1 /*
2 * online.c --- Do on-line resizing of the ext3 filesystem
3 *
4 * Copyright (C) 2006 by 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 "resize2fs.h"
13 #ifdef HAVE_SYS_IOCTL_H
14 #include <sys/ioctl.h>
15 #endif
16 #include <sys/stat.h>
17 #include <fcntl.h>
18
19 extern char *program_name;
20
online_resize_fs(ext2_filsys fs,const char * mtpt,blk_t * new_size,int flags EXT2FS_ATTR ((unused)))21 errcode_t online_resize_fs(ext2_filsys fs, const char *mtpt,
22 blk_t *new_size, int flags EXT2FS_ATTR((unused)))
23 {
24 #ifdef __linux__
25 struct ext2_new_group_input input;
26 struct ext4_new_group_input input64;
27 struct ext2_super_block *sb = fs->super;
28 unsigned long new_desc_blocks;
29 ext2_filsys new_fs;
30 errcode_t retval;
31 double percent;
32 dgrp_t i;
33 blk_t size;
34 int fd, overhead;
35 int use_old_ioctl = 1;
36
37 printf(_("Filesystem at %s is mounted on %s; "
38 "on-line resizing required\n"), fs->device_name, mtpt);
39
40 if (*new_size < sb->s_blocks_count) {
41 com_err(program_name, 0, _("On-line shrinking not supported"));
42 exit(1);
43 }
44
45 /*
46 * If the number of descriptor blocks is going to increase,
47 * the on-line resizing inode must be present.
48 */
49 new_desc_blocks = ext2fs_div_ceil(
50 ext2fs_div_ceil(*new_size -
51 fs->super->s_first_data_block,
52 EXT2_BLOCKS_PER_GROUP(fs->super)),
53 EXT2_DESC_PER_BLOCK(fs->super));
54 printf("old desc_blocks = %lu, new_desc_blocks = %lu\n",
55 fs->desc_blocks, new_desc_blocks);
56 if (!(fs->super->s_feature_compat &
57 EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
58 new_desc_blocks != fs->desc_blocks) {
59 com_err(program_name, 0,
60 _("Filesystem does not support online resizing"));
61 exit(1);
62 }
63
64 fd = open(mtpt, O_RDONLY);
65 if (fd < 0) {
66 com_err(program_name, errno,
67 _("while trying to open mountpoint %s"), mtpt);
68 exit(1);
69 }
70
71 size=sb->s_blocks_count;
72 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
73 if (errno == EPERM)
74 com_err(program_name, 0,
75 _("Permission denied to resize filesystem"));
76 else if (errno == ENOTTY)
77 com_err(program_name, 0,
78 _("Kernel does not support online resizing"));
79 else
80 com_err(program_name, errno,
81 _("While checking for on-line resizing support"));
82 exit(1);
83 }
84
85 percent = (sb->s_r_blocks_count * 100.0) / sb->s_blocks_count;
86
87 retval = ext2fs_read_bitmaps(fs);
88 if (retval)
89 return retval;
90
91 retval = ext2fs_dup_handle(fs, &new_fs);
92 if (retval)
93 return retval;
94
95 /* The current method of adding one block group at a time to a
96 * mounted filesystem means it is impossible to accomodate the
97 * flex_bg allocation method of placing the metadata together
98 * in a single block group. For now we "fix" this issue by
99 * using the traditional layout for new block groups, where
100 * each block group is self-contained and contains its own
101 * bitmap blocks and inode tables. This means we don't get
102 * the layout advantages of flex_bg in the new block groups,
103 * but at least it allows on-line resizing to function.
104 */
105 new_fs->super->s_feature_incompat &= ~EXT4_FEATURE_INCOMPAT_FLEX_BG;
106 retval = adjust_fs_info(new_fs, fs, 0, *new_size);
107 if (retval)
108 return retval;
109
110 printf(_("Performing an on-line resize of %s to %u (%dk) blocks.\n"),
111 fs->device_name, *new_size, fs->blocksize / 1024);
112
113 size = fs->group_desc_count * sb->s_blocks_per_group +
114 sb->s_first_data_block;
115 if (size > *new_size)
116 size = *new_size;
117
118 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
119 com_err(program_name, errno,
120 _("While trying to extend the last group"));
121 exit(1);
122 }
123
124 for (i = fs->group_desc_count;
125 i < new_fs->group_desc_count; i++) {
126
127 overhead = (int) (2 + new_fs->inode_blocks_per_group);
128
129 if (ext2fs_bg_has_super(new_fs, new_fs->group_desc_count - 1))
130 overhead += 1 + new_fs->desc_blocks +
131 new_fs->super->s_reserved_gdt_blocks;
132
133 input.group = i;
134 input.block_bitmap = new_fs->group_desc[i].bg_block_bitmap;
135 input.inode_bitmap = new_fs->group_desc[i].bg_inode_bitmap;
136 input.inode_table = new_fs->group_desc[i].bg_inode_table;
137 input.blocks_count = sb->s_blocks_per_group;
138 if (i == new_fs->group_desc_count-1) {
139 input.blocks_count = new_fs->super->s_blocks_count -
140 sb->s_first_data_block -
141 (i * sb->s_blocks_per_group);
142 }
143 input.reserved_blocks = (blk_t) (percent * input.blocks_count
144 / 100.0);
145
146 #if 0
147 printf("new block bitmap is at 0x%04x\n", input.block_bitmap);
148 printf("new inode bitmap is at 0x%04x\n", input.inode_bitmap);
149 printf("new inode table is at 0x%04x-0x%04x\n",
150 input.inode_table,
151 input.inode_table + new_fs->inode_blocks_per_group-1);
152 printf("new group has %u blocks\n", input.blocks_count);
153 printf("new group will reserve %d blocks\n",
154 input.reserved_blocks);
155 printf("new group has %d free blocks\n",
156 new_fs->group_desc[i].bg_free_blocks_count);
157 printf("new group has %d free inodes (%d blocks)\n",
158 new_fs->group_desc[i].bg_free_inodes_count,
159 new_fs->inode_blocks_per_group);
160 printf("Adding group #%d\n", input.group);
161 #endif
162
163 if (use_old_ioctl &&
164 ioctl(fd, EXT2_IOC_GROUP_ADD, &input) == 0)
165 continue;
166 else
167 use_old_ioctl = 0;
168
169 input64.group = input.group;
170 input64.block_bitmap = input.block_bitmap;
171 input64.inode_bitmap = input.inode_bitmap;
172 input64.inode_table = input.inode_table;
173 input64.blocks_count = input.blocks_count;
174 input64.reserved_blocks = input.reserved_blocks;
175 input64.unused = input.unused;
176
177 if (ioctl(fd, EXT4_IOC_GROUP_ADD, &input64) < 0) {
178 com_err(program_name, errno,
179 _("While trying to add group #%d"),
180 input.group);
181 exit(1);
182 }
183 }
184
185 ext2fs_free(new_fs);
186 close(fd);
187
188 return 0;
189 #else
190 printf(_("Filesystem at %s is mounted on %s, and on-line resizing is "
191 "not supported on this system.\n"), fs->device_name, mtpt);
192 exit(1);
193 #endif
194 }
195