e2fsprogs/lib/ext2fs/i_block.c

91 lines
2.2 KiB
C

/*
* 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;
}