drivers/filesystems/ntfs/rw.c

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 2002, 2014 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  * PROGRAMMERS:      Art Yerkes
  24  *                   Pierre Schweitzer (pierre@reactos.org)
  25  */
  26
  27 /* INCLUDES *****************************************************************/
  28
  29 #include <ntddk.h>
  30 #include "ntfs.h"
  31
  32 #define NDEBUG
  33 #include <debug.h>
  34
  35 /* FUNCTIONS ****************************************************************/
  36
  37 /*
  38  * FUNCTION: Reads data from a file
  39  */
  40 static
  41 NTSTATUS
  42 NtfsReadFile(PDEVICE_EXTENSION DeviceExt,
  43              PFILE_OBJECT FileObject,
  44              PUCHAR Buffer,
  45              ULONG Length,
  46              ULONG ReadOffset,
  47              ULONG IrpFlags,
  48              PULONG LengthRead)
  49 {
  50     NTSTATUS Status = STATUS_SUCCESS;
  51     PNTFS_FCB Fcb;
  52     PFILE_RECORD_HEADER FileRecord;
  53     PNTFS_ATTR_CONTEXT DataContext;
  54     ULONG RealLength;
  55     ULONG RealReadOffset;
  56     ULONG RealLengthRead;
  57     ULONG ToRead;
  58     BOOLEAN AllocatedBuffer = FALSE;
  59     PCHAR ReadBuffer = (PCHAR)Buffer;
  60
  61     DPRINT1("NtfsReadFile(%p, %p, %p, %u, %u, %x, %p)\n", DeviceExt, FileObject, Buffer, Length, ReadOffset, IrpFlags, LengthRead);
  62
  63     *LengthRead = 0;
  64
  65     if (Length == 0)
  66     {
  67         DPRINT1("Null read!\n");
  68         return STATUS_SUCCESS;
  69     }
  70
  71     Fcb = (PNTFS_FCB)FileObject->FsContext;
  72
  73     if (ReadOffset >= Fcb->Entry.AllocatedSize)
  74     {
  75         DPRINT1("Reading beyond file end!\n");
  76         return STATUS_END_OF_FILE;
  77     }
  78
  79     ToRead = Length;
  80     if (ReadOffset + Length > Fcb->Entry.AllocatedSize)
  81         ToRead = Fcb->Entry.AllocatedSize - ReadOffset;
  82
  83     RealReadOffset = ReadOffset;
  84     RealLength = ToRead;
  85
  86     if ((ReadOffset % DeviceExt->NtfsInfo.BytesPerSector) != 0 || (ToRead % DeviceExt->NtfsInfo.BytesPerSector) != 0)
  87     {
  88         RealReadOffset = ROUND_DOWN(ReadOffset, DeviceExt->NtfsInfo.BytesPerSector);
  89         RealLength = ROUND_UP(ToRead, DeviceExt->NtfsInfo.BytesPerSector);
  90
  91         ReadBuffer = ExAllocatePoolWithTag(NonPagedPool, RealLength + DeviceExt->NtfsInfo.BytesPerSector, TAG_NTFS);
  92         if (ReadBuffer == NULL)
  93         {
  94             DPRINT1("Not enough memory!\n");
  95             return STATUS_INSUFFICIENT_RESOURCES;
  96         }
  97         AllocatedBuffer = TRUE;
  98     }
  99
 100     FileRecord = ExAllocatePoolWithTag(NonPagedPool, DeviceExt->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
 101     if (FileRecord == NULL)
 102     {
 103         DPRINT1("Not enough memory!\n");
 104         return STATUS_INSUFFICIENT_RESOURCES;
 105     }
 106
 107     Status = ReadFileRecord(DeviceExt, Fcb->MFTIndex, FileRecord);
 108     if (!NT_SUCCESS(Status))
 109     {
 110         DPRINT1("Can't find record!\n");
 111         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 112         return Status;
 113     }
 114
 115     Status = FindAttribute(DeviceExt, FileRecord, AttributeData, L"", 0, &DataContext);
 116     if (!NT_SUCCESS(Status))
 117     {
 118         DPRINT1("No data associated with file!\n");
 119         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 120         return Status;
 121     }
 122
 123     DPRINT1("Effective read: %lu at %lu\n", RealLength, RealReadOffset);
 124     RealLengthRead = ReadAttribute(DeviceExt, DataContext, RealReadOffset, (PCHAR)ReadBuffer, RealLength);
 125     if (RealLengthRead != RealLength)
 126     {
 127         DPRINT1("Read failure!\n");
 128         ReleaseAttributeContext(DataContext);
 129         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 130         if (AllocatedBuffer)
 131         {
 132             ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
 133         }
 134         return Status;
 135     }
 136
 137     ReleaseAttributeContext(DataContext);
 138     ExFreePoolWithTag(FileRecord, TAG_NTFS);
 139
 140     *LengthRead = ToRead;
 141
 142     DPRINT1("%lu got read\n", *LengthRead);
 143
 144     if (AllocatedBuffer)
 145     {
 146         RtlCopyMemory(Buffer, ReadBuffer + (ReadOffset - RealReadOffset), ToRead);
 147     }
 148
 149     if (ToRead != Length)
 150     {
 151         RtlZeroMemory(Buffer + ToRead, Length - ToRead);
 152     }
 153
 154     if (AllocatedBuffer)
 155     {
 156         ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
 157     }
 158
 159     return STATUS_SUCCESS;
 160 }
 161
 162
 163 NTSTATUS
 164 NTAPI
 165 NtfsFsdRead(PDEVICE_OBJECT DeviceObject,
 166             PIRP Irp)
 167 {
 168     PDEVICE_EXTENSION DeviceExt;
 169     PIO_STACK_LOCATION Stack;
 170     PFILE_OBJECT FileObject;
 171     PVOID Buffer;
 172     ULONG ReadLength;
 173     LARGE_INTEGER ReadOffset;
 174     ULONG ReturnedReadLength = 0;
 175     NTSTATUS Status = STATUS_SUCCESS;
 176
 177     DPRINT("NtfsRead(DeviceObject %x, Irp %x)\n",DeviceObject,Irp);
 178
 179     DeviceExt = DeviceObject->DeviceExtension;
 180     Stack = IoGetCurrentIrpStackLocation(Irp);
 181     FileObject = Stack->FileObject;
 182
 183     ReadLength = Stack->Parameters.Read.Length;
 184     ReadOffset = Stack->Parameters.Read.ByteOffset;
 185     Buffer = MmGetSystemAddressForMdl(Irp->MdlAddress);
 186
 187     Status = NtfsReadFile(DeviceExt,
 188                           FileObject,
 189                           Buffer,
 190                           ReadLength,
 191                           ReadOffset.u.LowPart,
 192                           Irp->Flags,
 193                           &ReturnedReadLength);
 194     if (NT_SUCCESS(Status))
 195     {
 196         if (FileObject->Flags & FO_SYNCHRONOUS_IO)
 197         {
 198             FileObject->CurrentByteOffset.QuadPart =
 199                 ReadOffset.QuadPart + ReturnedReadLength;
 200         }
 201
 202         Irp->IoStatus.Information = ReturnedReadLength;
 203     }
 204     else
 205     {
 206         Irp->IoStatus.Information = 0;
 207     }
 208
 209     Irp->IoStatus.Status = Status;
 210     IoCompleteRequest(Irp,IO_NO_INCREMENT);
 211
 212     return Status;
 213 }
 214
 215
 216 NTSTATUS
 217 NTAPI
 218 NtfsFsdWrite(PDEVICE_OBJECT DeviceObject,
 219              PIRP Irp)
 220 {
 221     DPRINT("NtfwWrite(DeviceObject %x Irp %x)\n",DeviceObject,Irp);
 222
 223     Irp->IoStatus.Status = STATUS_NOT_SUPPORTED;
 224     Irp->IoStatus.Information = 0;
 225     return STATUS_NOT_SUPPORTED;
 226 }
 227
 228 /* EOF */