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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/*
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 path = ext4_ext_find_extent(inode, lb->first_block, NULL, 0);
43
44 if (IS_ERR(path)) {
45 retval = PTR_ERR(path);
46 path = NULL;
47 goto err_out;
48 }
49
50 /*
51 * Calculate the credit needed to inserting this extent
52 * Since we are doing this in loop we may accumalate extra
53 * credit. But below we try to not accumalate too much
54 * of them by restarting the journal.
55 */
56 needed = ext4_ext_calc_credits_for_single_extent(inode,
57 lb->last_block - lb->first_block + 1, path);
58
59 /*
60 * Make sure the credit we accumalated is not really high
61 */
62 if (needed && ext4_handle_has_enough_credits(handle,
63 EXT4_RESERVE_TRANS_BLOCKS)) {
64 retval = ext4_journal_restart(handle, needed);
65 if (retval)
66 goto err_out;
67 } else if (needed) {
68 retval = ext4_journal_extend(handle, needed);
69 if (retval) {
70 /*
71 * IF not able to extend the journal restart the journal
72 */
73 retval = ext4_journal_restart(handle, needed);
74 if (retval)
75 goto err_out;
76 }
77 }
78 retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
79err_out:
80 if (path) {
81 ext4_ext_drop_refs(path);
82 kfree(path);
83 }
84 lb->first_pblock = 0;
85 return retval;
86}
87
88static int update_extent_range(handle_t *handle, struct inode *inode,
89 ext4_fsblk_t pblock, struct migrate_struct *lb)
90{
91 int retval;
92 /*
93 * See if we can add on to the existing range (if it exists)
94 */
95 if (lb->first_pblock &&
96 (lb->last_pblock+1 == pblock) &&
97 (lb->last_block+1 == lb->curr_block)) {
98 lb->last_pblock = pblock;
99 lb->last_block = lb->curr_block;
100 lb->curr_block++;
101 return 0;
102 }
103 /*
104 * Start a new range.
105 */
106 retval = finish_range(handle, inode, lb);
107 lb->first_pblock = lb->last_pblock = pblock;
108 lb->first_block = lb->last_block = lb->curr_block;
109 lb->curr_block++;
110 return retval;
111}
112
113static int update_ind_extent_range(handle_t *handle, struct inode *inode,
114 ext4_fsblk_t pblock,
115 struct migrate_struct *lb)
116{
117 struct buffer_head *bh;
118 __le32 *i_data;
119 int i, retval = 0;
120 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
121
122 bh = sb_bread(inode->i_sb, pblock);
123 if (!bh)
124 return -EIO;
125
126 i_data = (__le32 *)bh->b_data;
127 for (i = 0; i < max_entries; i++) {
128 if (i_data[i]) {
129 retval = update_extent_range(handle, inode,
130 le32_to_cpu(i_data[i]), lb);
131 if (retval)
132 break;
133 } else {
134 lb->curr_block++;
135 }
136 }
137 put_bh(bh);
138 return retval;
139
140}
141
142static int update_dind_extent_range(handle_t *handle, struct inode *inode,
143 ext4_fsblk_t pblock,
144 struct migrate_struct *lb)
145{
146 struct buffer_head *bh;
147 __le32 *i_data;
148 int i, retval = 0;
149 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
150
151 bh = sb_bread(inode->i_sb, pblock);
152 if (!bh)
153 return -EIO;
154
155 i_data = (__le32 *)bh->b_data;
156 for (i = 0; i < max_entries; i++) {
157 if (i_data[i]) {
158 retval = update_ind_extent_range(handle, inode,
159 le32_to_cpu(i_data[i]), lb);
160 if (retval)
161 break;
162 } else {
163 /* Only update the file block number */
164 lb->curr_block += max_entries;
165 }
166 }
167 put_bh(bh);
168 return retval;
169
170}
171
172static int update_tind_extent_range(handle_t *handle, struct inode *inode,
173 ext4_fsblk_t pblock,
174 struct migrate_struct *lb)
175{
176 struct buffer_head *bh;
177 __le32 *i_data;
178 int i, retval = 0;
179 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
180
181 bh = sb_bread(inode->i_sb, pblock);
182 if (!bh)
183 return -EIO;
184
185 i_data = (__le32 *)bh->b_data;
186 for (i = 0; i < max_entries; i++) {
187 if (i_data[i]) {
188 retval = update_dind_extent_range(handle, inode,
189 le32_to_cpu(i_data[i]), lb);
190 if (retval)
191 break;
192 } else {
193 /* Only update the file block number */
194 lb->curr_block += max_entries * max_entries;
195 }
196 }
197 put_bh(bh);
198 return retval;
199
200}
201
202static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
203{
204 int retval = 0, needed;
205
206 if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
207 return 0;
208 /*
209 * We are freeing a blocks. During this we touch
210 * superblock, group descriptor and block bitmap.
211 * So allocate a credit of 3. We may update
212 * quota (user and group).
213 */
214 needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
215
216 if (ext4_journal_extend(handle, needed) != 0)
217 retval = ext4_journal_restart(handle, needed);
218
219 return retval;
220}
221
222static int free_dind_blocks(handle_t *handle,
223 struct inode *inode, __le32 i_data)
224{
225 int i;
226 __le32 *tmp_idata;
227 struct buffer_head *bh;
228 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
229
230 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
231 if (!bh)
232 return -EIO;
233
234 tmp_idata = (__le32 *)bh->b_data;
235 for (i = 0; i < max_entries; i++) {
236 if (tmp_idata[i]) {
237 extend_credit_for_blkdel(handle, inode);
238 ext4_free_blocks(handle, inode, NULL,
239 le32_to_cpu(tmp_idata[i]), 1,
240 EXT4_FREE_BLOCKS_METADATA |
241 EXT4_FREE_BLOCKS_FORGET);
242 }
243 }
244 put_bh(bh);
245 extend_credit_for_blkdel(handle, inode);
246 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
247 EXT4_FREE_BLOCKS_METADATA |
248 EXT4_FREE_BLOCKS_FORGET);
249 return 0;
250}
251
252static int free_tind_blocks(handle_t *handle,
253 struct inode *inode, __le32 i_data)
254{
255 int i, retval = 0;
256 __le32 *tmp_idata;
257 struct buffer_head *bh;
258 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
259
260 bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
261 if (!bh)
262 return -EIO;
263
264 tmp_idata = (__le32 *)bh->b_data;
265 for (i = 0; i < max_entries; i++) {
266 if (tmp_idata[i]) {
267 retval = free_dind_blocks(handle,
268 inode, tmp_idata[i]);
269 if (retval) {
270 put_bh(bh);
271 return retval;
272 }
273 }
274 }
275 put_bh(bh);
276 extend_credit_for_blkdel(handle, inode);
277 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
278 EXT4_FREE_BLOCKS_METADATA |
279 EXT4_FREE_BLOCKS_FORGET);
280 return 0;
281}
282
283static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
284{
285 int retval;
286
287 /* ei->i_data[EXT4_IND_BLOCK] */
288 if (i_data[0]) {
289 extend_credit_for_blkdel(handle, inode);
290 ext4_free_blocks(handle, inode, NULL,
291 le32_to_cpu(i_data[0]), 1,
292 EXT4_FREE_BLOCKS_METADATA |
293 EXT4_FREE_BLOCKS_FORGET);
294 }
295
296 /* ei->i_data[EXT4_DIND_BLOCK] */
297 if (i_data[1]) {
298 retval = free_dind_blocks(handle, inode, i_data[1]);
299 if (retval)
300 return retval;
301 }
302
303 /* ei->i_data[EXT4_TIND_BLOCK] */
304 if (i_data[2]) {
305 retval = free_tind_blocks(handle, inode, i_data[2]);
306 if (retval)
307 return retval;
308 }
309 return 0;
310}
311
312static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
313 struct inode *tmp_inode)
314{
315 int retval;
316 __le32 i_data[3];
317 struct ext4_inode_info *ei = EXT4_I(inode);
318 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
319
320 /*
321 * One credit accounted for writing the
322 * i_data field of the original inode
323 */
324 retval = ext4_journal_extend(handle, 1);
325 if (retval) {
326 retval = ext4_journal_restart(handle, 1);
327 if (retval)
328 goto err_out;
329 }
330
331 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
332 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
333 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
334
335 down_write(&EXT4_I(inode)->i_data_sem);
336 /*
337 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
338 * happened after we started the migrate. We need to
339 * fail the migrate
340 */
341 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
342 retval = -EAGAIN;
343 up_write(&EXT4_I(inode)->i_data_sem);
344 goto err_out;
345 } else
346 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
347 /*
348 * We have the extent map build with the tmp inode.
349 * Now copy the i_data across
350 */
351 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
352 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
353
354 /*
355 * Update i_blocks with the new blocks that got
356 * allocated while adding extents for extent index
357 * blocks.
358 *
359 * While converting to extents we need not
360 * update the orignal inode i_blocks for extent blocks
361 * via quota APIs. The quota update happened via tmp_inode already.
362 */
363 spin_lock(&inode->i_lock);
364 inode->i_blocks += tmp_inode->i_blocks;
365 spin_unlock(&inode->i_lock);
366 up_write(&EXT4_I(inode)->i_data_sem);
367
368 /*
369 * We mark the inode dirty after, because we decrement the
370 * i_blocks when freeing the indirect meta-data blocks
371 */
372 retval = free_ind_block(handle, inode, i_data);
373 ext4_mark_inode_dirty(handle, inode);
374
375err_out:
376 return retval;
377}
378
379static int free_ext_idx(handle_t *handle, struct inode *inode,
380 struct ext4_extent_idx *ix)
381{
382 int i, retval = 0;
383 ext4_fsblk_t block;
384 struct buffer_head *bh;
385 struct ext4_extent_header *eh;
386
387 block = ext4_idx_pblock(ix);
388 bh = sb_bread(inode->i_sb, block);
389 if (!bh)
390 return -EIO;
391
392 eh = (struct ext4_extent_header *)bh->b_data;
393 if (eh->eh_depth != 0) {
394 ix = EXT_FIRST_INDEX(eh);
395 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
396 retval = free_ext_idx(handle, inode, ix);
397 if (retval)
398 break;
399 }
400 }
401 put_bh(bh);
402 extend_credit_for_blkdel(handle, inode);
403 ext4_free_blocks(handle, inode, NULL, block, 1,
404 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
405 return retval;
406}
407
408/*
409 * Free the extent meta data blocks only
410 */
411static int free_ext_block(handle_t *handle, struct inode *inode)
412{
413 int i, retval = 0;
414 struct ext4_inode_info *ei = EXT4_I(inode);
415 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
416 struct ext4_extent_idx *ix;
417 if (eh->eh_depth == 0)
418 /*
419 * No extra blocks allocated for extent meta data
420 */
421 return 0;
422 ix = EXT_FIRST_INDEX(eh);
423 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
424 retval = free_ext_idx(handle, inode, ix);
425 if (retval)
426 return retval;
427 }
428 return retval;
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 /*
459 * Worst case we can touch the allocation bitmaps, a bgd
460 * block, and a block to link in the orphan list. We do need
461 * need to worry about credits for modifying the quota inode.
462 */
463 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
464 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
465
466 if (IS_ERR(handle)) {
467 retval = PTR_ERR(handle);
468 return retval;
469 }
470 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
471 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
472 owner[0] = i_uid_read(inode);
473 owner[1] = i_gid_read(inode);
474 tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
475 S_IFREG, NULL, goal, owner);
476 if (IS_ERR(tmp_inode)) {
477 retval = PTR_ERR(tmp_inode);
478 ext4_journal_stop(handle);
479 return retval;
480 }
481 i_size_write(tmp_inode, i_size_read(inode));
482 /*
483 * Set the i_nlink to zero so it will be deleted later
484 * when we drop inode reference.
485 */
486 clear_nlink(tmp_inode);
487
488 ext4_ext_tree_init(handle, tmp_inode);
489 ext4_orphan_add(handle, tmp_inode);
490 ext4_journal_stop(handle);
491
492 /*
493 * start with one credit accounted for
494 * superblock modification.
495 *
496 * For the tmp_inode we already have committed the
497 * transaction that created the inode. Later as and
498 * when we add extents we extent the journal
499 */
500 /*
501 * Even though we take i_mutex we can still cause block
502 * allocation via mmap write to holes. If we have allocated
503 * new blocks we fail migrate. New block allocation will
504 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
505 * with i_data_sem held to prevent racing with block
506 * allocation.
507 */
508 down_read((&EXT4_I(inode)->i_data_sem));
509 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
510 up_read((&EXT4_I(inode)->i_data_sem));
511
512 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
513 if (IS_ERR(handle)) {
514 /*
515 * It is impossible to update on-disk structures without
516 * a handle, so just rollback in-core changes and live other
517 * work to orphan_list_cleanup()
518 */
519 ext4_orphan_del(NULL, tmp_inode);
520 retval = PTR_ERR(handle);
521 goto out;
522 }
523
524 ei = EXT4_I(inode);
525 i_data = ei->i_data;
526 memset(&lb, 0, sizeof(lb));
527
528 /* 32 bit block address 4 bytes */
529 max_entries = inode->i_sb->s_blocksize >> 2;
530 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
531 if (i_data[i]) {
532 retval = update_extent_range(handle, tmp_inode,
533 le32_to_cpu(i_data[i]), &lb);
534 if (retval)
535 goto err_out;
536 } else
537 lb.curr_block++;
538 }
539 if (i_data[EXT4_IND_BLOCK]) {
540 retval = update_ind_extent_range(handle, tmp_inode,
541 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
542 if (retval)
543 goto err_out;
544 } else
545 lb.curr_block += max_entries;
546 if (i_data[EXT4_DIND_BLOCK]) {
547 retval = update_dind_extent_range(handle, tmp_inode,
548 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
549 if (retval)
550 goto err_out;
551 } else
552 lb.curr_block += max_entries * max_entries;
553 if (i_data[EXT4_TIND_BLOCK]) {
554 retval = update_tind_extent_range(handle, tmp_inode,
555 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
556 if (retval)
557 goto err_out;
558 }
559 /*
560 * Build the last extent
561 */
562 retval = finish_range(handle, tmp_inode, &lb);
563err_out:
564 if (retval)
565 /*
566 * Failure case delete the extent information with the
567 * tmp_inode
568 */
569 free_ext_block(handle, tmp_inode);
570 else {
571 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
572 if (retval)
573 /*
574 * if we fail to swap inode data free the extent
575 * details of the tmp inode
576 */
577 free_ext_block(handle, tmp_inode);
578 }
579
580 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
581 if (ext4_journal_extend(handle, 1) != 0)
582 ext4_journal_restart(handle, 1);
583
584 /*
585 * Mark the tmp_inode as of size zero
586 */
587 i_size_write(tmp_inode, 0);
588
589 /*
590 * set the i_blocks count to zero
591 * so that the ext4_delete_inode does the
592 * right job
593 *
594 * We don't need to take the i_lock because
595 * the inode is not visible to user space.
596 */
597 tmp_inode->i_blocks = 0;
598
599 /* Reset the extent details */
600 ext4_ext_tree_init(handle, tmp_inode);
601 ext4_journal_stop(handle);
602out:
603 unlock_new_inode(tmp_inode);
604 iput(tmp_inode);
605
606 return retval;
607}
608
609/*
610 * Migrate a simple extent-based inode to use the i_blocks[] array
611 */
612int ext4_ind_migrate(struct inode *inode)
613{
614 struct ext4_extent_header *eh;
615 struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
616 struct ext4_inode_info *ei = EXT4_I(inode);
617 struct ext4_extent *ex;
618 unsigned int i, len;
619 ext4_fsblk_t blk;
620 handle_t *handle;
621 int ret;
622
623 if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
624 EXT4_FEATURE_INCOMPAT_EXTENTS) ||
625 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
626 return -EINVAL;
627
628 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
629 EXT4_FEATURE_RO_COMPAT_BIGALLOC))
630 return -EOPNOTSUPP;
631
632 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
633 if (IS_ERR(handle))
634 return PTR_ERR(handle);
635
636 down_write(&EXT4_I(inode)->i_data_sem);
637 ret = ext4_ext_check_inode(inode);
638 if (ret)
639 goto errout;
640
641 eh = ext_inode_hdr(inode);
642 ex = EXT_FIRST_EXTENT(eh);
643 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
644 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
645 ret = -EOPNOTSUPP;
646 goto errout;
647 }
648 if (eh->eh_entries == 0)
649 blk = len = 0;
650 else {
651 len = le16_to_cpu(ex->ee_len);
652 blk = ext4_ext_pblock(ex);
653 if (len > 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=0; i < len; i++)
662 ei->i_data[i] = cpu_to_le32(blk++);
663 ext4_mark_inode_dirty(handle, inode);
664errout:
665 ext4_journal_stop(handle);
666 up_write(&EXT4_I(inode)->i_data_sem);
667 return ret;
668}