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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/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}
1// SPDX-License-Identifier: LGPL-2.1
2/*
3 * Copyright IBM Corporation, 2007
4 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
5 *
6 */
7
8#include <linux/slab.h>
9#include "ext4_jbd2.h"
10#include "ext4_extents.h"
11
12/*
13 * The contiguous blocks details which can be
14 * represented by a single extent
15 */
16struct migrate_struct {
17 ext4_lblk_t first_block, last_block, curr_block;
18 ext4_fsblk_t first_pblock, last_pblock;
19};
20
21static int finish_range(handle_t *handle, struct inode *inode,
22 struct migrate_struct *lb)
23
24{
25 int retval = 0, needed;
26 struct ext4_extent newext;
27 struct ext4_ext_path *path;
28 if (lb->first_pblock == 0)
29 return 0;
30
31 /* Add the extent to temp inode*/
32 newext.ee_block = cpu_to_le32(lb->first_block);
33 newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
34 ext4_ext_store_pblock(&newext, lb->first_pblock);
35 /* Locking only for convinience since we are operating on temp inode */
36 down_write(&EXT4_I(inode)->i_data_sem);
37 path = ext4_find_extent(inode, lb->first_block, NULL, 0);
38 if (IS_ERR(path)) {
39 retval = PTR_ERR(path);
40 path = NULL;
41 goto err_out;
42 }
43
44 /*
45 * Calculate the credit needed to inserting this extent
46 * Since we are doing this in loop we may accumalate extra
47 * credit. But below we try to not accumalate too much
48 * of them by restarting the journal.
49 */
50 needed = ext4_ext_calc_credits_for_single_extent(inode,
51 lb->last_block - lb->first_block + 1, path);
52
53 /*
54 * Make sure the credit we accumalated is not really high
55 */
56 if (needed && ext4_handle_has_enough_credits(handle,
57 EXT4_RESERVE_TRANS_BLOCKS)) {
58 up_write((&EXT4_I(inode)->i_data_sem));
59 retval = ext4_journal_restart(handle, needed);
60 down_write((&EXT4_I(inode)->i_data_sem));
61 if (retval)
62 goto err_out;
63 } else if (needed) {
64 retval = ext4_journal_extend(handle, needed);
65 if (retval) {
66 /*
67 * IF not able to extend the journal restart the journal
68 */
69 up_write((&EXT4_I(inode)->i_data_sem));
70 retval = ext4_journal_restart(handle, needed);
71 down_write((&EXT4_I(inode)->i_data_sem));
72 if (retval)
73 goto err_out;
74 }
75 }
76 retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
77err_out:
78 up_write((&EXT4_I(inode)->i_data_sem));
79 ext4_ext_drop_refs(path);
80 kfree(path);
81 lb->first_pblock = 0;
82 return retval;
83}
84
85static int update_extent_range(handle_t *handle, struct inode *inode,
86 ext4_fsblk_t pblock, struct migrate_struct *lb)
87{
88 int retval;
89 /*
90 * See if we can add on to the existing range (if it exists)
91 */
92 if (lb->first_pblock &&
93 (lb->last_pblock+1 == pblock) &&
94 (lb->last_block+1 == lb->curr_block)) {
95 lb->last_pblock = pblock;
96 lb->last_block = lb->curr_block;
97 lb->curr_block++;
98 return 0;
99 }
100 /*
101 * Start a new range.
102 */
103 retval = finish_range(handle, inode, lb);
104 lb->first_pblock = lb->last_pblock = pblock;
105 lb->first_block = lb->last_block = lb->curr_block;
106 lb->curr_block++;
107 return retval;
108}
109
110static int update_ind_extent_range(handle_t *handle, struct inode *inode,
111 ext4_fsblk_t pblock,
112 struct migrate_struct *lb)
113{
114 struct buffer_head *bh;
115 __le32 *i_data;
116 int i, retval = 0;
117 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
118
119 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
120 if (IS_ERR(bh))
121 return PTR_ERR(bh);
122
123 i_data = (__le32 *)bh->b_data;
124 for (i = 0; i < max_entries; i++) {
125 if (i_data[i]) {
126 retval = update_extent_range(handle, inode,
127 le32_to_cpu(i_data[i]), lb);
128 if (retval)
129 break;
130 } else {
131 lb->curr_block++;
132 }
133 }
134 put_bh(bh);
135 return retval;
136
137}
138
139static int update_dind_extent_range(handle_t *handle, struct inode *inode,
140 ext4_fsblk_t pblock,
141 struct migrate_struct *lb)
142{
143 struct buffer_head *bh;
144 __le32 *i_data;
145 int i, retval = 0;
146 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
147
148 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
149 if (IS_ERR(bh))
150 return PTR_ERR(bh);
151
152 i_data = (__le32 *)bh->b_data;
153 for (i = 0; i < max_entries; i++) {
154 if (i_data[i]) {
155 retval = update_ind_extent_range(handle, inode,
156 le32_to_cpu(i_data[i]), lb);
157 if (retval)
158 break;
159 } else {
160 /* Only update the file block number */
161 lb->curr_block += max_entries;
162 }
163 }
164 put_bh(bh);
165 return retval;
166
167}
168
169static int update_tind_extent_range(handle_t *handle, struct inode *inode,
170 ext4_fsblk_t pblock,
171 struct migrate_struct *lb)
172{
173 struct buffer_head *bh;
174 __le32 *i_data;
175 int i, retval = 0;
176 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
177
178 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
179 if (IS_ERR(bh))
180 return PTR_ERR(bh);
181
182 i_data = (__le32 *)bh->b_data;
183 for (i = 0; i < max_entries; i++) {
184 if (i_data[i]) {
185 retval = update_dind_extent_range(handle, inode,
186 le32_to_cpu(i_data[i]), lb);
187 if (retval)
188 break;
189 } else {
190 /* Only update the file block number */
191 lb->curr_block += max_entries * max_entries;
192 }
193 }
194 put_bh(bh);
195 return retval;
196
197}
198
199static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
200{
201 int retval = 0, needed;
202
203 if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
204 return 0;
205 /*
206 * We are freeing a blocks. During this we touch
207 * superblock, group descriptor and block bitmap.
208 * So allocate a credit of 3. We may update
209 * quota (user and group).
210 */
211 needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
212
213 if (ext4_journal_extend(handle, needed) != 0)
214 retval = ext4_journal_restart(handle, needed);
215
216 return retval;
217}
218
219static int free_dind_blocks(handle_t *handle,
220 struct inode *inode, __le32 i_data)
221{
222 int i;
223 __le32 *tmp_idata;
224 struct buffer_head *bh;
225 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
226
227 bh = 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 extend_credit_for_blkdel(handle, inode);
235 ext4_free_blocks(handle, inode, NULL,
236 le32_to_cpu(tmp_idata[i]), 1,
237 EXT4_FREE_BLOCKS_METADATA |
238 EXT4_FREE_BLOCKS_FORGET);
239 }
240 }
241 put_bh(bh);
242 extend_credit_for_blkdel(handle, inode);
243 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
244 EXT4_FREE_BLOCKS_METADATA |
245 EXT4_FREE_BLOCKS_FORGET);
246 return 0;
247}
248
249static int free_tind_blocks(handle_t *handle,
250 struct inode *inode, __le32 i_data)
251{
252 int i, retval = 0;
253 __le32 *tmp_idata;
254 struct buffer_head *bh;
255 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
256
257 bh = ext4_sb_bread(inode->i_sb, le32_to_cpu(i_data), 0);
258 if (IS_ERR(bh))
259 return PTR_ERR(bh);
260
261 tmp_idata = (__le32 *)bh->b_data;
262 for (i = 0; i < max_entries; i++) {
263 if (tmp_idata[i]) {
264 retval = free_dind_blocks(handle,
265 inode, tmp_idata[i]);
266 if (retval) {
267 put_bh(bh);
268 return retval;
269 }
270 }
271 }
272 put_bh(bh);
273 extend_credit_for_blkdel(handle, inode);
274 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
275 EXT4_FREE_BLOCKS_METADATA |
276 EXT4_FREE_BLOCKS_FORGET);
277 return 0;
278}
279
280static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
281{
282 int retval;
283
284 /* ei->i_data[EXT4_IND_BLOCK] */
285 if (i_data[0]) {
286 extend_credit_for_blkdel(handle, inode);
287 ext4_free_blocks(handle, inode, NULL,
288 le32_to_cpu(i_data[0]), 1,
289 EXT4_FREE_BLOCKS_METADATA |
290 EXT4_FREE_BLOCKS_FORGET);
291 }
292
293 /* ei->i_data[EXT4_DIND_BLOCK] */
294 if (i_data[1]) {
295 retval = free_dind_blocks(handle, inode, i_data[1]);
296 if (retval)
297 return retval;
298 }
299
300 /* ei->i_data[EXT4_TIND_BLOCK] */
301 if (i_data[2]) {
302 retval = free_tind_blocks(handle, inode, i_data[2]);
303 if (retval)
304 return retval;
305 }
306 return 0;
307}
308
309static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
310 struct inode *tmp_inode)
311{
312 int retval;
313 __le32 i_data[3];
314 struct ext4_inode_info *ei = EXT4_I(inode);
315 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
316
317 /*
318 * One credit accounted for writing the
319 * i_data field of the original inode
320 */
321 retval = ext4_journal_extend(handle, 1);
322 if (retval) {
323 retval = ext4_journal_restart(handle, 1);
324 if (retval)
325 goto err_out;
326 }
327
328 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
329 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
330 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
331
332 down_write(&EXT4_I(inode)->i_data_sem);
333 /*
334 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
335 * happened after we started the migrate. We need to
336 * fail the migrate
337 */
338 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
339 retval = -EAGAIN;
340 up_write(&EXT4_I(inode)->i_data_sem);
341 goto err_out;
342 } else
343 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
344 /*
345 * We have the extent map build with the tmp inode.
346 * Now copy the i_data across
347 */
348 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
349 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
350
351 /*
352 * Update i_blocks with the new blocks that got
353 * allocated while adding extents for extent index
354 * blocks.
355 *
356 * While converting to extents we need not
357 * update the original inode i_blocks for extent blocks
358 * via quota APIs. The quota update happened via tmp_inode already.
359 */
360 spin_lock(&inode->i_lock);
361 inode->i_blocks += tmp_inode->i_blocks;
362 spin_unlock(&inode->i_lock);
363 up_write(&EXT4_I(inode)->i_data_sem);
364
365 /*
366 * We mark the inode dirty after, because we decrement the
367 * i_blocks when freeing the indirect meta-data blocks
368 */
369 retval = free_ind_block(handle, inode, i_data);
370 ext4_mark_inode_dirty(handle, inode);
371
372err_out:
373 return retval;
374}
375
376static int free_ext_idx(handle_t *handle, struct inode *inode,
377 struct ext4_extent_idx *ix)
378{
379 int i, retval = 0;
380 ext4_fsblk_t block;
381 struct buffer_head *bh;
382 struct ext4_extent_header *eh;
383
384 block = ext4_idx_pblock(ix);
385 bh = ext4_sb_bread(inode->i_sb, block, 0);
386 if (IS_ERR(bh))
387 return PTR_ERR(bh);
388
389 eh = (struct ext4_extent_header *)bh->b_data;
390 if (eh->eh_depth != 0) {
391 ix = EXT_FIRST_INDEX(eh);
392 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
393 retval = free_ext_idx(handle, inode, ix);
394 if (retval)
395 break;
396 }
397 }
398 put_bh(bh);
399 extend_credit_for_blkdel(handle, inode);
400 ext4_free_blocks(handle, inode, NULL, block, 1,
401 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
402 return retval;
403}
404
405/*
406 * Free the extent meta data blocks only
407 */
408static int free_ext_block(handle_t *handle, struct inode *inode)
409{
410 int i, retval = 0;
411 struct ext4_inode_info *ei = EXT4_I(inode);
412 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
413 struct ext4_extent_idx *ix;
414 if (eh->eh_depth == 0)
415 /*
416 * No extra blocks allocated for extent meta data
417 */
418 return 0;
419 ix = EXT_FIRST_INDEX(eh);
420 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
421 retval = free_ext_idx(handle, inode, ix);
422 if (retval)
423 return retval;
424 }
425 return retval;
426}
427
428int ext4_ext_migrate(struct inode *inode)
429{
430 handle_t *handle;
431 int retval = 0, i;
432 __le32 *i_data;
433 struct ext4_inode_info *ei;
434 struct inode *tmp_inode = NULL;
435 struct migrate_struct lb;
436 unsigned long max_entries;
437 __u32 goal;
438 uid_t owner[2];
439
440 /*
441 * If the filesystem does not support extents, or the inode
442 * already is extent-based, error out.
443 */
444 if (!ext4_has_feature_extents(inode->i_sb) ||
445 (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
446 return -EINVAL;
447
448 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
449 /*
450 * don't migrate fast symlink
451 */
452 return retval;
453
454 /*
455 * Worst case we can touch the allocation bitmaps, a bgd
456 * block, and a block to link in the orphan list. We do need
457 * need to worry about credits for modifying the quota inode.
458 */
459 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
460 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
461
462 if (IS_ERR(handle)) {
463 retval = PTR_ERR(handle);
464 return retval;
465 }
466 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
467 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
468 owner[0] = i_uid_read(inode);
469 owner[1] = i_gid_read(inode);
470 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
471 S_IFREG, NULL, goal, owner, 0);
472 if (IS_ERR(tmp_inode)) {
473 retval = PTR_ERR(tmp_inode);
474 ext4_journal_stop(handle);
475 return retval;
476 }
477 i_size_write(tmp_inode, i_size_read(inode));
478 /*
479 * Set the i_nlink to zero so it will be deleted later
480 * when we drop inode reference.
481 */
482 clear_nlink(tmp_inode);
483
484 ext4_ext_tree_init(handle, tmp_inode);
485 ext4_orphan_add(handle, tmp_inode);
486 ext4_journal_stop(handle);
487
488 /*
489 * start with one credit accounted for
490 * superblock modification.
491 *
492 * For the tmp_inode we already have committed the
493 * transaction that created the inode. Later as and
494 * when we add extents we extent the journal
495 */
496 /*
497 * Even though we take i_mutex we can still cause block
498 * allocation via mmap write to holes. If we have allocated
499 * new blocks we fail migrate. New block allocation will
500 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
501 * with i_data_sem held to prevent racing with block
502 * allocation.
503 */
504 down_read(&EXT4_I(inode)->i_data_sem);
505 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
506 up_read((&EXT4_I(inode)->i_data_sem));
507
508 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
509 if (IS_ERR(handle)) {
510 /*
511 * It is impossible to update on-disk structures without
512 * a handle, so just rollback in-core changes and live other
513 * work to orphan_list_cleanup()
514 */
515 ext4_orphan_del(NULL, tmp_inode);
516 retval = PTR_ERR(handle);
517 goto out;
518 }
519
520 ei = EXT4_I(inode);
521 i_data = ei->i_data;
522 memset(&lb, 0, sizeof(lb));
523
524 /* 32 bit block address 4 bytes */
525 max_entries = inode->i_sb->s_blocksize >> 2;
526 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
527 if (i_data[i]) {
528 retval = update_extent_range(handle, tmp_inode,
529 le32_to_cpu(i_data[i]), &lb);
530 if (retval)
531 goto err_out;
532 } else
533 lb.curr_block++;
534 }
535 if (i_data[EXT4_IND_BLOCK]) {
536 retval = update_ind_extent_range(handle, tmp_inode,
537 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
538 if (retval)
539 goto err_out;
540 } else
541 lb.curr_block += max_entries;
542 if (i_data[EXT4_DIND_BLOCK]) {
543 retval = update_dind_extent_range(handle, tmp_inode,
544 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
545 if (retval)
546 goto err_out;
547 } else
548 lb.curr_block += max_entries * max_entries;
549 if (i_data[EXT4_TIND_BLOCK]) {
550 retval = update_tind_extent_range(handle, tmp_inode,
551 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
552 if (retval)
553 goto err_out;
554 }
555 /*
556 * Build the last extent
557 */
558 retval = finish_range(handle, tmp_inode, &lb);
559err_out:
560 if (retval)
561 /*
562 * Failure case delete the extent information with the
563 * tmp_inode
564 */
565 free_ext_block(handle, tmp_inode);
566 else {
567 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
568 if (retval)
569 /*
570 * if we fail to swap inode data free the extent
571 * details of the tmp inode
572 */
573 free_ext_block(handle, tmp_inode);
574 }
575
576 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
577 if (ext4_journal_extend(handle, 1) != 0)
578 ext4_journal_restart(handle, 1);
579
580 /*
581 * Mark the tmp_inode as of size zero
582 */
583 i_size_write(tmp_inode, 0);
584
585 /*
586 * set the i_blocks count to zero
587 * so that the ext4_evict_inode() does the
588 * right job
589 *
590 * We don't need to take the i_lock because
591 * the inode is not visible to user space.
592 */
593 tmp_inode->i_blocks = 0;
594
595 /* Reset the extent details */
596 ext4_ext_tree_init(handle, tmp_inode);
597 ext4_journal_stop(handle);
598out:
599 unlock_new_inode(tmp_inode);
600 iput(tmp_inode);
601
602 return retval;
603}
604
605/*
606 * Migrate a simple extent-based inode to use the i_blocks[] array
607 */
608int ext4_ind_migrate(struct inode *inode)
609{
610 struct ext4_extent_header *eh;
611 struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
612 struct ext4_inode_info *ei = EXT4_I(inode);
613 struct ext4_extent *ex;
614 unsigned int i, len;
615 ext4_lblk_t start, end;
616 ext4_fsblk_t blk;
617 handle_t *handle;
618 int ret;
619
620 if (!ext4_has_feature_extents(inode->i_sb) ||
621 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
622 return -EINVAL;
623
624 if (ext4_has_feature_bigalloc(inode->i_sb))
625 return -EOPNOTSUPP;
626
627 /*
628 * In order to get correct extent info, force all delayed allocation
629 * blocks to be allocated, otherwise delayed allocation blocks may not
630 * be reflected and bypass the checks on extent header.
631 */
632 if (test_opt(inode->i_sb, DELALLOC))
633 ext4_alloc_da_blocks(inode);
634
635 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
636 if (IS_ERR(handle))
637 return PTR_ERR(handle);
638
639 down_write(&EXT4_I(inode)->i_data_sem);
640 ret = ext4_ext_check_inode(inode);
641 if (ret)
642 goto errout;
643
644 eh = ext_inode_hdr(inode);
645 ex = EXT_FIRST_EXTENT(eh);
646 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
647 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
648 ret = -EOPNOTSUPP;
649 goto errout;
650 }
651 if (eh->eh_entries == 0)
652 blk = len = start = end = 0;
653 else {
654 len = le16_to_cpu(ex->ee_len);
655 blk = ext4_ext_pblock(ex);
656 start = le32_to_cpu(ex->ee_block);
657 end = start + len - 1;
658 if (end >= EXT4_NDIR_BLOCKS) {
659 ret = -EOPNOTSUPP;
660 goto errout;
661 }
662 }
663
664 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
665 memset(ei->i_data, 0, sizeof(ei->i_data));
666 for (i = start; i <= end; i++)
667 ei->i_data[i] = cpu_to_le32(blk++);
668 ext4_mark_inode_dirty(handle, inode);
669errout:
670 ext4_journal_stop(handle);
671 up_write(&EXT4_I(inode)->i_data_sem);
672 return ret;
673}