1 /*
2 * alloc_tables.c --- Allocate tables for a newly initialized
3 * filesystem. Used by mke2fs when initializing a filesystem
4 *
5 * Copyright (C) 1996 Theodore Ts'o.
6 *
7 * %Begin-Header%
8 * This file may be redistributed under the terms of the GNU Library
9 * General Public License, version 2.
10 * %End-Header%
11 */
12
13 #include <stdio.h>
14 #include <string.h>
15 #if HAVE_UNISTD_H
16 #include <unistd.h>
17 #endif
18 #include <fcntl.h>
19 #include <time.h>
20 #if HAVE_SYS_STAT_H
21 #include <sys/stat.h>
22 #endif
23 #if HAVE_SYS_TYPES_H
24 #include <sys/types.h>
25 #endif
26
27 #include "ext2_fs.h"
28 #include "ext2fs.h"
29 #include "ext2fsP.h"
30
31 /*
32 * This routine searches for free blocks that can allocate a full
33 * group of bitmaps or inode tables for a flexbg group. Returns the
34 * block number with a correct offset were the bitmaps and inode
35 * tables can be allocated continously and in order.
36 */
flexbg_offset(ext2_filsys fs,dgrp_t group,blk64_t start_blk,ext2fs_block_bitmap bmap,int rem_grp,int elem_size)37 static blk64_t flexbg_offset(ext2_filsys fs, dgrp_t group, blk64_t start_blk,
38 ext2fs_block_bitmap bmap, int rem_grp,
39 int elem_size)
40 {
41 int flexbg, flexbg_size, size;
42 blk64_t last_blk, first_free = 0;
43 dgrp_t last_grp;
44
45 flexbg_size = 1 << fs->super->s_log_groups_per_flex;
46 flexbg = group / flexbg_size;
47 size = rem_grp * elem_size;
48
49 if (size > (int) (fs->super->s_blocks_per_group / 8))
50 size = (int) fs->super->s_blocks_per_group / 8;
51
52 /*
53 * Don't do a long search if the previous block
54 * search is still valid.
55 */
56 if (start_blk && ext2fs_test_block_bitmap_range2(bmap, start_blk,
57 elem_size))
58 return start_blk;
59
60 start_blk = ext2fs_group_first_block2(fs, flexbg_size * flexbg);
61 last_grp = group | (flexbg_size - 1);
62 if (last_grp > fs->group_desc_count-1)
63 last_grp = fs->group_desc_count-1;
64 last_blk = ext2fs_group_last_block2(fs, last_grp);
65
66 /* Find the first available block */
67 if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, size,
68 bmap, &first_free) == 0)
69 return first_free;
70
71 if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, elem_size,
72 bmap, &first_free) == 0)
73 return first_free;
74
75 if (ext2fs_get_free_blocks2(fs, 0, last_blk, elem_size, bmap,
76 &first_free) == 0)
77 return first_free;
78
79 return first_free;
80 }
81
ext2fs_allocate_group_table(ext2_filsys fs,dgrp_t group,ext2fs_block_bitmap bmap)82 errcode_t ext2fs_allocate_group_table(ext2_filsys fs, dgrp_t group,
83 ext2fs_block_bitmap bmap)
84 {
85 unsigned int j;
86 errcode_t retval;
87 blk64_t group_blk, start_blk, last_blk, new_blk, blk;
88 dgrp_t last_grp = 0;
89 int rem_grps = 0, flexbg_size = 0;
90
91 group_blk = ext2fs_group_first_block2(fs, group);
92 last_blk = ext2fs_group_last_block2(fs, group);
93
94 if (!bmap)
95 bmap = fs->block_map;
96
97 if (EXT2_HAS_INCOMPAT_FEATURE(fs->super,
98 EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
99 fs->super->s_log_groups_per_flex) {
100 flexbg_size = 1 << fs->super->s_log_groups_per_flex;
101 last_grp = group | (flexbg_size - 1);
102 if (last_grp > fs->group_desc_count-1)
103 last_grp = fs->group_desc_count-1;
104 rem_grps = last_grp - group + 1;
105 }
106
107 /*
108 * Allocate the block and inode bitmaps, if necessary
109 */
110 if (fs->stride) {
111 retval = ext2fs_get_free_blocks2(fs, group_blk, last_blk,
112 1, bmap, &start_blk);
113 if (retval)
114 return retval;
115 start_blk += fs->inode_blocks_per_group;
116 start_blk += ((fs->stride * group) %
117 (last_blk - start_blk + 1));
118 if (start_blk >= last_blk)
119 start_blk = group_blk;
120 } else
121 start_blk = group_blk;
122
123 if (flexbg_size) {
124 blk64_t prev_block = 0;
125
126 if (group % flexbg_size)
127 prev_block = ext2fs_block_bitmap_loc(fs, group - 1) + 1;
128 start_blk = flexbg_offset(fs, group, prev_block, bmap,
129 rem_grps, 1);
130 last_blk = ext2fs_group_last_block2(fs, last_grp);
131 }
132
133 if (!ext2fs_block_bitmap_loc(fs, group)) {
134 retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
135 1, bmap, &new_blk);
136 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
137 retval = ext2fs_get_free_blocks2(fs, group_blk,
138 last_blk, 1, bmap, &new_blk);
139 if (retval)
140 return retval;
141 ext2fs_mark_block_bitmap2(bmap, new_blk);
142 ext2fs_block_bitmap_loc_set(fs, group, new_blk);
143 if (flexbg_size) {
144 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
145 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
146 ext2fs_free_blocks_count_add(fs->super, -1);
147 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
148 ext2fs_group_desc_csum_set(fs, gr);
149 }
150 }
151
152 if (flexbg_size) {
153 blk64_t prev_block = 0;
154 if (group % flexbg_size)
155 prev_block = ext2fs_inode_bitmap_loc(fs, group - 1) + 1;
156 else
157 prev_block = ext2fs_block_bitmap_loc(fs, group) +
158 flexbg_size;
159 start_blk = flexbg_offset(fs, group, prev_block, bmap,
160 rem_grps, 1);
161 last_blk = ext2fs_group_last_block2(fs, last_grp);
162 }
163
164 if (!ext2fs_inode_bitmap_loc(fs, group)) {
165 retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
166 1, bmap, &new_blk);
167 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
168 retval = ext2fs_get_free_blocks2(fs, group_blk,
169 last_blk, 1, bmap, &new_blk);
170 if (retval)
171 return retval;
172 ext2fs_mark_block_bitmap2(bmap, new_blk);
173 ext2fs_inode_bitmap_loc_set(fs, group, new_blk);
174 if (flexbg_size) {
175 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
176 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
177 ext2fs_free_blocks_count_add(fs->super, -1);
178 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
179 ext2fs_group_desc_csum_set(fs, gr);
180 }
181 }
182
183 /*
184 * Allocate the inode table
185 */
186 if (flexbg_size) {
187 blk64_t prev_block = 0;
188
189 if (group % flexbg_size)
190 prev_block = ext2fs_inode_table_loc(fs, group - 1) +
191 fs->inode_blocks_per_group;
192 else
193 prev_block = ext2fs_inode_bitmap_loc(fs, group) +
194 flexbg_size;
195
196 group_blk = flexbg_offset(fs, group, prev_block, bmap,
197 rem_grps, fs->inode_blocks_per_group);
198 last_blk = ext2fs_group_last_block2(fs, last_grp);
199 }
200
201 if (!ext2fs_inode_table_loc(fs, group)) {
202 retval = ext2fs_get_free_blocks2(fs, group_blk, last_blk,
203 fs->inode_blocks_per_group,
204 bmap, &new_blk);
205 if (retval)
206 return retval;
207 for (j=0, blk = new_blk;
208 j < fs->inode_blocks_per_group;
209 j++, blk++) {
210 ext2fs_mark_block_bitmap2(bmap, blk);
211 if (flexbg_size) {
212 dgrp_t gr = ext2fs_group_of_blk2(fs, blk);
213 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
214 ext2fs_free_blocks_count_add(fs->super, -1);
215 ext2fs_bg_flags_clear(fs, gr,
216 EXT2_BG_BLOCK_UNINIT);
217 ext2fs_group_desc_csum_set(fs, gr);
218 }
219 }
220 ext2fs_inode_table_loc_set(fs, group, new_blk);
221 }
222 ext2fs_group_desc_csum_set(fs, group);
223 return 0;
224 }
225
ext2fs_allocate_tables(ext2_filsys fs)226 errcode_t ext2fs_allocate_tables(ext2_filsys fs)
227 {
228 errcode_t retval;
229 dgrp_t i;
230 struct ext2fs_numeric_progress_struct progress;
231
232 ext2fs_numeric_progress_init(fs, &progress, NULL,
233 fs->group_desc_count);
234
235 for (i = 0; i < fs->group_desc_count; i++) {
236 ext2fs_numeric_progress_update(fs, &progress, i);
237 retval = ext2fs_allocate_group_table(fs, i, fs->block_map);
238 if (retval)
239 return retval;
240 }
241 ext2fs_numeric_progress_close(fs, &progress, NULL);
242 return 0;
243 }
244
245