reactos/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     ULONGLONG StreamSize;
  61
  62     DPRINT1("NtfsReadFile(%p, %p, %p, %u, %u, %x, %p)\n", DeviceExt, FileObject, Buffer, Length, ReadOffset, IrpFlags, LengthRead);
  63
  64     *LengthRead = 0;
  65
  66     if (Length == 0)
  67     {
  68         DPRINT1("Null read!\n");
  69         return STATUS_SUCCESS;
  70     }
  71
  72     Fcb = (PNTFS_FCB)FileObject->FsContext;
  73
  74     if (NtfsFCBIsCompressed(Fcb))
  75     {
  76         DPRINT1("Compressed file!\n");
  77         UNIMPLEMENTED;
  78         return STATUS_NOT_IMPLEMENTED;
  79     }
  80
  81     FileRecord = ExAllocatePoolWithTag(NonPagedPool, DeviceExt->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
  82     if (FileRecord == NULL)
  83     {
  84         DPRINT1("Not enough memory!\n");
  85         return STATUS_INSUFFICIENT_RESOURCES;
  86     }
  87
  88     Status = ReadFileRecord(DeviceExt, Fcb->MFTIndex, FileRecord);
  89     if (!NT_SUCCESS(Status))
  90     {
  91         DPRINT1("Can't find record!\n");
  92         ExFreePoolWithTag(FileRecord, TAG_NTFS);
  93         return Status;
  94     }
  95
  96
  97     Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream, wcslen(Fcb->Stream), &DataContext);
  98     if (!NT_SUCCESS(Status))
  99     {
 100         NTSTATUS BrowseStatus;
 101         FIND_ATTR_CONTXT Context;
 102         PNTFS_ATTR_RECORD Attribute;
 103
 104         DPRINT1("No '%S' data stream associated with file!\n", Fcb->Stream);
 105
 106         BrowseStatus = FindFirstAttribute(&Context, DeviceExt, FileRecord, FALSE, &Attribute);
 107         while (NT_SUCCESS(BrowseStatus))
 108         {
 109             if (Attribute->Type == AttributeData)
 110             {
 111                 UNICODE_STRING Name;
 112
 113                 Name.Length = Attribute->NameLength * sizeof(WCHAR);
 114                 Name.MaximumLength = Name.Length;
 115                 Name.Buffer = (PWCHAR)((ULONG_PTR)Attribute + Attribute->NameOffset);
 116                 DPRINT1("Data stream: '%wZ' available\n", &Name);
 117             }
 118
 119             BrowseStatus = FindNextAttribute(&Context, &Attribute);
 120         }
 121         FindCloseAttribute(&Context);
 122
 123         ReleaseAttributeContext(DataContext);
 124         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 125         return Status;
 126     }
 127
 128     StreamSize = AttributeDataLength(&DataContext->Record);
 129     if (ReadOffset >= StreamSize)
 130     {
 131         DPRINT1("Reading beyond stream end!\n");
 132         ReleaseAttributeContext(DataContext);
 133         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 134         return STATUS_END_OF_FILE;
 135     }
 136
 137     ToRead = Length;
 138     if (ReadOffset + Length > StreamSize)
 139         ToRead = StreamSize - ReadOffset;
 140
 141     RealReadOffset = ReadOffset;
 142     RealLength = ToRead;
 143
 144     if ((ReadOffset % DeviceExt->NtfsInfo.BytesPerSector) != 0 || (ToRead % DeviceExt->NtfsInfo.BytesPerSector) != 0)
 145     {
 146         RealReadOffset = ROUND_DOWN(ReadOffset, DeviceExt->NtfsInfo.BytesPerSector);
 147         RealLength = ROUND_UP(ToRead, DeviceExt->NtfsInfo.BytesPerSector);
 148
 149         ReadBuffer = ExAllocatePoolWithTag(NonPagedPool, RealLength + DeviceExt->NtfsInfo.BytesPerSector, TAG_NTFS);
 150         if (ReadBuffer == NULL)
 151         {
 152             DPRINT1("Not enough memory!\n");
 153             ReleaseAttributeContext(DataContext);
 154             ExFreePoolWithTag(FileRecord, TAG_NTFS);
 155             return STATUS_INSUFFICIENT_RESOURCES;
 156         }
 157         AllocatedBuffer = TRUE;
 158     }
 159
 160     DPRINT1("Effective read: %lu at %lu for stream '%S'\n", RealLength, RealReadOffset, Fcb->Stream);
 161     RealLengthRead = ReadAttribute(DeviceExt, DataContext, RealReadOffset, (PCHAR)ReadBuffer, RealLength);
 162     if (RealLengthRead == 0)
 163     {
 164         DPRINT1("Read failure!\n");
 165         ReleaseAttributeContext(DataContext);
 166         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 167         if (AllocatedBuffer)
 168         {
 169             ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
 170         }
 171         return Status;
 172     }
 173
 174     ReleaseAttributeContext(DataContext);
 175     ExFreePoolWithTag(FileRecord, TAG_NTFS);
 176
 177     *LengthRead = ToRead;
 178
 179     DPRINT1("%lu got read\n", *LengthRead);
 180
 181     if (AllocatedBuffer)
 182     {
 183         RtlCopyMemory(Buffer, ReadBuffer + (ReadOffset - RealReadOffset), ToRead);
 184     }
 185
 186     if (ToRead != Length)
 187     {
 188         RtlZeroMemory(Buffer + ToRead, Length - ToRead);
 189     }
 190
 191     if (AllocatedBuffer)
 192     {
 193         ExFreePoolWithTag(ReadBuffer, TAG_NTFS);
 194     }
 195
 196     return STATUS_SUCCESS;
 197 }
 198
 199
 200 NTSTATUS
 201 NtfsRead(PNTFS_IRP_CONTEXT IrpContext)
 202 {
 203     PDEVICE_EXTENSION DeviceExt;
 204     PIO_STACK_LOCATION Stack;
 205     PFILE_OBJECT FileObject;
 206     PVOID Buffer;
 207     ULONG ReadLength;
 208     LARGE_INTEGER ReadOffset;
 209     ULONG ReturnedReadLength = 0;
 210     NTSTATUS Status = STATUS_SUCCESS;
 211     PIRP Irp;
 212     PDEVICE_OBJECT DeviceObject;
 213
 214     DPRINT("NtfsRead(IrpContext %p)\n", IrpContext);
 215
 216     DeviceObject = IrpContext->DeviceObject;
 217     Irp = IrpContext->Irp;
 218     Stack = IrpContext->Stack;
 219     FileObject = IrpContext->FileObject;
 220
 221     DeviceExt = DeviceObject->DeviceExtension;
 222     ReadLength = Stack->Parameters.Read.Length;
 223     ReadOffset = Stack->Parameters.Read.ByteOffset;
 224     Buffer = NtfsGetUserBuffer(Irp, BooleanFlagOn(Irp->Flags, IRP_PAGING_IO));
 225
 226     Status = NtfsReadFile(DeviceExt,
 227                           FileObject,
 228                           Buffer,
 229                           ReadLength,
 230                           ReadOffset.u.LowPart,
 231                           Irp->Flags,
 232                           &ReturnedReadLength);
 233     if (NT_SUCCESS(Status))
 234     {
 235         if (FileObject->Flags & FO_SYNCHRONOUS_IO)
 236         {
 237             FileObject->CurrentByteOffset.QuadPart =
 238                 ReadOffset.QuadPart + ReturnedReadLength;
 239         }
 240
 241         Irp->IoStatus.Information = ReturnedReadLength;
 242     }
 243     else
 244     {
 245         Irp->IoStatus.Information = 0;
 246     }
 247
 248     return Status;
 249 }
 250
 251
 252 NTSTATUS
 253 NtfsWrite(PNTFS_IRP_CONTEXT IrpContext)
 254 {
 255     DPRINT("NtfsWrite(IrpContext %p)\n",IrpContext);
 256
 257     IrpContext->Irp->IoStatus.Information = 0;
 258     return STATUS_NOT_SUPPORTED;
 259 }
 260
 261 /* EOF */