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1/*
2 * Copyright IBM Corporation, 2007
3 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of version 2.1 of the GNU Lesser General Public License
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
12 *
13 */
14
15#include <linux/slab.h>
16#include "ext4_jbd2.h"
17
18/*
19 * The contiguous blocks details which can be
20 * represented by a single extent
21 */
22struct migrate_struct {
23 ext4_lblk_t first_block, last_block, curr_block;
24 ext4_fsblk_t first_pblock, last_pblock;
25};
26
27static int finish_range(handle_t *handle, struct inode *inode,
28 struct migrate_struct *lb)
29
30{
31 int retval = 0, needed;
32 struct ext4_extent newext;
33 struct ext4_ext_path *path;
34 if (lb->first_pblock == 0)
35 return 0;
36
37 /* Add the extent to temp inode*/
38 newext.ee_block = cpu_to_le32(lb->first_block);
39 newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
40 ext4_ext_store_pblock(&newext, lb->first_pblock);
41 path = ext4_ext_find_extent(inode, lb->first_block, NULL);
42
43 if (IS_ERR(path)) {
44 retval = PTR_ERR(path);
45 path = NULL;
46 goto err_out;
47 }
48
49 /*
50 * Calculate the credit needed to inserting this extent
51 * Since we are doing this in loop we may accumalate extra
52 * credit. But below we try to not accumalate too much
53 * of them by restarting the journal.
54 */
55 needed = ext4_ext_calc_credits_for_single_extent(inode,
56 lb->last_block - lb->first_block + 1, path);
57
58 /*
59 * Make sure the credit we accumalated is not really high
60 */
61 if (needed && ext4_handle_has_enough_credits(handle,
62 EXT4_RESERVE_TRANS_BLOCKS)) {
63 retval = ext4_journal_restart(handle, needed);
64 if (retval)
65 goto err_out;
66 } else if (needed) {
67 retval = ext4_journal_extend(handle, needed);
68 if (retval) {
69 /*
70 * IF not able to extend the journal restart the journal
71 */
72 retval = ext4_journal_restart(handle, needed);
73 if (retval)
74 goto err_out;
75 }
76 }
77 retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
78err_out:
79 if (path) {
80 ext4_ext_drop_refs(path);
81 kfree(path);
82 }
83 lb->first_pblock = 0;
84 return retval;
85}
86
87static int update_extent_range(handle_t *handle, struct inode *inode,
88 ext4_fsblk_t pblock, struct migrate_struct *lb)
89{
90 int retval;
91 /*
92 * See if we can add on to the existing range (if it exists)
93 */
94 if (lb->first_pblock &&
95 (lb->last_pblock+1 == pblock) &&
96 (lb->last_block+1 == lb->curr_block)) {
97 lb->last_pblock = pblock;
98 lb->last_block = lb->curr_block;
99 lb->curr_block++;
100 return 0;
101 }
102 /*
103 * Start a new range.
104 */
105 retval = finish_range(handle, inode, lb);
106 lb->first_pblock = lb->last_pblock = pblock;
107 lb->first_block = lb->last_block = lb->curr_block;
108 lb->curr_block++;
109 return retval;
110}
111
112static int update_ind_extent_range(handle_t *handle, struct inode *inode,
113 ext4_fsblk_t pblock,
114 struct migrate_struct *lb)
115{
116 struct buffer_head *bh;
117 __le32 *i_data;
118 int i, retval = 0;
119 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
120
121 bh = sb_bread(inode->i_sb, pblock);
122 if (!bh)
123 return -EIO;
124
125 i_data = (__le32 *)bh->b_data;
126 for (i = 0; i < max_entries; i++) {
127 if (i_data[i]) {
128 retval = update_extent_range(handle, inode,
129 le32_to_cpu(i_data[i]), lb);
130 if (retval)
131 break;
132 } else {
133 lb->curr_block++;
134 }
135 }
136 put_bh(bh);
137 return retval;
138
139}
140
141static int update_dind_extent_range(handle_t *handle, struct inode *inode,
142 ext4_fsblk_t pblock,
143 struct migrate_struct *lb)
144{
145 struct buffer_head *bh;
146 __le32 *i_data;
147 int i, retval = 0;
148 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
149
150 bh = sb_bread(inode->i_sb, pblock);
151 if (!bh)
152 return -EIO;
153
154 i_data = (__le32 *)bh->b_data;
155 for (i = 0; i < max_entries; i++) {
156 if (i_data[i]) {
157 retval = update_ind_extent_range(handle, inode,
158 le32_to_cpu(i_data[i]), lb);
159 if (retval)
160 break;
161 } else {
162 /* Only update the file block number */
163 lb->curr_block += max_entries;
164 }
165 }
166 put_bh(bh);
167 return retval;
168
169}
170
171static int update_tind_extent_range(handle_t *handle, struct inode *inode,
172 ext4_fsblk_t pblock,
173 struct migrate_struct *lb)
174{
175 struct buffer_head *bh;
176 __le32 *i_data;
177 int i, retval = 0;
178 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
179
180 bh = sb_bread(inode->i_sb, pblock);
181 if (!bh)
182 return -EIO;
183
184 i_data = (__le32 *)bh->b_data;
185 for (i = 0; i < max_entries; i++) {
186 if (i_data[i]) {
187 retval = update_dind_extent_range(handle, inode,
188 le32_to_cpu(i_data[i]), lb);
189 if (retval)
190 break;
191 } else {
192 /* Only update the file block number */
193 lb->curr_block += max_entries * max_entries;
194 }
195 }
196 put_bh(bh);
197 return retval;
198
199}
200
201static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
202{
203 int retval = 0, needed;
204
205 if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
206 return 0;
207 /*
208 * We are freeing a blocks. During this we touch
209 * superblock, group descriptor and block bitmap.
210 * So allocate a credit of 3. We may update
211 * quota (user and group).
212 */
213 needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
214
215 if (ext4_journal_extend(handle, needed) != 0)
216 retval = ext4_journal_restart(handle, needed);
217
218 return retval;
219}
220
221static int free_dind_blocks(handle_t *handle,
222 struct inode *inode, __le32 i_data)
223{
224 int i;
225 __le32 *tmp_idata;
226 struct buffer_head *bh;
227 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
228
229 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
230 if (!bh)
231 return -EIO;
232
233 tmp_idata = (__le32 *)bh->b_data;
234 for (i = 0; i < max_entries; i++) {
235 if (tmp_idata[i]) {
236 extend_credit_for_blkdel(handle, inode);
237 ext4_free_blocks(handle, inode, NULL,
238 le32_to_cpu(tmp_idata[i]), 1,
239 EXT4_FREE_BLOCKS_METADATA |
240 EXT4_FREE_BLOCKS_FORGET);
241 }
242 }
243 put_bh(bh);
244 extend_credit_for_blkdel(handle, inode);
245 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
246 EXT4_FREE_BLOCKS_METADATA |
247 EXT4_FREE_BLOCKS_FORGET);
248 return 0;
249}
250
251static int free_tind_blocks(handle_t *handle,
252 struct inode *inode, __le32 i_data)
253{
254 int i, retval = 0;
255 __le32 *tmp_idata;
256 struct buffer_head *bh;
257 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
258
259 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
260 if (!bh)
261 return -EIO;
262
263 tmp_idata = (__le32 *)bh->b_data;
264 for (i = 0; i < max_entries; i++) {
265 if (tmp_idata[i]) {
266 retval = free_dind_blocks(handle,
267 inode, tmp_idata[i]);
268 if (retval) {
269 put_bh(bh);
270 return retval;
271 }
272 }
273 }
274 put_bh(bh);
275 extend_credit_for_blkdel(handle, inode);
276 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
277 EXT4_FREE_BLOCKS_METADATA |
278 EXT4_FREE_BLOCKS_FORGET);
279 return 0;
280}
281
282static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
283{
284 int retval;
285
286 /* ei->i_data[EXT4_IND_BLOCK] */
287 if (i_data[0]) {
288 extend_credit_for_blkdel(handle, inode);
289 ext4_free_blocks(handle, inode, NULL,
290 le32_to_cpu(i_data[0]), 1,
291 EXT4_FREE_BLOCKS_METADATA |
292 EXT4_FREE_BLOCKS_FORGET);
293 }
294
295 /* ei->i_data[EXT4_DIND_BLOCK] */
296 if (i_data[1]) {
297 retval = free_dind_blocks(handle, inode, i_data[1]);
298 if (retval)
299 return retval;
300 }
301
302 /* ei->i_data[EXT4_TIND_BLOCK] */
303 if (i_data[2]) {
304 retval = free_tind_blocks(handle, inode, i_data[2]);
305 if (retval)
306 return retval;
307 }
308 return 0;
309}
310
311static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
312 struct inode *tmp_inode)
313{
314 int retval;
315 __le32 i_data[3];
316 struct ext4_inode_info *ei = EXT4_I(inode);
317 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
318
319 /*
320 * One credit accounted for writing the
321 * i_data field of the original inode
322 */
323 retval = ext4_journal_extend(handle, 1);
324 if (retval) {
325 retval = ext4_journal_restart(handle, 1);
326 if (retval)
327 goto err_out;
328 }
329
330 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
331 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
332 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
333
334 down_write(&EXT4_I(inode)->i_data_sem);
335 /*
336 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
337 * happened after we started the migrate. We need to
338 * fail the migrate
339 */
340 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
341 retval = -EAGAIN;
342 up_write(&EXT4_I(inode)->i_data_sem);
343 goto err_out;
344 } else
345 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
346 /*
347 * We have the extent map build with the tmp inode.
348 * Now copy the i_data across
349 */
350 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
351 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
352
353 /*
354 * Update i_blocks with the new blocks that got
355 * allocated while adding extents for extent index
356 * blocks.
357 *
358 * While converting to extents we need not
359 * update the orignal inode i_blocks for extent blocks
360 * via quota APIs. The quota update happened via tmp_inode already.
361 */
362 spin_lock(&inode->i_lock);
363 inode->i_blocks += tmp_inode->i_blocks;
364 spin_unlock(&inode->i_lock);
365 up_write(&EXT4_I(inode)->i_data_sem);
366
367 /*
368 * We mark the inode dirty after, because we decrement the
369 * i_blocks when freeing the indirect meta-data blocks
370 */
371 retval = free_ind_block(handle, inode, i_data);
372 ext4_mark_inode_dirty(handle, inode);
373
374err_out:
375 return retval;
376}
377
378static int free_ext_idx(handle_t *handle, struct inode *inode,
379 struct ext4_extent_idx *ix)
380{
381 int i, retval = 0;
382 ext4_fsblk_t block;
383 struct buffer_head *bh;
384 struct ext4_extent_header *eh;
385
386 block = ext4_idx_pblock(ix);
387 bh = sb_bread(inode->i_sb, block);
388 if (!bh)
389 return -EIO;
390
391 eh = (struct ext4_extent_header *)bh->b_data;
392 if (eh->eh_depth != 0) {
393 ix = EXT_FIRST_INDEX(eh);
394 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
395 retval = free_ext_idx(handle, inode, ix);
396 if (retval)
397 break;
398 }
399 }
400 put_bh(bh);
401 extend_credit_for_blkdel(handle, inode);
402 ext4_free_blocks(handle, inode, NULL, block, 1,
403 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
404 return retval;
405}
406
407/*
408 * Free the extent meta data blocks only
409 */
410static int free_ext_block(handle_t *handle, struct inode *inode)
411{
412 int i, retval = 0;
413 struct ext4_inode_info *ei = EXT4_I(inode);
414 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
415 struct ext4_extent_idx *ix;
416 if (eh->eh_depth == 0)
417 /*
418 * No extra blocks allocated for extent meta data
419 */
420 return 0;
421 ix = EXT_FIRST_INDEX(eh);
422 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
423 retval = free_ext_idx(handle, inode, ix);
424 if (retval)
425 return retval;
426 }
427 return retval;
428
429}
430
431int ext4_ext_migrate(struct inode *inode)
432{
433 handle_t *handle;
434 int retval = 0, i;
435 __le32 *i_data;
436 struct ext4_inode_info *ei;
437 struct inode *tmp_inode = NULL;
438 struct migrate_struct lb;
439 unsigned long max_entries;
440 __u32 goal;
441 uid_t owner[2];
442
443 /*
444 * If the filesystem does not support extents, or the inode
445 * already is extent-based, error out.
446 */
447 if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
448 EXT4_FEATURE_INCOMPAT_EXTENTS) ||
449 (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
450 return -EINVAL;
451
452 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
453 /*
454 * don't migrate fast symlink
455 */
456 return retval;
457
458 handle = ext4_journal_start(inode,
459 EXT4_DATA_TRANS_BLOCKS(inode->i_sb) +
460 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
461 EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)
462 + 1);
463 if (IS_ERR(handle)) {
464 retval = PTR_ERR(handle);
465 return retval;
466 }
467 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
468 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
469 owner[0] = i_uid_read(inode);
470 owner[1] = i_gid_read(inode);
471 tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
472 S_IFREG, NULL, goal, owner);
473 if (IS_ERR(tmp_inode)) {
474 retval = PTR_ERR(tmp_inode);
475 ext4_journal_stop(handle);
476 return retval;
477 }
478 i_size_write(tmp_inode, i_size_read(inode));
479 /*
480 * Set the i_nlink to zero so it will be deleted later
481 * when we drop inode reference.
482 */
483 clear_nlink(tmp_inode);
484
485 ext4_ext_tree_init(handle, tmp_inode);
486 ext4_orphan_add(handle, tmp_inode);
487 ext4_journal_stop(handle);
488
489 /*
490 * start with one credit accounted for
491 * superblock modification.
492 *
493 * For the tmp_inode we already have committed the
494 * trascation that created the inode. Later as and
495 * when we add extents we extent the journal
496 */
497 /*
498 * Even though we take i_mutex we can still cause block
499 * allocation via mmap write to holes. If we have allocated
500 * new blocks we fail migrate. New block allocation will
501 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
502 * with i_data_sem held to prevent racing with block
503 * allocation.
504 */
505 down_read((&EXT4_I(inode)->i_data_sem));
506 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
507 up_read((&EXT4_I(inode)->i_data_sem));
508
509 handle = ext4_journal_start(inode, 1);
510 if (IS_ERR(handle)) {
511 /*
512 * It is impossible to update on-disk structures without
513 * a handle, so just rollback in-core changes and live other
514 * work to orphan_list_cleanup()
515 */
516 ext4_orphan_del(NULL, tmp_inode);
517 retval = PTR_ERR(handle);
518 goto out;
519 }
520
521 ei = EXT4_I(inode);
522 i_data = ei->i_data;
523 memset(&lb, 0, sizeof(lb));
524
525 /* 32 bit block address 4 bytes */
526 max_entries = inode->i_sb->s_blocksize >> 2;
527 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
528 if (i_data[i]) {
529 retval = update_extent_range(handle, tmp_inode,
530 le32_to_cpu(i_data[i]), &lb);
531 if (retval)
532 goto err_out;
533 } else
534 lb.curr_block++;
535 }
536 if (i_data[EXT4_IND_BLOCK]) {
537 retval = update_ind_extent_range(handle, tmp_inode,
538 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
539 if (retval)
540 goto err_out;
541 } else
542 lb.curr_block += max_entries;
543 if (i_data[EXT4_DIND_BLOCK]) {
544 retval = update_dind_extent_range(handle, tmp_inode,
545 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
546 if (retval)
547 goto err_out;
548 } else
549 lb.curr_block += max_entries * max_entries;
550 if (i_data[EXT4_TIND_BLOCK]) {
551 retval = update_tind_extent_range(handle, tmp_inode,
552 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
553 if (retval)
554 goto err_out;
555 }
556 /*
557 * Build the last extent
558 */
559 retval = finish_range(handle, tmp_inode, &lb);
560err_out:
561 if (retval)
562 /*
563 * Failure case delete the extent information with the
564 * tmp_inode
565 */
566 free_ext_block(handle, tmp_inode);
567 else {
568 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
569 if (retval)
570 /*
571 * if we fail to swap inode data free the extent
572 * details of the tmp inode
573 */
574 free_ext_block(handle, tmp_inode);
575 }
576
577 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
578 if (ext4_journal_extend(handle, 1) != 0)
579 ext4_journal_restart(handle, 1);
580
581 /*
582 * Mark the tmp_inode as of size zero
583 */
584 i_size_write(tmp_inode, 0);
585
586 /*
587 * set the i_blocks count to zero
588 * so that the ext4_delete_inode does the
589 * right job
590 *
591 * We don't need to take the i_lock because
592 * the inode is not visible to user space.
593 */
594 tmp_inode->i_blocks = 0;
595
596 /* Reset the extent details */
597 ext4_ext_tree_init(handle, tmp_inode);
598 ext4_journal_stop(handle);
599out:
600 unlock_new_inode(tmp_inode);
601 iput(tmp_inode);
602
603 return retval;
604}
1// SPDX-License-Identifier: LGPL-2.1
2/*
3 * Copyright IBM Corporation, 2007
4 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
5 *
6 */
7
8#include <linux/slab.h>
9#include "ext4_jbd2.h"
10#include "ext4_extents.h"
11
12/*
13 * The contiguous blocks details which can be
14 * represented by a single extent
15 */
16struct migrate_struct {
17 ext4_lblk_t first_block, last_block, curr_block;
18 ext4_fsblk_t first_pblock, last_pblock;
19};
20
21static int finish_range(handle_t *handle, struct inode *inode,
22 struct migrate_struct *lb)
23
24{
25 int retval = 0, needed;
26 struct ext4_extent newext;
27 struct ext4_ext_path *path;
28 if (lb->first_pblock == 0)
29 return 0;
30
31 /* Add the extent to temp inode*/
32 newext.ee_block = cpu_to_le32(lb->first_block);
33 newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
34 ext4_ext_store_pblock(&newext, lb->first_pblock);
35 /* Locking only for convinience since we are operating on temp inode */
36 down_write(&EXT4_I(inode)->i_data_sem);
37 path = ext4_find_extent(inode, lb->first_block, NULL, 0);
38 if (IS_ERR(path)) {
39 retval = PTR_ERR(path);
40 path = NULL;
41 goto err_out;
42 }
43
44 /*
45 * Calculate the credit needed to inserting this extent
46 * Since we are doing this in loop we may accumalate extra
47 * credit. But below we try to not accumalate too much
48 * of them by restarting the journal.
49 */
50 needed = ext4_ext_calc_credits_for_single_extent(inode,
51 lb->last_block - lb->first_block + 1, path);
52
53 /*
54 * Make sure the credit we accumalated is not really high
55 */
56 if (needed && ext4_handle_has_enough_credits(handle,
57 EXT4_RESERVE_TRANS_BLOCKS)) {
58 up_write((&EXT4_I(inode)->i_data_sem));
59 retval = ext4_journal_restart(handle, needed);
60 down_write((&EXT4_I(inode)->i_data_sem));
61 if (retval)
62 goto err_out;
63 } else if (needed) {
64 retval = ext4_journal_extend(handle, needed);
65 if (retval) {
66 /*
67 * IF not able to extend the journal restart the journal
68 */
69 up_write((&EXT4_I(inode)->i_data_sem));
70 retval = ext4_journal_restart(handle, needed);
71 down_write((&EXT4_I(inode)->i_data_sem));
72 if (retval)
73 goto err_out;
74 }
75 }
76 retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
77err_out:
78 up_write((&EXT4_I(inode)->i_data_sem));
79 ext4_ext_drop_refs(path);
80 kfree(path);
81 lb->first_pblock = 0;
82 return retval;
83}
84
85static int update_extent_range(handle_t *handle, struct inode *inode,
86 ext4_fsblk_t pblock, struct migrate_struct *lb)
87{
88 int retval;
89 /*
90 * See if we can add on to the existing range (if it exists)
91 */
92 if (lb->first_pblock &&
93 (lb->last_pblock+1 == pblock) &&
94 (lb->last_block+1 == lb->curr_block)) {
95 lb->last_pblock = pblock;
96 lb->last_block = lb->curr_block;
97 lb->curr_block++;
98 return 0;
99 }
100 /*
101 * Start a new range.
102 */
103 retval = finish_range(handle, inode, lb);
104 lb->first_pblock = lb->last_pblock = pblock;
105 lb->first_block = lb->last_block = lb->curr_block;
106 lb->curr_block++;
107 return retval;
108}
109
110static int update_ind_extent_range(handle_t *handle, struct inode *inode,
111 ext4_fsblk_t pblock,
112 struct migrate_struct *lb)
113{
114 struct buffer_head *bh;
115 __le32 *i_data;
116 int i, retval = 0;
117 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
118
119 bh = sb_bread(inode->i_sb, pblock);
120 if (!bh)
121 return -EIO;
122
123 i_data = (__le32 *)bh->b_data;
124 for (i = 0; i < max_entries; i++) {
125 if (i_data[i]) {
126 retval = update_extent_range(handle, inode,
127 le32_to_cpu(i_data[i]), lb);
128 if (retval)
129 break;
130 } else {
131 lb->curr_block++;
132 }
133 }
134 put_bh(bh);
135 return retval;
136
137}
138
139static int update_dind_extent_range(handle_t *handle, struct inode *inode,
140 ext4_fsblk_t pblock,
141 struct migrate_struct *lb)
142{
143 struct buffer_head *bh;
144 __le32 *i_data;
145 int i, retval = 0;
146 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
147
148 bh = sb_bread(inode->i_sb, pblock);
149 if (!bh)
150 return -EIO;
151
152 i_data = (__le32 *)bh->b_data;
153 for (i = 0; i < max_entries; i++) {
154 if (i_data[i]) {
155 retval = update_ind_extent_range(handle, inode,
156 le32_to_cpu(i_data[i]), lb);
157 if (retval)
158 break;
159 } else {
160 /* Only update the file block number */
161 lb->curr_block += max_entries;
162 }
163 }
164 put_bh(bh);
165 return retval;
166
167}
168
169static int update_tind_extent_range(handle_t *handle, struct inode *inode,
170 ext4_fsblk_t pblock,
171 struct migrate_struct *lb)
172{
173 struct buffer_head *bh;
174 __le32 *i_data;
175 int i, retval = 0;
176 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
177
178 bh = sb_bread(inode->i_sb, pblock);
179 if (!bh)
180 return -EIO;
181
182 i_data = (__le32 *)bh->b_data;
183 for (i = 0; i < max_entries; i++) {
184 if (i_data[i]) {
185 retval = update_dind_extent_range(handle, inode,
186 le32_to_cpu(i_data[i]), lb);
187 if (retval)
188 break;
189 } else {
190 /* Only update the file block number */
191 lb->curr_block += max_entries * max_entries;
192 }
193 }
194 put_bh(bh);
195 return retval;
196
197}
198
199static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
200{
201 int retval = 0, needed;
202
203 if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
204 return 0;
205 /*
206 * We are freeing a blocks. During this we touch
207 * superblock, group descriptor and block bitmap.
208 * So allocate a credit of 3. We may update
209 * quota (user and group).
210 */
211 needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
212
213 if (ext4_journal_extend(handle, needed) != 0)
214 retval = ext4_journal_restart(handle, needed);
215
216 return retval;
217}
218
219static int free_dind_blocks(handle_t *handle,
220 struct inode *inode, __le32 i_data)
221{
222 int i;
223 __le32 *tmp_idata;
224 struct buffer_head *bh;
225 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
226
227 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
228 if (!bh)
229 return -EIO;
230
231 tmp_idata = (__le32 *)bh->b_data;
232 for (i = 0; i < max_entries; i++) {
233 if (tmp_idata[i]) {
234 extend_credit_for_blkdel(handle, inode);
235 ext4_free_blocks(handle, inode, NULL,
236 le32_to_cpu(tmp_idata[i]), 1,
237 EXT4_FREE_BLOCKS_METADATA |
238 EXT4_FREE_BLOCKS_FORGET);
239 }
240 }
241 put_bh(bh);
242 extend_credit_for_blkdel(handle, inode);
243 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
244 EXT4_FREE_BLOCKS_METADATA |
245 EXT4_FREE_BLOCKS_FORGET);
246 return 0;
247}
248
249static int free_tind_blocks(handle_t *handle,
250 struct inode *inode, __le32 i_data)
251{
252 int i, retval = 0;
253 __le32 *tmp_idata;
254 struct buffer_head *bh;
255 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
256
257 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
258 if (!bh)
259 return -EIO;
260
261 tmp_idata = (__le32 *)bh->b_data;
262 for (i = 0; i < max_entries; i++) {
263 if (tmp_idata[i]) {
264 retval = free_dind_blocks(handle,
265 inode, tmp_idata[i]);
266 if (retval) {
267 put_bh(bh);
268 return retval;
269 }
270 }
271 }
272 put_bh(bh);
273 extend_credit_for_blkdel(handle, inode);
274 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
275 EXT4_FREE_BLOCKS_METADATA |
276 EXT4_FREE_BLOCKS_FORGET);
277 return 0;
278}
279
280static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
281{
282 int retval;
283
284 /* ei->i_data[EXT4_IND_BLOCK] */
285 if (i_data[0]) {
286 extend_credit_for_blkdel(handle, inode);
287 ext4_free_blocks(handle, inode, NULL,
288 le32_to_cpu(i_data[0]), 1,
289 EXT4_FREE_BLOCKS_METADATA |
290 EXT4_FREE_BLOCKS_FORGET);
291 }
292
293 /* ei->i_data[EXT4_DIND_BLOCK] */
294 if (i_data[1]) {
295 retval = free_dind_blocks(handle, inode, i_data[1]);
296 if (retval)
297 return retval;
298 }
299
300 /* ei->i_data[EXT4_TIND_BLOCK] */
301 if (i_data[2]) {
302 retval = free_tind_blocks(handle, inode, i_data[2]);
303 if (retval)
304 return retval;
305 }
306 return 0;
307}
308
309static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
310 struct inode *tmp_inode)
311{
312 int retval;
313 __le32 i_data[3];
314 struct ext4_inode_info *ei = EXT4_I(inode);
315 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
316
317 /*
318 * One credit accounted for writing the
319 * i_data field of the original inode
320 */
321 retval = ext4_journal_extend(handle, 1);
322 if (retval) {
323 retval = ext4_journal_restart(handle, 1);
324 if (retval)
325 goto err_out;
326 }
327
328 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
329 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
330 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
331
332 down_write(&EXT4_I(inode)->i_data_sem);
333 /*
334 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
335 * happened after we started the migrate. We need to
336 * fail the migrate
337 */
338 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
339 retval = -EAGAIN;
340 up_write(&EXT4_I(inode)->i_data_sem);
341 goto err_out;
342 } else
343 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
344 /*
345 * We have the extent map build with the tmp inode.
346 * Now copy the i_data across
347 */
348 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
349 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
350
351 /*
352 * Update i_blocks with the new blocks that got
353 * allocated while adding extents for extent index
354 * blocks.
355 *
356 * While converting to extents we need not
357 * update the original inode i_blocks for extent blocks
358 * via quota APIs. The quota update happened via tmp_inode already.
359 */
360 spin_lock(&inode->i_lock);
361 inode->i_blocks += tmp_inode->i_blocks;
362 spin_unlock(&inode->i_lock);
363 up_write(&EXT4_I(inode)->i_data_sem);
364
365 /*
366 * We mark the inode dirty after, because we decrement the
367 * i_blocks when freeing the indirect meta-data blocks
368 */
369 retval = free_ind_block(handle, inode, i_data);
370 ext4_mark_inode_dirty(handle, inode);
371
372err_out:
373 return retval;
374}
375
376static int free_ext_idx(handle_t *handle, struct inode *inode,
377 struct ext4_extent_idx *ix)
378{
379 int i, retval = 0;
380 ext4_fsblk_t block;
381 struct buffer_head *bh;
382 struct ext4_extent_header *eh;
383
384 block = ext4_idx_pblock(ix);
385 bh = sb_bread(inode->i_sb, block);
386 if (!bh)
387 return -EIO;
388
389 eh = (struct ext4_extent_header *)bh->b_data;
390 if (eh->eh_depth != 0) {
391 ix = EXT_FIRST_INDEX(eh);
392 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
393 retval = free_ext_idx(handle, inode, ix);
394 if (retval)
395 break;
396 }
397 }
398 put_bh(bh);
399 extend_credit_for_blkdel(handle, inode);
400 ext4_free_blocks(handle, inode, NULL, block, 1,
401 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
402 return retval;
403}
404
405/*
406 * Free the extent meta data blocks only
407 */
408static int free_ext_block(handle_t *handle, struct inode *inode)
409{
410 int i, retval = 0;
411 struct ext4_inode_info *ei = EXT4_I(inode);
412 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
413 struct ext4_extent_idx *ix;
414 if (eh->eh_depth == 0)
415 /*
416 * No extra blocks allocated for extent meta data
417 */
418 return 0;
419 ix = EXT_FIRST_INDEX(eh);
420 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
421 retval = free_ext_idx(handle, inode, ix);
422 if (retval)
423 return retval;
424 }
425 return retval;
426}
427
428int ext4_ext_migrate(struct inode *inode)
429{
430 handle_t *handle;
431 int retval = 0, i;
432 __le32 *i_data;
433 struct ext4_inode_info *ei;
434 struct inode *tmp_inode = NULL;
435 struct migrate_struct lb;
436 unsigned long max_entries;
437 __u32 goal;
438 uid_t owner[2];
439
440 /*
441 * If the filesystem does not support extents, or the inode
442 * already is extent-based, error out.
443 */
444 if (!ext4_has_feature_extents(inode->i_sb) ||
445 (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
446 return -EINVAL;
447
448 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
449 /*
450 * don't migrate fast symlink
451 */
452 return retval;
453
454 /*
455 * Worst case we can touch the allocation bitmaps, a bgd
456 * block, and a block to link in the orphan list. We do need
457 * need to worry about credits for modifying the quota inode.
458 */
459 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
460 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
461
462 if (IS_ERR(handle)) {
463 retval = PTR_ERR(handle);
464 return retval;
465 }
466 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
467 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
468 owner[0] = i_uid_read(inode);
469 owner[1] = i_gid_read(inode);
470 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
471 S_IFREG, NULL, goal, owner, 0);
472 if (IS_ERR(tmp_inode)) {
473 retval = PTR_ERR(tmp_inode);
474 ext4_journal_stop(handle);
475 return retval;
476 }
477 i_size_write(tmp_inode, i_size_read(inode));
478 /*
479 * Set the i_nlink to zero so it will be deleted later
480 * when we drop inode reference.
481 */
482 clear_nlink(tmp_inode);
483
484 ext4_ext_tree_init(handle, tmp_inode);
485 ext4_orphan_add(handle, tmp_inode);
486 ext4_journal_stop(handle);
487
488 /*
489 * start with one credit accounted for
490 * superblock modification.
491 *
492 * For the tmp_inode we already have committed the
493 * transaction that created the inode. Later as and
494 * when we add extents we extent the journal
495 */
496 /*
497 * Even though we take i_mutex we can still cause block
498 * allocation via mmap write to holes. If we have allocated
499 * new blocks we fail migrate. New block allocation will
500 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
501 * with i_data_sem held to prevent racing with block
502 * allocation.
503 */
504 down_read(&EXT4_I(inode)->i_data_sem);
505 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
506 up_read((&EXT4_I(inode)->i_data_sem));
507
508 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
509 if (IS_ERR(handle)) {
510 /*
511 * It is impossible to update on-disk structures without
512 * a handle, so just rollback in-core changes and live other
513 * work to orphan_list_cleanup()
514 */
515 ext4_orphan_del(NULL, tmp_inode);
516 retval = PTR_ERR(handle);
517 goto out;
518 }
519
520 ei = EXT4_I(inode);
521 i_data = ei->i_data;
522 memset(&lb, 0, sizeof(lb));
523
524 /* 32 bit block address 4 bytes */
525 max_entries = inode->i_sb->s_blocksize >> 2;
526 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
527 if (i_data[i]) {
528 retval = update_extent_range(handle, tmp_inode,
529 le32_to_cpu(i_data[i]), &lb);
530 if (retval)
531 goto err_out;
532 } else
533 lb.curr_block++;
534 }
535 if (i_data[EXT4_IND_BLOCK]) {
536 retval = update_ind_extent_range(handle, tmp_inode,
537 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
538 if (retval)
539 goto err_out;
540 } else
541 lb.curr_block += max_entries;
542 if (i_data[EXT4_DIND_BLOCK]) {
543 retval = update_dind_extent_range(handle, tmp_inode,
544 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
545 if (retval)
546 goto err_out;
547 } else
548 lb.curr_block += max_entries * max_entries;
549 if (i_data[EXT4_TIND_BLOCK]) {
550 retval = update_tind_extent_range(handle, tmp_inode,
551 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
552 if (retval)
553 goto err_out;
554 }
555 /*
556 * Build the last extent
557 */
558 retval = finish_range(handle, tmp_inode, &lb);
559err_out:
560 if (retval)
561 /*
562 * Failure case delete the extent information with the
563 * tmp_inode
564 */
565 free_ext_block(handle, tmp_inode);
566 else {
567 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
568 if (retval)
569 /*
570 * if we fail to swap inode data free the extent
571 * details of the tmp inode
572 */
573 free_ext_block(handle, tmp_inode);
574 }
575
576 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
577 if (ext4_journal_extend(handle, 1) != 0)
578 ext4_journal_restart(handle, 1);
579
580 /*
581 * Mark the tmp_inode as of size zero
582 */
583 i_size_write(tmp_inode, 0);
584
585 /*
586 * set the i_blocks count to zero
587 * so that the ext4_evict_inode() does the
588 * right job
589 *
590 * We don't need to take the i_lock because
591 * the inode is not visible to user space.
592 */
593 tmp_inode->i_blocks = 0;
594
595 /* Reset the extent details */
596 ext4_ext_tree_init(handle, tmp_inode);
597 ext4_journal_stop(handle);
598out:
599 unlock_new_inode(tmp_inode);
600 iput(tmp_inode);
601
602 return retval;
603}
604
605/*
606 * Migrate a simple extent-based inode to use the i_blocks[] array
607 */
608int ext4_ind_migrate(struct inode *inode)
609{
610 struct ext4_extent_header *eh;
611 struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
612 struct ext4_inode_info *ei = EXT4_I(inode);
613 struct ext4_extent *ex;
614 unsigned int i, len;
615 ext4_lblk_t start, end;
616 ext4_fsblk_t blk;
617 handle_t *handle;
618 int ret;
619
620 if (!ext4_has_feature_extents(inode->i_sb) ||
621 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
622 return -EINVAL;
623
624 if (ext4_has_feature_bigalloc(inode->i_sb))
625 return -EOPNOTSUPP;
626
627 /*
628 * In order to get correct extent info, force all delayed allocation
629 * blocks to be allocated, otherwise delayed allocation blocks may not
630 * be reflected and bypass the checks on extent header.
631 */
632 if (test_opt(inode->i_sb, DELALLOC))
633 ext4_alloc_da_blocks(inode);
634
635 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
636 if (IS_ERR(handle))
637 return PTR_ERR(handle);
638
639 down_write(&EXT4_I(inode)->i_data_sem);
640 ret = ext4_ext_check_inode(inode);
641 if (ret)
642 goto errout;
643
644 eh = ext_inode_hdr(inode);
645 ex = EXT_FIRST_EXTENT(eh);
646 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
647 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
648 ret = -EOPNOTSUPP;
649 goto errout;
650 }
651 if (eh->eh_entries == 0)
652 blk = len = start = end = 0;
653 else {
654 len = le16_to_cpu(ex->ee_len);
655 blk = ext4_ext_pblock(ex);
656 start = le32_to_cpu(ex->ee_block);
657 end = start + len - 1;
658 if (end >= EXT4_NDIR_BLOCKS) {
659 ret = -EOPNOTSUPP;
660 goto errout;
661 }
662 }
663
664 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
665 memset(ei->i_data, 0, sizeof(ei->i_data));
666 for (i = start; i <= end; i++)
667 ei->i_data[i] = cpu_to_le32(blk++);
668 ext4_mark_inode_dirty(handle, inode);
669errout:
670 ext4_journal_stop(handle);
671 up_write(&EXT4_I(inode)->i_data_sem);
672 return ret;
673}