1 // SPDX-License-Identifier: LGPL-2.1
3 * Copyright IBM Corporation, 2007
4 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
8 #include <linux/slab.h>
10 #include "ext4_extents.h"
13 * The contiguous blocks details which can be
14 * represented by a single extent
16 struct migrate_struct {
17 ext4_lblk_t first_block, last_block, curr_block;
18 ext4_fsblk_t first_pblock, last_pblock;
21 static int finish_range(handle_t *handle, struct inode *inode,
22 struct migrate_struct *lb)
25 int retval = 0, needed;
26 struct ext4_extent newext;
27 struct ext4_ext_path *path;
28 if (lb->first_pblock == 0)
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);
39 retval = PTR_ERR(path);
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.
50 needed = ext4_ext_calc_credits_for_single_extent(inode,
51 lb->last_block - lb->first_block + 1, path);
53 retval = ext4_datasem_ensure_credits(handle, inode, needed, needed, 0);
56 retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
58 up_write((&EXT4_I(inode)->i_data_sem));
59 ext4_ext_drop_refs(path);
65 static int update_extent_range(handle_t *handle, struct inode *inode,
66 ext4_fsblk_t pblock, struct migrate_struct *lb)
70 * See if we can add on to the existing range (if it exists)
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;
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;
90 static int update_ind_extent_range(handle_t *handle, struct inode *inode,
92 struct migrate_struct *lb)
94 struct buffer_head *bh;
97 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
99 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
103 i_data = (__le32 *)bh->b_data;
104 for (i = 0; i < max_entries; i++) {
106 retval = update_extent_range(handle, inode,
107 le32_to_cpu(i_data[i]), lb);
119 static int update_dind_extent_range(handle_t *handle, struct inode *inode,
121 struct migrate_struct *lb)
123 struct buffer_head *bh;
126 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
128 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
132 i_data = (__le32 *)bh->b_data;
133 for (i = 0; i < max_entries; i++) {
135 retval = update_ind_extent_range(handle, inode,
136 le32_to_cpu(i_data[i]), lb);
140 /* Only update the file block number */
141 lb->curr_block += max_entries;
149 static int update_tind_extent_range(handle_t *handle, struct inode *inode,
151 struct migrate_struct *lb)
153 struct buffer_head *bh;
156 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
158 bh = ext4_sb_bread(inode->i_sb, pblock, 0);
162 i_data = (__le32 *)bh->b_data;
163 for (i = 0; i < max_entries; i++) {
165 retval = update_dind_extent_range(handle, inode,
166 le32_to_cpu(i_data[i]), lb);
170 /* Only update the file block number */
171 lb->curr_block += max_entries * max_entries;
179 static int free_dind_blocks(handle_t *handle,
180 struct inode *inode, __le32 i_data)
184 struct buffer_head *bh;
185 struct super_block *sb = inode->i_sb;
186 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
189 bh = ext4_sb_bread(sb, le32_to_cpu(i_data), 0);
193 tmp_idata = (__le32 *)bh->b_data;
194 for (i = 0; i < max_entries; i++) {
196 err = ext4_journal_ensure_credits(handle,
197 EXT4_RESERVE_TRANS_BLOCKS,
198 ext4_free_metadata_revoke_credits(sb, 1));
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);
210 err = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
211 ext4_free_metadata_revoke_credits(sb, 1));
214 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
215 EXT4_FREE_BLOCKS_METADATA |
216 EXT4_FREE_BLOCKS_FORGET);
220 static int free_tind_blocks(handle_t *handle,
221 struct inode *inode, __le32 i_data)
225 struct buffer_head *bh;
226 unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
228 bh = ext4_sb_bread(inode->i_sb, le32_to_cpu(i_data), 0);
232 tmp_idata = (__le32 *)bh->b_data;
233 for (i = 0; i < max_entries; i++) {
235 retval = free_dind_blocks(handle,
236 inode, tmp_idata[i]);
244 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
245 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
248 ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
249 EXT4_FREE_BLOCKS_METADATA |
250 EXT4_FREE_BLOCKS_FORGET);
254 static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
258 /* ei->i_data[EXT4_IND_BLOCK] */
260 retval = ext4_journal_ensure_credits(handle,
261 EXT4_RESERVE_TRANS_BLOCKS,
262 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
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);
271 /* ei->i_data[EXT4_DIND_BLOCK] */
273 retval = free_dind_blocks(handle, inode, i_data[1]);
278 /* ei->i_data[EXT4_TIND_BLOCK] */
280 retval = free_tind_blocks(handle, inode, i_data[2]);
287 static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
288 struct inode *tmp_inode)
290 int retval, retval2 = 0;
292 struct ext4_inode_info *ei = EXT4_I(inode);
293 struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
296 * One credit accounted for writing the
297 * i_data field of the original inode
299 retval = ext4_journal_ensure_credits(handle, 1, 0);
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];
307 down_write(&EXT4_I(inode)->i_data_sem);
309 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
310 * happened after we started the migrate. We need to
313 if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
315 up_write(&EXT4_I(inode)->i_data_sem);
318 ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
320 * We have the extent map build with the tmp inode.
321 * Now copy the i_data across
323 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
324 memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
327 * Update i_blocks with the new blocks that got
328 * allocated while adding extents for extent index
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.
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);
341 * We mark the inode dirty after, because we decrement the
342 * i_blocks when freeing the indirect meta-data blocks
344 retval = free_ind_block(handle, inode, i_data);
345 retval2 = ext4_mark_inode_dirty(handle, inode);
346 if (unlikely(retval2 && !retval))
353 static int free_ext_idx(handle_t *handle, struct inode *inode,
354 struct ext4_extent_idx *ix)
358 struct buffer_head *bh;
359 struct ext4_extent_header *eh;
361 block = ext4_idx_pblock(ix);
362 bh = ext4_sb_bread(inode->i_sb, block, 0);
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);
378 retval = ext4_journal_ensure_credits(handle, EXT4_RESERVE_TRANS_BLOCKS,
379 ext4_free_metadata_revoke_credits(inode->i_sb, 1));
382 ext4_free_blocks(handle, inode, NULL, block, 1,
383 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
388 * Free the extent meta data blocks only
390 static int free_ext_block(handle_t *handle, struct inode *inode)
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)
398 * No extra blocks allocated for extent meta data
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);
410 int ext4_ext_migrate(struct inode *inode)
412 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
416 struct ext4_inode_info *ei;
417 struct inode *tmp_inode = NULL;
418 struct migrate_struct lb;
419 unsigned long max_entries;
424 * If the filesystem does not support extents, or the inode
425 * already is extent-based, error out.
427 if (!ext4_has_feature_extents(inode->i_sb) ||
428 (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
431 if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
433 * don't migrate fast symlink
437 percpu_down_write(&sbi->s_writepages_rwsem);
440 * Worst case we can touch the allocation bitmaps, a bgd
441 * block, and a block to link in the orphan list. We do need
442 * need to worry about credits for modifying the quota inode.
444 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
445 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
447 if (IS_ERR(handle)) {
448 retval = PTR_ERR(handle);
451 goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
452 EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
453 owner[0] = i_uid_read(inode);
454 owner[1] = i_gid_read(inode);
455 tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
456 S_IFREG, NULL, goal, owner, 0);
457 if (IS_ERR(tmp_inode)) {
458 retval = PTR_ERR(tmp_inode);
459 ext4_journal_stop(handle);
462 i_size_write(tmp_inode, i_size_read(inode));
464 * Set the i_nlink to zero so it will be deleted later
465 * when we drop inode reference.
467 clear_nlink(tmp_inode);
469 ext4_ext_tree_init(handle, tmp_inode);
470 ext4_orphan_add(handle, tmp_inode);
471 ext4_journal_stop(handle);
474 * start with one credit accounted for
475 * superblock modification.
477 * For the tmp_inode we already have committed the
478 * transaction that created the inode. Later as and
479 * when we add extents we extent the journal
482 * Even though we take i_mutex we can still cause block
483 * allocation via mmap write to holes. If we have allocated
484 * new blocks we fail migrate. New block allocation will
485 * clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
486 * with i_data_sem held to prevent racing with block
489 down_read(&EXT4_I(inode)->i_data_sem);
490 ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
491 up_read((&EXT4_I(inode)->i_data_sem));
493 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
494 if (IS_ERR(handle)) {
496 * It is impossible to update on-disk structures without
497 * a handle, so just rollback in-core changes and live other
498 * work to orphan_list_cleanup()
500 ext4_orphan_del(NULL, tmp_inode);
501 retval = PTR_ERR(handle);
507 memset(&lb, 0, sizeof(lb));
509 /* 32 bit block address 4 bytes */
510 max_entries = inode->i_sb->s_blocksize >> 2;
511 for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
513 retval = update_extent_range(handle, tmp_inode,
514 le32_to_cpu(i_data[i]), &lb);
520 if (i_data[EXT4_IND_BLOCK]) {
521 retval = update_ind_extent_range(handle, tmp_inode,
522 le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
526 lb.curr_block += max_entries;
527 if (i_data[EXT4_DIND_BLOCK]) {
528 retval = update_dind_extent_range(handle, tmp_inode,
529 le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
533 lb.curr_block += max_entries * max_entries;
534 if (i_data[EXT4_TIND_BLOCK]) {
535 retval = update_tind_extent_range(handle, tmp_inode,
536 le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
541 * Build the last extent
543 retval = finish_range(handle, tmp_inode, &lb);
547 * Failure case delete the extent information with the
550 free_ext_block(handle, tmp_inode);
552 retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
555 * if we fail to swap inode data free the extent
556 * details of the tmp inode
558 free_ext_block(handle, tmp_inode);
561 /* We mark the tmp_inode dirty via ext4_ext_tree_init. */
562 retval = ext4_journal_ensure_credits(handle, 1, 0);
566 * Mark the tmp_inode as of size zero
568 i_size_write(tmp_inode, 0);
571 * set the i_blocks count to zero
572 * so that the ext4_evict_inode() does the
575 * We don't need to take the i_lock because
576 * the inode is not visible to user space.
578 tmp_inode->i_blocks = 0;
580 /* Reset the extent details */
581 ext4_ext_tree_init(handle, tmp_inode);
583 ext4_journal_stop(handle);
585 unlock_new_inode(tmp_inode);
588 percpu_up_write(&sbi->s_writepages_rwsem);
593 * Migrate a simple extent-based inode to use the i_blocks[] array
595 int ext4_ind_migrate(struct inode *inode)
597 struct ext4_extent_header *eh;
598 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
599 struct ext4_super_block *es = sbi->s_es;
600 struct ext4_inode_info *ei = EXT4_I(inode);
601 struct ext4_extent *ex;
603 ext4_lblk_t start, end;
608 if (!ext4_has_feature_extents(inode->i_sb) ||
609 (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
612 if (ext4_has_feature_bigalloc(inode->i_sb))
616 * In order to get correct extent info, force all delayed allocation
617 * blocks to be allocated, otherwise delayed allocation blocks may not
618 * be reflected and bypass the checks on extent header.
620 if (test_opt(inode->i_sb, DELALLOC))
621 ext4_alloc_da_blocks(inode);
623 percpu_down_write(&sbi->s_writepages_rwsem);
625 handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
626 if (IS_ERR(handle)) {
627 ret = PTR_ERR(handle);
631 down_write(&EXT4_I(inode)->i_data_sem);
632 ret = ext4_ext_check_inode(inode);
636 eh = ext_inode_hdr(inode);
637 ex = EXT_FIRST_EXTENT(eh);
638 if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
639 eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
643 if (eh->eh_entries == 0)
644 blk = len = start = end = 0;
646 len = le16_to_cpu(ex->ee_len);
647 blk = ext4_ext_pblock(ex);
648 start = le32_to_cpu(ex->ee_block);
649 end = start + len - 1;
650 if (end >= EXT4_NDIR_BLOCKS) {
656 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
657 memset(ei->i_data, 0, sizeof(ei->i_data));
658 for (i = start; i <= end; i++)
659 ei->i_data[i] = cpu_to_le32(blk++);
660 ret2 = ext4_mark_inode_dirty(handle, inode);
661 if (unlikely(ret2 && !ret))
664 ext4_journal_stop(handle);
665 up_write(&EXT4_I(inode)->i_data_sem);
667 percpu_up_write(&sbi->s_writepages_rwsem);