Loading...
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#include "ext4_extents.h"
18
19/*
20 * The contiguous blocks details which can be
21 * represented by a single extent
22 */
23struct migrate_struct {
24 ext4_lblk_t first_block, last_block, curr_block;
25 ext4_fsblk_t first_pblock, last_pblock;
26};
27
28static int finish_range(handle_t *handle, struct inode *inode,
29 struct migrate_struct *lb)
30
31{
32 int retval = 0, needed;
33 struct ext4_extent newext;
34 struct ext4_ext_path *path;
35 if (lb->first_pblock == 0)
36 return 0;
37
38 /* Add the extent to temp inode*/
39 newext.ee_block = cpu_to_le32(lb->first_block);
40 newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
41 ext4_ext_store_pblock(&newext, lb->first_pblock);
42 /* Locking only for convinience since we are operating on temp inode */
43 down_write(&EXT4_I(inode)->i_data_sem);
44 path = ext4_find_extent(inode, lb->first_block, NULL, 0);
45 if (IS_ERR(path)) {
46 retval = PTR_ERR(path);
47 path = NULL;
48 goto err_out;
49 }
50
51 /*
52 * Calculate the credit needed to inserting this extent
53 * Since we are doing this in loop we may accumalate extra
54 * credit. But below we try to not accumalate too much
55 * of them by restarting the journal.
56 */
57 needed = ext4_ext_calc_credits_for_single_extent(inode,
58 lb->last_block - lb->first_block + 1, path);
59
60 /*
61 * Make sure the credit we accumalated is not really high
62 */
63 if (needed && ext4_handle_has_enough_credits(handle,
64 EXT4_RESERVE_TRANS_BLOCKS)) {
65 up_write((&EXT4_I(inode)->i_data_sem));
66 retval = ext4_journal_restart(handle, needed);
67 down_write((&EXT4_I(inode)->i_data_sem));
68 if (retval)
69 goto err_out;
70 } else if (needed) {
71 retval = ext4_journal_extend(handle, needed);
72 if (retval) {
73 /*
74 * IF not able to extend the journal restart the journal
75 */
76 up_write((&EXT4_I(inode)->i_data_sem));
77 retval = ext4_journal_restart(handle, needed);
78 down_write((&EXT4_I(inode)->i_data_sem));
79 if (retval)
80 goto err_out;
81 }
82 }
83 retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
84err_out:
85 up_write((&EXT4_I(inode)->i_data_sem));
86 ext4_ext_drop_refs(path);
87 kfree(path);
88 lb->first_pblock = 0;
89 return retval;
90}
91
92static int update_extent_range(handle_t *handle, struct inode *inode,
93 ext4_fsblk_t pblock, struct migrate_struct *lb)
94{
95 int retval;
96 /*
97 * See if we can add on to the existing range (if it exists)
98 */
99 if (lb->first_pblock &&
100 (lb->last_pblock+1 == pblock) &&
101 (lb->last_block+1 == lb->curr_block)) {
102 lb->last_pblock = pblock;
103 lb->last_block = lb->curr_block;
104 lb->curr_block++;
105 return 0;
106 }
107 /*
108 * Start a new range.
109 */
110 retval = finish_range(handle, inode, lb);
111 lb->first_pblock = lb->last_pblock = pblock;
112 lb->first_block = lb->last_block = lb->curr_block;
113 lb->curr_block++;
114 return retval;
115}
116
117static int update_ind_extent_range(handle_t *handle, struct inode *inode,
118 ext4_fsblk_t pblock,
119 struct migrate_struct *lb)
120{
121 struct buffer_head *bh;
122 __le32 *i_data;
123 int i, retval = 0;
124 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
125
126 bh = sb_bread(inode->i_sb, pblock);
127 if (!bh)
128 return -EIO;
129
130 i_data = (__le32 *)bh->b_data;
131 for (i = 0; i < max_entries; i++) {
132 if (i_data[i]) {
133 retval = update_extent_range(handle, inode,
134 le32_to_cpu(i_data[i]), lb);
135 if (retval)
136 break;
137 } else {
138 lb->curr_block++;
139 }
140 }
141 put_bh(bh);
142 return retval;
143
144}
145
146static int update_dind_extent_range(handle_t *handle, struct inode *inode,
147 ext4_fsblk_t pblock,
148 struct migrate_struct *lb)
149{
150 struct buffer_head *bh;
151 __le32 *i_data;
152 int i, retval = 0;
153 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
154
155 bh = sb_bread(inode->i_sb, pblock);
156 if (!bh)
157 return -EIO;
158
159 i_data = (__le32 *)bh->b_data;
160 for (i = 0; i < max_entries; i++) {
161 if (i_data[i]) {
162 retval = update_ind_extent_range(handle, inode,
163 le32_to_cpu(i_data[i]), lb);
164 if (retval)
165 break;
166 } else {
167 /* Only update the file block number */
168 lb->curr_block += max_entries;
169 }
170 }
171 put_bh(bh);
172 return retval;
173
174}
175
176static int update_tind_extent_range(handle_t *handle, struct inode *inode,
177 ext4_fsblk_t pblock,
178 struct migrate_struct *lb)
179{
180 struct buffer_head *bh;
181 __le32 *i_data;
182 int i, retval = 0;
183 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
184
185 bh = sb_bread(inode->i_sb, pblock);
186 if (!bh)
187 return -EIO;
188
189 i_data = (__le32 *)bh->b_data;
190 for (i = 0; i < max_entries; i++) {
191 if (i_data[i]) {
192 retval = update_dind_extent_range(handle, inode,
193 le32_to_cpu(i_data[i]), lb);
194 if (retval)
195 break;
196 } else {
197 /* Only update the file block number */
198 lb->curr_block += max_entries * max_entries;
199 }
200 }
201 put_bh(bh);
202 return retval;
203
204}
205
206static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
207{
208 int retval = 0, needed;
209
210 if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
211 return 0;
212 /*
213 * We are freeing a blocks. During this we touch
214 * superblock, group descriptor and block bitmap.
215 * So allocate a credit of 3. We may update
216 * quota (user and group).
217 */
218 needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
219
220 if (ext4_journal_extend(handle, needed) != 0)
221 retval = ext4_journal_restart(handle, needed);
222
223 return retval;
224}
225
226static int free_dind_blocks(handle_t *handle,
227 struct inode *inode, __le32 i_data)
228{
229 int i;
230 __le32 *tmp_idata;
231 struct buffer_head *bh;
232 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
233
234 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
235 if (!bh)
236 return -EIO;
237
238 tmp_idata = (__le32 *)bh->b_data;
239 for (i = 0; i < max_entries; i++) {
240 if (tmp_idata[i]) {
241 extend_credit_for_blkdel(handle, inode);
242 ext4_free_blocks(handle, inode, NULL,
243 le32_to_cpu(tmp_idata[i]), 1,
244 EXT4_FREE_BLOCKS_METADATA |
245 EXT4_FREE_BLOCKS_FORGET);
246 }
247 }
248 put_bh(bh);
249 extend_credit_for_blkdel(handle, inode);
250 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
251 EXT4_FREE_BLOCKS_METADATA |
252 EXT4_FREE_BLOCKS_FORGET);
253 return 0;
254}
255
256static int free_tind_blocks(handle_t *handle,
257 struct inode *inode, __le32 i_data)
258{
259 int i, retval = 0;
260 __le32 *tmp_idata;
261 struct buffer_head *bh;
262 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
263
264 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
265 if (!bh)
266 return -EIO;
267
268 tmp_idata = (__le32 *)bh->b_data;
269 for (i = 0; i < max_entries; i++) {
270 if (tmp_idata[i]) {
271 retval = free_dind_blocks(handle,
272 inode, tmp_idata[i]);
273 if (retval) {
274 put_bh(bh);
275 return retval;
276 }
277 }
278 }
279 put_bh(bh);
280 extend_credit_for_blkdel(handle, inode);
281 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
282 EXT4_FREE_BLOCKS_METADATA |
283 EXT4_FREE_BLOCKS_FORGET);
284 return 0;
285}
286
287static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
288{
289 int retval;
290
291 /* ei->i_data[EXT4_IND_BLOCK] */
292 if (i_data[0]) {
293 extend_credit_for_blkdel(handle, inode);
294 ext4_free_blocks(handle, inode, NULL,
295 le32_to_cpu(i_data[0]), 1,
296 EXT4_FREE_BLOCKS_METADATA |
297 EXT4_FREE_BLOCKS_FORGET);
298 }
299
300 /* ei->i_data[EXT4_DIND_BLOCK] */
301 if (i_data[1]) {
302 retval = free_dind_blocks(handle, inode, i_data[1]);
303 if (retval)
304 return retval;
305 }
306
307 /* ei->i_data[EXT4_TIND_BLOCK] */
308 if (i_data[2]) {
309 retval = free_tind_blocks(handle, inode, i_data[2]);
310 if (retval)
311 return retval;
312 }
313 return 0;
314}
315
316static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
317 struct inode *tmp_inode)
318{
319 int retval;
320 __le32 i_data[3];
321 struct ext4_inode_info *ei = EXT4_I(inode);
322 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
323
324 /*
325 * One credit accounted for writing the
326 * i_data field of the original inode
327 */
328 retval = ext4_journal_extend(handle, 1);
329 if (retval) {
330 retval = ext4_journal_restart(handle, 1);
331 if (retval)
332 goto err_out;
333 }
334
335 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
336 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
337 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
338
339 down_write(&EXT4_I(inode)->i_data_sem);
340 /*
341 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
342 * happened after we started the migrate. We need to
343 * fail the migrate
344 */
345 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
346 retval = -EAGAIN;
347 up_write(&EXT4_I(inode)->i_data_sem);
348 goto err_out;
349 } else
350 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
351 /*
352 * We have the extent map build with the tmp inode.
353 * Now copy the i_data across
354 */
355 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
356 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
357
358 /*
359 * Update i_blocks with the new blocks that got
360 * allocated while adding extents for extent index
361 * blocks.
362 *
363 * While converting to extents we need not
364 * update the original inode i_blocks for extent blocks
365 * via quota APIs. The quota update happened via tmp_inode already.
366 */
367 spin_lock(&inode->i_lock);
368 inode->i_blocks += tmp_inode->i_blocks;
369 spin_unlock(&inode->i_lock);
370 up_write(&EXT4_I(inode)->i_data_sem);
371
372 /*
373 * We mark the inode dirty after, because we decrement the
374 * i_blocks when freeing the indirect meta-data blocks
375 */
376 retval = free_ind_block(handle, inode, i_data);
377 ext4_mark_inode_dirty(handle, inode);
378
379err_out:
380 return retval;
381}
382
383static int free_ext_idx(handle_t *handle, struct inode *inode,
384 struct ext4_extent_idx *ix)
385{
386 int i, retval = 0;
387 ext4_fsblk_t block;
388 struct buffer_head *bh;
389 struct ext4_extent_header *eh;
390
391 block = ext4_idx_pblock(ix);
392 bh = sb_bread(inode->i_sb, block);
393 if (!bh)
394 return -EIO;
395
396 eh = (struct ext4_extent_header *)bh->b_data;
397 if (eh->eh_depth != 0) {
398 ix = EXT_FIRST_INDEX(eh);
399 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
400 retval = free_ext_idx(handle, inode, ix);
401 if (retval)
402 break;
403 }
404 }
405 put_bh(bh);
406 extend_credit_for_blkdel(handle, inode);
407 ext4_free_blocks(handle, inode, NULL, block, 1,
408 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
409 return retval;
410}
411
412/*
413 * Free the extent meta data blocks only
414 */
415static int free_ext_block(handle_t *handle, struct inode *inode)
416{
417 int i, retval = 0;
418 struct ext4_inode_info *ei = EXT4_I(inode);
419 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
420 struct ext4_extent_idx *ix;
421 if (eh->eh_depth == 0)
422 /*
423 * No extra blocks allocated for extent meta data
424 */
425 return 0;
426 ix = EXT_FIRST_INDEX(eh);
427 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
428 retval = free_ext_idx(handle, inode, ix);
429 if (retval)
430 return retval;
431 }
432 return retval;
433}
434
435int ext4_ext_migrate(struct inode *inode)
436{
437 handle_t *handle;
438 int retval = 0, i;
439 __le32 *i_data;
440 struct ext4_inode_info *ei;
441 struct inode *tmp_inode = NULL;
442 struct migrate_struct lb;
443 unsigned long max_entries;
444 __u32 goal;
445 uid_t owner[2];
446
447 /*
448 * If the filesystem does not support extents, or the inode
449 * already is extent-based, error out.
450 */
451 if (!ext4_has_feature_extents(inode->i_sb) ||
452 (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
453 return -EINVAL;
454
455 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
456 /*
457 * don't migrate fast symlink
458 */
459 return retval;
460
461 /*
462 * Worst case we can touch the allocation bitmaps, a bgd
463 * block, and a block to link in the orphan list. We do need
464 * need to worry about credits for modifying the quota inode.
465 */
466 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
467 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
468
469 if (IS_ERR(handle)) {
470 retval = PTR_ERR(handle);
471 return retval;
472 }
473 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
474 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
475 owner[0] = i_uid_read(inode);
476 owner[1] = i_gid_read(inode);
477 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
478 S_IFREG, NULL, goal, owner);
479 if (IS_ERR(tmp_inode)) {
480 retval = PTR_ERR(tmp_inode);
481 ext4_journal_stop(handle);
482 return retval;
483 }
484 i_size_write(tmp_inode, i_size_read(inode));
485 /*
486 * Set the i_nlink to zero so it will be deleted later
487 * when we drop inode reference.
488 */
489 clear_nlink(tmp_inode);
490
491 ext4_ext_tree_init(handle, tmp_inode);
492 ext4_orphan_add(handle, tmp_inode);
493 ext4_journal_stop(handle);
494
495 /*
496 * start with one credit accounted for
497 * superblock modification.
498 *
499 * For the tmp_inode we already have committed the
500 * transaction that created the inode. Later as and
501 * when we add extents we extent the journal
502 */
503 /*
504 * Even though we take i_mutex we can still cause block
505 * allocation via mmap write to holes. If we have allocated
506 * new blocks we fail migrate. New block allocation will
507 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
508 * with i_data_sem held to prevent racing with block
509 * allocation.
510 */
511 down_read(&EXT4_I(inode)->i_data_sem);
512 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
513 up_read((&EXT4_I(inode)->i_data_sem));
514
515 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
516 if (IS_ERR(handle)) {
517 /*
518 * It is impossible to update on-disk structures without
519 * a handle, so just rollback in-core changes and live other
520 * work to orphan_list_cleanup()
521 */
522 ext4_orphan_del(NULL, tmp_inode);
523 retval = PTR_ERR(handle);
524 goto out;
525 }
526
527 ei = EXT4_I(inode);
528 i_data = ei->i_data;
529 memset(&lb, 0, sizeof(lb));
530
531 /* 32 bit block address 4 bytes */
532 max_entries = inode->i_sb->s_blocksize >> 2;
533 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
534 if (i_data[i]) {
535 retval = update_extent_range(handle, tmp_inode,
536 le32_to_cpu(i_data[i]), &lb);
537 if (retval)
538 goto err_out;
539 } else
540 lb.curr_block++;
541 }
542 if (i_data[EXT4_IND_BLOCK]) {
543 retval = update_ind_extent_range(handle, tmp_inode,
544 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
545 if (retval)
546 goto err_out;
547 } else
548 lb.curr_block += max_entries;
549 if (i_data[EXT4_DIND_BLOCK]) {
550 retval = update_dind_extent_range(handle, tmp_inode,
551 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
552 if (retval)
553 goto err_out;
554 } else
555 lb.curr_block += max_entries * max_entries;
556 if (i_data[EXT4_TIND_BLOCK]) {
557 retval = update_tind_extent_range(handle, tmp_inode,
558 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
559 if (retval)
560 goto err_out;
561 }
562 /*
563 * Build the last extent
564 */
565 retval = finish_range(handle, tmp_inode, &lb);
566err_out:
567 if (retval)
568 /*
569 * Failure case delete the extent information with the
570 * tmp_inode
571 */
572 free_ext_block(handle, tmp_inode);
573 else {
574 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
575 if (retval)
576 /*
577 * if we fail to swap inode data free the extent
578 * details of the tmp inode
579 */
580 free_ext_block(handle, tmp_inode);
581 }
582
583 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
584 if (ext4_journal_extend(handle, 1) != 0)
585 ext4_journal_restart(handle, 1);
586
587 /*
588 * Mark the tmp_inode as of size zero
589 */
590 i_size_write(tmp_inode, 0);
591
592 /*
593 * set the i_blocks count to zero
594 * so that the ext4_evict_inode() does the
595 * right job
596 *
597 * We don't need to take the i_lock because
598 * the inode is not visible to user space.
599 */
600 tmp_inode->i_blocks = 0;
601
602 /* Reset the extent details */
603 ext4_ext_tree_init(handle, tmp_inode);
604 ext4_journal_stop(handle);
605out:
606 unlock_new_inode(tmp_inode);
607 iput(tmp_inode);
608
609 return retval;
610}
611
612/*
613 * Migrate a simple extent-based inode to use the i_blocks[] array
614 */
615int ext4_ind_migrate(struct inode *inode)
616{
617 struct ext4_extent_header *eh;
618 struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
619 struct ext4_inode_info *ei = EXT4_I(inode);
620 struct ext4_extent *ex;
621 unsigned int i, len;
622 ext4_lblk_t start, end;
623 ext4_fsblk_t blk;
624 handle_t *handle;
625 int ret;
626
627 if (!ext4_has_feature_extents(inode->i_sb) ||
628 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
629 return -EINVAL;
630
631 if (ext4_has_feature_bigalloc(inode->i_sb))
632 return -EOPNOTSUPP;
633
634 /*
635 * In order to get correct extent info, force all delayed allocation
636 * blocks to be allocated, otherwise delayed allocation blocks may not
637 * be reflected and bypass the checks on extent header.
638 */
639 if (test_opt(inode->i_sb, DELALLOC))
640 ext4_alloc_da_blocks(inode);
641
642 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
643 if (IS_ERR(handle))
644 return PTR_ERR(handle);
645
646 down_write(&EXT4_I(inode)->i_data_sem);
647 ret = ext4_ext_check_inode(inode);
648 if (ret)
649 goto errout;
650
651 eh = ext_inode_hdr(inode);
652 ex = EXT_FIRST_EXTENT(eh);
653 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
654 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
655 ret = -EOPNOTSUPP;
656 goto errout;
657 }
658 if (eh->eh_entries == 0)
659 blk = len = start = end = 0;
660 else {
661 len = le16_to_cpu(ex->ee_len);
662 blk = ext4_ext_pblock(ex);
663 start = le32_to_cpu(ex->ee_block);
664 end = start + len - 1;
665 if (end >= EXT4_NDIR_BLOCKS) {
666 ret = -EOPNOTSUPP;
667 goto errout;
668 }
669 }
670
671 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
672 memset(ei->i_data, 0, sizeof(ei->i_data));
673 for (i = start; i <= end; i++)
674 ei->i_data[i] = cpu_to_le32(blk++);
675 ext4_mark_inode_dirty(handle, inode);
676errout:
677 ext4_journal_stop(handle);
678 up_write(&EXT4_I(inode)->i_data_sem);
679 return ret;
680}
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 convenience 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 accumulate extra
47 * credit. But below we try to not accumulate 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 retval = ext4_datasem_ensure_credits(handle, inode, needed, needed, 0);
54 if (retval < 0)
55 goto err_out;
56 retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
57err_out:
58 up_write((&EXT4_I(inode)->i_data_sem));
59 ext4_free_ext_path(path);
60 lb->first_pblock = 0;
61 return retval;
62}
63
64static int update_extent_range(handle_t *handle, struct inode *inode,
65 ext4_fsblk_t pblock, struct migrate_struct *lb)
66{
67 int retval;
68 /*
69 * See if we can add on to the existing range (if it exists)
70 */
71 if (lb->first_pblock &&
72 (lb->last_pblock+1 == pblock) &&
73 (lb->last_block+1 == lb->curr_block)) {
74 lb->last_pblock = pblock;
75 lb->last_block = lb->curr_block;
76 lb->curr_block++;
77 return 0;
78 }
79 /*
80 * Start a new range.
81 */
82 retval = finish_range(handle, inode, lb);
83 lb->first_pblock = lb->last_pblock = pblock;
84 lb->first_block = lb->last_block = lb->curr_block;
85 lb->curr_block++;
86 return retval;
87}
88
89static int update_ind_extent_range(handle_t *handle, struct inode *inode,
90 ext4_fsblk_t pblock,
91 struct migrate_struct *lb)
92{
93 struct buffer_head *bh;
94 __le32 *i_data;
95 int i, retval = 0;
96 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
97
98 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
99 if (IS_ERR(bh))
100 return PTR_ERR(bh);
101
102 i_data = (__le32 *)bh->b_data;
103 for (i = 0; i < max_entries; i++) {
104 if (i_data[i]) {
105 retval = update_extent_range(handle, inode,
106 le32_to_cpu(i_data[i]), lb);
107 if (retval)
108 break;
109 } else {
110 lb->curr_block++;
111 }
112 }
113 put_bh(bh);
114 return retval;
115
116}
117
118static int update_dind_extent_range(handle_t *handle, struct inode *inode,
119 ext4_fsblk_t pblock,
120 struct migrate_struct *lb)
121{
122 struct buffer_head *bh;
123 __le32 *i_data;
124 int i, retval = 0;
125 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
126
127 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
128 if (IS_ERR(bh))
129 return PTR_ERR(bh);
130
131 i_data = (__le32 *)bh->b_data;
132 for (i = 0; i < max_entries; i++) {
133 if (i_data[i]) {
134 retval = update_ind_extent_range(handle, inode,
135 le32_to_cpu(i_data[i]), lb);
136 if (retval)
137 break;
138 } else {
139 /* Only update the file block number */
140 lb->curr_block += max_entries;
141 }
142 }
143 put_bh(bh);
144 return retval;
145
146}
147
148static int update_tind_extent_range(handle_t *handle, struct inode *inode,
149 ext4_fsblk_t pblock,
150 struct migrate_struct *lb)
151{
152 struct buffer_head *bh;
153 __le32 *i_data;
154 int i, retval = 0;
155 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
156
157 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
158 if (IS_ERR(bh))
159 return PTR_ERR(bh);
160
161 i_data = (__le32 *)bh->b_data;
162 for (i = 0; i < max_entries; i++) {
163 if (i_data[i]) {
164 retval = update_dind_extent_range(handle, inode,
165 le32_to_cpu(i_data[i]), lb);
166 if (retval)
167 break;
168 } else {
169 /* Only update the file block number */
170 lb->curr_block += max_entries * max_entries;
171 }
172 }
173 put_bh(bh);
174 return retval;
175
176}
177
178static int free_dind_blocks(handle_t *handle,
179 struct inode *inode, __le32 i_data)
180{
181 int i;
182 __le32 *tmp_idata;
183 struct buffer_head *bh;
184 struct super_block *sb = inode->i_sb;
185 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
186 int err;
187
188 bh = ext4_sb_bread(sb, le32_to_cpu(i_data), 0);
189 if (IS_ERR(bh))
190 return PTR_ERR(bh);
191
192 tmp_idata = (__le32 *)bh->b_data;
193 for (i = 0; i < max_entries; i++) {
194 if (tmp_idata[i]) {
195 err = ext4_journal_ensure_credits(handle,
196 EXT4_RESERVE_TRANS_BLOCKS,
197 ext4_free_metadata_revoke_credits(sb, 1));
198 if (err < 0) {
199 put_bh(bh);
200 return err;
201 }
202 ext4_free_blocks(handle, inode, NULL,
203 le32_to_cpu(tmp_idata[i]), 1,
204 EXT4_FREE_BLOCKS_METADATA |
205 EXT4_FREE_BLOCKS_FORGET);
206 }
207 }
208 put_bh(bh);
209 err = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
210 ext4_free_metadata_revoke_credits(sb, 1));
211 if (err < 0)
212 return err;
213 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
214 EXT4_FREE_BLOCKS_METADATA |
215 EXT4_FREE_BLOCKS_FORGET);
216 return 0;
217}
218
219static int free_tind_blocks(handle_t *handle,
220 struct inode *inode, __le32 i_data)
221{
222 int i, retval = 0;
223 __le32 *tmp_idata;
224 struct buffer_head *bh;
225 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
226
227 bh = ext4_sb_bread(inode->i_sb, le32_to_cpu(i_data), 0);
228 if (IS_ERR(bh))
229 return PTR_ERR(bh);
230
231 tmp_idata = (__le32 *)bh->b_data;
232 for (i = 0; i < max_entries; i++) {
233 if (tmp_idata[i]) {
234 retval = free_dind_blocks(handle,
235 inode, tmp_idata[i]);
236 if (retval) {
237 put_bh(bh);
238 return retval;
239 }
240 }
241 }
242 put_bh(bh);
243 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
244 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
245 if (retval < 0)
246 return retval;
247 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
248 EXT4_FREE_BLOCKS_METADATA |
249 EXT4_FREE_BLOCKS_FORGET);
250 return 0;
251}
252
253static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
254{
255 int retval;
256
257 /* ei->i_data[EXT4_IND_BLOCK] */
258 if (i_data[0]) {
259 retval = ext4_journal_ensure_credits(handle,
260 EXT4_RESERVE_TRANS_BLOCKS,
261 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
262 if (retval < 0)
263 return retval;
264 ext4_free_blocks(handle, inode, NULL,
265 le32_to_cpu(i_data[0]), 1,
266 EXT4_FREE_BLOCKS_METADATA |
267 EXT4_FREE_BLOCKS_FORGET);
268 }
269
270 /* ei->i_data[EXT4_DIND_BLOCK] */
271 if (i_data[1]) {
272 retval = free_dind_blocks(handle, inode, i_data[1]);
273 if (retval)
274 return retval;
275 }
276
277 /* ei->i_data[EXT4_TIND_BLOCK] */
278 if (i_data[2]) {
279 retval = free_tind_blocks(handle, inode, i_data[2]);
280 if (retval)
281 return retval;
282 }
283 return 0;
284}
285
286static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
287 struct inode *tmp_inode)
288{
289 int retval, retval2 = 0;
290 __le32 i_data[3];
291 struct ext4_inode_info *ei = EXT4_I(inode);
292 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
293
294 /*
295 * One credit accounted for writing the
296 * i_data field of the original inode
297 */
298 retval = ext4_journal_ensure_credits(handle, 1, 0);
299 if (retval < 0)
300 goto err_out;
301
302 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
303 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
304 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
305
306 down_write(&EXT4_I(inode)->i_data_sem);
307 /*
308 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
309 * happened after we started the migrate. We need to
310 * fail the migrate
311 */
312 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
313 retval = -EAGAIN;
314 up_write(&EXT4_I(inode)->i_data_sem);
315 goto err_out;
316 } else
317 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
318 /*
319 * We have the extent map build with the tmp inode.
320 * Now copy the i_data across
321 */
322 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
323 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
324
325 /*
326 * Update i_blocks with the new blocks that got
327 * allocated while adding extents for extent index
328 * blocks.
329 *
330 * While converting to extents we need not
331 * update the original inode i_blocks for extent blocks
332 * via quota APIs. The quota update happened via tmp_inode already.
333 */
334 spin_lock(&inode->i_lock);
335 inode->i_blocks += tmp_inode->i_blocks;
336 spin_unlock(&inode->i_lock);
337 up_write(&EXT4_I(inode)->i_data_sem);
338
339 /*
340 * We mark the inode dirty after, because we decrement the
341 * i_blocks when freeing the indirect meta-data blocks
342 */
343 retval = free_ind_block(handle, inode, i_data);
344 retval2 = ext4_mark_inode_dirty(handle, inode);
345 if (unlikely(retval2 && !retval))
346 retval = retval2;
347
348err_out:
349 return retval;
350}
351
352static int free_ext_idx(handle_t *handle, struct inode *inode,
353 struct ext4_extent_idx *ix)
354{
355 int i, retval = 0;
356 ext4_fsblk_t block;
357 struct buffer_head *bh;
358 struct ext4_extent_header *eh;
359
360 block = ext4_idx_pblock(ix);
361 bh = ext4_sb_bread(inode->i_sb, block, 0);
362 if (IS_ERR(bh))
363 return PTR_ERR(bh);
364
365 eh = (struct ext4_extent_header *)bh->b_data;
366 if (eh->eh_depth != 0) {
367 ix = EXT_FIRST_INDEX(eh);
368 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
369 retval = free_ext_idx(handle, inode, ix);
370 if (retval) {
371 put_bh(bh);
372 return retval;
373 }
374 }
375 }
376 put_bh(bh);
377 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
378 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
379 if (retval < 0)
380 return retval;
381 ext4_free_blocks(handle, inode, NULL, block, 1,
382 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
383 return 0;
384}
385
386/*
387 * Free the extent meta data blocks only
388 */
389static int free_ext_block(handle_t *handle, struct inode *inode)
390{
391 int i, retval = 0;
392 struct ext4_inode_info *ei = EXT4_I(inode);
393 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
394 struct ext4_extent_idx *ix;
395 if (eh->eh_depth == 0)
396 /*
397 * No extra blocks allocated for extent meta data
398 */
399 return 0;
400 ix = EXT_FIRST_INDEX(eh);
401 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
402 retval = free_ext_idx(handle, inode, ix);
403 if (retval)
404 return retval;
405 }
406 return retval;
407}
408
409int ext4_ext_migrate(struct inode *inode)
410{
411 handle_t *handle;
412 int retval = 0, i;
413 __le32 *i_data;
414 struct ext4_inode_info *ei;
415 struct inode *tmp_inode = NULL;
416 struct migrate_struct lb;
417 unsigned long max_entries;
418 __u32 goal, tmp_csum_seed;
419 uid_t owner[2];
420 int alloc_ctx;
421
422 /*
423 * If the filesystem does not support extents, or the inode
424 * already is extent-based, error out.
425 */
426 if (!ext4_has_feature_extents(inode->i_sb) ||
427 ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) ||
428 ext4_has_inline_data(inode))
429 return -EINVAL;
430
431 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
432 /*
433 * don't migrate fast symlink
434 */
435 return retval;
436
437 alloc_ctx = ext4_writepages_down_write(inode->i_sb);
438
439 /*
440 * Worst case we can touch the allocation bitmaps and a block
441 * group descriptor block. We do need to worry about
442 * credits for modifying the quota inode.
443 */
444 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
445 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
446
447 if (IS_ERR(handle)) {
448 retval = PTR_ERR(handle);
449 goto out_unlock;
450 }
451 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
452 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
453 owner[0] = i_uid_read(inode);
454 owner[1] = i_gid_read(inode);
455 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
456 S_IFREG, NULL, goal, owner, 0);
457 if (IS_ERR(tmp_inode)) {
458 retval = PTR_ERR(tmp_inode);
459 ext4_journal_stop(handle);
460 goto out_unlock;
461 }
462 /*
463 * Use the correct seed for checksum (i.e. the seed from 'inode'). This
464 * is so that the metadata blocks will have the correct checksum after
465 * the migration.
466 */
467 ei = EXT4_I(inode);
468 tmp_csum_seed = EXT4_I(tmp_inode)->i_csum_seed;
469 EXT4_I(tmp_inode)->i_csum_seed = ei->i_csum_seed;
470 i_size_write(tmp_inode, i_size_read(inode));
471 /*
472 * Set the i_nlink to zero so it will be deleted later
473 * when we drop inode reference.
474 */
475 clear_nlink(tmp_inode);
476
477 ext4_ext_tree_init(handle, tmp_inode);
478 ext4_journal_stop(handle);
479
480 /*
481 * start with one credit accounted for
482 * superblock modification.
483 *
484 * For the tmp_inode we already have committed the
485 * transaction that created the inode. Later as and
486 * when we add extents we extent the journal
487 */
488 /*
489 * Even though we take i_rwsem we can still cause block
490 * allocation via mmap write to holes. If we have allocated
491 * new blocks we fail migrate. New block allocation will
492 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
493 * with i_data_sem held to prevent racing with block
494 * allocation.
495 */
496 down_read(&EXT4_I(inode)->i_data_sem);
497 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
498 up_read((&EXT4_I(inode)->i_data_sem));
499
500 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
501 if (IS_ERR(handle)) {
502 retval = PTR_ERR(handle);
503 goto out_tmp_inode;
504 }
505
506 i_data = ei->i_data;
507 memset(&lb, 0, sizeof(lb));
508
509 /* 32 bit block address 4 bytes */
510 max_entries = inode->i_sb->s_blocksize >> 2;
511 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
512 if (i_data[i]) {
513 retval = update_extent_range(handle, tmp_inode,
514 le32_to_cpu(i_data[i]), &lb);
515 if (retval)
516 goto err_out;
517 } else
518 lb.curr_block++;
519 }
520 if (i_data[EXT4_IND_BLOCK]) {
521 retval = update_ind_extent_range(handle, tmp_inode,
522 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
523 if (retval)
524 goto err_out;
525 } else
526 lb.curr_block += max_entries;
527 if (i_data[EXT4_DIND_BLOCK]) {
528 retval = update_dind_extent_range(handle, tmp_inode,
529 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
530 if (retval)
531 goto err_out;
532 } else
533 lb.curr_block += max_entries * max_entries;
534 if (i_data[EXT4_TIND_BLOCK]) {
535 retval = update_tind_extent_range(handle, tmp_inode,
536 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
537 if (retval)
538 goto err_out;
539 }
540 /*
541 * Build the last extent
542 */
543 retval = finish_range(handle, tmp_inode, &lb);
544err_out:
545 if (retval)
546 /*
547 * Failure case delete the extent information with the
548 * tmp_inode
549 */
550 free_ext_block(handle, tmp_inode);
551 else {
552 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
553 if (retval)
554 /*
555 * if we fail to swap inode data free the extent
556 * details of the tmp inode
557 */
558 free_ext_block(handle, tmp_inode);
559 }
560
561 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
562 retval = ext4_journal_ensure_credits(handle, 1, 0);
563 if (retval < 0)
564 goto out_stop;
565 /*
566 * Mark the tmp_inode as of size zero
567 */
568 i_size_write(tmp_inode, 0);
569
570 /*
571 * set the i_blocks count to zero
572 * so that the ext4_evict_inode() does the
573 * right job
574 *
575 * We don't need to take the i_lock because
576 * the inode is not visible to user space.
577 */
578 tmp_inode->i_blocks = 0;
579 EXT4_I(tmp_inode)->i_csum_seed = tmp_csum_seed;
580
581 /* Reset the extent details */
582 ext4_ext_tree_init(handle, tmp_inode);
583out_stop:
584 ext4_journal_stop(handle);
585out_tmp_inode:
586 unlock_new_inode(tmp_inode);
587 iput(tmp_inode);
588out_unlock:
589 ext4_writepages_up_write(inode->i_sb, alloc_ctx);
590 return retval;
591}
592
593/*
594 * Migrate a simple extent-based inode to use the i_blocks[] array
595 */
596int ext4_ind_migrate(struct inode *inode)
597{
598 struct ext4_extent_header *eh;
599 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
600 struct ext4_super_block *es = sbi->s_es;
601 struct ext4_inode_info *ei = EXT4_I(inode);
602 struct ext4_extent *ex;
603 unsigned int i, len;
604 ext4_lblk_t start, end;
605 ext4_fsblk_t blk;
606 handle_t *handle;
607 int ret, ret2 = 0;
608 int alloc_ctx;
609
610 if (!ext4_has_feature_extents(inode->i_sb) ||
611 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
612 return -EINVAL;
613
614 if (ext4_has_feature_bigalloc(inode->i_sb))
615 return -EOPNOTSUPP;
616
617 /*
618 * In order to get correct extent info, force all delayed allocation
619 * blocks to be allocated, otherwise delayed allocation blocks may not
620 * be reflected and bypass the checks on extent header.
621 */
622 if (test_opt(inode->i_sb, DELALLOC))
623 ext4_alloc_da_blocks(inode);
624
625 alloc_ctx = ext4_writepages_down_write(inode->i_sb);
626
627 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
628 if (IS_ERR(handle)) {
629 ret = PTR_ERR(handle);
630 goto out_unlock;
631 }
632
633 down_write(&EXT4_I(inode)->i_data_sem);
634 ret = ext4_ext_check_inode(inode);
635 if (ret)
636 goto errout;
637
638 eh = ext_inode_hdr(inode);
639 ex = EXT_FIRST_EXTENT(eh);
640 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
641 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
642 ret = -EOPNOTSUPP;
643 goto errout;
644 }
645 if (eh->eh_entries == 0)
646 blk = len = start = end = 0;
647 else {
648 len = le16_to_cpu(ex->ee_len);
649 blk = ext4_ext_pblock(ex);
650 start = le32_to_cpu(ex->ee_block);
651 end = start + len - 1;
652 if (end >= EXT4_NDIR_BLOCKS) {
653 ret = -EOPNOTSUPP;
654 goto errout;
655 }
656 }
657
658 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
659 memset(ei->i_data, 0, sizeof(ei->i_data));
660 for (i = start; i <= end; i++)
661 ei->i_data[i] = cpu_to_le32(blk++);
662 ret2 = ext4_mark_inode_dirty(handle, inode);
663 if (unlikely(ret2 && !ret))
664 ret = ret2;
665errout:
666 ext4_journal_stop(handle);
667 up_write(&EXT4_I(inode)->i_data_sem);
668out_unlock:
669 ext4_writepages_up_write(inode->i_sb, alloc_ctx);
670 return ret;
671}