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 */
16 struct migrate_struct {
17 ext4_lblk_t first_block, last_block, curr_block;
18 ext4_fsblk_t first_pblock, last_pblock;
19 };
20
finish_range(handle_t * handle,struct inode * inode,struct migrate_struct * lb)21 static int finish_range(handle_t *handle, struct inode *inode,
22 struct migrate_struct *lb)
23
24 {
25 int retval = 0, needed;
26 struct ext4_extent newext;
27 struct ext4_ext_path *path;
28 if (lb->first_pblock == 0)
29 return 0;
30
31 /* Add the extent to temp inode*/
32 newext.ee_block = cpu_to_le32(lb->first_block);
33 newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
34 ext4_ext_store_pblock(&newext, lb->first_pblock);
35 /* Locking only for convenience since we are operating on temp inode */
36 down_write(&EXT4_I(inode)->i_data_sem);
37 path = ext4_find_extent(inode, lb->first_block, NULL, 0);
38 if (IS_ERR(path)) {
39 retval = PTR_ERR(path);
40 goto err_out;
41 }
42
43 /*
44 * Calculate the credit needed to inserting this extent
45 * Since we are doing this in loop we may accumulate extra
46 * credit. But below we try to not accumulate too much
47 * of them by restarting the journal.
48 */
49 needed = ext4_ext_calc_credits_for_single_extent(inode,
50 lb->last_block - lb->first_block + 1, path);
51
52 retval = ext4_datasem_ensure_credits(handle, inode, needed, needed, 0);
53 if (retval < 0)
54 goto err_out;
55 path = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
56 if (IS_ERR(path))
57 retval = PTR_ERR(path);
58 err_out:
59 up_write((&EXT4_I(inode)->i_data_sem));
60 ext4_free_ext_path(path);
61 lb->first_pblock = 0;
62 return retval;
63 }
64
update_extent_range(handle_t * handle,struct inode * inode,ext4_fsblk_t pblock,struct migrate_struct * lb)65 static int update_extent_range(handle_t *handle, struct inode *inode,
66 ext4_fsblk_t pblock, struct migrate_struct *lb)
67 {
68 int retval;
69 /*
70 * See if we can add on to the existing range (if it exists)
71 */
72 if (lb->first_pblock &&
73 (lb->last_pblock+1 == pblock) &&
74 (lb->last_block+1 == lb->curr_block)) {
75 lb->last_pblock = pblock;
76 lb->last_block = lb->curr_block;
77 lb->curr_block++;
78 return 0;
79 }
80 /*
81 * Start a new range.
82 */
83 retval = finish_range(handle, inode, lb);
84 lb->first_pblock = lb->last_pblock = pblock;
85 lb->first_block = lb->last_block = lb->curr_block;
86 lb->curr_block++;
87 return retval;
88 }
89
update_ind_extent_range(handle_t * handle,struct inode * inode,ext4_fsblk_t pblock,struct migrate_struct * lb)90 static int update_ind_extent_range(handle_t *handle, struct inode *inode,
91 ext4_fsblk_t pblock,
92 struct migrate_struct *lb)
93 {
94 struct buffer_head *bh;
95 __le32 *i_data;
96 int i, retval = 0;
97 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
98
99 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
100 if (IS_ERR(bh))
101 return PTR_ERR(bh);
102
103 i_data = (__le32 *)bh->b_data;
104 for (i = 0; i < max_entries; i++) {
105 if (i_data[i]) {
106 retval = update_extent_range(handle, inode,
107 le32_to_cpu(i_data[i]), lb);
108 if (retval)
109 break;
110 } else {
111 lb->curr_block++;
112 }
113 }
114 put_bh(bh);
115 return retval;
116
117 }
118
update_dind_extent_range(handle_t * handle,struct inode * inode,ext4_fsblk_t pblock,struct migrate_struct * lb)119 static int update_dind_extent_range(handle_t *handle, struct inode *inode,
120 ext4_fsblk_t pblock,
121 struct migrate_struct *lb)
122 {
123 struct buffer_head *bh;
124 __le32 *i_data;
125 int i, retval = 0;
126 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
127
128 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
129 if (IS_ERR(bh))
130 return PTR_ERR(bh);
131
132 i_data = (__le32 *)bh->b_data;
133 for (i = 0; i < max_entries; i++) {
134 if (i_data[i]) {
135 retval = update_ind_extent_range(handle, inode,
136 le32_to_cpu(i_data[i]), lb);
137 if (retval)
138 break;
139 } else {
140 /* Only update the file block number */
141 lb->curr_block += max_entries;
142 }
143 }
144 put_bh(bh);
145 return retval;
146
147 }
148
update_tind_extent_range(handle_t * handle,struct inode * inode,ext4_fsblk_t pblock,struct migrate_struct * lb)149 static int update_tind_extent_range(handle_t *handle, struct inode *inode,
150 ext4_fsblk_t pblock,
151 struct migrate_struct *lb)
152 {
153 struct buffer_head *bh;
154 __le32 *i_data;
155 int i, retval = 0;
156 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
157
158 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
159 if (IS_ERR(bh))
160 return PTR_ERR(bh);
161
162 i_data = (__le32 *)bh->b_data;
163 for (i = 0; i < max_entries; i++) {
164 if (i_data[i]) {
165 retval = update_dind_extent_range(handle, inode,
166 le32_to_cpu(i_data[i]), lb);
167 if (retval)
168 break;
169 } else {
170 /* Only update the file block number */
171 lb->curr_block += max_entries * max_entries;
172 }
173 }
174 put_bh(bh);
175 return retval;
176
177 }
178
free_dind_blocks(handle_t * handle,struct inode * inode,__le32 i_data)179 static int free_dind_blocks(handle_t *handle,
180 struct inode *inode, __le32 i_data)
181 {
182 int i;
183 __le32 *tmp_idata;
184 struct buffer_head *bh;
185 struct super_block *sb = inode->i_sb;
186 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
187 int err;
188
189 bh = ext4_sb_bread(sb, le32_to_cpu(i_data), 0);
190 if (IS_ERR(bh))
191 return PTR_ERR(bh);
192
193 tmp_idata = (__le32 *)bh->b_data;
194 for (i = 0; i < max_entries; i++) {
195 if (tmp_idata[i]) {
196 err = ext4_journal_ensure_credits(handle,
197 EXT4_RESERVE_TRANS_BLOCKS,
198 ext4_free_metadata_revoke_credits(sb, 1));
199 if (err < 0) {
200 put_bh(bh);
201 return err;
202 }
203 ext4_free_blocks(handle, inode, NULL,
204 le32_to_cpu(tmp_idata[i]), 1,
205 EXT4_FREE_BLOCKS_METADATA |
206 EXT4_FREE_BLOCKS_FORGET);
207 }
208 }
209 put_bh(bh);
210 err = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
211 ext4_free_metadata_revoke_credits(sb, 1));
212 if (err < 0)
213 return err;
214 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
215 EXT4_FREE_BLOCKS_METADATA |
216 EXT4_FREE_BLOCKS_FORGET);
217 return 0;
218 }
219
free_tind_blocks(handle_t * handle,struct inode * inode,__le32 i_data)220 static int free_tind_blocks(handle_t *handle,
221 struct inode *inode, __le32 i_data)
222 {
223 int i, retval = 0;
224 __le32 *tmp_idata;
225 struct buffer_head *bh;
226 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
227
228 bh = ext4_sb_bread(inode->i_sb, le32_to_cpu(i_data), 0);
229 if (IS_ERR(bh))
230 return PTR_ERR(bh);
231
232 tmp_idata = (__le32 *)bh->b_data;
233 for (i = 0; i < max_entries; i++) {
234 if (tmp_idata[i]) {
235 retval = free_dind_blocks(handle,
236 inode, tmp_idata[i]);
237 if (retval) {
238 put_bh(bh);
239 return retval;
240 }
241 }
242 }
243 put_bh(bh);
244 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
245 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
246 if (retval < 0)
247 return retval;
248 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
249 EXT4_FREE_BLOCKS_METADATA |
250 EXT4_FREE_BLOCKS_FORGET);
251 return 0;
252 }
253
free_ind_block(handle_t * handle,struct inode * inode,__le32 * i_data)254 static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
255 {
256 int retval;
257
258 /* ei->i_data[EXT4_IND_BLOCK] */
259 if (i_data[0]) {
260 retval = ext4_journal_ensure_credits(handle,
261 EXT4_RESERVE_TRANS_BLOCKS,
262 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
263 if (retval < 0)
264 return retval;
265 ext4_free_blocks(handle, inode, NULL,
266 le32_to_cpu(i_data[0]), 1,
267 EXT4_FREE_BLOCKS_METADATA |
268 EXT4_FREE_BLOCKS_FORGET);
269 }
270
271 /* ei->i_data[EXT4_DIND_BLOCK] */
272 if (i_data[1]) {
273 retval = free_dind_blocks(handle, inode, i_data[1]);
274 if (retval)
275 return retval;
276 }
277
278 /* ei->i_data[EXT4_TIND_BLOCK] */
279 if (i_data[2]) {
280 retval = free_tind_blocks(handle, inode, i_data[2]);
281 if (retval)
282 return retval;
283 }
284 return 0;
285 }
286
ext4_ext_swap_inode_data(handle_t * handle,struct inode * inode,struct inode * tmp_inode)287 static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
288 struct inode *tmp_inode)
289 {
290 int retval, retval2 = 0;
291 __le32 i_data[3];
292 struct ext4_inode_info *ei = EXT4_I(inode);
293 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
294
295 /*
296 * One credit accounted for writing the
297 * i_data field of the original inode
298 */
299 retval = ext4_journal_ensure_credits(handle, 1, 0);
300 if (retval < 0)
301 goto err_out;
302
303 i_data[0] = ei->i_data[EXT4_IND_BLOCK];
304 i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
305 i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
306
307 down_write(&EXT4_I(inode)->i_data_sem);
308 /*
309 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
310 * happened after we started the migrate. We need to
311 * fail the migrate
312 */
313 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
314 retval = -EAGAIN;
315 up_write(&EXT4_I(inode)->i_data_sem);
316 goto err_out;
317 } else
318 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
319 /*
320 * We have the extent map build with the tmp inode.
321 * Now copy the i_data across
322 */
323 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
324 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
325
326 /*
327 * Update i_blocks with the new blocks that got
328 * allocated while adding extents for extent index
329 * blocks.
330 *
331 * While converting to extents we need not
332 * update the original inode i_blocks for extent blocks
333 * via quota APIs. The quota update happened via tmp_inode already.
334 */
335 spin_lock(&inode->i_lock);
336 inode->i_blocks += tmp_inode->i_blocks;
337 spin_unlock(&inode->i_lock);
338 up_write(&EXT4_I(inode)->i_data_sem);
339
340 /*
341 * We mark the inode dirty after, because we decrement the
342 * i_blocks when freeing the indirect meta-data blocks
343 */
344 retval = free_ind_block(handle, inode, i_data);
345 retval2 = ext4_mark_inode_dirty(handle, inode);
346 if (unlikely(retval2 && !retval))
347 retval = retval2;
348
349 err_out:
350 return retval;
351 }
352
free_ext_idx(handle_t * handle,struct inode * inode,struct ext4_extent_idx * ix)353 static int free_ext_idx(handle_t *handle, struct inode *inode,
354 struct ext4_extent_idx *ix)
355 {
356 int i, retval = 0;
357 ext4_fsblk_t block;
358 struct buffer_head *bh;
359 struct ext4_extent_header *eh;
360
361 block = ext4_idx_pblock(ix);
362 bh = ext4_sb_bread(inode->i_sb, block, 0);
363 if (IS_ERR(bh))
364 return PTR_ERR(bh);
365
366 eh = (struct ext4_extent_header *)bh->b_data;
367 if (eh->eh_depth != 0) {
368 ix = EXT_FIRST_INDEX(eh);
369 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
370 retval = free_ext_idx(handle, inode, ix);
371 if (retval) {
372 put_bh(bh);
373 return retval;
374 }
375 }
376 }
377 put_bh(bh);
378 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
379 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
380 if (retval < 0)
381 return retval;
382 ext4_free_blocks(handle, inode, NULL, block, 1,
383 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
384 return 0;
385 }
386
387 /*
388 * Free the extent meta data blocks only
389 */
free_ext_block(handle_t * handle,struct inode * inode)390 static int free_ext_block(handle_t *handle, struct inode *inode)
391 {
392 int i, retval = 0;
393 struct ext4_inode_info *ei = EXT4_I(inode);
394 struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
395 struct ext4_extent_idx *ix;
396 if (eh->eh_depth == 0)
397 /*
398 * No extra blocks allocated for extent meta data
399 */
400 return 0;
401 ix = EXT_FIRST_INDEX(eh);
402 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
403 retval = free_ext_idx(handle, inode, ix);
404 if (retval)
405 return retval;
406 }
407 return retval;
408 }
409
ext4_ext_migrate(struct inode * inode)410 int ext4_ext_migrate(struct inode *inode)
411 {
412 handle_t *handle;
413 int retval = 0, i;
414 __le32 *i_data;
415 struct ext4_inode_info *ei;
416 struct inode *tmp_inode = NULL;
417 struct migrate_struct lb;
418 unsigned long max_entries;
419 __u32 goal, tmp_csum_seed;
420 uid_t owner[2];
421 int alloc_ctx;
422
423 /*
424 * If the filesystem does not support extents, or the inode
425 * already is extent-based, error out.
426 */
427 if (!ext4_has_feature_extents(inode->i_sb) ||
428 ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) ||
429 ext4_has_inline_data(inode))
430 return -EINVAL;
431
432 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
433 /*
434 * don't migrate fast symlink
435 */
436 return retval;
437
438 alloc_ctx = ext4_writepages_down_write(inode->i_sb);
439
440 /*
441 * Worst case we can touch the allocation bitmaps and a block
442 * group descriptor block. We do need to worry about
443 * credits for modifying the quota inode.
444 */
445 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
446 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
447
448 if (IS_ERR(handle)) {
449 retval = PTR_ERR(handle);
450 goto out_unlock;
451 }
452 /*
453 * This operation rewrites the inode's block mapping layout
454 * (indirect to extents) and is not tracked in the fast commit
455 * log, so disable fast commits for this transaction.
456 */
457 ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_MIGRATE, handle);
458 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
459 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
460 owner[0] = i_uid_read(inode);
461 owner[1] = i_gid_read(inode);
462 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
463 S_IFREG, NULL, goal, owner, 0);
464 if (IS_ERR(tmp_inode)) {
465 retval = PTR_ERR(tmp_inode);
466 ext4_journal_stop(handle);
467 goto out_unlock;
468 }
469 /*
470 * Use the correct seed for checksum (i.e. the seed from 'inode'). This
471 * is so that the metadata blocks will have the correct checksum after
472 * the migration.
473 */
474 ei = EXT4_I(inode);
475 tmp_csum_seed = EXT4_I(tmp_inode)->i_csum_seed;
476 EXT4_I(tmp_inode)->i_csum_seed = ei->i_csum_seed;
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_journal_stop(handle);
486
487 /*
488 * start with one credit accounted for
489 * superblock modification.
490 *
491 * For the tmp_inode we already have committed the
492 * transaction that created the inode. Later as and
493 * when we add extents we extent the journal
494 */
495 /*
496 * Even though we take i_rwsem we can still cause block
497 * allocation via mmap write to holes. If we have allocated
498 * new blocks we fail migrate. New block allocation will
499 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
500 * with i_data_sem held to prevent racing with block
501 * allocation.
502 */
503 down_read(&EXT4_I(inode)->i_data_sem);
504 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
505 up_read((&EXT4_I(inode)->i_data_sem));
506
507 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
508 if (IS_ERR(handle)) {
509 retval = PTR_ERR(handle);
510 goto out_tmp_inode;
511 }
512
513 i_data = ei->i_data;
514 memset(&lb, 0, sizeof(lb));
515
516 /* 32 bit block address 4 bytes */
517 max_entries = inode->i_sb->s_blocksize >> 2;
518 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
519 if (i_data[i]) {
520 retval = update_extent_range(handle, tmp_inode,
521 le32_to_cpu(i_data[i]), &lb);
522 if (retval)
523 goto err_out;
524 } else
525 lb.curr_block++;
526 }
527 if (i_data[EXT4_IND_BLOCK]) {
528 retval = update_ind_extent_range(handle, tmp_inode,
529 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
530 if (retval)
531 goto err_out;
532 } else
533 lb.curr_block += max_entries;
534 if (i_data[EXT4_DIND_BLOCK]) {
535 retval = update_dind_extent_range(handle, tmp_inode,
536 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
537 if (retval)
538 goto err_out;
539 } else
540 lb.curr_block += max_entries * max_entries;
541 if (i_data[EXT4_TIND_BLOCK]) {
542 retval = update_tind_extent_range(handle, tmp_inode,
543 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
544 if (retval)
545 goto err_out;
546 }
547 /*
548 * Build the last extent
549 */
550 retval = finish_range(handle, tmp_inode, &lb);
551 err_out:
552 if (retval)
553 /*
554 * Failure case delete the extent information with the
555 * tmp_inode
556 */
557 free_ext_block(handle, tmp_inode);
558 else {
559 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
560 if (retval)
561 /*
562 * if we fail to swap inode data free the extent
563 * details of the tmp inode
564 */
565 free_ext_block(handle, tmp_inode);
566 }
567
568 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
569 retval = ext4_journal_ensure_credits(handle, 1, 0);
570 if (retval < 0)
571 goto out_stop;
572 /*
573 * Mark the tmp_inode as of size zero
574 */
575 i_size_write(tmp_inode, 0);
576
577 /*
578 * set the i_blocks count to zero
579 * so that the ext4_evict_inode() does the
580 * right job
581 *
582 * We don't need to take the i_lock because
583 * the inode is not visible to user space.
584 */
585 tmp_inode->i_blocks = 0;
586 EXT4_I(tmp_inode)->i_csum_seed = tmp_csum_seed;
587
588 /* Reset the extent details */
589 ext4_ext_tree_init(handle, tmp_inode);
590 out_stop:
591 ext4_journal_stop(handle);
592 out_tmp_inode:
593 unlock_new_inode(tmp_inode);
594 iput(tmp_inode);
595 out_unlock:
596 ext4_writepages_up_write(inode->i_sb, alloc_ctx);
597 return retval;
598 }
599
600 /*
601 * Migrate a simple extent-based inode to use the i_blocks[] array
602 */
ext4_ind_migrate(struct inode * inode)603 int ext4_ind_migrate(struct inode *inode)
604 {
605 struct ext4_extent_header *eh;
606 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
607 struct ext4_super_block *es = sbi->s_es;
608 struct ext4_inode_info *ei = EXT4_I(inode);
609 struct ext4_extent *ex;
610 unsigned int i, len;
611 ext4_lblk_t start, end;
612 ext4_fsblk_t blk;
613 handle_t *handle;
614 int ret, ret2 = 0;
615 int alloc_ctx;
616
617 if (!ext4_has_feature_extents(inode->i_sb) ||
618 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
619 return -EINVAL;
620
621 if (ext4_has_feature_bigalloc(inode->i_sb))
622 return -EOPNOTSUPP;
623
624 /*
625 * In order to get correct extent info, force all delayed allocation
626 * blocks to be allocated, otherwise delayed allocation blocks may not
627 * be reflected and bypass the checks on extent header.
628 */
629 if (test_opt(inode->i_sb, DELALLOC))
630 ext4_alloc_da_blocks(inode);
631
632 alloc_ctx = ext4_writepages_down_write(inode->i_sb);
633
634 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
635 if (IS_ERR(handle)) {
636 ret = PTR_ERR(handle);
637 goto out_unlock;
638 }
639 /*
640 * This operation rewrites the inode's block mapping layout
641 * (extents to indirect blocks) and is not tracked in the fast
642 * commit log, so disable fast commits for this transaction.
643 */
644 ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_MIGRATE, 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 ret2 = ext4_mark_inode_dirty(handle, inode);
676 if (unlikely(ret2 && !ret))
677 ret = ret2;
678 errout:
679 up_write(&EXT4_I(inode)->i_data_sem);
680 ext4_journal_stop(handle);
681 out_unlock:
682 ext4_writepages_up_write(inode->i_sb, alloc_ctx);
683 return ret;
684 }
685