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 "config.h"
14 #include <stdio.h>
15 #include <string.h>
16 #if HAVE_UNISTD_H
17 #include <unistd.h>
18 #endif
19 #include <fcntl.h>
20 #include <time.h>
21 #if HAVE_SYS_STAT_H
22 #include <sys/stat.h>
23 #endif
24 #if HAVE_SYS_TYPES_H
25 #include <sys/types.h>
26 #endif
27
28 #include "ext2_fs.h"
29 #include "ext2fs.h"
30 #include "ext2fsP.h"
31
32 /*
33 * This routine searches for free blocks that can allocate a full
34 * group of bitmaps or inode tables for a flexbg group. Returns the
35 * block number with a correct offset were the bitmaps and inode
36 * tables can be allocated continuously and in order.
37 */
flexbg_offset(ext2_filsys fs,dgrp_t group,blk64_t start_blk,ext2fs_block_bitmap bmap,int rem_grp,int elem_size)38 static blk64_t flexbg_offset(ext2_filsys fs, dgrp_t group, blk64_t start_blk,
39 ext2fs_block_bitmap bmap, int rem_grp,
40 int elem_size)
41 {
42 int flexbg, flexbg_size, size;
43 blk64_t last_blk, first_free = 0;
44 dgrp_t last_grp;
45
46 flexbg_size = 1 << fs->super->s_log_groups_per_flex;
47 flexbg = group / flexbg_size;
48 size = rem_grp * elem_size;
49
50 if (size > (int) (fs->super->s_blocks_per_group / 4))
51 size = (int) fs->super->s_blocks_per_group / 4;
52
53 /*
54 * Don't do a long search if the previous block search is still valid,
55 * but skip minor obstructions such as group descriptor backups.
56 */
57 if (start_blk && start_blk < ext2fs_blocks_count(fs->super) &&
58 ext2fs_get_free_blocks2(fs, start_blk, start_blk + size, elem_size,
59 bmap, &first_free) == 0)
60 return first_free;
61
62 start_blk = ext2fs_group_first_block2(fs, flexbg_size * flexbg);
63 last_grp = group | (flexbg_size - 1);
64 if (last_grp > fs->group_desc_count-1)
65 last_grp = fs->group_desc_count-1;
66 last_blk = ext2fs_group_last_block2(fs, last_grp);
67
68 /* Find the first available block */
69 if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, size,
70 bmap, &first_free) == 0)
71 return first_free;
72
73 if (ext2fs_get_free_blocks2(fs, start_blk, last_blk, elem_size,
74 bmap, &first_free) == 0)
75 return first_free;
76
77 if (ext2fs_get_free_blocks2(fs, 0, last_blk, elem_size, bmap,
78 &first_free) == 0)
79 return first_free;
80
81 return first_free;
82 }
83
ext2fs_allocate_group_table(ext2_filsys fs,dgrp_t group,ext2fs_block_bitmap bmap)84 errcode_t ext2fs_allocate_group_table(ext2_filsys fs, dgrp_t group,
85 ext2fs_block_bitmap bmap)
86 {
87 errcode_t retval;
88 blk64_t group_blk, start_blk, last_blk, new_blk;
89 dgrp_t last_grp = 0;
90 int rem_grps = 0, flexbg_size = 0, table_offset = 0;
91
92 group_blk = ext2fs_group_first_block2(fs, group);
93 last_blk = ext2fs_group_last_block2(fs, group);
94
95 if (!bmap)
96 bmap = fs->block_map;
97
98 if (ext2fs_has_feature_flex_bg(fs->super) &&
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 && !flexbg_size) {
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 table_offset = flexbg_size;
127 if (group % flexbg_size)
128 prev_block = ext2fs_block_bitmap_loc(fs, group - 1) + 1;
129 else if (last_grp == fs->group_desc_count-1) {
130 /*
131 * If we are allocating for the last flex_bg
132 * keep the metadata tables contiguous
133 */
134 table_offset = last_grp & (flexbg_size - 1);
135 if (table_offset == 0)
136 table_offset = flexbg_size;
137 else
138 table_offset++;
139 }
140 /* FIXME: Take backup group descriptor blocks into account
141 * if the flexbg allocations will grow to overlap them... */
142 start_blk = flexbg_offset(fs, group, prev_block, bmap,
143 rem_grps, 1);
144 last_blk = ext2fs_group_last_block2(fs, last_grp);
145 }
146
147 if (!ext2fs_block_bitmap_loc(fs, group)) {
148 retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
149 1, bmap, &new_blk);
150 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
151 retval = ext2fs_get_free_blocks2(fs, group_blk,
152 last_blk, 1, bmap, &new_blk);
153 if (retval)
154 return retval;
155 ext2fs_mark_block_bitmap2(bmap, new_blk);
156 ext2fs_block_bitmap_loc_set(fs, group, new_blk);
157 if (flexbg_size) {
158 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
159 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
160 ext2fs_free_blocks_count_add(fs->super, -1);
161 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
162 ext2fs_group_desc_csum_set(fs, gr);
163 }
164 }
165
166 if (flexbg_size) {
167 blk64_t prev_block = 0;
168 if (group % flexbg_size)
169 prev_block = ext2fs_inode_bitmap_loc(fs, group - 1) + 1;
170 else
171 prev_block = ext2fs_block_bitmap_loc(fs, group) +
172 table_offset;
173 /* FIXME: Take backup group descriptor blocks into account
174 * if the flexbg allocations will grow to overlap them... */
175 start_blk = flexbg_offset(fs, group, prev_block, bmap,
176 rem_grps, 1);
177 last_blk = ext2fs_group_last_block2(fs, last_grp);
178 }
179
180 if (!ext2fs_inode_bitmap_loc(fs, group)) {
181 retval = ext2fs_get_free_blocks2(fs, start_blk, last_blk,
182 1, bmap, &new_blk);
183 if (retval == EXT2_ET_BLOCK_ALLOC_FAIL)
184 retval = ext2fs_get_free_blocks2(fs, group_blk,
185 last_blk, 1, bmap, &new_blk);
186 if (retval)
187 return retval;
188 ext2fs_mark_block_bitmap2(bmap, new_blk);
189 ext2fs_inode_bitmap_loc_set(fs, group, new_blk);
190 if (flexbg_size) {
191 dgrp_t gr = ext2fs_group_of_blk2(fs, new_blk);
192 ext2fs_bg_free_blocks_count_set(fs, gr, ext2fs_bg_free_blocks_count(fs, gr) - 1);
193 ext2fs_free_blocks_count_add(fs->super, -1);
194 ext2fs_bg_flags_clear(fs, gr, EXT2_BG_BLOCK_UNINIT);
195 ext2fs_group_desc_csum_set(fs, gr);
196 }
197 }
198
199 /*
200 * Allocate the inode table
201 */
202 if (flexbg_size) {
203 blk64_t prev_block = 0;
204
205 if (group % flexbg_size)
206 prev_block = ext2fs_inode_table_loc(fs, group - 1) +
207 fs->inode_blocks_per_group;
208 else
209 prev_block = ext2fs_inode_bitmap_loc(fs, group) +
210 table_offset;
211
212 /* FIXME: Take backup group descriptor blocks into account
213 * if the flexbg allocations will grow to overlap them... */
214 group_blk = flexbg_offset(fs, group, prev_block, bmap,
215 rem_grps, fs->inode_blocks_per_group);
216 last_blk = ext2fs_group_last_block2(fs, last_grp);
217 }
218
219 if (!ext2fs_inode_table_loc(fs, group)) {
220 retval = ext2fs_get_free_blocks2(fs, group_blk, last_blk,
221 fs->inode_blocks_per_group,
222 bmap, &new_blk);
223 if (retval)
224 return retval;
225
226 ext2fs_mark_block_bitmap_range2(bmap,
227 new_blk, fs->inode_blocks_per_group);
228 if (flexbg_size) {
229 blk64_t num, blk;
230 num = fs->inode_blocks_per_group;
231 blk = new_blk;
232 while (num) {
233 int gr = ext2fs_group_of_blk2(fs, blk);
234 last_blk = ext2fs_group_last_block2(fs, gr);
235 blk64_t n = num;
236
237 if (blk + num > last_blk)
238 n = last_blk - blk + 1;
239
240 ext2fs_bg_free_blocks_count_set(fs, gr,
241 ext2fs_bg_free_blocks_count(fs, gr) -
242 n/EXT2FS_CLUSTER_RATIO(fs));
243 ext2fs_bg_flags_clear(fs, gr,
244 EXT2_BG_BLOCK_UNINIT);
245 ext2fs_group_desc_csum_set(fs, gr);
246 ext2fs_free_blocks_count_add(fs->super, -n);
247 blk += n;
248 num -= n;
249 }
250 }
251 ext2fs_inode_table_loc_set(fs, group, new_blk);
252 }
253 ext2fs_group_desc_csum_set(fs, group);
254 return 0;
255 }
256
ext2fs_allocate_tables(ext2_filsys fs)257 errcode_t ext2fs_allocate_tables(ext2_filsys fs)
258 {
259 errcode_t retval;
260 dgrp_t i;
261 struct ext2fs_numeric_progress_struct progress;
262
263 if (fs->progress_ops && fs->progress_ops->init)
264 (fs->progress_ops->init)(fs, &progress, NULL,
265 fs->group_desc_count);
266
267 for (i = 0; i < fs->group_desc_count; i++) {
268 if (fs->progress_ops && fs->progress_ops->update)
269 (fs->progress_ops->update)(fs, &progress, i);
270 retval = ext2fs_allocate_group_table(fs, i, fs->block_map);
271 if (retval)
272 return retval;
273 }
274 if (fs->progress_ops && fs->progress_ops->close)
275 (fs->progress_ops->close)(fs, &progress, NULL);
276 return 0;
277 }
278
279