1 /*
2 * i_block.c --- Manage the i_block field for i_blocks
3 *
4 * Copyright (C) 2008 Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12 #include <stdio.h>
13 #if HAVE_UNISTD_H
14 #include <unistd.h>
15 #endif
16 #include <time.h>
17 #include <string.h>
18 #if HAVE_SYS_STAT_H
19 #include <sys/stat.h>
20 #endif
21 #if HAVE_SYS_TYPES_H
22 #include <sys/types.h>
23 #endif
24 #include <errno.h>
25
26 #include "ext2_fs.h"
27 #include "ext2fs.h"
28
ext2fs_iblk_add_blocks(ext2_filsys fs,struct ext2_inode * inode,blk64_t num_blocks)29 errcode_t ext2fs_iblk_add_blocks(ext2_filsys fs, struct ext2_inode *inode,
30 blk64_t num_blocks)
31 {
32 unsigned long long b = inode->i_blocks;
33
34 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
35 b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;
36
37 if (!(fs->super->s_feature_ro_compat &
38 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
39 !(inode->i_flags & EXT4_HUGE_FILE_FL))
40 num_blocks *= fs->blocksize / 512;
41 num_blocks *= EXT2FS_CLUSTER_RATIO(fs);
42
43 b += num_blocks;
44
45 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
46 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
47 else if (b > 0xFFFFFFFF)
48 return EOVERFLOW;
49 inode->i_blocks = b & 0xFFFFFFFF;
50 return 0;
51 }
52
ext2fs_iblk_sub_blocks(ext2_filsys fs,struct ext2_inode * inode,blk64_t num_blocks)53 errcode_t ext2fs_iblk_sub_blocks(ext2_filsys fs, struct ext2_inode *inode,
54 blk64_t num_blocks)
55 {
56 unsigned long long b = inode->i_blocks;
57
58 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
59 b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;
60
61 if (!(fs->super->s_feature_ro_compat &
62 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
63 !(inode->i_flags & EXT4_HUGE_FILE_FL))
64 num_blocks *= fs->blocksize / 512;
65 num_blocks *= EXT2FS_CLUSTER_RATIO(fs);
66
67 if (num_blocks > b)
68 return EOVERFLOW;
69
70 b -= num_blocks;
71
72 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
73 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
74 inode->i_blocks = b & 0xFFFFFFFF;
75 return 0;
76 }
77
ext2fs_iblk_set(ext2_filsys fs,struct ext2_inode * inode,blk64_t b)78 errcode_t ext2fs_iblk_set(ext2_filsys fs, struct ext2_inode *inode, blk64_t b)
79 {
80 if (!(fs->super->s_feature_ro_compat &
81 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
82 !(inode->i_flags & EXT4_HUGE_FILE_FL))
83 b *= fs->blocksize / 512;
84 b *= EXT2FS_CLUSTER_RATIO(fs);
85
86 inode->i_blocks = b & 0xFFFFFFFF;
87 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
88 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
89 else if (b >> 32)
90 return EOVERFLOW;
91 return 0;
92 }
93