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 printf(_("On-line shrinking from %u to %u not supported.\n"),
42 sb->s_blocks_count, *new_size);
43 exit(1);
44 }
45
46 /*
47 * If the number of descriptor blocks is going to increase,
48 * the on-line resizing inode must be present.
49 */
50 new_desc_blocks = ext2fs_div_ceil(
51 ext2fs_div_ceil(*new_size -
52 fs->super->s_first_data_block,
53 EXT2_BLOCKS_PER_GROUP(fs->super)),
54 EXT2_DESC_PER_BLOCK(fs->super));
55 printf("old desc_blocks = %lu, new_desc_blocks = %lu\n",
56 fs->desc_blocks, new_desc_blocks);
57 if (!(fs->super->s_feature_compat &
58 EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
59 new_desc_blocks != fs->desc_blocks) {
60 com_err(program_name, 0,
61 _("Filesystem does not support online resizing"));
62 exit(1);
63 }
64
65 fd = open(mtpt, O_RDONLY);
66 if (fd < 0) {
67 com_err(program_name, errno,
68 _("while trying to open mountpoint %s"), mtpt);
69 exit(1);
70 }
71
72 size=sb->s_blocks_count;
73 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
74 if (errno == EPERM)
75 com_err(program_name, 0,
76 _("Permission denied to resize filesystem"));
77 else if (errno == ENOTTY)
78 com_err(program_name, 0,
79 _("Kernel does not support online resizing"));
80 else
81 com_err(program_name, errno,
82 _("While checking for on-line resizing support"));
83 exit(1);
84 }
85
86 percent = (sb->s_r_blocks_count * 100.0) / sb->s_blocks_count;
87
88 retval = ext2fs_read_bitmaps(fs);
89 if (retval)
90 return retval;
91
92 retval = ext2fs_dup_handle(fs, &new_fs);
93 if (retval)
94 return retval;
95
96 /* The current method of adding one block group at a time to a
97 * mounted filesystem means it is impossible to accomodate the
98 * flex_bg allocation method of placing the metadata together
99 * in a single block group. For now we "fix" this issue by
100 * using the traditional layout for new block groups, where
101 * each block group is self-contained and contains its own
102 * bitmap blocks and inode tables. This means we don't get
103 * the layout advantages of flex_bg in the new block groups,
104 * but at least it allows on-line resizing to function.
105 */
106 new_fs->super->s_feature_incompat &= ~EXT4_FEATURE_INCOMPAT_FLEX_BG;
107 retval = adjust_fs_info(new_fs, fs, 0, *new_size);
108 if (retval)
109 return retval;
110
111 printf(_("Performing an on-line resize of %s to %u (%dk) blocks.\n"),
112 fs->device_name, *new_size, fs->blocksize / 1024);
113
114 size = fs->group_desc_count * sb->s_blocks_per_group +
115 sb->s_first_data_block;
116 if (size > *new_size)
117 size = *new_size;
118
119 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) {
120 com_err(program_name, errno,
121 _("While trying to extend the last group"));
122 exit(1);
123 }
124
125 for (i = fs->group_desc_count;
126 i < new_fs->group_desc_count; i++) {
127
128 overhead = (int) (2 + new_fs->inode_blocks_per_group);
129
130 if (ext2fs_bg_has_super(new_fs, new_fs->group_desc_count - 1))
131 overhead += 1 + new_fs->desc_blocks +
132 new_fs->super->s_reserved_gdt_blocks;
133
134 input.group = i;
135 input.block_bitmap = new_fs->group_desc[i].bg_block_bitmap;
136 input.inode_bitmap = new_fs->group_desc[i].bg_inode_bitmap;
137 input.inode_table = new_fs->group_desc[i].bg_inode_table;
138 input.blocks_count = sb->s_blocks_per_group;
139 if (i == new_fs->group_desc_count-1) {
140 input.blocks_count = new_fs->super->s_blocks_count -
141 sb->s_first_data_block -
142 (i * sb->s_blocks_per_group);
143 }
144 input.reserved_blocks = (blk_t) (percent * input.blocks_count
145 / 100.0);
146
147 #if 0
148 printf("new block bitmap is at 0x%04x\n", input.block_bitmap);
149 printf("new inode bitmap is at 0x%04x\n", input.inode_bitmap);
150 printf("new inode table is at 0x%04x-0x%04x\n",
151 input.inode_table,
152 input.inode_table + new_fs->inode_blocks_per_group-1);
153 printf("new group has %u blocks\n", input.blocks_count);
154 printf("new group will reserve %d blocks\n",
155 input.reserved_blocks);
156 printf("new group has %d free blocks\n",
157 new_fs->group_desc[i].bg_free_blocks_count);
158 printf("new group has %d free inodes (%d blocks)\n",
159 new_fs->group_desc[i].bg_free_inodes_count,
160 new_fs->inode_blocks_per_group);
161 printf("Adding group #%d\n", input.group);
162 #endif
163
164 if (use_old_ioctl &&
165 ioctl(fd, EXT2_IOC_GROUP_ADD, &input) == 0)
166 continue;
167 else
168 use_old_ioctl = 0;
169
170 input64.group = input.group;
171 input64.block_bitmap = input.block_bitmap;
172 input64.inode_bitmap = input.inode_bitmap;
173 input64.inode_table = input.inode_table;
174 input64.blocks_count = input.blocks_count;
175 input64.reserved_blocks = input.reserved_blocks;
176 input64.unused = input.unused;
177
178 if (ioctl(fd, EXT4_IOC_GROUP_ADD, &input64) < 0) {
179 com_err(program_name, errno,
180 _("While trying to add group #%d"),
181 input.group);
182 exit(1);
183 }
184 }
185
186 ext2fs_free(new_fs);
187 close(fd);
188
189 return 0;
190 #else
191 printf(_("Filesystem at %s is mounted on %s, and on-line resizing is "
192 "not supported on this system.\n"), fs->device_name, mtpt);
193 exit(1);
194 #endif
195 }
196