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