Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/ext3/resize.c | |
3 | * | |
4 | * Support for resizing an ext3 filesystem while it is mounted. | |
5 | * | |
6 | * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com> | |
7 | * | |
8 | * This could probably be made into a module, because it is not often in use. | |
9 | */ | |
10 | ||
1da177e4 LT |
11 | |
12 | #define EXT3FS_DEBUG | |
13 | ||
4613ad18 | 14 | #include "ext3.h" |
1da177e4 LT |
15 | |
16 | ||
17 | #define outside(b, first, last) ((b) < (first) || (b) >= (last)) | |
18 | #define inside(b, first, last) ((b) >= (first) && (b) < (last)) | |
19 | ||
20 | static int verify_group_input(struct super_block *sb, | |
21 | struct ext3_new_group_data *input) | |
22 | { | |
23 | struct ext3_sb_info *sbi = EXT3_SB(sb); | |
24 | struct ext3_super_block *es = sbi->s_es; | |
1c2bf374 MC |
25 | ext3_fsblk_t start = le32_to_cpu(es->s_blocks_count); |
26 | ext3_fsblk_t end = start + input->blocks_count; | |
1da177e4 | 27 | unsigned group = input->group; |
1c2bf374 | 28 | ext3_fsblk_t itend = input->inode_table + sbi->s_itb_per_group; |
1da177e4 LT |
29 | unsigned overhead = ext3_bg_has_super(sb, group) ? |
30 | (1 + ext3_bg_num_gdb(sb, group) + | |
31 | le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; | |
1c2bf374 | 32 | ext3_fsblk_t metaend = start + overhead; |
1da177e4 | 33 | struct buffer_head *bh = NULL; |
1c2bf374 | 34 | ext3_grpblk_t free_blocks_count; |
1da177e4 LT |
35 | int err = -EINVAL; |
36 | ||
37 | input->free_blocks_count = free_blocks_count = | |
38 | input->blocks_count - 2 - overhead - sbi->s_itb_per_group; | |
39 | ||
40 | if (test_opt(sb, DEBUG)) | |
41 | printk(KERN_DEBUG "EXT3-fs: adding %s group %u: %u blocks " | |
42 | "(%d free, %u reserved)\n", | |
43 | ext3_bg_has_super(sb, input->group) ? "normal" : | |
44 | "no-super", input->group, input->blocks_count, | |
45 | free_blocks_count, input->reserved_blocks); | |
46 | ||
47 | if (group != sbi->s_groups_count) | |
e05b6b52 | 48 | ext3_warning(sb, __func__, |
1da177e4 LT |
49 | "Cannot add at group %u (only %lu groups)", |
50 | input->group, sbi->s_groups_count); | |
51 | else if ((start - le32_to_cpu(es->s_first_data_block)) % | |
52 | EXT3_BLOCKS_PER_GROUP(sb)) | |
e05b6b52 | 53 | ext3_warning(sb, __func__, "Last group not full"); |
1da177e4 | 54 | else if (input->reserved_blocks > input->blocks_count / 5) |
e05b6b52 | 55 | ext3_warning(sb, __func__, "Reserved blocks too high (%u)", |
1da177e4 LT |
56 | input->reserved_blocks); |
57 | else if (free_blocks_count < 0) | |
e05b6b52 | 58 | ext3_warning(sb, __func__, "Bad blocks count %u", |
1da177e4 LT |
59 | input->blocks_count); |
60 | else if (!(bh = sb_bread(sb, end - 1))) | |
e05b6b52 | 61 | ext3_warning(sb, __func__, |
1c2bf374 | 62 | "Cannot read last block ("E3FSBLK")", |
1da177e4 LT |
63 | end - 1); |
64 | else if (outside(input->block_bitmap, start, end)) | |
e05b6b52 | 65 | ext3_warning(sb, __func__, |
1da177e4 LT |
66 | "Block bitmap not in group (block %u)", |
67 | input->block_bitmap); | |
68 | else if (outside(input->inode_bitmap, start, end)) | |
e05b6b52 | 69 | ext3_warning(sb, __func__, |
1da177e4 LT |
70 | "Inode bitmap not in group (block %u)", |
71 | input->inode_bitmap); | |
72 | else if (outside(input->inode_table, start, end) || | |
73 | outside(itend - 1, start, end)) | |
e05b6b52 | 74 | ext3_warning(sb, __func__, |
1c2bf374 | 75 | "Inode table not in group (blocks %u-"E3FSBLK")", |
1da177e4 LT |
76 | input->inode_table, itend - 1); |
77 | else if (input->inode_bitmap == input->block_bitmap) | |
e05b6b52 | 78 | ext3_warning(sb, __func__, |
1da177e4 LT |
79 | "Block bitmap same as inode bitmap (%u)", |
80 | input->block_bitmap); | |
81 | else if (inside(input->block_bitmap, input->inode_table, itend)) | |
e05b6b52 | 82 | ext3_warning(sb, __func__, |
1c2bf374 | 83 | "Block bitmap (%u) in inode table (%u-"E3FSBLK")", |
1da177e4 LT |
84 | input->block_bitmap, input->inode_table, itend-1); |
85 | else if (inside(input->inode_bitmap, input->inode_table, itend)) | |
e05b6b52 | 86 | ext3_warning(sb, __func__, |
1c2bf374 | 87 | "Inode bitmap (%u) in inode table (%u-"E3FSBLK")", |
1da177e4 LT |
88 | input->inode_bitmap, input->inode_table, itend-1); |
89 | else if (inside(input->block_bitmap, start, metaend)) | |
e05b6b52 | 90 | ext3_warning(sb, __func__, |
1c2bf374 MC |
91 | "Block bitmap (%u) in GDT table" |
92 | " ("E3FSBLK"-"E3FSBLK")", | |
1da177e4 LT |
93 | input->block_bitmap, start, metaend - 1); |
94 | else if (inside(input->inode_bitmap, start, metaend)) | |
e05b6b52 | 95 | ext3_warning(sb, __func__, |
1c2bf374 MC |
96 | "Inode bitmap (%u) in GDT table" |
97 | " ("E3FSBLK"-"E3FSBLK")", | |
1da177e4 LT |
98 | input->inode_bitmap, start, metaend - 1); |
99 | else if (inside(input->inode_table, start, metaend) || | |
100 | inside(itend - 1, start, metaend)) | |
e05b6b52 | 101 | ext3_warning(sb, __func__, |
1c2bf374 MC |
102 | "Inode table (%u-"E3FSBLK") overlaps" |
103 | "GDT table ("E3FSBLK"-"E3FSBLK")", | |
1da177e4 LT |
104 | input->inode_table, itend - 1, start, metaend - 1); |
105 | else | |
106 | err = 0; | |
107 | brelse(bh); | |
108 | ||
109 | return err; | |
110 | } | |
111 | ||
112 | static struct buffer_head *bclean(handle_t *handle, struct super_block *sb, | |
43d23f90 | 113 | ext3_fsblk_t blk) |
1da177e4 LT |
114 | { |
115 | struct buffer_head *bh; | |
116 | int err; | |
117 | ||
118 | bh = sb_getblk(sb, blk); | |
2973dfdb GOC |
119 | if (!bh) |
120 | return ERR_PTR(-EIO); | |
1da177e4 LT |
121 | if ((err = ext3_journal_get_write_access(handle, bh))) { |
122 | brelse(bh); | |
123 | bh = ERR_PTR(err); | |
124 | } else { | |
125 | lock_buffer(bh); | |
126 | memset(bh->b_data, 0, sb->s_blocksize); | |
127 | set_buffer_uptodate(bh); | |
128 | unlock_buffer(bh); | |
129 | } | |
130 | ||
131 | return bh; | |
132 | } | |
133 | ||
134 | /* | |
135 | * To avoid calling the atomic setbit hundreds or thousands of times, we only | |
136 | * need to use it within a single byte (to ensure we get endianness right). | |
137 | * We can use memset for the rest of the bitmap as there are no other users. | |
138 | */ | |
139 | static void mark_bitmap_end(int start_bit, int end_bit, char *bitmap) | |
140 | { | |
141 | int i; | |
142 | ||
143 | if (start_bit >= end_bit) | |
144 | return; | |
145 | ||
146 | ext3_debug("mark end bits +%d through +%d used\n", start_bit, end_bit); | |
147 | for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++) | |
148 | ext3_set_bit(i, bitmap); | |
149 | if (i < end_bit) | |
150 | memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3); | |
151 | } | |
152 | ||
1ad6ecf9 ES |
153 | /* |
154 | * If we have fewer than thresh credits, extend by EXT3_MAX_TRANS_DATA. | |
155 | * If that fails, restart the transaction & regain write access for the | |
156 | * buffer head which is used for block_bitmap modifications. | |
157 | */ | |
158 | static int extend_or_restart_transaction(handle_t *handle, int thresh, | |
159 | struct buffer_head *bh) | |
160 | { | |
161 | int err; | |
162 | ||
163 | if (handle->h_buffer_credits >= thresh) | |
164 | return 0; | |
165 | ||
166 | err = ext3_journal_extend(handle, EXT3_MAX_TRANS_DATA); | |
167 | if (err < 0) | |
168 | return err; | |
169 | if (err) { | |
170 | err = ext3_journal_restart(handle, EXT3_MAX_TRANS_DATA); | |
171 | if (err) | |
172 | return err; | |
173 | err = ext3_journal_get_write_access(handle, bh); | |
174 | if (err) | |
175 | return err; | |
176 | } | |
177 | ||
178 | return 0; | |
179 | } | |
180 | ||
1da177e4 LT |
181 | /* |
182 | * Set up the block and inode bitmaps, and the inode table for the new group. | |
183 | * This doesn't need to be part of the main transaction, since we are only | |
184 | * changing blocks outside the actual filesystem. We still do journaling to | |
185 | * ensure the recovery is correct in case of a failure just after resize. | |
186 | * If any part of this fails, we simply abort the resize. | |
187 | */ | |
188 | static int setup_new_group_blocks(struct super_block *sb, | |
189 | struct ext3_new_group_data *input) | |
190 | { | |
191 | struct ext3_sb_info *sbi = EXT3_SB(sb); | |
43d23f90 | 192 | ext3_fsblk_t start = ext3_group_first_block_no(sb, input->group); |
1da177e4 LT |
193 | int reserved_gdb = ext3_bg_has_super(sb, input->group) ? |
194 | le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0; | |
195 | unsigned long gdblocks = ext3_bg_num_gdb(sb, input->group); | |
196 | struct buffer_head *bh; | |
197 | handle_t *handle; | |
43d23f90 | 198 | ext3_fsblk_t block; |
1c2bf374 | 199 | ext3_grpblk_t bit; |
1da177e4 LT |
200 | int i; |
201 | int err = 0, err2; | |
202 | ||
1ad6ecf9 ES |
203 | /* This transaction may be extended/restarted along the way */ |
204 | handle = ext3_journal_start_sb(sb, EXT3_MAX_TRANS_DATA); | |
205 | ||
1da177e4 LT |
206 | if (IS_ERR(handle)) |
207 | return PTR_ERR(handle); | |
208 | ||
96d2a495 | 209 | mutex_lock(&sbi->s_resize_lock); |
1da177e4 LT |
210 | if (input->group != sbi->s_groups_count) { |
211 | err = -EBUSY; | |
212 | goto exit_journal; | |
213 | } | |
214 | ||
215 | if (IS_ERR(bh = bclean(handle, sb, input->block_bitmap))) { | |
216 | err = PTR_ERR(bh); | |
217 | goto exit_journal; | |
218 | } | |
219 | ||
220 | if (ext3_bg_has_super(sb, input->group)) { | |
221 | ext3_debug("mark backup superblock %#04lx (+0)\n", start); | |
222 | ext3_set_bit(0, bh->b_data); | |
223 | } | |
224 | ||
225 | /* Copy all of the GDT blocks into the backup in this group */ | |
226 | for (i = 0, bit = 1, block = start + 1; | |
227 | i < gdblocks; i++, block++, bit++) { | |
228 | struct buffer_head *gdb; | |
229 | ||
230 | ext3_debug("update backup group %#04lx (+%d)\n", block, bit); | |
231 | ||
1ad6ecf9 ES |
232 | err = extend_or_restart_transaction(handle, 1, bh); |
233 | if (err) | |
234 | goto exit_bh; | |
235 | ||
1da177e4 | 236 | gdb = sb_getblk(sb, block); |
2973dfdb GOC |
237 | if (!gdb) { |
238 | err = -EIO; | |
239 | goto exit_bh; | |
240 | } | |
1da177e4 LT |
241 | if ((err = ext3_journal_get_write_access(handle, gdb))) { |
242 | brelse(gdb); | |
243 | goto exit_bh; | |
244 | } | |
42a2b6ad ES |
245 | lock_buffer(gdb); |
246 | memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, gdb->b_size); | |
1da177e4 | 247 | set_buffer_uptodate(gdb); |
42a2b6ad | 248 | unlock_buffer(gdb); |
41dc6385 NK |
249 | err = ext3_journal_dirty_metadata(handle, gdb); |
250 | if (err) { | |
251 | brelse(gdb); | |
252 | goto exit_bh; | |
253 | } | |
1da177e4 LT |
254 | ext3_set_bit(bit, bh->b_data); |
255 | brelse(gdb); | |
256 | } | |
257 | ||
258 | /* Zero out all of the reserved backup group descriptor table blocks */ | |
259 | for (i = 0, bit = gdblocks + 1, block = start + bit; | |
260 | i < reserved_gdb; i++, block++, bit++) { | |
261 | struct buffer_head *gdb; | |
262 | ||
263 | ext3_debug("clear reserved block %#04lx (+%d)\n", block, bit); | |
264 | ||
1ad6ecf9 ES |
265 | err = extend_or_restart_transaction(handle, 1, bh); |
266 | if (err) | |
267 | goto exit_bh; | |
268 | ||
1da177e4 | 269 | if (IS_ERR(gdb = bclean(handle, sb, block))) { |
8e0eb401 | 270 | err = PTR_ERR(gdb); |
1da177e4 LT |
271 | goto exit_bh; |
272 | } | |
41dc6385 NK |
273 | err = ext3_journal_dirty_metadata(handle, gdb); |
274 | if (err) { | |
275 | brelse(gdb); | |
276 | goto exit_bh; | |
277 | } | |
1da177e4 LT |
278 | ext3_set_bit(bit, bh->b_data); |
279 | brelse(gdb); | |
280 | } | |
281 | ext3_debug("mark block bitmap %#04x (+%ld)\n", input->block_bitmap, | |
282 | input->block_bitmap - start); | |
283 | ext3_set_bit(input->block_bitmap - start, bh->b_data); | |
284 | ext3_debug("mark inode bitmap %#04x (+%ld)\n", input->inode_bitmap, | |
285 | input->inode_bitmap - start); | |
286 | ext3_set_bit(input->inode_bitmap - start, bh->b_data); | |
287 | ||
288 | /* Zero out all of the inode table blocks */ | |
289 | for (i = 0, block = input->inode_table, bit = block - start; | |
290 | i < sbi->s_itb_per_group; i++, bit++, block++) { | |
291 | struct buffer_head *it; | |
292 | ||
8bdac5d1 | 293 | ext3_debug("clear inode block %#04lx (+%d)\n", block, bit); |
1ad6ecf9 ES |
294 | |
295 | err = extend_or_restart_transaction(handle, 1, bh); | |
296 | if (err) | |
297 | goto exit_bh; | |
298 | ||
1da177e4 LT |
299 | if (IS_ERR(it = bclean(handle, sb, block))) { |
300 | err = PTR_ERR(it); | |
301 | goto exit_bh; | |
302 | } | |
41dc6385 NK |
303 | err = ext3_journal_dirty_metadata(handle, it); |
304 | if (err) { | |
305 | brelse(it); | |
306 | goto exit_bh; | |
307 | } | |
1da177e4 LT |
308 | brelse(it); |
309 | ext3_set_bit(bit, bh->b_data); | |
310 | } | |
1ad6ecf9 ES |
311 | |
312 | err = extend_or_restart_transaction(handle, 2, bh); | |
313 | if (err) | |
314 | goto exit_bh; | |
315 | ||
1da177e4 LT |
316 | mark_bitmap_end(input->blocks_count, EXT3_BLOCKS_PER_GROUP(sb), |
317 | bh->b_data); | |
41dc6385 NK |
318 | err = ext3_journal_dirty_metadata(handle, bh); |
319 | if (err) | |
320 | goto exit_bh; | |
1da177e4 LT |
321 | brelse(bh); |
322 | ||
323 | /* Mark unused entries in inode bitmap used */ | |
324 | ext3_debug("clear inode bitmap %#04x (+%ld)\n", | |
325 | input->inode_bitmap, input->inode_bitmap - start); | |
326 | if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) { | |
327 | err = PTR_ERR(bh); | |
328 | goto exit_journal; | |
329 | } | |
330 | ||
331 | mark_bitmap_end(EXT3_INODES_PER_GROUP(sb), EXT3_BLOCKS_PER_GROUP(sb), | |
332 | bh->b_data); | |
41dc6385 | 333 | err = ext3_journal_dirty_metadata(handle, bh); |
1da177e4 LT |
334 | exit_bh: |
335 | brelse(bh); | |
336 | ||
337 | exit_journal: | |
96d2a495 | 338 | mutex_unlock(&sbi->s_resize_lock); |
1da177e4 LT |
339 | if ((err2 = ext3_journal_stop(handle)) && !err) |
340 | err = err2; | |
341 | ||
342 | return err; | |
343 | } | |
344 | ||
345 | /* | |
346 | * Iterate through the groups which hold BACKUP superblock/GDT copies in an | |
347 | * ext3 filesystem. The counters should be initialized to 1, 5, and 7 before | |
348 | * calling this for the first time. In a sparse filesystem it will be the | |
349 | * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ... | |
350 | * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ... | |
351 | */ | |
352 | static unsigned ext3_list_backups(struct super_block *sb, unsigned *three, | |
353 | unsigned *five, unsigned *seven) | |
354 | { | |
355 | unsigned *min = three; | |
356 | int mult = 3; | |
357 | unsigned ret; | |
358 | ||
359 | if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, | |
360 | EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER)) { | |
361 | ret = *min; | |
362 | *min += 1; | |
363 | return ret; | |
364 | } | |
365 | ||
366 | if (*five < *min) { | |
367 | min = five; | |
368 | mult = 5; | |
369 | } | |
370 | if (*seven < *min) { | |
371 | min = seven; | |
372 | mult = 7; | |
373 | } | |
374 | ||
375 | ret = *min; | |
376 | *min *= mult; | |
377 | ||
378 | return ret; | |
379 | } | |
380 | ||
381 | /* | |
382 | * Check that all of the backup GDT blocks are held in the primary GDT block. | |
383 | * It is assumed that they are stored in group order. Returns the number of | |
384 | * groups in current filesystem that have BACKUPS, or -ve error code. | |
385 | */ | |
386 | static int verify_reserved_gdb(struct super_block *sb, | |
387 | struct buffer_head *primary) | |
388 | { | |
43d23f90 | 389 | const ext3_fsblk_t blk = primary->b_blocknr; |
1da177e4 LT |
390 | const unsigned long end = EXT3_SB(sb)->s_groups_count; |
391 | unsigned three = 1; | |
392 | unsigned five = 5; | |
393 | unsigned seven = 7; | |
394 | unsigned grp; | |
a4e4de36 | 395 | __le32 *p = (__le32 *)primary->b_data; |
1da177e4 LT |
396 | int gdbackups = 0; |
397 | ||
398 | while ((grp = ext3_list_backups(sb, &three, &five, &seven)) < end) { | |
399 | if (le32_to_cpu(*p++) != grp * EXT3_BLOCKS_PER_GROUP(sb) + blk){ | |
e05b6b52 | 400 | ext3_warning(sb, __func__, |
43d23f90 MC |
401 | "reserved GDT "E3FSBLK |
402 | " missing grp %d ("E3FSBLK")", | |
1da177e4 LT |
403 | blk, grp, |
404 | grp * EXT3_BLOCKS_PER_GROUP(sb) + blk); | |
405 | return -EINVAL; | |
406 | } | |
407 | if (++gdbackups > EXT3_ADDR_PER_BLOCK(sb)) | |
408 | return -EFBIG; | |
409 | } | |
410 | ||
411 | return gdbackups; | |
412 | } | |
413 | ||
414 | /* | |
415 | * Called when we need to bring a reserved group descriptor table block into | |
416 | * use from the resize inode. The primary copy of the new GDT block currently | |
417 | * is an indirect block (under the double indirect block in the resize inode). | |
418 | * The new backup GDT blocks will be stored as leaf blocks in this indirect | |
419 | * block, in group order. Even though we know all the block numbers we need, | |
420 | * we check to ensure that the resize inode has actually reserved these blocks. | |
421 | * | |
422 | * Don't need to update the block bitmaps because the blocks are still in use. | |
423 | * | |
424 | * We get all of the error cases out of the way, so that we are sure to not | |
425 | * fail once we start modifying the data on disk, because JBD has no rollback. | |
426 | */ | |
427 | static int add_new_gdb(handle_t *handle, struct inode *inode, | |
428 | struct ext3_new_group_data *input, | |
429 | struct buffer_head **primary) | |
430 | { | |
431 | struct super_block *sb = inode->i_sb; | |
432 | struct ext3_super_block *es = EXT3_SB(sb)->s_es; | |
433 | unsigned long gdb_num = input->group / EXT3_DESC_PER_BLOCK(sb); | |
43d23f90 | 434 | ext3_fsblk_t gdblock = EXT3_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num; |
1da177e4 LT |
435 | struct buffer_head **o_group_desc, **n_group_desc; |
436 | struct buffer_head *dind; | |
437 | int gdbackups; | |
438 | struct ext3_iloc iloc; | |
a4e4de36 | 439 | __le32 *data; |
1da177e4 LT |
440 | int err; |
441 | ||
442 | if (test_opt(sb, DEBUG)) | |
443 | printk(KERN_DEBUG | |
444 | "EXT3-fs: ext3_add_new_gdb: adding group block %lu\n", | |
445 | gdb_num); | |
446 | ||
447 | /* | |
448 | * If we are not using the primary superblock/GDT copy don't resize, | |
449 | * because the user tools have no way of handling this. Probably a | |
450 | * bad time to do it anyways. | |
451 | */ | |
452 | if (EXT3_SB(sb)->s_sbh->b_blocknr != | |
453 | le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block)) { | |
e05b6b52 | 454 | ext3_warning(sb, __func__, |
9f40668d | 455 | "won't resize using backup superblock at %llu", |
1da177e4 LT |
456 | (unsigned long long)EXT3_SB(sb)->s_sbh->b_blocknr); |
457 | return -EPERM; | |
458 | } | |
459 | ||
460 | *primary = sb_bread(sb, gdblock); | |
461 | if (!*primary) | |
462 | return -EIO; | |
463 | ||
464 | if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) { | |
465 | err = gdbackups; | |
466 | goto exit_bh; | |
467 | } | |
468 | ||
469 | data = EXT3_I(inode)->i_data + EXT3_DIND_BLOCK; | |
470 | dind = sb_bread(sb, le32_to_cpu(*data)); | |
471 | if (!dind) { | |
472 | err = -EIO; | |
473 | goto exit_bh; | |
474 | } | |
475 | ||
a4e4de36 | 476 | data = (__le32 *)dind->b_data; |
1da177e4 | 477 | if (le32_to_cpu(data[gdb_num % EXT3_ADDR_PER_BLOCK(sb)]) != gdblock) { |
e05b6b52 | 478 | ext3_warning(sb, __func__, |
43d23f90 | 479 | "new group %u GDT block "E3FSBLK" not reserved", |
1da177e4 LT |
480 | input->group, gdblock); |
481 | err = -EINVAL; | |
482 | goto exit_dind; | |
483 | } | |
484 | ||
485 | if ((err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh))) | |
486 | goto exit_dind; | |
487 | ||
488 | if ((err = ext3_journal_get_write_access(handle, *primary))) | |
489 | goto exit_sbh; | |
490 | ||
491 | if ((err = ext3_journal_get_write_access(handle, dind))) | |
492 | goto exit_primary; | |
493 | ||
494 | /* ext3_reserve_inode_write() gets a reference on the iloc */ | |
495 | if ((err = ext3_reserve_inode_write(handle, inode, &iloc))) | |
496 | goto exit_dindj; | |
497 | ||
f52720ca | 498 | n_group_desc = kmalloc((gdb_num + 1) * sizeof(struct buffer_head *), |
c587f0c0 | 499 | GFP_NOFS); |
1da177e4 LT |
500 | if (!n_group_desc) { |
501 | err = -ENOMEM; | |
e05b6b52 | 502 | ext3_warning (sb, __func__, |
1da177e4 LT |
503 | "not enough memory for %lu groups", gdb_num + 1); |
504 | goto exit_inode; | |
505 | } | |
506 | ||
507 | /* | |
508 | * Finally, we have all of the possible failures behind us... | |
509 | * | |
510 | * Remove new GDT block from inode double-indirect block and clear out | |
511 | * the new GDT block for use (which also "frees" the backup GDT blocks | |
512 | * from the reserved inode). We don't need to change the bitmaps for | |
513 | * these blocks, because they are marked as in-use from being in the | |
514 | * reserved inode, and will become GDT blocks (primary and backup). | |
515 | */ | |
516 | data[gdb_num % EXT3_ADDR_PER_BLOCK(sb)] = 0; | |
41dc6385 NK |
517 | err = ext3_journal_dirty_metadata(handle, dind); |
518 | if (err) | |
519 | goto exit_group_desc; | |
1da177e4 | 520 | brelse(dind); |
41dc6385 | 521 | dind = NULL; |
1da177e4 | 522 | inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9; |
41dc6385 NK |
523 | err = ext3_mark_iloc_dirty(handle, inode, &iloc); |
524 | if (err) | |
525 | goto exit_group_desc; | |
1da177e4 | 526 | memset((*primary)->b_data, 0, sb->s_blocksize); |
41dc6385 NK |
527 | err = ext3_journal_dirty_metadata(handle, *primary); |
528 | if (err) | |
529 | goto exit_group_desc; | |
1da177e4 LT |
530 | |
531 | o_group_desc = EXT3_SB(sb)->s_group_desc; | |
532 | memcpy(n_group_desc, o_group_desc, | |
533 | EXT3_SB(sb)->s_gdb_count * sizeof(struct buffer_head *)); | |
534 | n_group_desc[gdb_num] = *primary; | |
535 | EXT3_SB(sb)->s_group_desc = n_group_desc; | |
536 | EXT3_SB(sb)->s_gdb_count++; | |
537 | kfree(o_group_desc); | |
538 | ||
50e8a289 | 539 | le16_add_cpu(&es->s_reserved_gdt_blocks, -1); |
41dc6385 NK |
540 | err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); |
541 | if (err) | |
542 | goto exit_inode; | |
1da177e4 LT |
543 | |
544 | return 0; | |
545 | ||
41dc6385 NK |
546 | exit_group_desc: |
547 | kfree(n_group_desc); | |
1da177e4 LT |
548 | exit_inode: |
549 | //ext3_journal_release_buffer(handle, iloc.bh); | |
550 | brelse(iloc.bh); | |
551 | exit_dindj: | |
552 | //ext3_journal_release_buffer(handle, dind); | |
553 | exit_primary: | |
554 | //ext3_journal_release_buffer(handle, *primary); | |
555 | exit_sbh: | |
556 | //ext3_journal_release_buffer(handle, *primary); | |
557 | exit_dind: | |
558 | brelse(dind); | |
559 | exit_bh: | |
560 | brelse(*primary); | |
561 | ||
562 | ext3_debug("leaving with error %d\n", err); | |
563 | return err; | |
564 | } | |
565 | ||
566 | /* | |
567 | * Called when we are adding a new group which has a backup copy of each of | |
568 | * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks. | |
569 | * We need to add these reserved backup GDT blocks to the resize inode, so | |
570 | * that they are kept for future resizing and not allocated to files. | |
571 | * | |
572 | * Each reserved backup GDT block will go into a different indirect block. | |
573 | * The indirect blocks are actually the primary reserved GDT blocks, | |
574 | * so we know in advance what their block numbers are. We only get the | |
575 | * double-indirect block to verify it is pointing to the primary reserved | |
576 | * GDT blocks so we don't overwrite a data block by accident. The reserved | |
577 | * backup GDT blocks are stored in their reserved primary GDT block. | |
578 | */ | |
579 | static int reserve_backup_gdb(handle_t *handle, struct inode *inode, | |
580 | struct ext3_new_group_data *input) | |
581 | { | |
582 | struct super_block *sb = inode->i_sb; | |
583 | int reserved_gdb =le16_to_cpu(EXT3_SB(sb)->s_es->s_reserved_gdt_blocks); | |
584 | struct buffer_head **primary; | |
585 | struct buffer_head *dind; | |
586 | struct ext3_iloc iloc; | |
43d23f90 | 587 | ext3_fsblk_t blk; |
a4e4de36 | 588 | __le32 *data, *end; |
1da177e4 LT |
589 | int gdbackups = 0; |
590 | int res, i; | |
591 | int err; | |
592 | ||
c587f0c0 | 593 | primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_NOFS); |
1da177e4 LT |
594 | if (!primary) |
595 | return -ENOMEM; | |
596 | ||
597 | data = EXT3_I(inode)->i_data + EXT3_DIND_BLOCK; | |
598 | dind = sb_bread(sb, le32_to_cpu(*data)); | |
599 | if (!dind) { | |
600 | err = -EIO; | |
601 | goto exit_free; | |
602 | } | |
603 | ||
604 | blk = EXT3_SB(sb)->s_sbh->b_blocknr + 1 + EXT3_SB(sb)->s_gdb_count; | |
9bb91784 JB |
605 | data = (__le32 *)dind->b_data + (EXT3_SB(sb)->s_gdb_count % |
606 | EXT3_ADDR_PER_BLOCK(sb)); | |
a4e4de36 | 607 | end = (__le32 *)dind->b_data + EXT3_ADDR_PER_BLOCK(sb); |
1da177e4 LT |
608 | |
609 | /* Get each reserved primary GDT block and verify it holds backups */ | |
610 | for (res = 0; res < reserved_gdb; res++, blk++) { | |
611 | if (le32_to_cpu(*data) != blk) { | |
e05b6b52 | 612 | ext3_warning(sb, __func__, |
43d23f90 MC |
613 | "reserved block "E3FSBLK |
614 | " not at offset %ld", | |
a4e4de36 DK |
615 | blk, |
616 | (long)(data - (__le32 *)dind->b_data)); | |
1da177e4 LT |
617 | err = -EINVAL; |
618 | goto exit_bh; | |
619 | } | |
620 | primary[res] = sb_bread(sb, blk); | |
621 | if (!primary[res]) { | |
622 | err = -EIO; | |
623 | goto exit_bh; | |
624 | } | |
625 | if ((gdbackups = verify_reserved_gdb(sb, primary[res])) < 0) { | |
626 | brelse(primary[res]); | |
627 | err = gdbackups; | |
628 | goto exit_bh; | |
629 | } | |
630 | if (++data >= end) | |
a4e4de36 | 631 | data = (__le32 *)dind->b_data; |
1da177e4 LT |
632 | } |
633 | ||
634 | for (i = 0; i < reserved_gdb; i++) { | |
635 | if ((err = ext3_journal_get_write_access(handle, primary[i]))) { | |
636 | /* | |
637 | int j; | |
638 | for (j = 0; j < i; j++) | |
639 | ext3_journal_release_buffer(handle, primary[j]); | |
640 | */ | |
641 | goto exit_bh; | |
642 | } | |
643 | } | |
644 | ||
645 | if ((err = ext3_reserve_inode_write(handle, inode, &iloc))) | |
646 | goto exit_bh; | |
647 | ||
648 | /* | |
649 | * Finally we can add each of the reserved backup GDT blocks from | |
650 | * the new group to its reserved primary GDT block. | |
651 | */ | |
652 | blk = input->group * EXT3_BLOCKS_PER_GROUP(sb); | |
653 | for (i = 0; i < reserved_gdb; i++) { | |
654 | int err2; | |
a4e4de36 | 655 | data = (__le32 *)primary[i]->b_data; |
1da177e4 LT |
656 | /* printk("reserving backup %lu[%u] = %lu\n", |
657 | primary[i]->b_blocknr, gdbackups, | |
658 | blk + primary[i]->b_blocknr); */ | |
659 | data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr); | |
660 | err2 = ext3_journal_dirty_metadata(handle, primary[i]); | |
661 | if (!err) | |
662 | err = err2; | |
663 | } | |
664 | inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9; | |
665 | ext3_mark_iloc_dirty(handle, inode, &iloc); | |
666 | ||
667 | exit_bh: | |
668 | while (--res >= 0) | |
669 | brelse(primary[res]); | |
670 | brelse(dind); | |
671 | ||
672 | exit_free: | |
673 | kfree(primary); | |
674 | ||
675 | return err; | |
676 | } | |
677 | ||
678 | /* | |
679 | * Update the backup copies of the ext3 metadata. These don't need to be part | |
680 | * of the main resize transaction, because e2fsck will re-write them if there | |
681 | * is a problem (basically only OOM will cause a problem). However, we | |
682 | * _should_ update the backups if possible, in case the primary gets trashed | |
683 | * for some reason and we need to run e2fsck from a backup superblock. The | |
684 | * important part is that the new block and inode counts are in the backup | |
685 | * superblocks, and the location of the new group metadata in the GDT backups. | |
686 | * | |
96d2a495 ES |
687 | * We do not need take the s_resize_lock for this, because these |
688 | * blocks are not otherwise touched by the filesystem code when it is | |
689 | * mounted. We don't need to worry about last changing from | |
690 | * sbi->s_groups_count, because the worst that can happen is that we | |
691 | * do not copy the full number of backups at this time. The resize | |
692 | * which changed s_groups_count will backup again. | |
1da177e4 LT |
693 | */ |
694 | static void update_backups(struct super_block *sb, | |
695 | int blk_off, char *data, int size) | |
696 | { | |
697 | struct ext3_sb_info *sbi = EXT3_SB(sb); | |
698 | const unsigned long last = sbi->s_groups_count; | |
699 | const int bpg = EXT3_BLOCKS_PER_GROUP(sb); | |
700 | unsigned three = 1; | |
701 | unsigned five = 5; | |
702 | unsigned seven = 7; | |
703 | unsigned group; | |
704 | int rest = sb->s_blocksize - size; | |
705 | handle_t *handle; | |
706 | int err = 0, err2; | |
707 | ||
708 | handle = ext3_journal_start_sb(sb, EXT3_MAX_TRANS_DATA); | |
709 | if (IS_ERR(handle)) { | |
710 | group = 1; | |
711 | err = PTR_ERR(handle); | |
712 | goto exit_err; | |
713 | } | |
714 | ||
715 | while ((group = ext3_list_backups(sb, &three, &five, &seven)) < last) { | |
716 | struct buffer_head *bh; | |
717 | ||
718 | /* Out of journal space, and can't get more - abort - so sad */ | |
719 | if (handle->h_buffer_credits == 0 && | |
720 | ext3_journal_extend(handle, EXT3_MAX_TRANS_DATA) && | |
721 | (err = ext3_journal_restart(handle, EXT3_MAX_TRANS_DATA))) | |
722 | break; | |
723 | ||
724 | bh = sb_getblk(sb, group * bpg + blk_off); | |
2973dfdb GOC |
725 | if (!bh) { |
726 | err = -EIO; | |
727 | break; | |
728 | } | |
8bdac5d1 GOC |
729 | ext3_debug("update metadata backup %#04lx\n", |
730 | (unsigned long)bh->b_blocknr); | |
41dc6385 NK |
731 | if ((err = ext3_journal_get_write_access(handle, bh))) { |
732 | brelse(bh); | |
1da177e4 | 733 | break; |
41dc6385 | 734 | } |
1da177e4 LT |
735 | lock_buffer(bh); |
736 | memcpy(bh->b_data, data, size); | |
737 | if (rest) | |
738 | memset(bh->b_data + size, 0, rest); | |
739 | set_buffer_uptodate(bh); | |
740 | unlock_buffer(bh); | |
41dc6385 | 741 | err = ext3_journal_dirty_metadata(handle, bh); |
1da177e4 | 742 | brelse(bh); |
41dc6385 NK |
743 | if (err) |
744 | break; | |
1da177e4 LT |
745 | } |
746 | if ((err2 = ext3_journal_stop(handle)) && !err) | |
747 | err = err2; | |
748 | ||
749 | /* | |
750 | * Ugh! Need to have e2fsck write the backup copies. It is too | |
751 | * late to revert the resize, we shouldn't fail just because of | |
752 | * the backup copies (they are only needed in case of corruption). | |
753 | * | |
754 | * However, if we got here we have a journal problem too, so we | |
755 | * can't really start a transaction to mark the superblock. | |
756 | * Chicken out and just set the flag on the hope it will be written | |
757 | * to disk, and if not - we will simply wait until next fsck. | |
758 | */ | |
759 | exit_err: | |
760 | if (err) { | |
e05b6b52 | 761 | ext3_warning(sb, __func__, |
1da177e4 | 762 | "can't update backup for group %d (err %d), " |
9f40668d | 763 | "forcing fsck on next reboot", group, err); |
1da177e4 | 764 | sbi->s_mount_state &= ~EXT3_VALID_FS; |
a4e4de36 | 765 | sbi->s_es->s_state &= cpu_to_le16(~EXT3_VALID_FS); |
1da177e4 LT |
766 | mark_buffer_dirty(sbi->s_sbh); |
767 | } | |
768 | } | |
769 | ||
770 | /* Add group descriptor data to an existing or new group descriptor block. | |
771 | * Ensure we handle all possible error conditions _before_ we start modifying | |
772 | * the filesystem, because we cannot abort the transaction and not have it | |
773 | * write the data to disk. | |
774 | * | |
775 | * If we are on a GDT block boundary, we need to get the reserved GDT block. | |
776 | * Otherwise, we may need to add backup GDT blocks for a sparse group. | |
777 | * | |
778 | * We only need to hold the superblock lock while we are actually adding | |
779 | * in the new group's counts to the superblock. Prior to that we have | |
780 | * not really "added" the group at all. We re-check that we are still | |
781 | * adding in the last group in case things have changed since verifying. | |
782 | */ | |
783 | int ext3_group_add(struct super_block *sb, struct ext3_new_group_data *input) | |
784 | { | |
785 | struct ext3_sb_info *sbi = EXT3_SB(sb); | |
786 | struct ext3_super_block *es = sbi->s_es; | |
787 | int reserved_gdb = ext3_bg_has_super(sb, input->group) ? | |
788 | le16_to_cpu(es->s_reserved_gdt_blocks) : 0; | |
789 | struct buffer_head *primary = NULL; | |
790 | struct ext3_group_desc *gdp; | |
791 | struct inode *inode = NULL; | |
792 | handle_t *handle; | |
793 | int gdb_off, gdb_num; | |
794 | int err, err2; | |
795 | ||
796 | gdb_num = input->group / EXT3_DESC_PER_BLOCK(sb); | |
797 | gdb_off = input->group % EXT3_DESC_PER_BLOCK(sb); | |
798 | ||
799 | if (gdb_off == 0 && !EXT3_HAS_RO_COMPAT_FEATURE(sb, | |
800 | EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER)) { | |
e05b6b52 | 801 | ext3_warning(sb, __func__, |
9f40668d | 802 | "Can't resize non-sparse filesystem further"); |
1da177e4 LT |
803 | return -EPERM; |
804 | } | |
805 | ||
32c2d2bc ES |
806 | if (le32_to_cpu(es->s_blocks_count) + input->blocks_count < |
807 | le32_to_cpu(es->s_blocks_count)) { | |
e05b6b52 | 808 | ext3_warning(sb, __func__, "blocks_count overflow\n"); |
32c2d2bc ES |
809 | return -EINVAL; |
810 | } | |
811 | ||
812 | if (le32_to_cpu(es->s_inodes_count) + EXT3_INODES_PER_GROUP(sb) < | |
813 | le32_to_cpu(es->s_inodes_count)) { | |
e05b6b52 | 814 | ext3_warning(sb, __func__, "inodes_count overflow\n"); |
32c2d2bc ES |
815 | return -EINVAL; |
816 | } | |
817 | ||
1da177e4 LT |
818 | if (reserved_gdb || gdb_off == 0) { |
819 | if (!EXT3_HAS_COMPAT_FEATURE(sb, | |
972fbf77 JB |
820 | EXT3_FEATURE_COMPAT_RESIZE_INODE) |
821 | || !le16_to_cpu(es->s_reserved_gdt_blocks)) { | |
e05b6b52 | 822 | ext3_warning(sb, __func__, |
9f40668d | 823 | "No reserved GDT blocks, can't resize"); |
1da177e4 LT |
824 | return -EPERM; |
825 | } | |
473043dc DH |
826 | inode = ext3_iget(sb, EXT3_RESIZE_INO); |
827 | if (IS_ERR(inode)) { | |
e05b6b52 | 828 | ext3_warning(sb, __func__, |
9f40668d | 829 | "Error opening resize inode"); |
473043dc | 830 | return PTR_ERR(inode); |
1da177e4 LT |
831 | } |
832 | } | |
833 | ||
834 | if ((err = verify_group_input(sb, input))) | |
835 | goto exit_put; | |
836 | ||
837 | if ((err = setup_new_group_blocks(sb, input))) | |
838 | goto exit_put; | |
839 | ||
840 | /* | |
841 | * We will always be modifying at least the superblock and a GDT | |
842 | * block. If we are adding a group past the last current GDT block, | |
843 | * we will also modify the inode and the dindirect block. If we | |
844 | * are adding a group with superblock/GDT backups we will also | |
845 | * modify each of the reserved GDT dindirect blocks. | |
846 | */ | |
847 | handle = ext3_journal_start_sb(sb, | |
848 | ext3_bg_has_super(sb, input->group) ? | |
849 | 3 + reserved_gdb : 4); | |
850 | if (IS_ERR(handle)) { | |
851 | err = PTR_ERR(handle); | |
852 | goto exit_put; | |
853 | } | |
854 | ||
96d2a495 | 855 | mutex_lock(&sbi->s_resize_lock); |
29ba1723 | 856 | if (input->group != sbi->s_groups_count) { |
e05b6b52 | 857 | ext3_warning(sb, __func__, |
9f40668d | 858 | "multiple resizers run on filesystem!"); |
aa877b3d | 859 | err = -EBUSY; |
1da177e4 LT |
860 | goto exit_journal; |
861 | } | |
862 | ||
863 | if ((err = ext3_journal_get_write_access(handle, sbi->s_sbh))) | |
864 | goto exit_journal; | |
865 | ||
866 | /* | |
867 | * We will only either add reserved group blocks to a backup group | |
868 | * or remove reserved blocks for the first group in a new group block. | |
869 | * Doing both would be mean more complex code, and sane people don't | |
870 | * use non-sparse filesystems anymore. This is already checked above. | |
871 | */ | |
872 | if (gdb_off) { | |
873 | primary = sbi->s_group_desc[gdb_num]; | |
874 | if ((err = ext3_journal_get_write_access(handle, primary))) | |
875 | goto exit_journal; | |
876 | ||
877 | if (reserved_gdb && ext3_bg_num_gdb(sb, input->group) && | |
878 | (err = reserve_backup_gdb(handle, inode, input))) | |
879 | goto exit_journal; | |
880 | } else if ((err = add_new_gdb(handle, inode, input, &primary))) | |
881 | goto exit_journal; | |
882 | ||
883 | /* | |
884 | * OK, now we've set up the new group. Time to make it active. | |
885 | * | |
96d2a495 | 886 | * We do not lock all allocations via s_resize_lock |
1da177e4 LT |
887 | * so we have to be safe wrt. concurrent accesses the group |
888 | * data. So we need to be careful to set all of the relevant | |
889 | * group descriptor data etc. *before* we enable the group. | |
890 | * | |
29ba1723 | 891 | * The key field here is sbi->s_groups_count: as long as |
1da177e4 LT |
892 | * that retains its old value, nobody is going to access the new |
893 | * group. | |
894 | * | |
895 | * So first we update all the descriptor metadata for the new | |
896 | * group; then we update the total disk blocks count; then we | |
897 | * update the groups count to enable the group; then finally we | |
898 | * update the free space counts so that the system can start | |
899 | * using the new disk blocks. | |
900 | */ | |
901 | ||
902 | /* Update group descriptor block for new group */ | |
903 | gdp = (struct ext3_group_desc *)primary->b_data + gdb_off; | |
904 | ||
905 | gdp->bg_block_bitmap = cpu_to_le32(input->block_bitmap); | |
906 | gdp->bg_inode_bitmap = cpu_to_le32(input->inode_bitmap); | |
907 | gdp->bg_inode_table = cpu_to_le32(input->inode_table); | |
908 | gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count); | |
909 | gdp->bg_free_inodes_count = cpu_to_le16(EXT3_INODES_PER_GROUP(sb)); | |
910 | ||
911 | /* | |
912 | * Make the new blocks and inodes valid next. We do this before | |
913 | * increasing the group count so that once the group is enabled, | |
914 | * all of its blocks and inodes are already valid. | |
915 | * | |
916 | * We always allocate group-by-group, then block-by-block or | |
917 | * inode-by-inode within a group, so enabling these | |
918 | * blocks/inodes before the group is live won't actually let us | |
919 | * allocate the new space yet. | |
920 | */ | |
50e8a289 MS |
921 | le32_add_cpu(&es->s_blocks_count, input->blocks_count); |
922 | le32_add_cpu(&es->s_inodes_count, EXT3_INODES_PER_GROUP(sb)); | |
1da177e4 LT |
923 | |
924 | /* | |
925 | * We need to protect s_groups_count against other CPUs seeing | |
926 | * inconsistent state in the superblock. | |
927 | * | |
928 | * The precise rules we use are: | |
929 | * | |
96d2a495 | 930 | * * Writers of s_groups_count *must* hold s_resize_lock |
1da177e4 LT |
931 | * AND |
932 | * * Writers must perform a smp_wmb() after updating all dependent | |
933 | * data and before modifying the groups count | |
934 | * | |
96d2a495 | 935 | * * Readers must hold s_resize_lock over the access |
1da177e4 LT |
936 | * OR |
937 | * * Readers must perform an smp_rmb() after reading the groups count | |
938 | * and before reading any dependent data. | |
939 | * | |
940 | * NB. These rules can be relaxed when checking the group count | |
941 | * while freeing data, as we can only allocate from a block | |
942 | * group after serialising against the group count, and we can | |
943 | * only then free after serialising in turn against that | |
944 | * allocation. | |
945 | */ | |
946 | smp_wmb(); | |
947 | ||
948 | /* Update the global fs size fields */ | |
29ba1723 | 949 | sbi->s_groups_count++; |
1da177e4 | 950 | |
41dc6385 NK |
951 | err = ext3_journal_dirty_metadata(handle, primary); |
952 | if (err) | |
953 | goto exit_journal; | |
1da177e4 LT |
954 | |
955 | /* Update the reserved block counts only once the new group is | |
956 | * active. */ | |
50e8a289 | 957 | le32_add_cpu(&es->s_r_blocks_count, input->reserved_blocks); |
1da177e4 LT |
958 | |
959 | /* Update the free space counts */ | |
aa0dff2d | 960 | percpu_counter_add(&sbi->s_freeblocks_counter, |
1da177e4 | 961 | input->free_blocks_count); |
aa0dff2d | 962 | percpu_counter_add(&sbi->s_freeinodes_counter, |
1da177e4 LT |
963 | EXT3_INODES_PER_GROUP(sb)); |
964 | ||
41dc6385 | 965 | err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); |
1da177e4 LT |
966 | |
967 | exit_journal: | |
96d2a495 | 968 | mutex_unlock(&sbi->s_resize_lock); |
1da177e4 LT |
969 | if ((err2 = ext3_journal_stop(handle)) && !err) |
970 | err = err2; | |
971 | if (!err) { | |
972 | update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, | |
973 | sizeof(struct ext3_super_block)); | |
974 | update_backups(sb, primary->b_blocknr, primary->b_data, | |
975 | primary->b_size); | |
976 | } | |
977 | exit_put: | |
978 | iput(inode); | |
979 | return err; | |
980 | } /* ext3_group_add */ | |
981 | ||
982 | /* Extend the filesystem to the new number of blocks specified. This entry | |
983 | * point is only used to extend the current filesystem to the end of the last | |
984 | * existing group. It can be accessed via ioctl, or by "remount,resize=<size>" | |
985 | * for emergencies (because it has no dependencies on reserved blocks). | |
986 | * | |
987 | * If we _really_ wanted, we could use default values to call ext3_group_add() | |
988 | * allow the "remount" trick to work for arbitrary resizing, assuming enough | |
989 | * GDT blocks are reserved to grow to the desired size. | |
990 | */ | |
991 | int ext3_group_extend(struct super_block *sb, struct ext3_super_block *es, | |
43d23f90 | 992 | ext3_fsblk_t n_blocks_count) |
1da177e4 | 993 | { |
43d23f90 | 994 | ext3_fsblk_t o_blocks_count; |
1c2bf374 MC |
995 | ext3_grpblk_t last; |
996 | ext3_grpblk_t add; | |
1da177e4 LT |
997 | struct buffer_head * bh; |
998 | handle_t *handle; | |
1c2bf374 MC |
999 | int err; |
1000 | unsigned long freed_blocks; | |
1da177e4 LT |
1001 | |
1002 | /* We don't need to worry about locking wrt other resizers just | |
1003 | * yet: we're going to revalidate es->s_blocks_count after | |
96d2a495 | 1004 | * taking the s_resize_lock below. */ |
1da177e4 | 1005 | o_blocks_count = le32_to_cpu(es->s_blocks_count); |
1da177e4 LT |
1006 | |
1007 | if (test_opt(sb, DEBUG)) | |
db50d20b | 1008 | printk(KERN_DEBUG "EXT3-fs: extending last group from "E3FSBLK |
25985edc | 1009 | " up to "E3FSBLK" blocks\n", |
1da177e4 LT |
1010 | o_blocks_count, n_blocks_count); |
1011 | ||
1012 | if (n_blocks_count == 0 || n_blocks_count == o_blocks_count) | |
1013 | return 0; | |
1014 | ||
fcd5df35 MC |
1015 | if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) { |
1016 | printk(KERN_ERR "EXT3-fs: filesystem on %s:" | |
db50d20b | 1017 | " too large to resize to "E3FSBLK" blocks safely\n", |
fcd5df35 MC |
1018 | sb->s_id, n_blocks_count); |
1019 | if (sizeof(sector_t) < 8) | |
e05b6b52 | 1020 | ext3_warning(sb, __func__, |
90c699a9 | 1021 | "CONFIG_LBDAF not enabled\n"); |
fcd5df35 MC |
1022 | return -EINVAL; |
1023 | } | |
1024 | ||
1da177e4 | 1025 | if (n_blocks_count < o_blocks_count) { |
e05b6b52 | 1026 | ext3_warning(sb, __func__, |
1da177e4 LT |
1027 | "can't shrink FS - resize aborted"); |
1028 | return -EBUSY; | |
1029 | } | |
1030 | ||
1031 | /* Handle the remaining blocks in the last group only. */ | |
1032 | last = (o_blocks_count - le32_to_cpu(es->s_first_data_block)) % | |
1033 | EXT3_BLOCKS_PER_GROUP(sb); | |
1034 | ||
1035 | if (last == 0) { | |
e05b6b52 | 1036 | ext3_warning(sb, __func__, |
9f40668d | 1037 | "need to use ext2online to resize further"); |
1da177e4 LT |
1038 | return -EPERM; |
1039 | } | |
1040 | ||
1041 | add = EXT3_BLOCKS_PER_GROUP(sb) - last; | |
1042 | ||
32c2d2bc | 1043 | if (o_blocks_count + add < o_blocks_count) { |
e05b6b52 | 1044 | ext3_warning(sb, __func__, "blocks_count overflow"); |
32c2d2bc ES |
1045 | return -EINVAL; |
1046 | } | |
1047 | ||
1da177e4 LT |
1048 | if (o_blocks_count + add > n_blocks_count) |
1049 | add = n_blocks_count - o_blocks_count; | |
1050 | ||
1051 | if (o_blocks_count + add < n_blocks_count) | |
e05b6b52 | 1052 | ext3_warning(sb, __func__, |
43d23f90 MC |
1053 | "will only finish group ("E3FSBLK |
1054 | " blocks, %u new)", | |
1da177e4 LT |
1055 | o_blocks_count + add, add); |
1056 | ||
1057 | /* See if the device is actually as big as what was requested */ | |
1058 | bh = sb_bread(sb, o_blocks_count + add -1); | |
1059 | if (!bh) { | |
e05b6b52 | 1060 | ext3_warning(sb, __func__, |
1da177e4 LT |
1061 | "can't read last block, resize aborted"); |
1062 | return -ENOSPC; | |
1063 | } | |
1064 | brelse(bh); | |
1065 | ||
1066 | /* We will update the superblock, one block bitmap, and | |
1067 | * one group descriptor via ext3_free_blocks(). | |
1068 | */ | |
1069 | handle = ext3_journal_start_sb(sb, 3); | |
1070 | if (IS_ERR(handle)) { | |
1071 | err = PTR_ERR(handle); | |
e05b6b52 | 1072 | ext3_warning(sb, __func__, "error %d on journal start",err); |
1da177e4 LT |
1073 | goto exit_put; |
1074 | } | |
1075 | ||
96d2a495 | 1076 | mutex_lock(&EXT3_SB(sb)->s_resize_lock); |
1da177e4 | 1077 | if (o_blocks_count != le32_to_cpu(es->s_blocks_count)) { |
e05b6b52 | 1078 | ext3_warning(sb, __func__, |
9f40668d | 1079 | "multiple resizers run on filesystem!"); |
96d2a495 | 1080 | mutex_unlock(&EXT3_SB(sb)->s_resize_lock); |
22a5daf5 | 1081 | ext3_journal_stop(handle); |
1da177e4 LT |
1082 | err = -EBUSY; |
1083 | goto exit_put; | |
1084 | } | |
1085 | ||
1086 | if ((err = ext3_journal_get_write_access(handle, | |
1087 | EXT3_SB(sb)->s_sbh))) { | |
e05b6b52 | 1088 | ext3_warning(sb, __func__, |
1da177e4 | 1089 | "error %d on journal write access", err); |
96d2a495 | 1090 | mutex_unlock(&EXT3_SB(sb)->s_resize_lock); |
1da177e4 LT |
1091 | ext3_journal_stop(handle); |
1092 | goto exit_put; | |
1093 | } | |
1094 | es->s_blocks_count = cpu_to_le32(o_blocks_count + add); | |
41dc6385 | 1095 | err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); |
96d2a495 | 1096 | mutex_unlock(&EXT3_SB(sb)->s_resize_lock); |
41dc6385 NK |
1097 | if (err) { |
1098 | ext3_warning(sb, __func__, | |
1099 | "error %d on journal dirty metadata", err); | |
1100 | ext3_journal_stop(handle); | |
1101 | goto exit_put; | |
1102 | } | |
db50d20b NK |
1103 | ext3_debug("freeing blocks "E3FSBLK" through "E3FSBLK"\n", |
1104 | o_blocks_count, o_blocks_count + add); | |
1da177e4 | 1105 | ext3_free_blocks_sb(handle, sb, o_blocks_count, add, &freed_blocks); |
db50d20b NK |
1106 | ext3_debug("freed blocks "E3FSBLK" through "E3FSBLK"\n", |
1107 | o_blocks_count, o_blocks_count + add); | |
1da177e4 LT |
1108 | if ((err = ext3_journal_stop(handle))) |
1109 | goto exit_put; | |
1110 | if (test_opt(sb, DEBUG)) | |
1111 | printk(KERN_DEBUG "EXT3-fs: extended group to %u blocks\n", | |
1112 | le32_to_cpu(es->s_blocks_count)); | |
1113 | update_backups(sb, EXT3_SB(sb)->s_sbh->b_blocknr, (char *)es, | |
1114 | sizeof(struct ext3_super_block)); | |
1115 | exit_put: | |
1116 | return err; | |
1117 | } /* ext3_group_extend */ |