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 Public
8 * License.
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 &
35 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
36 !(inode->i_flags & EXT4_HUGE_FILE_FL))
37 num_blocks *= fs->blocksize / 512;
38
39 b += num_blocks;
40
41 if (fs->super->s_feature_ro_compat &
42 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) {
43 b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;
44 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
45 } else if (b > 0xFFFFFFFF)
46 return EOVERFLOW;
47 inode->i_blocks = b & 0xFFFFFFFF;
48 return 0;
49 }
50
ext2fs_iblk_sub_blocks(ext2_filsys fs,struct ext2_inode * inode,blk64_t num_blocks)51 errcode_t ext2fs_iblk_sub_blocks(ext2_filsys fs, struct ext2_inode *inode,
52 blk64_t num_blocks)
53 {
54 unsigned long long b = inode->i_blocks;
55
56 if (!(fs->super->s_feature_ro_compat &
57 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
58 !(inode->i_flags & EXT4_HUGE_FILE_FL))
59 num_blocks *= fs->blocksize / 512;
60
61 if (num_blocks > b)
62 return EOVERFLOW;
63
64 b -= num_blocks;
65
66 if (fs->super->s_feature_ro_compat &
67 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) {
68 b += ((long long) inode->osd2.linux2.l_i_blocks_hi) << 32;
69 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
70 }
71 inode->i_blocks = b & 0xFFFFFFFF;
72 return 0;
73 }
74
ext2fs_iblk_set(ext2_filsys fs,struct ext2_inode * inode,blk64_t b)75 errcode_t ext2fs_iblk_set(ext2_filsys fs, struct ext2_inode *inode, blk64_t b)
76 {
77 if (!(fs->super->s_feature_ro_compat &
78 EXT4_FEATURE_RO_COMPAT_HUGE_FILE) ||
79 !(inode->i_flags & EXT4_HUGE_FILE_FL))
80 b *= fs->blocksize / 512;
81
82 inode->i_blocks = b & 0xFFFFFFFF;
83 if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
84 inode->osd2.linux2.l_i_blocks_hi = b >> 32;
85 else if (b >> 32)
86 return EOVERFLOW;
87 return 0;
88 }
89