBuffer)
  46 {
  47    ULONG ReadOffset;
  48    BOOLEAN Valid;
  49    PBCB Bcb;
  50    PCACHE_SEGMENT CacheSeg;
  51    NTSTATUS Status;
  52    PINTERNAL_BCB iBcb;
  53
  54    DPRINT("CcMapData(FileObject %x, FileOffset %d, Length %d, Wait %d,"
  55            " pBcb %x, pBuffer %x)\n", FileObject, (ULONG)FileOffset->QuadPart,
  56            Length, Wait, pBcb, pBuffer);
  57
  58    ReadOffset = FileOffset->QuadPart;
  59    Bcb = ((REACTOS_COMMON_FCB_HEADER*)FileObject->FsContext)->Bcb;
  60
  61    DPRINT("AllocationSize %d, FileSize %d\n",
  62          (ULONG)Bcb->AllocationSize.QuadPart,
  63          (ULONG)Bcb->FileSize.QuadPart);
  64
  65    if (ReadOffset % Bcb->CacheSegmentSize + Length > Bcb->CacheSegmentSize)
  66    {
  67       return FALSE;
  68    }
  69    Status = CcRosRequestCacheSegment(Bcb,
  70                ROUND_DOWN (ReadOffset, Bcb->CacheSegmentSize),
  71                pBuffer,
  72                &Valid,
  73                &CacheSeg);
  74    if (!NT_SUCCESS(Status))
  75    {
  76       return FALSE;
  77    }
  78    if (!Valid)
  79    {
  80       if (!Wait)
  81       {
  82           CcRosReleaseCacheSegment(Bcb, CacheSeg, FALSE, FALSE, FALSE);
  83               return FALSE;
  84       }
  85       if (!NT_SUCCESS(ReadCacheSegment(CacheSeg)))
  86       {
  87         return FALSE;
  88       }
  89    }
  90    *pBuffer += ReadOffset % Bcb->CacheSegmentSize;
  91    iBcb = ExAllocatePool (NonPagedPool, sizeof(INTERNAL_BCB));
  92    if (iBcb == NULL)
  93    {
  94      CcRosReleaseCacheSegment(Bcb, CacheSeg, TRUE, FALSE, FALSE);
  95      return FALSE;
  96    }
  97    iBcb->CacheSegment = CacheSeg;
  98    iBcb->PFCB.MappedLength = Length;
  99    iBcb->PFCB.MappedFileOffset.QuadPart = FileOffset->QuadPart;
 100    *pBcb = (PVOID)iBcb;
 101    return TRUE;
 102 }
 103
 104 VOID STDCALL
 105 CcUnpinData (
 106    IN PVOID Bcb)
 107 {
 108    PINTERNAL_BCB iBcb = Bcb;
 109    CcRosReleaseCacheSegment(iBcb->CacheSegment->Bcb, iBcb->CacheSegment, TRUE, FALSE, FALSE);
 110    ExFreePool(iBcb);
 111 }
 112
 113 VOID STDCALL
 114 CcSetDirtyPinnedData (
 115     IN PVOID Bcb,
 116     IN PLARGE_INTEGER Lsn)
 117 {
 118    PINTERNAL_BCB iBcb = Bcb;
 119    // FIXME: write only the modifyed 4-pages back
 120    WriteCacheSegment(iBcb->CacheSegment);
 121 }
 122