2 * Copyright IBM Corporation, 2007
3 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
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.
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.
15 #include <linux/slab.h>
16 #include "ext4_jbd2.h"
17 #include "ext4_extents.h"
20 * The contiguous blocks details which can be
21 * represented by a single extent
23 struct migrate_struct
{
24 ext4_lblk_t first_block
, last_block
, curr_block
;
25 ext4_fsblk_t first_pblock
, last_pblock
;
28 static int finish_range(handle_t
*handle
, struct inode
*inode
,
29 struct migrate_struct
*lb
)
32 int retval
= 0, needed
;
33 struct ext4_extent newext
;
34 struct ext4_ext_path
*path
;
35 if (lb
->first_pblock
== 0)
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);
46 retval
= PTR_ERR(path
);
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.
57 needed
= ext4_ext_calc_credits_for_single_extent(inode
,
58 lb
->last_block
- lb
->first_block
+ 1, path
);
61 * Make sure the credit we accumalated is not really high
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
));
71 retval
= ext4_journal_extend(handle
, needed
);
74 * IF not able to extend the journal restart the journal
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
));
83 retval
= ext4_ext_insert_extent(handle
, inode
, &path
, &newext
, 0);
85 up_write((&EXT4_I(inode
)->i_data_sem
));
86 ext4_ext_drop_refs(path
);
92 static int update_extent_range(handle_t
*handle
, struct inode
*inode
,
93 ext4_fsblk_t pblock
, struct migrate_struct
*lb
)
97 * See if we can add on to the existing range (if it exists)
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
;
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
;
117 static int update_ind_extent_range(handle_t
*handle
, struct inode
*inode
,
119 struct migrate_struct
*lb
)
121 struct buffer_head
*bh
;
124 unsigned long max_entries
= inode
->i_sb
->s_blocksize
>> 2;
126 bh
= ext4_sb_bread(inode
->i_sb
, pblock
, 0);
130 i_data
= (__le32
*)bh
->b_data
;
131 for (i
= 0; i
< max_entries
; i
++) {
133 retval
= update_extent_range(handle
, inode
,
134 le32_to_cpu(i_data
[i
]), lb
);
146 static int update_dind_extent_range(handle_t
*handle
, struct inode
*inode
,
148 struct migrate_struct
*lb
)
150 struct buffer_head
*bh
;
153 unsigned long max_entries
= inode
->i_sb
->s_blocksize
>> 2;
155 bh
= ext4_sb_bread(inode
->i_sb
, pblock
, 0);
159 i_data
= (__le32
*)bh
->b_data
;
160 for (i
= 0; i
< max_entries
; i
++) {
162 retval
= update_ind_extent_range(handle
, inode
,
163 le32_to_cpu(i_data
[i
]), lb
);
167 /* Only update the file block number */
168 lb
->curr_block
+= max_entries
;
176 static int update_tind_extent_range(handle_t
*handle
, struct inode
*inode
,
178 struct migrate_struct
*lb
)
180 struct buffer_head
*bh
;
183 unsigned long max_entries
= inode
->i_sb
->s_blocksize
>> 2;
185 bh
= ext4_sb_bread(inode
->i_sb
, pblock
, 0);
189 i_data
= (__le32
*)bh
->b_data
;
190 for (i
= 0; i
< max_entries
; i
++) {
192 retval
= update_dind_extent_range(handle
, inode
,
193 le32_to_cpu(i_data
[i
]), lb
);
197 /* Only update the file block number */
198 lb
->curr_block
+= max_entries
* max_entries
;
206 static int extend_credit_for_blkdel(handle_t
*handle
, struct inode
*inode
)
208 int retval
= 0, needed
;
210 if (ext4_handle_has_enough_credits(handle
, EXT4_RESERVE_TRANS_BLOCKS
+1))
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).
218 needed
= 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode
->i_sb
);
220 if (ext4_journal_extend(handle
, needed
) != 0)
221 retval
= ext4_journal_restart(handle
, needed
);
226 static int free_dind_blocks(handle_t
*handle
,
227 struct inode
*inode
, __le32 i_data
)
231 struct buffer_head
*bh
;
232 unsigned long max_entries
= inode
->i_sb
->s_blocksize
>> 2;
234 bh
= ext4_sb_bread(inode
->i_sb
, le32_to_cpu(i_data
), 0);
238 tmp_idata
= (__le32
*)bh
->b_data
;
239 for (i
= 0; i
< max_entries
; 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
);
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
);
256 static int free_tind_blocks(handle_t
*handle
,
257 struct inode
*inode
, __le32 i_data
)
261 struct buffer_head
*bh
;
262 unsigned long max_entries
= inode
->i_sb
->s_blocksize
>> 2;
264 bh
= ext4_sb_bread(inode
->i_sb
, le32_to_cpu(i_data
), 0);
268 tmp_idata
= (__le32
*)bh
->b_data
;
269 for (i
= 0; i
< max_entries
; i
++) {
271 retval
= free_dind_blocks(handle
,
272 inode
, tmp_idata
[i
]);
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
);
287 static int free_ind_block(handle_t
*handle
, struct inode
*inode
, __le32
*i_data
)
291 /* ei->i_data[EXT4_IND_BLOCK] */
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
);
300 /* ei->i_data[EXT4_DIND_BLOCK] */
302 retval
= free_dind_blocks(handle
, inode
, i_data
[1]);
307 /* ei->i_data[EXT4_TIND_BLOCK] */
309 retval
= free_tind_blocks(handle
, inode
, i_data
[2]);
316 static int ext4_ext_swap_inode_data(handle_t
*handle
, struct inode
*inode
,
317 struct inode
*tmp_inode
)
321 struct ext4_inode_info
*ei
= EXT4_I(inode
);
322 struct ext4_inode_info
*tmp_ei
= EXT4_I(tmp_inode
);
325 * One credit accounted for writing the
326 * i_data field of the original inode
328 retval
= ext4_journal_extend(handle
, 1);
330 retval
= ext4_journal_restart(handle
, 1);
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
];
339 down_write(&EXT4_I(inode
)->i_data_sem
);
341 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
342 * happened after we started the migrate. We need to
345 if (!ext4_test_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
)) {
347 up_write(&EXT4_I(inode
)->i_data_sem
);
350 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
352 * We have the extent map build with the tmp inode.
353 * Now copy the i_data across
355 ext4_set_inode_flag(inode
, EXT4_INODE_EXTENTS
);
356 memcpy(ei
->i_data
, tmp_ei
->i_data
, sizeof(ei
->i_data
));
359 * Update i_blocks with the new blocks that got
360 * allocated while adding extents for extent index
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.
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
);
373 * We mark the inode dirty after, because we decrement the
374 * i_blocks when freeing the indirect meta-data blocks
376 retval
= free_ind_block(handle
, inode
, i_data
);
377 ext4_mark_inode_dirty(handle
, inode
);
383 static int free_ext_idx(handle_t
*handle
, struct inode
*inode
,
384 struct ext4_extent_idx
*ix
)
388 struct buffer_head
*bh
;
389 struct ext4_extent_header
*eh
;
391 block
= ext4_idx_pblock(ix
);
392 bh
= ext4_sb_bread(inode
->i_sb
, block
, 0);
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
);
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
);
413 * Free the extent meta data blocks only
415 static int free_ext_block(handle_t
*handle
, struct inode
*inode
)
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)
423 * No extra blocks allocated for extent meta data
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
);
435 int ext4_ext_migrate(struct inode
*inode
)
437 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
441 struct ext4_inode_info
*ei
;
442 struct inode
*tmp_inode
= NULL
;
443 struct migrate_struct lb
;
444 unsigned long max_entries
;
449 * If the filesystem does not support extents, or the inode
450 * already is extent-based, error out.
452 if (!ext4_has_feature_extents(inode
->i_sb
) ||
453 (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
456 if (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
== 0)
458 * don't migrate fast symlink
462 percpu_down_write(&sbi
->s_writepages_rwsem
);
465 * Worst case we can touch the allocation bitmaps, a bgd
466 * block, and a block to link in the orphan list. We do need
467 * need to worry about credits for modifying the quota inode.
469 handle
= ext4_journal_start(inode
, EXT4_HT_MIGRATE
,
470 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode
->i_sb
));
472 if (IS_ERR(handle
)) {
473 retval
= PTR_ERR(handle
);
476 goal
= (((inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(inode
->i_sb
)) *
477 EXT4_INODES_PER_GROUP(inode
->i_sb
)) + 1;
478 owner
[0] = i_uid_read(inode
);
479 owner
[1] = i_gid_read(inode
);
480 tmp_inode
= ext4_new_inode(handle
, d_inode(inode
->i_sb
->s_root
),
481 S_IFREG
, NULL
, goal
, owner
, 0);
482 if (IS_ERR(tmp_inode
)) {
483 retval
= PTR_ERR(tmp_inode
);
484 ext4_journal_stop(handle
);
487 i_size_write(tmp_inode
, i_size_read(inode
));
489 * Set the i_nlink to zero so it will be deleted later
490 * when we drop inode reference.
492 clear_nlink(tmp_inode
);
494 ext4_ext_tree_init(handle
, tmp_inode
);
495 ext4_orphan_add(handle
, tmp_inode
);
496 ext4_journal_stop(handle
);
499 * start with one credit accounted for
500 * superblock modification.
502 * For the tmp_inode we already have committed the
503 * transaction that created the inode. Later as and
504 * when we add extents we extent the journal
507 * Even though we take i_mutex we can still cause block
508 * allocation via mmap write to holes. If we have allocated
509 * new blocks we fail migrate. New block allocation will
510 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
511 * with i_data_sem held to prevent racing with block
514 down_read(&EXT4_I(inode
)->i_data_sem
);
515 ext4_set_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
516 up_read((&EXT4_I(inode
)->i_data_sem
));
518 handle
= ext4_journal_start(inode
, EXT4_HT_MIGRATE
, 1);
519 if (IS_ERR(handle
)) {
521 * It is impossible to update on-disk structures without
522 * a handle, so just rollback in-core changes and live other
523 * work to orphan_list_cleanup()
525 ext4_orphan_del(NULL
, tmp_inode
);
526 retval
= PTR_ERR(handle
);
532 memset(&lb
, 0, sizeof(lb
));
534 /* 32 bit block address 4 bytes */
535 max_entries
= inode
->i_sb
->s_blocksize
>> 2;
536 for (i
= 0; i
< EXT4_NDIR_BLOCKS
; i
++) {
538 retval
= update_extent_range(handle
, tmp_inode
,
539 le32_to_cpu(i_data
[i
]), &lb
);
545 if (i_data
[EXT4_IND_BLOCK
]) {
546 retval
= update_ind_extent_range(handle
, tmp_inode
,
547 le32_to_cpu(i_data
[EXT4_IND_BLOCK
]), &lb
);
551 lb
.curr_block
+= max_entries
;
552 if (i_data
[EXT4_DIND_BLOCK
]) {
553 retval
= update_dind_extent_range(handle
, tmp_inode
,
554 le32_to_cpu(i_data
[EXT4_DIND_BLOCK
]), &lb
);
558 lb
.curr_block
+= max_entries
* max_entries
;
559 if (i_data
[EXT4_TIND_BLOCK
]) {
560 retval
= update_tind_extent_range(handle
, tmp_inode
,
561 le32_to_cpu(i_data
[EXT4_TIND_BLOCK
]), &lb
);
566 * Build the last extent
568 retval
= finish_range(handle
, tmp_inode
, &lb
);
572 * Failure case delete the extent information with the
575 free_ext_block(handle
, tmp_inode
);
577 retval
= ext4_ext_swap_inode_data(handle
, inode
, tmp_inode
);
580 * if we fail to swap inode data free the extent
581 * details of the tmp inode
583 free_ext_block(handle
, tmp_inode
);
586 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
587 if (ext4_journal_extend(handle
, 1) != 0)
588 ext4_journal_restart(handle
, 1);
591 * Mark the tmp_inode as of size zero
593 i_size_write(tmp_inode
, 0);
596 * set the i_blocks count to zero
597 * so that the ext4_evict_inode() does the
600 * We don't need to take the i_lock because
601 * the inode is not visible to user space.
603 tmp_inode
->i_blocks
= 0;
605 /* Reset the extent details */
606 ext4_ext_tree_init(handle
, tmp_inode
);
607 ext4_journal_stop(handle
);
609 unlock_new_inode(tmp_inode
);
612 percpu_up_write(&sbi
->s_writepages_rwsem
);
617 * Migrate a simple extent-based inode to use the i_blocks[] array
619 int ext4_ind_migrate(struct inode
*inode
)
621 struct ext4_extent_header
*eh
;
622 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
623 struct ext4_super_block
*es
= sbi
->s_es
;
624 struct ext4_inode_info
*ei
= EXT4_I(inode
);
625 struct ext4_extent
*ex
;
627 ext4_lblk_t start
, end
;
632 if (!ext4_has_feature_extents(inode
->i_sb
) ||
633 (!ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
636 if (ext4_has_feature_bigalloc(inode
->i_sb
))
640 * In order to get correct extent info, force all delayed allocation
641 * blocks to be allocated, otherwise delayed allocation blocks may not
642 * be reflected and bypass the checks on extent header.
644 if (test_opt(inode
->i_sb
, DELALLOC
))
645 ext4_alloc_da_blocks(inode
);
647 percpu_down_write(&sbi
->s_writepages_rwsem
);
649 handle
= ext4_journal_start(inode
, EXT4_HT_MIGRATE
, 1);
650 if (IS_ERR(handle
)) {
651 ret
= PTR_ERR(handle
);
655 down_write(&EXT4_I(inode
)->i_data_sem
);
656 ret
= ext4_ext_check_inode(inode
);
660 eh
= ext_inode_hdr(inode
);
661 ex
= EXT_FIRST_EXTENT(eh
);
662 if (ext4_blocks_count(es
) > EXT4_MAX_BLOCK_FILE_PHYS
||
663 eh
->eh_depth
!= 0 || le16_to_cpu(eh
->eh_entries
) > 1) {
667 if (eh
->eh_entries
== 0)
668 blk
= len
= start
= end
= 0;
670 len
= le16_to_cpu(ex
->ee_len
);
671 blk
= ext4_ext_pblock(ex
);
672 start
= le32_to_cpu(ex
->ee_block
);
673 end
= start
+ len
- 1;
674 if (end
>= EXT4_NDIR_BLOCKS
) {
680 ext4_clear_inode_flag(inode
, EXT4_INODE_EXTENTS
);
681 memset(ei
->i_data
, 0, sizeof(ei
->i_data
));
682 for (i
= start
; i
<= end
; i
++)
683 ei
->i_data
[i
] = cpu_to_le32(blk
++);
684 ext4_mark_inode_dirty(handle
, inode
);
686 ext4_journal_stop(handle
);
687 up_write(&EXT4_I(inode
)->i_data_sem
);
689 percpu_up_write(&sbi
->s_writepages_rwsem
);