/*

 * i_block.c --- Manage the i_block field for i_blocks

 *

 * Copyright (C) 2008 Theodore Ts'o.

 *

 * %Begin-Header%

 * This file may be redistributed under the terms of the GNU Library

 * General Public License, version 2.

 * %End-Header%

 */

#include "config.h"

#include <stdio.h>

#if HAVE_UNISTD_H

#include <unistd.h>

#endif

#include <time.h>

#include <string.h>

#if HAVE_SYS_STAT_H

#include <sys/stat.h>

#endif

#if HAVE_SYS_TYPES_H

#include <sys/types.h>

#endif

#include <errno.h>

#include "ext2_fs.h"

#include "ext2fs.h"

errcode_t ext2fs_iblk_add_blocks(ext2_filsys fs, struct ext2_inode *inode,

         blk64_t num_blocks)

{

  unsigned long long b = inode->i_blocks;

  if (ext2fs_has_feature_huge_file(fs->super))

    b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;

  if (!ext2fs_has_feature_huge_file(fs->super) ||

      !(inode->i_flags & EXT4_HUGE_FILE_FL))

      num_blocks *= fs->blocksize / 512;

  num_blocks *= EXT2FS_CLUSTER_RATIO(fs);

  b += num_blocks;

  if (ext2fs_has_feature_huge_file(fs->super))

    inode->osd2.linux2.l_i_blocks_hi = b >> 32;

  else if (b > 0xFFFFFFFF)

    return EOVERFLOW;

  inode->i_blocks = b & 0xFFFFFFFF;

  return 0;

}

errcode_t ext2fs_iblk_sub_blocks(ext2_filsys fs, struct ext2_inode *inode,

         blk64_t num_blocks)

{

  unsigned long long b = inode->i_blocks;

  if (ext2fs_has_feature_huge_file(fs->super))

    b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;

  if (!ext2fs_has_feature_huge_file(fs->super) ||

      !(inode->i_flags & EXT4_HUGE_FILE_FL))

      num_blocks *= fs->blocksize / 512;

  num_blocks *= EXT2FS_CLUSTER_RATIO(fs);

  if (num_blocks > b)

    return EOVERFLOW;

  b -= num_blocks;

  if (ext2fs_has_feature_huge_file(fs->super))

    inode->osd2.linux2.l_i_blocks_hi = b >> 32;

  inode->i_blocks = b & 0xFFFFFFFF;

  return 0;

}

errcode_t ext2fs_iblk_set(ext2_filsys fs, struct ext2_inode *inode, blk64_t b)

{

  if (!ext2fs_has_feature_huge_file(fs->super) ||

      !(inode->i_flags & EXT4_HUGE_FILE_FL))

    b *= fs->blocksize / 512;

  b *= EXT2FS_CLUSTER_RATIO(fs);

  inode->i_blocks = b & 0xFFFFFFFF;

  if (ext2fs_has_feature_huge_file(fs->super))

    inode->osd2.linux2.l_i_blocks_hi = b >> 32;

  else if (b >> 32)

    return EOVERFLOW;

  return 0;

}