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