drivers/filesystems/ntfs/rw.c

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 2002 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  18  *
  19  * COPYRIGHT:        See COPYING in the top level directory
  20  * PROJECT:          ReactOS kernel
  21  * FILE:             drivers/filesystem/ntfs/rw.c
  22  * PURPOSE:          NTFS filesystem driver
  23  * PROGRAMMER:       Art Yerkes
  24  * UPDATE HISTORY:
  25  */
  26
  27 /* INCLUDES *****************************************************************/
  28
  29 #include <ntddk.h>
  30 #include "ntfs.h"
  31
  32 #define NDEBUG
  33 #include <debug.h>
  34
  35 /* GLOBALS *******************************************************************/
  36
  37 #define ROUND_UP(N, S) ((((N) + (S) - 1) / (S)) * (S))
  38 #define ROUND_DOWN(N, S) ((N) - ((N) % (S)))
  39
  40 /* FUNCTIONS ****************************************************************/
  41
  42 /*
  43  * FUNCTION: Reads data from a file
  44  */
  45 static
  46 NTSTATUS
  47 NtfsReadFile(PDEVICE_EXTENSION DeviceExt,
  48              PFILE_OBJECT FileObject,
  49              PUCHAR Buffer,
  50              ULONG Length,
  51              ULONG ReadOffset,
  52              ULONG IrpFlags,
  53              PULONG LengthRead)
  54 {
  55 #if 0
  56   NTSTATUS Status = STATUS_SUCCESS;
  57   PUCHAR TempBuffer;
  58   ULONG TempLength;
  59   PCCB Ccb;
  60   PFCB Fcb;
  61
  62   DPRINT("CdfsReadFile(ReadOffset %lu  Length %lu)\n", ReadOffset, Length);
  63
  64   *LengthRead = 0;
  65
  66   if (Length == 0)
  67     return(STATUS_SUCCESS);
  68
  69   Ccb = (PCCB)FileObject->FsContext2;
  70   Fcb = (PFCB)FileObject->FsContext;
  71
  72   if (ReadOffset >= Fcb->Entry.DataLengthL)
  73     return(STATUS_END_OF_FILE);
  74
  75   DPRINT("Reading %d bytes at %d\n", Length, ReadOffset);
  76
  77   if (!(IrpFlags & (IRP_NOCACHE|IRP_PAGING_IO)))
  78     {
  79       LARGE_INTEGER FileOffset;
  80       IO_STATUS_BLOCK IoStatus;
  81
  82       if (ReadOffset + Length > Fcb->Entry.DataLengthL)
  83          Length = Fcb->Entry.DataLengthL - ReadOffset;
  84       if (FileObject->PrivateCacheMap == NULL)
  85       {
  86           CcRosInitializeFileCache(FileObject, PAGE_SIZE);
  87       }
  88
  89       FileOffset.QuadPart = (LONGLONG)ReadOffset;
  90       CcCopyRead(FileObject,
  91                  &FileOffset,
  92                  Length,
  93                  TRUE,
  94                  Buffer,
  95                  &IoStatus);
  96       *LengthRead = IoStatus.Information;
  97
  98       return(IoStatus.Status);
  99     }
 100
 101   if ((ReadOffset % BLOCKSIZE) != 0 || (Length % BLOCKSIZE) != 0)
 102     {
 103       return STATUS_INVALID_PARAMETER;
 104     }
 105   if (ReadOffset + Length > ROUND_UP(Fcb->Entry.DataLengthL, BLOCKSIZE))
 106     Length = ROUND_UP(Fcb->Entry.DataLengthL, BLOCKSIZE) - ReadOffset;
 107
 108   Status = CdfsReadSectors(DeviceExt->StorageDevice,
 109                            Fcb->Entry.ExtentLocationL + (ReadOffset / BLOCKSIZE),
 110                            Length / BLOCKSIZE,
 111                            Buffer);
 112   if (NT_SUCCESS(Status))
 113     {
 114       *LengthRead = Length;
 115       if (Length + ReadOffset > Fcb->Entry.DataLengthL)
 116       {
 117         memset(Buffer + Fcb->Entry.DataLengthL - ReadOffset,
 118                0, Length + ReadOffset - Fcb->Entry.DataLengthL);
 119       }
 120     }
 121
 122   return(Status);
 123 #else
 124     UNREFERENCED_PARAMETER(DeviceExt);
 125     UNREFERENCED_PARAMETER(FileObject);
 126     UNREFERENCED_PARAMETER(Buffer);
 127     UNREFERENCED_PARAMETER(Length);
 128     UNREFERENCED_PARAMETER(ReadOffset);
 129     UNREFERENCED_PARAMETER(IrpFlags);
 130     *LengthRead = 0;
 131     return STATUS_END_OF_FILE;
 132 #endif
 133 }
 134
 135
 136 NTSTATUS
 137 NTAPI
 138 NtfsFsdRead(PDEVICE_OBJECT DeviceObject,
 139             PIRP Irp)
 140 {
 141     PDEVICE_EXTENSION DeviceExt;
 142     PIO_STACK_LOCATION Stack;
 143     PFILE_OBJECT FileObject;
 144     PVOID Buffer;
 145     ULONG ReadLength;
 146     LARGE_INTEGER ReadOffset;
 147     ULONG ReturnedReadLength = 0;
 148     NTSTATUS Status = STATUS_SUCCESS;
 149
 150     DPRINT("NtfsRead(DeviceObject %x, Irp %x)\n",DeviceObject,Irp);
 151
 152     DeviceExt = DeviceObject->DeviceExtension;
 153     Stack = IoGetCurrentIrpStackLocation(Irp);
 154     FileObject = Stack->FileObject;
 155
 156     ReadLength = Stack->Parameters.Read.Length;
 157     ReadOffset = Stack->Parameters.Read.ByteOffset;
 158     Buffer = MmGetSystemAddressForMdl(Irp->MdlAddress);
 159
 160     Status = NtfsReadFile(DeviceExt,
 161                           FileObject,
 162                           Buffer,
 163                           ReadLength,
 164                           ReadOffset.u.LowPart,
 165                           Irp->Flags,
 166                           &ReturnedReadLength);
 167     if (NT_SUCCESS(Status))
 168     {
 169         if (FileObject->Flags & FO_SYNCHRONOUS_IO)
 170         {
 171             FileObject->CurrentByteOffset.QuadPart =
 172                 ReadOffset.QuadPart + ReturnedReadLength;
 173         }
 174
 175         Irp->IoStatus.Information = ReturnedReadLength;
 176     }
 177     else
 178     {
 179         Irp->IoStatus.Information = 0;
 180     }
 181
 182     Irp->IoStatus.Status = Status;
 183     IoCompleteRequest(Irp,IO_NO_INCREMENT);
 184
 185     return Status;
 186 }
 187
 188
 189 NTSTATUS
 190 NTAPI
 191 NtfsFsdWrite(PDEVICE_OBJECT DeviceObject,
 192              PIRP Irp)
 193 {
 194     DPRINT("NtfwWrite(DeviceObject %x Irp %x)\n",DeviceObject,Irp);
 195
 196     Irp->IoStatus.Status = STATUS_NOT_SUPPORTED;
 197     Irp->IoStatus.Information = 0;
 198     return STATUS_NOT_SUPPORTED;
 199 }
 200
 201 /* EOF */