reactos/drivers/fs/ext2/file.c

   1 /*
   2  * COPYRIGHT:        See COPYING in the top level directory
   3  * PROJECT:          ReactOS kernel
   4  * FILE:             services/fs/ext2/super.c
   5  * PURPOSE:          ext2 filesystem
   6  * PROGRAMMER:       David Welch (welch@mcmail.com)
   7  * UPDATE HISTORY:
   8  */
   9
  10 /* INCLUDES *****************************************************************/
  11
  12 #include <ddk/ntddk.h>
  13
  14 #define NDEBUG
  15 #include <internal/debug.h>
  16
  17 #include "ext2fs.h"
  18
  19 /* FUNCTIONS ****************************************************************/
  20
  21 #define addr_per_block (BLOCKSIZE / sizeof(ULONG))
  22
  23 ULONG Ext2BlockMap(PDEVICE_EXTENSION DeviceExt,
  24                   struct ext2_inode* inode,
  25                   ULONG offset)
  26 {
  27    ULONG block;
  28    PULONG TempBuffer;
  29    BOOL b;
  30
  31    DPRINT("Ext2BlockMap(DeviceExt %x, inode %x, offset %d)\n",
  32            DeviceExt,inode,offset);
  33    if (offset < EXT2_NDIR_BLOCKS)
  34      {
  35         block = inode->i_block[offset];
  36         DPRINT("block %d\n",block);
  37         return(block);
  38      }
  39    offset = offset - EXT2_NDIR_BLOCKS;
  40    if (offset < addr_per_block)
  41      {
  42         block = inode->i_block[EXT2_IND_BLOCK];
  43         TempBuffer = ExAllocatePool(NonPagedPool, BLOCKSIZE);
  44         b = Ext2ReadSectors(DeviceExt->StorageDevice,
  45                             block,
  46                             1,
  47                             TempBuffer);
  48         if (!b)
  49           {
  50              DbgPrint("ext2fs:%s:%d: Disk io failed\n", __FILE__, __LINE__);
  51              return(0);
  52           }
  53         block = TempBuffer[offset];
  54         ExFreePool(TempBuffer);
  55         return(block);
  56      }
  57    offset = offset - addr_per_block;
  58    DbgPrint("Failed at %s:%d\n",__FILE__,__LINE__);
  59    for(;;);
  60 }
  61