drivers/fs/ext2/inode.c

   1 /*
   2  * COPYRIGHT:        See COPYING in the top level directory
   3  * PROJECT:          ReactOS kernel
   4  * FILE:             services/fs/ext2/inode.c
   5  * PURPOSE:          Manipulating inodes
   6  * PROGRAMMER:       David Welch (welch@cwcom.net)
   7  * UPDATE HISTORY:
   8  *          26/12/98: Created
   9  */
  10
  11 /* INCLUDES ****************************************************************/
  12
  13 #include <ddk/ntddk.h>
  14
  15 //#define NDEBUG
  16 #include <debug.h>
  17
  18 #include "ext2fs.h"
  19
  20 /* FUNCTIONS ***************************************************************/
  21
  22 struct ext2_group_desc* Ext2LoadGroupDesc(PDEVICE_EXTENSION DeviceExt,
  23                                           ULONG block_group)
  24 {
  25    struct ext2_group_desc* buffer;
  26    ULONG block;
  27    struct ext2_group_desc* gdp;
  28
  29    buffer = ExAllocatePool(NonPagedPool, BLOCKSIZE);
  30
  31    block = block_group / (BLOCKSIZE / sizeof(struct ext2_group_desc));
  32
  33    Ext2ReadSectors(DeviceExt->StorageDevice,
  34                    2 + block,
  35                    1,
  36                    buffer);
  37
  38    gdp = &buffer[block_group % (BLOCKSIZE / sizeof(struct ext2_group_desc))];
  39
  40    DPRINT("gdp->bg_free_blocks_count %d\n",gdp->bg_free_blocks_count);
  41    DPRINT("gdp->bg_inode_table %d\n",gdp->bg_inode_table);
  42
  43    return(gdp);
  44
  45 }
  46
  47 #define INODES_PER_PAGE (PAGE_SIZE / sizeof(struct ext2_inode))
  48 #define INODES_PER_BLOCK (BLOCKSIZE / sizeof(struct ext2_inode))
  49
  50 VOID Ext2LoadInode(PDEVICE_EXTENSION DeviceExt,
  51                    ULONG ino,
  52                    PEXT2_INODE Inode)
  53 {
  54    ULONG block_group;
  55    struct ext2_group_desc* gdp;
  56    ULONG offset;
  57    ULONG dsec;
  58    BOOLEAN Uptodate;
  59    struct ext2_inode* ibuffer;
  60
  61    DPRINT("Ext2LoadInode(DeviceExt %x, ino %d, Inode %x)\n",
  62           DeviceExt, ino, Inode);
  63
  64    block_group = (ino - 1) / DeviceExt->superblock->s_inodes_per_group;
  65
  66    DPRINT("block_group %d\n",block_group);
  67
  68    gdp = Ext2LoadGroupDesc(DeviceExt, block_group);
  69
  70    offset = (ino - 1) % DeviceExt->superblock->s_inodes_per_group;
  71
  72    DPRINT("offset %d\n", offset);
  73
  74    dsec = (gdp->bg_inode_table + (offset / INODES_PER_BLOCK)) * BLOCKSIZE;
  75
  76    DPRINT("dsec %d (dsec/BLOCKSIZE) %d PAGE_ROUND_DOWN(dsec) %d\n",
  77           dsec, (dsec/BLOCKSIZE), PAGE_ROUND_DOWN(dsec));
  78
  79    CcRequestCachePage(DeviceExt->Bcb,
  80                       PAGE_ROUND_DOWN(dsec),
  81                       &Inode->BaseAddress,
  82                       &Uptodate,
  83                       &Inode->CacheSeg);
  84    DPRINT("PAGE_ROUND_DOWN(dsec)/BLOCKSIZE %d\n",
  85           PAGE_ROUND_DOWN(dsec)/BLOCKSIZE);
  86    if (!Uptodate)
  87      {
  88         Ext2ReadSectors(DeviceExt->StorageDevice,
  89                         PAGE_ROUND_DOWN(dsec) / BLOCKSIZE,
  90                         4,
  91                         Inode->BaseAddress);
  92      }
  93    ibuffer = ((struct ext2_inode *)Inode->BaseAddress) +
  94              (dsec - PAGE_ROUND_DOWN(dsec));
  95    DPRINT("Inode->BaseAddress 0x%x ibuffer 0x%x\n",
  96           Inode->BaseAddress, ibuffer);
  97    Inode->inode = &ibuffer[offset % INODES_PER_PAGE];
  98
  99    DPRINT("inode->i_uid %d\n",Inode->inode->i_uid);
 100    DPRINT("inode->i_links_count %d\n",Inode->inode->i_links_count);
 101    DPRINT("inode->i_blocks %d\n",Inode->inode->i_blocks);
 102
 103    DPRINT("Ext2LoadInode() finished\n");
 104 }
 105
 106 VOID Ext2ReleaseInode(PDEVICE_EXTENSION DeviceExt,
 107                       PEXT2_INODE Inode)
 108 {
 109    CcReleaseCachePage(DeviceExt->Bcb,
 110                       Inode->CacheSeg,
 111                       TRUE);
 112    Inode->CacheSeg = NULL;
 113    Inode->BaseAddress = NULL;
 114    Inode->inode = NULL;
 115 }
 116
 117 VOID Ext2ReadInode(PDEVICE_EXTENSION DeviceExt,
 118                    ULONG ino,
 119                    struct ext2_inode* inode)
 120 {
 121    ULONG block_group;
 122    struct ext2_group_desc* gdp;
 123    ULONG offset;
 124    struct ext2_inode* buffer;
 125
 126    DPRINT("Ext2ReadInode(DeviceExt %x, ino %d, inode %x)\n",
 127           DeviceExt,ino,inode);
 128
 129    block_group = (ino - 1) / DeviceExt->superblock->s_inodes_per_group;
 130
 131    gdp = Ext2LoadGroupDesc(DeviceExt, block_group);
 132
 133
 134
 135    offset = (ino - 1) % DeviceExt->superblock->s_inodes_per_group;
 136
 137    buffer = ExAllocatePool(NonPagedPool, BLOCKSIZE);
 138    Ext2ReadSectors(DeviceExt->StorageDevice,
 139                    gdp->bg_inode_table + (offset / INODES_PER_BLOCK),
 140                    1,
 141                    buffer);
 142    memcpy(inode,&buffer[offset % INODES_PER_BLOCK],sizeof(struct ext2_inode));
 143
 144    DPRINT("inode->i_uid %d\n",inode->i_uid);
 145    DPRINT("inode->i_links_count %d\n",inode->i_links_count);
 146    DPRINT("inode->i_blocks %d\n",inode->i_blocks);
 147
 148 }