2 * linux/fs/ext4/inode.c
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
11 * linux/fs/minix/inode.c
13 * Copyright (C) 1991, 1992 Linus Torvalds
15 * 64-bit file support on 64-bit platforms by Jakub Jelinek
16 * (jj@sunsite.ms.mff.cuni.cz)
18 * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
22 #include <linux/time.h>
23 #include <linux/jbd2.h>
24 #include <linux/highuid.h>
25 #include <linux/pagemap.h>
26 #include <linux/quotaops.h>
27 #include <linux/string.h>
28 #include <linux/buffer_head.h>
29 #include <linux/writeback.h>
30 #include <linux/pagevec.h>
31 #include <linux/mpage.h>
32 #include <linux/namei.h>
33 #include <linux/uio.h>
34 #include <linux/bio.h>
35 #include <linux/workqueue.h>
36 #include <linux/kernel.h>
37 #include <linux/printk.h>
38 #include <linux/slab.h>
39 #include <linux/ratelimit.h>
40 #include <linux/aio.h>
41 #include <linux/bitops.h>
43 #include "ext4_jbd2.h"
48 #include <trace/events/ext4.h>
50 #define MPAGE_DA_EXTENT_TAIL 0x01
52 static __u32
ext4_inode_csum(struct inode
*inode
, struct ext4_inode
*raw
,
53 struct ext4_inode_info
*ei
)
55 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
60 csum_lo
= le16_to_cpu(raw
->i_checksum_lo
);
61 raw
->i_checksum_lo
= 0;
62 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
63 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
)) {
64 csum_hi
= le16_to_cpu(raw
->i_checksum_hi
);
65 raw
->i_checksum_hi
= 0;
68 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)raw
,
69 EXT4_INODE_SIZE(inode
->i_sb
));
71 raw
->i_checksum_lo
= cpu_to_le16(csum_lo
);
72 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
73 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
74 raw
->i_checksum_hi
= cpu_to_le16(csum_hi
);
79 static int ext4_inode_csum_verify(struct inode
*inode
, struct ext4_inode
*raw
,
80 struct ext4_inode_info
*ei
)
82 __u32 provided
, calculated
;
84 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
85 cpu_to_le32(EXT4_OS_LINUX
) ||
86 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
87 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
90 provided
= le16_to_cpu(raw
->i_checksum_lo
);
91 calculated
= ext4_inode_csum(inode
, raw
, ei
);
92 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
93 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
94 provided
|= ((__u32
)le16_to_cpu(raw
->i_checksum_hi
)) << 16;
98 return provided
== calculated
;
101 static void ext4_inode_csum_set(struct inode
*inode
, struct ext4_inode
*raw
,
102 struct ext4_inode_info
*ei
)
106 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
107 cpu_to_le32(EXT4_OS_LINUX
) ||
108 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
109 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
112 csum
= ext4_inode_csum(inode
, raw
, ei
);
113 raw
->i_checksum_lo
= cpu_to_le16(csum
& 0xFFFF);
114 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
115 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
116 raw
->i_checksum_hi
= cpu_to_le16(csum
>> 16);
119 static inline int ext4_begin_ordered_truncate(struct inode
*inode
,
122 trace_ext4_begin_ordered_truncate(inode
, new_size
);
124 * If jinode is zero, then we never opened the file for
125 * writing, so there's no need to call
126 * jbd2_journal_begin_ordered_truncate() since there's no
127 * outstanding writes we need to flush.
129 if (!EXT4_I(inode
)->jinode
)
131 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode
),
132 EXT4_I(inode
)->jinode
,
136 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
137 unsigned int length
);
138 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
139 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
140 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
144 * Test whether an inode is a fast symlink.
146 static int ext4_inode_is_fast_symlink(struct inode
*inode
)
148 int ea_blocks
= EXT4_I(inode
)->i_file_acl
?
149 EXT4_CLUSTER_SIZE(inode
->i_sb
) >> 9 : 0;
151 if (ext4_has_inline_data(inode
))
154 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
158 * Restart the transaction associated with *handle. This does a commit,
159 * so before we call here everything must be consistently dirtied against
162 int ext4_truncate_restart_trans(handle_t
*handle
, struct inode
*inode
,
168 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
169 * moment, get_block can be called only for blocks inside i_size since
170 * page cache has been already dropped and writes are blocked by
171 * i_mutex. So we can safely drop the i_data_sem here.
173 BUG_ON(EXT4_JOURNAL(inode
) == NULL
);
174 jbd_debug(2, "restarting handle %p\n", handle
);
175 up_write(&EXT4_I(inode
)->i_data_sem
);
176 ret
= ext4_journal_restart(handle
, nblocks
);
177 down_write(&EXT4_I(inode
)->i_data_sem
);
178 ext4_discard_preallocations(inode
);
184 * Called at the last iput() if i_nlink is zero.
186 void ext4_evict_inode(struct inode
*inode
)
191 trace_ext4_evict_inode(inode
);
193 if (inode
->i_nlink
) {
195 * When journalling data dirty buffers are tracked only in the
196 * journal. So although mm thinks everything is clean and
197 * ready for reaping the inode might still have some pages to
198 * write in the running transaction or waiting to be
199 * checkpointed. Thus calling jbd2_journal_invalidatepage()
200 * (via truncate_inode_pages()) to discard these buffers can
201 * cause data loss. Also even if we did not discard these
202 * buffers, we would have no way to find them after the inode
203 * is reaped and thus user could see stale data if he tries to
204 * read them before the transaction is checkpointed. So be
205 * careful and force everything to disk here... We use
206 * ei->i_datasync_tid to store the newest transaction
207 * containing inode's data.
209 * Note that directories do not have this problem because they
210 * don't use page cache.
212 if (ext4_should_journal_data(inode
) &&
213 (S_ISLNK(inode
->i_mode
) || S_ISREG(inode
->i_mode
)) &&
214 inode
->i_ino
!= EXT4_JOURNAL_INO
) {
215 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
216 tid_t commit_tid
= EXT4_I(inode
)->i_datasync_tid
;
218 jbd2_complete_transaction(journal
, commit_tid
);
219 filemap_write_and_wait(&inode
->i_data
);
221 truncate_inode_pages_final(&inode
->i_data
);
223 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
227 if (!is_bad_inode(inode
))
228 dquot_initialize(inode
);
230 if (ext4_should_order_data(inode
))
231 ext4_begin_ordered_truncate(inode
, 0);
232 truncate_inode_pages_final(&inode
->i_data
);
234 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
235 if (is_bad_inode(inode
))
239 * Protect us against freezing - iput() caller didn't have to have any
240 * protection against it
242 sb_start_intwrite(inode
->i_sb
);
243 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
,
244 ext4_blocks_for_truncate(inode
)+3);
245 if (IS_ERR(handle
)) {
246 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
248 * If we're going to skip the normal cleanup, we still need to
249 * make sure that the in-core orphan linked list is properly
252 ext4_orphan_del(NULL
, inode
);
253 sb_end_intwrite(inode
->i_sb
);
258 ext4_handle_sync(handle
);
260 err
= ext4_mark_inode_dirty(handle
, inode
);
262 ext4_warning(inode
->i_sb
,
263 "couldn't mark inode dirty (err %d)", err
);
267 ext4_truncate(inode
);
270 * ext4_ext_truncate() doesn't reserve any slop when it
271 * restarts journal transactions; therefore there may not be
272 * enough credits left in the handle to remove the inode from
273 * the orphan list and set the dtime field.
275 if (!ext4_handle_has_enough_credits(handle
, 3)) {
276 err
= ext4_journal_extend(handle
, 3);
278 err
= ext4_journal_restart(handle
, 3);
280 ext4_warning(inode
->i_sb
,
281 "couldn't extend journal (err %d)", err
);
283 ext4_journal_stop(handle
);
284 ext4_orphan_del(NULL
, inode
);
285 sb_end_intwrite(inode
->i_sb
);
291 * Kill off the orphan record which ext4_truncate created.
292 * AKPM: I think this can be inside the above `if'.
293 * Note that ext4_orphan_del() has to be able to cope with the
294 * deletion of a non-existent orphan - this is because we don't
295 * know if ext4_truncate() actually created an orphan record.
296 * (Well, we could do this if we need to, but heck - it works)
298 ext4_orphan_del(handle
, inode
);
299 EXT4_I(inode
)->i_dtime
= get_seconds();
302 * One subtle ordering requirement: if anything has gone wrong
303 * (transaction abort, IO errors, whatever), then we can still
304 * do these next steps (the fs will already have been marked as
305 * having errors), but we can't free the inode if the mark_dirty
308 if (ext4_mark_inode_dirty(handle
, inode
))
309 /* If that failed, just do the required in-core inode clear. */
310 ext4_clear_inode(inode
);
312 ext4_free_inode(handle
, inode
);
313 ext4_journal_stop(handle
);
314 sb_end_intwrite(inode
->i_sb
);
317 ext4_clear_inode(inode
); /* We must guarantee clearing of inode... */
321 qsize_t
*ext4_get_reserved_space(struct inode
*inode
)
323 return &EXT4_I(inode
)->i_reserved_quota
;
328 * Calculate the number of metadata blocks need to reserve
329 * to allocate a block located at @lblock
331 static int ext4_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
333 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
334 return ext4_ext_calc_metadata_amount(inode
, lblock
);
336 return ext4_ind_calc_metadata_amount(inode
, lblock
);
340 * Called with i_data_sem down, which is important since we can call
341 * ext4_discard_preallocations() from here.
343 void ext4_da_update_reserve_space(struct inode
*inode
,
344 int used
, int quota_claim
)
346 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
347 struct ext4_inode_info
*ei
= EXT4_I(inode
);
349 spin_lock(&ei
->i_block_reservation_lock
);
350 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
351 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
352 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
353 "with only %d reserved data blocks",
354 __func__
, inode
->i_ino
, used
,
355 ei
->i_reserved_data_blocks
);
357 used
= ei
->i_reserved_data_blocks
;
360 if (unlikely(ei
->i_allocated_meta_blocks
> ei
->i_reserved_meta_blocks
)) {
361 ext4_warning(inode
->i_sb
, "ino %lu, allocated %d "
362 "with only %d reserved metadata blocks "
363 "(releasing %d blocks with reserved %d data blocks)",
364 inode
->i_ino
, ei
->i_allocated_meta_blocks
,
365 ei
->i_reserved_meta_blocks
, used
,
366 ei
->i_reserved_data_blocks
);
368 ei
->i_allocated_meta_blocks
= ei
->i_reserved_meta_blocks
;
371 /* Update per-inode reservations */
372 ei
->i_reserved_data_blocks
-= used
;
373 ei
->i_reserved_meta_blocks
-= ei
->i_allocated_meta_blocks
;
374 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
375 used
+ ei
->i_allocated_meta_blocks
);
376 ei
->i_allocated_meta_blocks
= 0;
378 if (ei
->i_reserved_data_blocks
== 0) {
380 * We can release all of the reserved metadata blocks
381 * only when we have written all of the delayed
384 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
385 ei
->i_reserved_meta_blocks
);
386 ei
->i_reserved_meta_blocks
= 0;
387 ei
->i_da_metadata_calc_len
= 0;
389 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
391 /* Update quota subsystem for data blocks */
393 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
396 * We did fallocate with an offset that is already delayed
397 * allocated. So on delayed allocated writeback we should
398 * not re-claim the quota for fallocated blocks.
400 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
404 * If we have done all the pending block allocations and if
405 * there aren't any writers on the inode, we can discard the
406 * inode's preallocations.
408 if ((ei
->i_reserved_data_blocks
== 0) &&
409 (atomic_read(&inode
->i_writecount
) == 0))
410 ext4_discard_preallocations(inode
);
413 static int __check_block_validity(struct inode
*inode
, const char *func
,
415 struct ext4_map_blocks
*map
)
417 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
419 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
420 "lblock %lu mapped to illegal pblock "
421 "(length %d)", (unsigned long) map
->m_lblk
,
428 #define check_block_validity(inode, map) \
429 __check_block_validity((inode), __func__, __LINE__, (map))
431 #ifdef ES_AGGRESSIVE_TEST
432 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
434 struct ext4_map_blocks
*es_map
,
435 struct ext4_map_blocks
*map
,
442 * There is a race window that the result is not the same.
443 * e.g. xfstests #223 when dioread_nolock enables. The reason
444 * is that we lookup a block mapping in extent status tree with
445 * out taking i_data_sem. So at the time the unwritten extent
446 * could be converted.
448 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
449 down_read(&EXT4_I(inode
)->i_data_sem
);
450 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
451 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
452 EXT4_GET_BLOCKS_KEEP_SIZE
);
454 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
455 EXT4_GET_BLOCKS_KEEP_SIZE
);
457 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
458 up_read((&EXT4_I(inode
)->i_data_sem
));
460 * Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
461 * because it shouldn't be marked in es_map->m_flags.
463 map
->m_flags
&= ~(EXT4_MAP_FROM_CLUSTER
| EXT4_MAP_BOUNDARY
);
466 * We don't check m_len because extent will be collpased in status
467 * tree. So the m_len might not equal.
469 if (es_map
->m_lblk
!= map
->m_lblk
||
470 es_map
->m_flags
!= map
->m_flags
||
471 es_map
->m_pblk
!= map
->m_pblk
) {
472 printk("ES cache assertion failed for inode: %lu "
473 "es_cached ex [%d/%d/%llu/%x] != "
474 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
475 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
476 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
477 map
->m_len
, map
->m_pblk
, map
->m_flags
,
481 #endif /* ES_AGGRESSIVE_TEST */
484 * The ext4_map_blocks() function tries to look up the requested blocks,
485 * and returns if the blocks are already mapped.
487 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
488 * and store the allocated blocks in the result buffer head and mark it
491 * If file type is extents based, it will call ext4_ext_map_blocks(),
492 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
495 * On success, it returns the number of blocks being mapped or allocated.
496 * if create==0 and the blocks are pre-allocated and unwritten block,
497 * the result buffer head is unmapped. If the create ==1, it will make sure
498 * the buffer head is mapped.
500 * It returns 0 if plain look up failed (blocks have not been allocated), in
501 * that case, buffer head is unmapped
503 * It returns the error in case of allocation failure.
505 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
506 struct ext4_map_blocks
*map
, int flags
)
508 struct extent_status es
;
511 #ifdef ES_AGGRESSIVE_TEST
512 struct ext4_map_blocks orig_map
;
514 memcpy(&orig_map
, map
, sizeof(*map
));
518 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
519 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
520 (unsigned long) map
->m_lblk
);
523 * ext4_map_blocks returns an int, and m_len is an unsigned int
525 if (unlikely(map
->m_len
> INT_MAX
))
526 map
->m_len
= INT_MAX
;
528 /* We can handle the block number less than EXT_MAX_BLOCKS */
529 if (unlikely(map
->m_lblk
>= EXT_MAX_BLOCKS
))
532 /* Lookup extent status tree firstly */
533 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
534 ext4_es_lru_add(inode
);
535 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
536 map
->m_pblk
= ext4_es_pblock(&es
) +
537 map
->m_lblk
- es
.es_lblk
;
538 map
->m_flags
|= ext4_es_is_written(&es
) ?
539 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
540 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
541 if (retval
> map
->m_len
)
544 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
549 #ifdef ES_AGGRESSIVE_TEST
550 ext4_map_blocks_es_recheck(handle
, inode
, map
,
557 * Try to see if we can get the block without requesting a new
560 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
561 down_read(&EXT4_I(inode
)->i_data_sem
);
562 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
563 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
564 EXT4_GET_BLOCKS_KEEP_SIZE
);
566 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
567 EXT4_GET_BLOCKS_KEEP_SIZE
);
572 if (unlikely(retval
!= map
->m_len
)) {
573 ext4_warning(inode
->i_sb
,
574 "ES len assertion failed for inode "
575 "%lu: retval %d != map->m_len %d",
576 inode
->i_ino
, retval
, map
->m_len
);
580 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
581 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
582 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
583 ext4_find_delalloc_range(inode
, map
->m_lblk
,
584 map
->m_lblk
+ map
->m_len
- 1))
585 status
|= EXTENT_STATUS_DELAYED
;
586 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
587 map
->m_len
, map
->m_pblk
, status
);
591 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
592 up_read((&EXT4_I(inode
)->i_data_sem
));
595 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
596 ret
= check_block_validity(inode
, map
);
601 /* If it is only a block(s) look up */
602 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
606 * Returns if the blocks have already allocated
608 * Note that if blocks have been preallocated
609 * ext4_ext_get_block() returns the create = 0
610 * with buffer head unmapped.
612 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
614 * If we need to convert extent to unwritten
615 * we continue and do the actual work in
616 * ext4_ext_map_blocks()
618 if (!(flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
))
622 * Here we clear m_flags because after allocating an new extent,
623 * it will be set again.
625 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
628 * New blocks allocate and/or writing to unwritten extent
629 * will possibly result in updating i_data, so we take
630 * the write lock of i_data_sem, and call get_blocks()
631 * with create == 1 flag.
633 down_write(&EXT4_I(inode
)->i_data_sem
);
636 * if the caller is from delayed allocation writeout path
637 * we have already reserved fs blocks for allocation
638 * let the underlying get_block() function know to
639 * avoid double accounting
641 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
642 ext4_set_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
644 * We need to check for EXT4 here because migrate
645 * could have changed the inode type in between
647 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
648 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
650 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
652 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
654 * We allocated new blocks which will result in
655 * i_data's format changing. Force the migrate
656 * to fail by clearing migrate flags
658 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
662 * Update reserved blocks/metadata blocks after successful
663 * block allocation which had been deferred till now. We don't
664 * support fallocate for non extent files. So we can update
665 * reserve space here.
668 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
669 ext4_da_update_reserve_space(inode
, retval
, 1);
671 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
672 ext4_clear_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
677 if (unlikely(retval
!= map
->m_len
)) {
678 ext4_warning(inode
->i_sb
,
679 "ES len assertion failed for inode "
680 "%lu: retval %d != map->m_len %d",
681 inode
->i_ino
, retval
, map
->m_len
);
686 * If the extent has been zeroed out, we don't need to update
687 * extent status tree.
689 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
690 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
691 if (ext4_es_is_written(&es
))
694 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
695 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
696 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
697 ext4_find_delalloc_range(inode
, map
->m_lblk
,
698 map
->m_lblk
+ map
->m_len
- 1))
699 status
|= EXTENT_STATUS_DELAYED
;
700 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
701 map
->m_pblk
, status
);
707 up_write((&EXT4_I(inode
)->i_data_sem
));
708 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
709 ret
= check_block_validity(inode
, map
);
716 /* Maximum number of blocks we map for direct IO at once. */
717 #define DIO_MAX_BLOCKS 4096
719 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
720 struct buffer_head
*bh
, int flags
)
722 handle_t
*handle
= ext4_journal_current_handle();
723 struct ext4_map_blocks map
;
724 int ret
= 0, started
= 0;
727 if (ext4_has_inline_data(inode
))
731 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
733 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
734 /* Direct IO write... */
735 if (map
.m_len
> DIO_MAX_BLOCKS
)
736 map
.m_len
= DIO_MAX_BLOCKS
;
737 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
738 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
740 if (IS_ERR(handle
)) {
741 ret
= PTR_ERR(handle
);
747 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
749 ext4_io_end_t
*io_end
= ext4_inode_aio(inode
);
751 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
752 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
753 if (io_end
&& io_end
->flag
& EXT4_IO_END_UNWRITTEN
)
754 set_buffer_defer_completion(bh
);
755 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
759 ext4_journal_stop(handle
);
763 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
764 struct buffer_head
*bh
, int create
)
766 return _ext4_get_block(inode
, iblock
, bh
,
767 create
? EXT4_GET_BLOCKS_CREATE
: 0);
771 * `handle' can be NULL if create is zero
773 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
774 ext4_lblk_t block
, int create
, int *errp
)
776 struct ext4_map_blocks map
;
777 struct buffer_head
*bh
;
780 J_ASSERT(handle
!= NULL
|| create
== 0);
784 err
= ext4_map_blocks(handle
, inode
, &map
,
785 create
? EXT4_GET_BLOCKS_CREATE
: 0);
787 /* ensure we send some value back into *errp */
790 if (create
&& err
== 0)
791 err
= -ENOSPC
; /* should never happen */
797 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
802 if (map
.m_flags
& EXT4_MAP_NEW
) {
803 J_ASSERT(create
!= 0);
804 J_ASSERT(handle
!= NULL
);
807 * Now that we do not always journal data, we should
808 * keep in mind whether this should always journal the
809 * new buffer as metadata. For now, regular file
810 * writes use ext4_get_block instead, so it's not a
814 BUFFER_TRACE(bh
, "call get_create_access");
815 fatal
= ext4_journal_get_create_access(handle
, bh
);
816 if (!fatal
&& !buffer_uptodate(bh
)) {
817 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
818 set_buffer_uptodate(bh
);
821 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
822 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
826 BUFFER_TRACE(bh
, "not a new buffer");
836 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
837 ext4_lblk_t block
, int create
, int *err
)
839 struct buffer_head
*bh
;
841 bh
= ext4_getblk(handle
, inode
, block
, create
, err
);
844 if (buffer_uptodate(bh
))
846 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
848 if (buffer_uptodate(bh
))
855 int ext4_walk_page_buffers(handle_t
*handle
,
856 struct buffer_head
*head
,
860 int (*fn
)(handle_t
*handle
,
861 struct buffer_head
*bh
))
863 struct buffer_head
*bh
;
864 unsigned block_start
, block_end
;
865 unsigned blocksize
= head
->b_size
;
867 struct buffer_head
*next
;
869 for (bh
= head
, block_start
= 0;
870 ret
== 0 && (bh
!= head
|| !block_start
);
871 block_start
= block_end
, bh
= next
) {
872 next
= bh
->b_this_page
;
873 block_end
= block_start
+ blocksize
;
874 if (block_end
<= from
|| block_start
>= to
) {
875 if (partial
&& !buffer_uptodate(bh
))
879 err
= (*fn
)(handle
, bh
);
887 * To preserve ordering, it is essential that the hole instantiation and
888 * the data write be encapsulated in a single transaction. We cannot
889 * close off a transaction and start a new one between the ext4_get_block()
890 * and the commit_write(). So doing the jbd2_journal_start at the start of
891 * prepare_write() is the right place.
893 * Also, this function can nest inside ext4_writepage(). In that case, we
894 * *know* that ext4_writepage() has generated enough buffer credits to do the
895 * whole page. So we won't block on the journal in that case, which is good,
896 * because the caller may be PF_MEMALLOC.
898 * By accident, ext4 can be reentered when a transaction is open via
899 * quota file writes. If we were to commit the transaction while thus
900 * reentered, there can be a deadlock - we would be holding a quota
901 * lock, and the commit would never complete if another thread had a
902 * transaction open and was blocking on the quota lock - a ranking
905 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
906 * will _not_ run commit under these circumstances because handle->h_ref
907 * is elevated. We'll still have enough credits for the tiny quotafile
910 int do_journal_get_write_access(handle_t
*handle
,
911 struct buffer_head
*bh
)
913 int dirty
= buffer_dirty(bh
);
916 if (!buffer_mapped(bh
) || buffer_freed(bh
))
919 * __block_write_begin() could have dirtied some buffers. Clean
920 * the dirty bit as jbd2_journal_get_write_access() could complain
921 * otherwise about fs integrity issues. Setting of the dirty bit
922 * by __block_write_begin() isn't a real problem here as we clear
923 * the bit before releasing a page lock and thus writeback cannot
924 * ever write the buffer.
927 clear_buffer_dirty(bh
);
928 BUFFER_TRACE(bh
, "get write access");
929 ret
= ext4_journal_get_write_access(handle
, bh
);
931 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
935 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
936 struct buffer_head
*bh_result
, int create
);
937 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
938 loff_t pos
, unsigned len
, unsigned flags
,
939 struct page
**pagep
, void **fsdata
)
941 struct inode
*inode
= mapping
->host
;
942 int ret
, needed_blocks
;
949 trace_ext4_write_begin(inode
, pos
, len
, flags
);
951 * Reserve one block more for addition to orphan list in case
952 * we allocate blocks but write fails for some reason
954 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
955 index
= pos
>> PAGE_CACHE_SHIFT
;
956 from
= pos
& (PAGE_CACHE_SIZE
- 1);
959 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
960 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
969 * grab_cache_page_write_begin() can take a long time if the
970 * system is thrashing due to memory pressure, or if the page
971 * is being written back. So grab it first before we start
972 * the transaction handle. This also allows us to allocate
973 * the page (if needed) without using GFP_NOFS.
976 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
982 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
983 if (IS_ERR(handle
)) {
984 page_cache_release(page
);
985 return PTR_ERR(handle
);
989 if (page
->mapping
!= mapping
) {
990 /* The page got truncated from under us */
992 page_cache_release(page
);
993 ext4_journal_stop(handle
);
996 /* In case writeback began while the page was unlocked */
997 wait_for_stable_page(page
);
999 if (ext4_should_dioread_nolock(inode
))
1000 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
1002 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
1004 if (!ret
&& ext4_should_journal_data(inode
)) {
1005 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
1007 do_journal_get_write_access
);
1013 * __block_write_begin may have instantiated a few blocks
1014 * outside i_size. Trim these off again. Don't need
1015 * i_size_read because we hold i_mutex.
1017 * Add inode to orphan list in case we crash before
1020 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1021 ext4_orphan_add(handle
, inode
);
1023 ext4_journal_stop(handle
);
1024 if (pos
+ len
> inode
->i_size
) {
1025 ext4_truncate_failed_write(inode
);
1027 * If truncate failed early the inode might
1028 * still be on the orphan list; we need to
1029 * make sure the inode is removed from the
1030 * orphan list in that case.
1033 ext4_orphan_del(NULL
, inode
);
1036 if (ret
== -ENOSPC
&&
1037 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
1039 page_cache_release(page
);
1046 /* For write_end() in data=journal mode */
1047 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1050 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1052 set_buffer_uptodate(bh
);
1053 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1054 clear_buffer_meta(bh
);
1055 clear_buffer_prio(bh
);
1060 * We need to pick up the new inode size which generic_commit_write gave us
1061 * `file' can be NULL - eg, when called from page_symlink().
1063 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1064 * buffers are managed internally.
1066 static int ext4_write_end(struct file
*file
,
1067 struct address_space
*mapping
,
1068 loff_t pos
, unsigned len
, unsigned copied
,
1069 struct page
*page
, void *fsdata
)
1071 handle_t
*handle
= ext4_journal_current_handle();
1072 struct inode
*inode
= mapping
->host
;
1074 int i_size_changed
= 0;
1076 trace_ext4_write_end(inode
, pos
, len
, copied
);
1077 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1078 ret
= ext4_jbd2_file_inode(handle
, inode
);
1081 page_cache_release(page
);
1086 if (ext4_has_inline_data(inode
)) {
1087 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1093 copied
= block_write_end(file
, mapping
, pos
,
1094 len
, copied
, page
, fsdata
);
1097 * No need to use i_size_read() here, the i_size
1098 * cannot change under us because we hole i_mutex.
1100 * But it's important to update i_size while still holding page lock:
1101 * page writeout could otherwise come in and zero beyond i_size.
1103 if (pos
+ copied
> inode
->i_size
) {
1104 i_size_write(inode
, pos
+ copied
);
1108 if (pos
+ copied
> EXT4_I(inode
)->i_disksize
) {
1109 /* We need to mark inode dirty even if
1110 * new_i_size is less that inode->i_size
1111 * but greater than i_disksize. (hint delalloc)
1113 ext4_update_i_disksize(inode
, (pos
+ copied
));
1117 page_cache_release(page
);
1120 * Don't mark the inode dirty under page lock. First, it unnecessarily
1121 * makes the holding time of page lock longer. Second, it forces lock
1122 * ordering of page lock and transaction start for journaling
1126 ext4_mark_inode_dirty(handle
, inode
);
1128 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1129 /* if we have allocated more blocks and copied
1130 * less. We will have blocks allocated outside
1131 * inode->i_size. So truncate them
1133 ext4_orphan_add(handle
, inode
);
1135 ret2
= ext4_journal_stop(handle
);
1139 if (pos
+ len
> inode
->i_size
) {
1140 ext4_truncate_failed_write(inode
);
1142 * If truncate failed early the inode might still be
1143 * on the orphan list; we need to make sure the inode
1144 * is removed from the orphan list in that case.
1147 ext4_orphan_del(NULL
, inode
);
1150 return ret
? ret
: copied
;
1153 static int ext4_journalled_write_end(struct file
*file
,
1154 struct address_space
*mapping
,
1155 loff_t pos
, unsigned len
, unsigned copied
,
1156 struct page
*page
, void *fsdata
)
1158 handle_t
*handle
= ext4_journal_current_handle();
1159 struct inode
*inode
= mapping
->host
;
1165 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1166 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1169 BUG_ON(!ext4_handle_valid(handle
));
1171 if (ext4_has_inline_data(inode
))
1172 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1176 if (!PageUptodate(page
))
1178 page_zero_new_buffers(page
, from
+copied
, to
);
1181 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1182 to
, &partial
, write_end_fn
);
1184 SetPageUptodate(page
);
1186 new_i_size
= pos
+ copied
;
1187 if (new_i_size
> inode
->i_size
)
1188 i_size_write(inode
, pos
+copied
);
1189 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1190 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1191 if (new_i_size
> EXT4_I(inode
)->i_disksize
) {
1192 ext4_update_i_disksize(inode
, new_i_size
);
1193 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1199 page_cache_release(page
);
1200 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1201 /* if we have allocated more blocks and copied
1202 * less. We will have blocks allocated outside
1203 * inode->i_size. So truncate them
1205 ext4_orphan_add(handle
, inode
);
1207 ret2
= ext4_journal_stop(handle
);
1210 if (pos
+ len
> inode
->i_size
) {
1211 ext4_truncate_failed_write(inode
);
1213 * If truncate failed early the inode might still be
1214 * on the orphan list; we need to make sure the inode
1215 * is removed from the orphan list in that case.
1218 ext4_orphan_del(NULL
, inode
);
1221 return ret
? ret
: copied
;
1225 * Reserve a metadata for a single block located at lblock
1227 static int ext4_da_reserve_metadata(struct inode
*inode
, ext4_lblk_t lblock
)
1229 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1230 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1231 unsigned int md_needed
;
1232 ext4_lblk_t save_last_lblock
;
1236 * recalculate the amount of metadata blocks to reserve
1237 * in order to allocate nrblocks
1238 * worse case is one extent per block
1240 spin_lock(&ei
->i_block_reservation_lock
);
1242 * ext4_calc_metadata_amount() has side effects, which we have
1243 * to be prepared undo if we fail to claim space.
1245 save_len
= ei
->i_da_metadata_calc_len
;
1246 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1247 md_needed
= EXT4_NUM_B2C(sbi
,
1248 ext4_calc_metadata_amount(inode
, lblock
));
1249 trace_ext4_da_reserve_space(inode
, md_needed
);
1252 * We do still charge estimated metadata to the sb though;
1253 * we cannot afford to run out of free blocks.
1255 if (ext4_claim_free_clusters(sbi
, md_needed
, 0)) {
1256 ei
->i_da_metadata_calc_len
= save_len
;
1257 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1258 spin_unlock(&ei
->i_block_reservation_lock
);
1261 ei
->i_reserved_meta_blocks
+= md_needed
;
1262 spin_unlock(&ei
->i_block_reservation_lock
);
1264 return 0; /* success */
1268 * Reserve a single cluster located at lblock
1270 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1272 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1273 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1274 unsigned int md_needed
;
1276 ext4_lblk_t save_last_lblock
;
1280 * We will charge metadata quota at writeout time; this saves
1281 * us from metadata over-estimation, though we may go over by
1282 * a small amount in the end. Here we just reserve for data.
1284 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1289 * recalculate the amount of metadata blocks to reserve
1290 * in order to allocate nrblocks
1291 * worse case is one extent per block
1293 spin_lock(&ei
->i_block_reservation_lock
);
1295 * ext4_calc_metadata_amount() has side effects, which we have
1296 * to be prepared undo if we fail to claim space.
1298 save_len
= ei
->i_da_metadata_calc_len
;
1299 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1300 md_needed
= EXT4_NUM_B2C(sbi
,
1301 ext4_calc_metadata_amount(inode
, lblock
));
1302 trace_ext4_da_reserve_space(inode
, md_needed
);
1305 * We do still charge estimated metadata to the sb though;
1306 * we cannot afford to run out of free blocks.
1308 if (ext4_claim_free_clusters(sbi
, md_needed
+ 1, 0)) {
1309 ei
->i_da_metadata_calc_len
= save_len
;
1310 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1311 spin_unlock(&ei
->i_block_reservation_lock
);
1312 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1315 ei
->i_reserved_data_blocks
++;
1316 ei
->i_reserved_meta_blocks
+= md_needed
;
1317 spin_unlock(&ei
->i_block_reservation_lock
);
1319 return 0; /* success */
1322 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1324 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1325 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1328 return; /* Nothing to release, exit */
1330 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1332 trace_ext4_da_release_space(inode
, to_free
);
1333 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1335 * if there aren't enough reserved blocks, then the
1336 * counter is messed up somewhere. Since this
1337 * function is called from invalidate page, it's
1338 * harmless to return without any action.
1340 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1341 "ino %lu, to_free %d with only %d reserved "
1342 "data blocks", inode
->i_ino
, to_free
,
1343 ei
->i_reserved_data_blocks
);
1345 to_free
= ei
->i_reserved_data_blocks
;
1347 ei
->i_reserved_data_blocks
-= to_free
;
1349 if (ei
->i_reserved_data_blocks
== 0) {
1351 * We can release all of the reserved metadata blocks
1352 * only when we have written all of the delayed
1353 * allocation blocks.
1354 * Note that in case of bigalloc, i_reserved_meta_blocks,
1355 * i_reserved_data_blocks, etc. refer to number of clusters.
1357 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
1358 ei
->i_reserved_meta_blocks
);
1359 ei
->i_reserved_meta_blocks
= 0;
1360 ei
->i_da_metadata_calc_len
= 0;
1363 /* update fs dirty data blocks counter */
1364 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1366 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1368 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1371 static void ext4_da_page_release_reservation(struct page
*page
,
1372 unsigned int offset
,
1373 unsigned int length
)
1376 struct buffer_head
*head
, *bh
;
1377 unsigned int curr_off
= 0;
1378 struct inode
*inode
= page
->mapping
->host
;
1379 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1380 unsigned int stop
= offset
+ length
;
1384 BUG_ON(stop
> PAGE_CACHE_SIZE
|| stop
< length
);
1386 head
= page_buffers(page
);
1389 unsigned int next_off
= curr_off
+ bh
->b_size
;
1391 if (next_off
> stop
)
1394 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1396 clear_buffer_delay(bh
);
1398 curr_off
= next_off
;
1399 } while ((bh
= bh
->b_this_page
) != head
);
1402 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1403 ext4_es_remove_extent(inode
, lblk
, to_release
);
1406 /* If we have released all the blocks belonging to a cluster, then we
1407 * need to release the reserved space for that cluster. */
1408 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1409 while (num_clusters
> 0) {
1410 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1411 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1412 if (sbi
->s_cluster_ratio
== 1 ||
1413 !ext4_find_delalloc_cluster(inode
, lblk
))
1414 ext4_da_release_space(inode
, 1);
1421 * Delayed allocation stuff
1424 struct mpage_da_data
{
1425 struct inode
*inode
;
1426 struct writeback_control
*wbc
;
1428 pgoff_t first_page
; /* The first page to write */
1429 pgoff_t next_page
; /* Current page to examine */
1430 pgoff_t last_page
; /* Last page to examine */
1432 * Extent to map - this can be after first_page because that can be
1433 * fully mapped. We somewhat abuse m_flags to store whether the extent
1434 * is delalloc or unwritten.
1436 struct ext4_map_blocks map
;
1437 struct ext4_io_submit io_submit
; /* IO submission data */
1440 static void mpage_release_unused_pages(struct mpage_da_data
*mpd
,
1445 struct pagevec pvec
;
1446 struct inode
*inode
= mpd
->inode
;
1447 struct address_space
*mapping
= inode
->i_mapping
;
1449 /* This is necessary when next_page == 0. */
1450 if (mpd
->first_page
>= mpd
->next_page
)
1453 index
= mpd
->first_page
;
1454 end
= mpd
->next_page
- 1;
1456 ext4_lblk_t start
, last
;
1457 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1458 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1459 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1462 pagevec_init(&pvec
, 0);
1463 while (index
<= end
) {
1464 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1467 for (i
= 0; i
< nr_pages
; i
++) {
1468 struct page
*page
= pvec
.pages
[i
];
1469 if (page
->index
> end
)
1471 BUG_ON(!PageLocked(page
));
1472 BUG_ON(PageWriteback(page
));
1474 block_invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
1475 ClearPageUptodate(page
);
1479 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1480 pagevec_release(&pvec
);
1484 static void ext4_print_free_blocks(struct inode
*inode
)
1486 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1487 struct super_block
*sb
= inode
->i_sb
;
1488 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1490 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1491 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1492 ext4_count_free_clusters(sb
)));
1493 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1494 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1495 (long long) EXT4_C2B(EXT4_SB(sb
),
1496 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1497 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1498 (long long) EXT4_C2B(EXT4_SB(sb
),
1499 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1500 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1501 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1502 ei
->i_reserved_data_blocks
);
1503 ext4_msg(sb
, KERN_CRIT
, "i_reserved_meta_blocks=%u",
1504 ei
->i_reserved_meta_blocks
);
1505 ext4_msg(sb
, KERN_CRIT
, "i_allocated_meta_blocks=%u",
1506 ei
->i_allocated_meta_blocks
);
1510 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1512 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1516 * This function is grabs code from the very beginning of
1517 * ext4_map_blocks, but assumes that the caller is from delayed write
1518 * time. This function looks up the requested blocks and sets the
1519 * buffer delay bit under the protection of i_data_sem.
1521 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1522 struct ext4_map_blocks
*map
,
1523 struct buffer_head
*bh
)
1525 struct extent_status es
;
1527 sector_t invalid_block
= ~((sector_t
) 0xffff);
1528 #ifdef ES_AGGRESSIVE_TEST
1529 struct ext4_map_blocks orig_map
;
1531 memcpy(&orig_map
, map
, sizeof(*map
));
1534 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1538 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1539 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1540 (unsigned long) map
->m_lblk
);
1542 /* Lookup extent status tree firstly */
1543 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1544 ext4_es_lru_add(inode
);
1545 if (ext4_es_is_hole(&es
)) {
1547 down_read(&EXT4_I(inode
)->i_data_sem
);
1552 * Delayed extent could be allocated by fallocate.
1553 * So we need to check it.
1555 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1556 map_bh(bh
, inode
->i_sb
, invalid_block
);
1558 set_buffer_delay(bh
);
1562 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1563 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1564 if (retval
> map
->m_len
)
1565 retval
= map
->m_len
;
1566 map
->m_len
= retval
;
1567 if (ext4_es_is_written(&es
))
1568 map
->m_flags
|= EXT4_MAP_MAPPED
;
1569 else if (ext4_es_is_unwritten(&es
))
1570 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1574 #ifdef ES_AGGRESSIVE_TEST
1575 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1581 * Try to see if we can get the block without requesting a new
1582 * file system block.
1584 down_read(&EXT4_I(inode
)->i_data_sem
);
1585 if (ext4_has_inline_data(inode
)) {
1587 * We will soon create blocks for this page, and let
1588 * us pretend as if the blocks aren't allocated yet.
1589 * In case of clusters, we have to handle the work
1590 * of mapping from cluster so that the reserved space
1591 * is calculated properly.
1593 if ((EXT4_SB(inode
->i_sb
)->s_cluster_ratio
> 1) &&
1594 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
1595 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
1597 } else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1598 retval
= ext4_ext_map_blocks(NULL
, inode
, map
,
1599 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1601 retval
= ext4_ind_map_blocks(NULL
, inode
, map
,
1602 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1608 * XXX: __block_prepare_write() unmaps passed block,
1612 * If the block was allocated from previously allocated cluster,
1613 * then we don't need to reserve it again. However we still need
1614 * to reserve metadata for every block we're going to write.
1616 if (!(map
->m_flags
& EXT4_MAP_FROM_CLUSTER
)) {
1617 ret
= ext4_da_reserve_space(inode
, iblock
);
1619 /* not enough space to reserve */
1624 ret
= ext4_da_reserve_metadata(inode
, iblock
);
1626 /* not enough space to reserve */
1632 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1633 ~0, EXTENT_STATUS_DELAYED
);
1639 /* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
1640 * and it should not appear on the bh->b_state.
1642 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
1644 map_bh(bh
, inode
->i_sb
, invalid_block
);
1646 set_buffer_delay(bh
);
1647 } else if (retval
> 0) {
1649 unsigned int status
;
1651 if (unlikely(retval
!= map
->m_len
)) {
1652 ext4_warning(inode
->i_sb
,
1653 "ES len assertion failed for inode "
1654 "%lu: retval %d != map->m_len %d",
1655 inode
->i_ino
, retval
, map
->m_len
);
1659 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
1660 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
1661 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1662 map
->m_pblk
, status
);
1668 up_read((&EXT4_I(inode
)->i_data_sem
));
1674 * This is a special get_blocks_t callback which is used by
1675 * ext4_da_write_begin(). It will either return mapped block or
1676 * reserve space for a single block.
1678 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
1679 * We also have b_blocknr = -1 and b_bdev initialized properly
1681 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
1682 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
1683 * initialized properly.
1685 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
1686 struct buffer_head
*bh
, int create
)
1688 struct ext4_map_blocks map
;
1691 BUG_ON(create
== 0);
1692 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
1694 map
.m_lblk
= iblock
;
1698 * first, we need to know whether the block is allocated already
1699 * preallocated blocks are unmapped but should treated
1700 * the same as allocated blocks.
1702 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
1706 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
1707 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
1709 if (buffer_unwritten(bh
)) {
1710 /* A delayed write to unwritten bh should be marked
1711 * new and mapped. Mapped ensures that we don't do
1712 * get_block multiple times when we write to the same
1713 * offset and new ensures that we do proper zero out
1714 * for partial write.
1717 set_buffer_mapped(bh
);
1722 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1728 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1734 static int __ext4_journalled_writepage(struct page
*page
,
1737 struct address_space
*mapping
= page
->mapping
;
1738 struct inode
*inode
= mapping
->host
;
1739 struct buffer_head
*page_bufs
= NULL
;
1740 handle_t
*handle
= NULL
;
1741 int ret
= 0, err
= 0;
1742 int inline_data
= ext4_has_inline_data(inode
);
1743 struct buffer_head
*inode_bh
= NULL
;
1745 ClearPageChecked(page
);
1748 BUG_ON(page
->index
!= 0);
1749 BUG_ON(len
> ext4_get_max_inline_size(inode
));
1750 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
1751 if (inode_bh
== NULL
)
1754 page_bufs
= page_buffers(page
);
1759 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
1762 /* As soon as we unlock the page, it can go away, but we have
1763 * references to buffers so we are safe */
1766 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
1767 ext4_writepage_trans_blocks(inode
));
1768 if (IS_ERR(handle
)) {
1769 ret
= PTR_ERR(handle
);
1773 BUG_ON(!ext4_handle_valid(handle
));
1776 BUFFER_TRACE(inode_bh
, "get write access");
1777 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
1779 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
1782 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1783 do_journal_get_write_access
);
1785 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1790 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1791 err
= ext4_journal_stop(handle
);
1795 if (!ext4_has_inline_data(inode
))
1796 ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
,
1798 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1805 * Note that we don't need to start a transaction unless we're journaling data
1806 * because we should have holes filled from ext4_page_mkwrite(). We even don't
1807 * need to file the inode to the transaction's list in ordered mode because if
1808 * we are writing back data added by write(), the inode is already there and if
1809 * we are writing back data modified via mmap(), no one guarantees in which
1810 * transaction the data will hit the disk. In case we are journaling data, we
1811 * cannot start transaction directly because transaction start ranks above page
1812 * lock so we have to do some magic.
1814 * This function can get called via...
1815 * - ext4_writepages after taking page lock (have journal handle)
1816 * - journal_submit_inode_data_buffers (no journal handle)
1817 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
1818 * - grab_page_cache when doing write_begin (have journal handle)
1820 * We don't do any block allocation in this function. If we have page with
1821 * multiple blocks we need to write those buffer_heads that are mapped. This
1822 * is important for mmaped based write. So if we do with blocksize 1K
1823 * truncate(f, 1024);
1824 * a = mmap(f, 0, 4096);
1826 * truncate(f, 4096);
1827 * we have in the page first buffer_head mapped via page_mkwrite call back
1828 * but other buffer_heads would be unmapped but dirty (dirty done via the
1829 * do_wp_page). So writepage should write the first block. If we modify
1830 * the mmap area beyond 1024 we will again get a page_fault and the
1831 * page_mkwrite callback will do the block allocation and mark the
1832 * buffer_heads mapped.
1834 * We redirty the page if we have any buffer_heads that is either delay or
1835 * unwritten in the page.
1837 * We can get recursively called as show below.
1839 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1842 * But since we don't do any block allocation we should not deadlock.
1843 * Page also have the dirty flag cleared so we don't get recurive page_lock.
1845 static int ext4_writepage(struct page
*page
,
1846 struct writeback_control
*wbc
)
1851 struct buffer_head
*page_bufs
= NULL
;
1852 struct inode
*inode
= page
->mapping
->host
;
1853 struct ext4_io_submit io_submit
;
1854 bool keep_towrite
= false;
1856 trace_ext4_writepage(page
);
1857 size
= i_size_read(inode
);
1858 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1859 len
= size
& ~PAGE_CACHE_MASK
;
1861 len
= PAGE_CACHE_SIZE
;
1863 page_bufs
= page_buffers(page
);
1865 * We cannot do block allocation or other extent handling in this
1866 * function. If there are buffers needing that, we have to redirty
1867 * the page. But we may reach here when we do a journal commit via
1868 * journal_submit_inode_data_buffers() and in that case we must write
1869 * allocated buffers to achieve data=ordered mode guarantees.
1871 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
1872 ext4_bh_delay_or_unwritten
)) {
1873 redirty_page_for_writepage(wbc
, page
);
1874 if (current
->flags
& PF_MEMALLOC
) {
1876 * For memory cleaning there's no point in writing only
1877 * some buffers. So just bail out. Warn if we came here
1878 * from direct reclaim.
1880 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
1885 keep_towrite
= true;
1888 if (PageChecked(page
) && ext4_should_journal_data(inode
))
1890 * It's mmapped pagecache. Add buffers and journal it. There
1891 * doesn't seem much point in redirtying the page here.
1893 return __ext4_journalled_writepage(page
, len
);
1895 ext4_io_submit_init(&io_submit
, wbc
);
1896 io_submit
.io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
1897 if (!io_submit
.io_end
) {
1898 redirty_page_for_writepage(wbc
, page
);
1902 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
, keep_towrite
);
1903 ext4_io_submit(&io_submit
);
1904 /* Drop io_end reference we got from init */
1905 ext4_put_io_end_defer(io_submit
.io_end
);
1909 static int mpage_submit_page(struct mpage_da_data
*mpd
, struct page
*page
)
1912 loff_t size
= i_size_read(mpd
->inode
);
1915 BUG_ON(page
->index
!= mpd
->first_page
);
1916 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1917 len
= size
& ~PAGE_CACHE_MASK
;
1919 len
= PAGE_CACHE_SIZE
;
1920 clear_page_dirty_for_io(page
);
1921 err
= ext4_bio_write_page(&mpd
->io_submit
, page
, len
, mpd
->wbc
, false);
1923 mpd
->wbc
->nr_to_write
--;
1929 #define BH_FLAGS ((1 << BH_Unwritten) | (1 << BH_Delay))
1932 * mballoc gives us at most this number of blocks...
1933 * XXX: That seems to be only a limitation of ext4_mb_normalize_request().
1934 * The rest of mballoc seems to handle chunks up to full group size.
1936 #define MAX_WRITEPAGES_EXTENT_LEN 2048
1939 * mpage_add_bh_to_extent - try to add bh to extent of blocks to map
1941 * @mpd - extent of blocks
1942 * @lblk - logical number of the block in the file
1943 * @bh - buffer head we want to add to the extent
1945 * The function is used to collect contig. blocks in the same state. If the
1946 * buffer doesn't require mapping for writeback and we haven't started the
1947 * extent of buffers to map yet, the function returns 'true' immediately - the
1948 * caller can write the buffer right away. Otherwise the function returns true
1949 * if the block has been added to the extent, false if the block couldn't be
1952 static bool mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, ext4_lblk_t lblk
,
1953 struct buffer_head
*bh
)
1955 struct ext4_map_blocks
*map
= &mpd
->map
;
1957 /* Buffer that doesn't need mapping for writeback? */
1958 if (!buffer_dirty(bh
) || !buffer_mapped(bh
) ||
1959 (!buffer_delay(bh
) && !buffer_unwritten(bh
))) {
1960 /* So far no extent to map => we write the buffer right away */
1961 if (map
->m_len
== 0)
1966 /* First block in the extent? */
1967 if (map
->m_len
== 0) {
1970 map
->m_flags
= bh
->b_state
& BH_FLAGS
;
1974 /* Don't go larger than mballoc is willing to allocate */
1975 if (map
->m_len
>= MAX_WRITEPAGES_EXTENT_LEN
)
1978 /* Can we merge the block to our big extent? */
1979 if (lblk
== map
->m_lblk
+ map
->m_len
&&
1980 (bh
->b_state
& BH_FLAGS
) == map
->m_flags
) {
1988 * mpage_process_page_bufs - submit page buffers for IO or add them to extent
1990 * @mpd - extent of blocks for mapping
1991 * @head - the first buffer in the page
1992 * @bh - buffer we should start processing from
1993 * @lblk - logical number of the block in the file corresponding to @bh
1995 * Walk through page buffers from @bh upto @head (exclusive) and either submit
1996 * the page for IO if all buffers in this page were mapped and there's no
1997 * accumulated extent of buffers to map or add buffers in the page to the
1998 * extent of buffers to map. The function returns 1 if the caller can continue
1999 * by processing the next page, 0 if it should stop adding buffers to the
2000 * extent to map because we cannot extend it anymore. It can also return value
2001 * < 0 in case of error during IO submission.
2003 static int mpage_process_page_bufs(struct mpage_da_data
*mpd
,
2004 struct buffer_head
*head
,
2005 struct buffer_head
*bh
,
2008 struct inode
*inode
= mpd
->inode
;
2010 ext4_lblk_t blocks
= (i_size_read(inode
) + (1 << inode
->i_blkbits
) - 1)
2011 >> inode
->i_blkbits
;
2014 BUG_ON(buffer_locked(bh
));
2016 if (lblk
>= blocks
|| !mpage_add_bh_to_extent(mpd
, lblk
, bh
)) {
2017 /* Found extent to map? */
2020 /* Everything mapped so far and we hit EOF */
2023 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
2024 /* So far everything mapped? Submit the page for IO. */
2025 if (mpd
->map
.m_len
== 0) {
2026 err
= mpage_submit_page(mpd
, head
->b_page
);
2030 return lblk
< blocks
;
2034 * mpage_map_buffers - update buffers corresponding to changed extent and
2035 * submit fully mapped pages for IO
2037 * @mpd - description of extent to map, on return next extent to map
2039 * Scan buffers corresponding to changed extent (we expect corresponding pages
2040 * to be already locked) and update buffer state according to new extent state.
2041 * We map delalloc buffers to their physical location, clear unwritten bits,
2042 * and mark buffers as uninit when we perform writes to unwritten extents
2043 * and do extent conversion after IO is finished. If the last page is not fully
2044 * mapped, we update @map to the next extent in the last page that needs
2045 * mapping. Otherwise we submit the page for IO.
2047 static int mpage_map_and_submit_buffers(struct mpage_da_data
*mpd
)
2049 struct pagevec pvec
;
2051 struct inode
*inode
= mpd
->inode
;
2052 struct buffer_head
*head
, *bh
;
2053 int bpp_bits
= PAGE_CACHE_SHIFT
- inode
->i_blkbits
;
2059 start
= mpd
->map
.m_lblk
>> bpp_bits
;
2060 end
= (mpd
->map
.m_lblk
+ mpd
->map
.m_len
- 1) >> bpp_bits
;
2061 lblk
= start
<< bpp_bits
;
2062 pblock
= mpd
->map
.m_pblk
;
2064 pagevec_init(&pvec
, 0);
2065 while (start
<= end
) {
2066 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, start
,
2070 for (i
= 0; i
< nr_pages
; i
++) {
2071 struct page
*page
= pvec
.pages
[i
];
2073 if (page
->index
> end
)
2075 /* Up to 'end' pages must be contiguous */
2076 BUG_ON(page
->index
!= start
);
2077 bh
= head
= page_buffers(page
);
2079 if (lblk
< mpd
->map
.m_lblk
)
2081 if (lblk
>= mpd
->map
.m_lblk
+ mpd
->map
.m_len
) {
2083 * Buffer after end of mapped extent.
2084 * Find next buffer in the page to map.
2087 mpd
->map
.m_flags
= 0;
2089 * FIXME: If dioread_nolock supports
2090 * blocksize < pagesize, we need to make
2091 * sure we add size mapped so far to
2092 * io_end->size as the following call
2093 * can submit the page for IO.
2095 err
= mpage_process_page_bufs(mpd
, head
,
2097 pagevec_release(&pvec
);
2102 if (buffer_delay(bh
)) {
2103 clear_buffer_delay(bh
);
2104 bh
->b_blocknr
= pblock
++;
2106 clear_buffer_unwritten(bh
);
2107 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
2110 * FIXME: This is going to break if dioread_nolock
2111 * supports blocksize < pagesize as we will try to
2112 * convert potentially unmapped parts of inode.
2114 mpd
->io_submit
.io_end
->size
+= PAGE_CACHE_SIZE
;
2115 /* Page fully mapped - let IO run! */
2116 err
= mpage_submit_page(mpd
, page
);
2118 pagevec_release(&pvec
);
2123 pagevec_release(&pvec
);
2125 /* Extent fully mapped and matches with page boundary. We are done. */
2127 mpd
->map
.m_flags
= 0;
2131 static int mpage_map_one_extent(handle_t
*handle
, struct mpage_da_data
*mpd
)
2133 struct inode
*inode
= mpd
->inode
;
2134 struct ext4_map_blocks
*map
= &mpd
->map
;
2135 int get_blocks_flags
;
2136 int err
, dioread_nolock
;
2138 trace_ext4_da_write_pages_extent(inode
, map
);
2140 * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
2141 * to convert an unwritten extent to be initialized (in the case
2142 * where we have written into one or more preallocated blocks). It is
2143 * possible that we're going to need more metadata blocks than
2144 * previously reserved. However we must not fail because we're in
2145 * writeback and there is nothing we can do about it so it might result
2146 * in data loss. So use reserved blocks to allocate metadata if
2149 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if the blocks
2150 * in question are delalloc blocks. This affects functions in many
2151 * different parts of the allocation call path. This flag exists
2152 * primarily because we don't want to change *many* call functions, so
2153 * ext4_map_blocks() will set the EXT4_STATE_DELALLOC_RESERVED flag
2154 * once the inode's allocation semaphore is taken.
2156 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
2157 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
2158 dioread_nolock
= ext4_should_dioread_nolock(inode
);
2160 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
2161 if (map
->m_flags
& (1 << BH_Delay
))
2162 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
2164 err
= ext4_map_blocks(handle
, inode
, map
, get_blocks_flags
);
2167 if (dioread_nolock
&& (map
->m_flags
& EXT4_MAP_UNWRITTEN
)) {
2168 if (!mpd
->io_submit
.io_end
->handle
&&
2169 ext4_handle_valid(handle
)) {
2170 mpd
->io_submit
.io_end
->handle
= handle
->h_rsv_handle
;
2171 handle
->h_rsv_handle
= NULL
;
2173 ext4_set_io_unwritten_flag(inode
, mpd
->io_submit
.io_end
);
2176 BUG_ON(map
->m_len
== 0);
2177 if (map
->m_flags
& EXT4_MAP_NEW
) {
2178 struct block_device
*bdev
= inode
->i_sb
->s_bdev
;
2181 for (i
= 0; i
< map
->m_len
; i
++)
2182 unmap_underlying_metadata(bdev
, map
->m_pblk
+ i
);
2188 * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
2189 * mpd->len and submit pages underlying it for IO
2191 * @handle - handle for journal operations
2192 * @mpd - extent to map
2193 * @give_up_on_write - we set this to true iff there is a fatal error and there
2194 * is no hope of writing the data. The caller should discard
2195 * dirty pages to avoid infinite loops.
2197 * The function maps extent starting at mpd->lblk of length mpd->len. If it is
2198 * delayed, blocks are allocated, if it is unwritten, we may need to convert
2199 * them to initialized or split the described range from larger unwritten
2200 * extent. Note that we need not map all the described range since allocation
2201 * can return less blocks or the range is covered by more unwritten extents. We
2202 * cannot map more because we are limited by reserved transaction credits. On
2203 * the other hand we always make sure that the last touched page is fully
2204 * mapped so that it can be written out (and thus forward progress is
2205 * guaranteed). After mapping we submit all mapped pages for IO.
2207 static int mpage_map_and_submit_extent(handle_t
*handle
,
2208 struct mpage_da_data
*mpd
,
2209 bool *give_up_on_write
)
2211 struct inode
*inode
= mpd
->inode
;
2212 struct ext4_map_blocks
*map
= &mpd
->map
;
2216 mpd
->io_submit
.io_end
->offset
=
2217 ((loff_t
)map
->m_lblk
) << inode
->i_blkbits
;
2219 err
= mpage_map_one_extent(handle
, mpd
);
2221 struct super_block
*sb
= inode
->i_sb
;
2223 if (EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)
2224 goto invalidate_dirty_pages
;
2226 * Let the uper layers retry transient errors.
2227 * In the case of ENOSPC, if ext4_count_free_blocks()
2228 * is non-zero, a commit should free up blocks.
2230 if ((err
== -ENOMEM
) ||
2231 (err
== -ENOSPC
&& ext4_count_free_clusters(sb
)))
2233 ext4_msg(sb
, KERN_CRIT
,
2234 "Delayed block allocation failed for "
2235 "inode %lu at logical offset %llu with"
2236 " max blocks %u with error %d",
2238 (unsigned long long)map
->m_lblk
,
2239 (unsigned)map
->m_len
, -err
);
2240 ext4_msg(sb
, KERN_CRIT
,
2241 "This should not happen!! Data will "
2244 ext4_print_free_blocks(inode
);
2245 invalidate_dirty_pages
:
2246 *give_up_on_write
= true;
2250 * Update buffer state, submit mapped pages, and get us new
2253 err
= mpage_map_and_submit_buffers(mpd
);
2256 } while (map
->m_len
);
2259 * Update on-disk size after IO is submitted. Races with
2260 * truncate are avoided by checking i_size under i_data_sem.
2262 disksize
= ((loff_t
)mpd
->first_page
) << PAGE_CACHE_SHIFT
;
2263 if (disksize
> EXT4_I(inode
)->i_disksize
) {
2267 down_write(&EXT4_I(inode
)->i_data_sem
);
2268 i_size
= i_size_read(inode
);
2269 if (disksize
> i_size
)
2271 if (disksize
> EXT4_I(inode
)->i_disksize
)
2272 EXT4_I(inode
)->i_disksize
= disksize
;
2273 err2
= ext4_mark_inode_dirty(handle
, inode
);
2274 up_write(&EXT4_I(inode
)->i_data_sem
);
2276 ext4_error(inode
->i_sb
,
2277 "Failed to mark inode %lu dirty",
2286 * Calculate the total number of credits to reserve for one writepages
2287 * iteration. This is called from ext4_writepages(). We map an extent of
2288 * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
2289 * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
2290 * bpp - 1 blocks in bpp different extents.
2292 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2294 int bpp
= ext4_journal_blocks_per_page(inode
);
2296 return ext4_meta_trans_blocks(inode
,
2297 MAX_WRITEPAGES_EXTENT_LEN
+ bpp
- 1, bpp
);
2301 * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
2302 * and underlying extent to map
2304 * @mpd - where to look for pages
2306 * Walk dirty pages in the mapping. If they are fully mapped, submit them for
2307 * IO immediately. When we find a page which isn't mapped we start accumulating
2308 * extent of buffers underlying these pages that needs mapping (formed by
2309 * either delayed or unwritten buffers). We also lock the pages containing
2310 * these buffers. The extent found is returned in @mpd structure (starting at
2311 * mpd->lblk with length mpd->len blocks).
2313 * Note that this function can attach bios to one io_end structure which are
2314 * neither logically nor physically contiguous. Although it may seem as an
2315 * unnecessary complication, it is actually inevitable in blocksize < pagesize
2316 * case as we need to track IO to all buffers underlying a page in one io_end.
2318 static int mpage_prepare_extent_to_map(struct mpage_da_data
*mpd
)
2320 struct address_space
*mapping
= mpd
->inode
->i_mapping
;
2321 struct pagevec pvec
;
2322 unsigned int nr_pages
;
2323 long left
= mpd
->wbc
->nr_to_write
;
2324 pgoff_t index
= mpd
->first_page
;
2325 pgoff_t end
= mpd
->last_page
;
2328 int blkbits
= mpd
->inode
->i_blkbits
;
2330 struct buffer_head
*head
;
2332 if (mpd
->wbc
->sync_mode
== WB_SYNC_ALL
|| mpd
->wbc
->tagged_writepages
)
2333 tag
= PAGECACHE_TAG_TOWRITE
;
2335 tag
= PAGECACHE_TAG_DIRTY
;
2337 pagevec_init(&pvec
, 0);
2339 mpd
->next_page
= index
;
2340 while (index
<= end
) {
2341 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2342 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2346 for (i
= 0; i
< nr_pages
; i
++) {
2347 struct page
*page
= pvec
.pages
[i
];
2350 * At this point, the page may be truncated or
2351 * invalidated (changing page->mapping to NULL), or
2352 * even swizzled back from swapper_space to tmpfs file
2353 * mapping. However, page->index will not change
2354 * because we have a reference on the page.
2356 if (page
->index
> end
)
2360 * Accumulated enough dirty pages? This doesn't apply
2361 * to WB_SYNC_ALL mode. For integrity sync we have to
2362 * keep going because someone may be concurrently
2363 * dirtying pages, and we might have synced a lot of
2364 * newly appeared dirty pages, but have not synced all
2365 * of the old dirty pages.
2367 if (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
&& left
<= 0)
2370 /* If we can't merge this page, we are done. */
2371 if (mpd
->map
.m_len
> 0 && mpd
->next_page
!= page
->index
)
2376 * If the page is no longer dirty, or its mapping no
2377 * longer corresponds to inode we are writing (which
2378 * means it has been truncated or invalidated), or the
2379 * page is already under writeback and we are not doing
2380 * a data integrity writeback, skip the page
2382 if (!PageDirty(page
) ||
2383 (PageWriteback(page
) &&
2384 (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2385 unlikely(page
->mapping
!= mapping
)) {
2390 wait_on_page_writeback(page
);
2391 BUG_ON(PageWriteback(page
));
2393 if (mpd
->map
.m_len
== 0)
2394 mpd
->first_page
= page
->index
;
2395 mpd
->next_page
= page
->index
+ 1;
2396 /* Add all dirty buffers to mpd */
2397 lblk
= ((ext4_lblk_t
)page
->index
) <<
2398 (PAGE_CACHE_SHIFT
- blkbits
);
2399 head
= page_buffers(page
);
2400 err
= mpage_process_page_bufs(mpd
, head
, head
, lblk
);
2406 pagevec_release(&pvec
);
2411 pagevec_release(&pvec
);
2415 static int __writepage(struct page
*page
, struct writeback_control
*wbc
,
2418 struct address_space
*mapping
= data
;
2419 int ret
= ext4_writepage(page
, wbc
);
2420 mapping_set_error(mapping
, ret
);
2424 static int ext4_writepages(struct address_space
*mapping
,
2425 struct writeback_control
*wbc
)
2427 pgoff_t writeback_index
= 0;
2428 long nr_to_write
= wbc
->nr_to_write
;
2429 int range_whole
= 0;
2431 handle_t
*handle
= NULL
;
2432 struct mpage_da_data mpd
;
2433 struct inode
*inode
= mapping
->host
;
2434 int needed_blocks
, rsv_blocks
= 0, ret
= 0;
2435 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2437 struct blk_plug plug
;
2438 bool give_up_on_write
= false;
2440 trace_ext4_writepages(inode
, wbc
);
2443 * No pages to write? This is mainly a kludge to avoid starting
2444 * a transaction for special inodes like journal inode on last iput()
2445 * because that could violate lock ordering on umount
2447 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2448 goto out_writepages
;
2450 if (ext4_should_journal_data(inode
)) {
2451 struct blk_plug plug
;
2453 blk_start_plug(&plug
);
2454 ret
= write_cache_pages(mapping
, wbc
, __writepage
, mapping
);
2455 blk_finish_plug(&plug
);
2456 goto out_writepages
;
2460 * If the filesystem has aborted, it is read-only, so return
2461 * right away instead of dumping stack traces later on that
2462 * will obscure the real source of the problem. We test
2463 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2464 * the latter could be true if the filesystem is mounted
2465 * read-only, and in that case, ext4_writepages should
2466 * *never* be called, so if that ever happens, we would want
2469 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
2471 goto out_writepages
;
2474 if (ext4_should_dioread_nolock(inode
)) {
2476 * We may need to convert up to one extent per block in
2477 * the page and we may dirty the inode.
2479 rsv_blocks
= 1 + (PAGE_CACHE_SIZE
>> inode
->i_blkbits
);
2483 * If we have inline data and arrive here, it means that
2484 * we will soon create the block for the 1st page, so
2485 * we'd better clear the inline data here.
2487 if (ext4_has_inline_data(inode
)) {
2488 /* Just inode will be modified... */
2489 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
2490 if (IS_ERR(handle
)) {
2491 ret
= PTR_ERR(handle
);
2492 goto out_writepages
;
2494 BUG_ON(ext4_test_inode_state(inode
,
2495 EXT4_STATE_MAY_INLINE_DATA
));
2496 ext4_destroy_inline_data(handle
, inode
);
2497 ext4_journal_stop(handle
);
2500 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2503 if (wbc
->range_cyclic
) {
2504 writeback_index
= mapping
->writeback_index
;
2505 if (writeback_index
)
2507 mpd
.first_page
= writeback_index
;
2510 mpd
.first_page
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2511 mpd
.last_page
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2516 ext4_io_submit_init(&mpd
.io_submit
, wbc
);
2518 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2519 tag_pages_for_writeback(mapping
, mpd
.first_page
, mpd
.last_page
);
2521 blk_start_plug(&plug
);
2522 while (!done
&& mpd
.first_page
<= mpd
.last_page
) {
2523 /* For each extent of pages we use new io_end */
2524 mpd
.io_submit
.io_end
= ext4_init_io_end(inode
, GFP_KERNEL
);
2525 if (!mpd
.io_submit
.io_end
) {
2531 * We have two constraints: We find one extent to map and we
2532 * must always write out whole page (makes a difference when
2533 * blocksize < pagesize) so that we don't block on IO when we
2534 * try to write out the rest of the page. Journalled mode is
2535 * not supported by delalloc.
2537 BUG_ON(ext4_should_journal_data(inode
));
2538 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2540 /* start a new transaction */
2541 handle
= ext4_journal_start_with_reserve(inode
,
2542 EXT4_HT_WRITE_PAGE
, needed_blocks
, rsv_blocks
);
2543 if (IS_ERR(handle
)) {
2544 ret
= PTR_ERR(handle
);
2545 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2546 "%ld pages, ino %lu; err %d", __func__
,
2547 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2548 /* Release allocated io_end */
2549 ext4_put_io_end(mpd
.io_submit
.io_end
);
2553 trace_ext4_da_write_pages(inode
, mpd
.first_page
, mpd
.wbc
);
2554 ret
= mpage_prepare_extent_to_map(&mpd
);
2557 ret
= mpage_map_and_submit_extent(handle
, &mpd
,
2561 * We scanned the whole range (or exhausted
2562 * nr_to_write), submitted what was mapped and
2563 * didn't find anything needing mapping. We are
2569 ext4_journal_stop(handle
);
2570 /* Submit prepared bio */
2571 ext4_io_submit(&mpd
.io_submit
);
2572 /* Unlock pages we didn't use */
2573 mpage_release_unused_pages(&mpd
, give_up_on_write
);
2574 /* Drop our io_end reference we got from init */
2575 ext4_put_io_end(mpd
.io_submit
.io_end
);
2577 if (ret
== -ENOSPC
&& sbi
->s_journal
) {
2579 * Commit the transaction which would
2580 * free blocks released in the transaction
2583 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2587 /* Fatal error - ENOMEM, EIO... */
2591 blk_finish_plug(&plug
);
2592 if (!ret
&& !cycled
&& wbc
->nr_to_write
> 0) {
2594 mpd
.last_page
= writeback_index
- 1;
2600 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2602 * Set the writeback_index so that range_cyclic
2603 * mode will write it back later
2605 mapping
->writeback_index
= mpd
.first_page
;
2608 trace_ext4_writepages_result(inode
, wbc
, ret
,
2609 nr_to_write
- wbc
->nr_to_write
);
2613 static int ext4_nonda_switch(struct super_block
*sb
)
2615 s64 free_clusters
, dirty_clusters
;
2616 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2619 * switch to non delalloc mode if we are running low
2620 * on free block. The free block accounting via percpu
2621 * counters can get slightly wrong with percpu_counter_batch getting
2622 * accumulated on each CPU without updating global counters
2623 * Delalloc need an accurate free block accounting. So switch
2624 * to non delalloc when we are near to error range.
2627 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2629 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2631 * Start pushing delalloc when 1/2 of free blocks are dirty.
2633 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2634 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2636 if (2 * free_clusters
< 3 * dirty_clusters
||
2637 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2639 * free block count is less than 150% of dirty blocks
2640 * or free blocks is less than watermark
2647 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2648 loff_t pos
, unsigned len
, unsigned flags
,
2649 struct page
**pagep
, void **fsdata
)
2651 int ret
, retries
= 0;
2654 struct inode
*inode
= mapping
->host
;
2657 index
= pos
>> PAGE_CACHE_SHIFT
;
2659 if (ext4_nonda_switch(inode
->i_sb
)) {
2660 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2661 return ext4_write_begin(file
, mapping
, pos
,
2662 len
, flags
, pagep
, fsdata
);
2664 *fsdata
= (void *)0;
2665 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2667 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2668 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2678 * grab_cache_page_write_begin() can take a long time if the
2679 * system is thrashing due to memory pressure, or if the page
2680 * is being written back. So grab it first before we start
2681 * the transaction handle. This also allows us to allocate
2682 * the page (if needed) without using GFP_NOFS.
2685 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2691 * With delayed allocation, we don't log the i_disksize update
2692 * if there is delayed block allocation. But we still need
2693 * to journalling the i_disksize update if writes to the end
2694 * of file which has an already mapped buffer.
2697 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, 1);
2698 if (IS_ERR(handle
)) {
2699 page_cache_release(page
);
2700 return PTR_ERR(handle
);
2704 if (page
->mapping
!= mapping
) {
2705 /* The page got truncated from under us */
2707 page_cache_release(page
);
2708 ext4_journal_stop(handle
);
2711 /* In case writeback began while the page was unlocked */
2712 wait_for_stable_page(page
);
2714 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2717 ext4_journal_stop(handle
);
2719 * block_write_begin may have instantiated a few blocks
2720 * outside i_size. Trim these off again. Don't need
2721 * i_size_read because we hold i_mutex.
2723 if (pos
+ len
> inode
->i_size
)
2724 ext4_truncate_failed_write(inode
);
2726 if (ret
== -ENOSPC
&&
2727 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2730 page_cache_release(page
);
2739 * Check if we should update i_disksize
2740 * when write to the end of file but not require block allocation
2742 static int ext4_da_should_update_i_disksize(struct page
*page
,
2743 unsigned long offset
)
2745 struct buffer_head
*bh
;
2746 struct inode
*inode
= page
->mapping
->host
;
2750 bh
= page_buffers(page
);
2751 idx
= offset
>> inode
->i_blkbits
;
2753 for (i
= 0; i
< idx
; i
++)
2754 bh
= bh
->b_this_page
;
2756 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2761 static int ext4_da_write_end(struct file
*file
,
2762 struct address_space
*mapping
,
2763 loff_t pos
, unsigned len
, unsigned copied
,
2764 struct page
*page
, void *fsdata
)
2766 struct inode
*inode
= mapping
->host
;
2768 handle_t
*handle
= ext4_journal_current_handle();
2770 unsigned long start
, end
;
2771 int write_mode
= (int)(unsigned long)fsdata
;
2773 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2774 return ext4_write_end(file
, mapping
, pos
,
2775 len
, copied
, page
, fsdata
);
2777 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2778 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2779 end
= start
+ copied
- 1;
2782 * generic_write_end() will run mark_inode_dirty() if i_size
2783 * changes. So let's piggyback the i_disksize mark_inode_dirty
2786 new_i_size
= pos
+ copied
;
2787 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2788 if (ext4_has_inline_data(inode
) ||
2789 ext4_da_should_update_i_disksize(page
, end
)) {
2790 down_write(&EXT4_I(inode
)->i_data_sem
);
2791 if (new_i_size
> EXT4_I(inode
)->i_disksize
)
2792 EXT4_I(inode
)->i_disksize
= new_i_size
;
2793 up_write(&EXT4_I(inode
)->i_data_sem
);
2794 /* We need to mark inode dirty even if
2795 * new_i_size is less that inode->i_size
2796 * bu greater than i_disksize.(hint delalloc)
2798 ext4_mark_inode_dirty(handle
, inode
);
2802 if (write_mode
!= CONVERT_INLINE_DATA
&&
2803 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2804 ext4_has_inline_data(inode
))
2805 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2808 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2814 ret2
= ext4_journal_stop(handle
);
2818 return ret
? ret
: copied
;
2821 static void ext4_da_invalidatepage(struct page
*page
, unsigned int offset
,
2822 unsigned int length
)
2825 * Drop reserved blocks
2827 BUG_ON(!PageLocked(page
));
2828 if (!page_has_buffers(page
))
2831 ext4_da_page_release_reservation(page
, offset
, length
);
2834 ext4_invalidatepage(page
, offset
, length
);
2840 * Force all delayed allocation blocks to be allocated for a given inode.
2842 int ext4_alloc_da_blocks(struct inode
*inode
)
2844 trace_ext4_alloc_da_blocks(inode
);
2846 if (!EXT4_I(inode
)->i_reserved_data_blocks
&&
2847 !EXT4_I(inode
)->i_reserved_meta_blocks
)
2851 * We do something simple for now. The filemap_flush() will
2852 * also start triggering a write of the data blocks, which is
2853 * not strictly speaking necessary (and for users of
2854 * laptop_mode, not even desirable). However, to do otherwise
2855 * would require replicating code paths in:
2857 * ext4_writepages() ->
2858 * write_cache_pages() ---> (via passed in callback function)
2859 * __mpage_da_writepage() -->
2860 * mpage_add_bh_to_extent()
2861 * mpage_da_map_blocks()
2863 * The problem is that write_cache_pages(), located in
2864 * mm/page-writeback.c, marks pages clean in preparation for
2865 * doing I/O, which is not desirable if we're not planning on
2868 * We could call write_cache_pages(), and then redirty all of
2869 * the pages by calling redirty_page_for_writepage() but that
2870 * would be ugly in the extreme. So instead we would need to
2871 * replicate parts of the code in the above functions,
2872 * simplifying them because we wouldn't actually intend to
2873 * write out the pages, but rather only collect contiguous
2874 * logical block extents, call the multi-block allocator, and
2875 * then update the buffer heads with the block allocations.
2877 * For now, though, we'll cheat by calling filemap_flush(),
2878 * which will map the blocks, and start the I/O, but not
2879 * actually wait for the I/O to complete.
2881 return filemap_flush(inode
->i_mapping
);
2885 * bmap() is special. It gets used by applications such as lilo and by
2886 * the swapper to find the on-disk block of a specific piece of data.
2888 * Naturally, this is dangerous if the block concerned is still in the
2889 * journal. If somebody makes a swapfile on an ext4 data-journaling
2890 * filesystem and enables swap, then they may get a nasty shock when the
2891 * data getting swapped to that swapfile suddenly gets overwritten by
2892 * the original zero's written out previously to the journal and
2893 * awaiting writeback in the kernel's buffer cache.
2895 * So, if we see any bmap calls here on a modified, data-journaled file,
2896 * take extra steps to flush any blocks which might be in the cache.
2898 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2900 struct inode
*inode
= mapping
->host
;
2905 * We can get here for an inline file via the FIBMAP ioctl
2907 if (ext4_has_inline_data(inode
))
2910 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2911 test_opt(inode
->i_sb
, DELALLOC
)) {
2913 * With delalloc we want to sync the file
2914 * so that we can make sure we allocate
2917 filemap_write_and_wait(mapping
);
2920 if (EXT4_JOURNAL(inode
) &&
2921 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2923 * This is a REALLY heavyweight approach, but the use of
2924 * bmap on dirty files is expected to be extremely rare:
2925 * only if we run lilo or swapon on a freshly made file
2926 * do we expect this to happen.
2928 * (bmap requires CAP_SYS_RAWIO so this does not
2929 * represent an unprivileged user DOS attack --- we'd be
2930 * in trouble if mortal users could trigger this path at
2933 * NB. EXT4_STATE_JDATA is not set on files other than
2934 * regular files. If somebody wants to bmap a directory
2935 * or symlink and gets confused because the buffer
2936 * hasn't yet been flushed to disk, they deserve
2937 * everything they get.
2940 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2941 journal
= EXT4_JOURNAL(inode
);
2942 jbd2_journal_lock_updates(journal
);
2943 err
= jbd2_journal_flush(journal
);
2944 jbd2_journal_unlock_updates(journal
);
2950 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2953 static int ext4_readpage(struct file
*file
, struct page
*page
)
2956 struct inode
*inode
= page
->mapping
->host
;
2958 trace_ext4_readpage(page
);
2960 if (ext4_has_inline_data(inode
))
2961 ret
= ext4_readpage_inline(inode
, page
);
2964 return mpage_readpage(page
, ext4_get_block
);
2970 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2971 struct list_head
*pages
, unsigned nr_pages
)
2973 struct inode
*inode
= mapping
->host
;
2975 /* If the file has inline data, no need to do readpages. */
2976 if (ext4_has_inline_data(inode
))
2979 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
2982 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
2983 unsigned int length
)
2985 trace_ext4_invalidatepage(page
, offset
, length
);
2987 /* No journalling happens on data buffers when this function is used */
2988 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
2990 block_invalidatepage(page
, offset
, length
);
2993 static int __ext4_journalled_invalidatepage(struct page
*page
,
2994 unsigned int offset
,
2995 unsigned int length
)
2997 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2999 trace_ext4_journalled_invalidatepage(page
, offset
, length
);
3002 * If it's a full truncate we just forget about the pending dirtying
3004 if (offset
== 0 && length
== PAGE_CACHE_SIZE
)
3005 ClearPageChecked(page
);
3007 return jbd2_journal_invalidatepage(journal
, page
, offset
, length
);
3010 /* Wrapper for aops... */
3011 static void ext4_journalled_invalidatepage(struct page
*page
,
3012 unsigned int offset
,
3013 unsigned int length
)
3015 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
, length
) < 0);
3018 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
3020 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
3022 trace_ext4_releasepage(page
);
3024 /* Page has dirty journalled data -> cannot release */
3025 if (PageChecked(page
))
3028 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
3030 return try_to_free_buffers(page
);
3034 * ext4_get_block used when preparing for a DIO write or buffer write.
3035 * We allocate an uinitialized extent if blocks haven't been allocated.
3036 * The extent will be converted to initialized after the IO is complete.
3038 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
3039 struct buffer_head
*bh_result
, int create
)
3041 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
3042 inode
->i_ino
, create
);
3043 return _ext4_get_block(inode
, iblock
, bh_result
,
3044 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
3047 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
3048 struct buffer_head
*bh_result
, int create
)
3050 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
3051 inode
->i_ino
, create
);
3052 return _ext4_get_block(inode
, iblock
, bh_result
,
3053 EXT4_GET_BLOCKS_NO_LOCK
);
3056 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
3057 ssize_t size
, void *private)
3059 ext4_io_end_t
*io_end
= iocb
->private;
3061 /* if not async direct IO just return */
3065 ext_debug("ext4_end_io_dio(): io_end 0x%p "
3066 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
3067 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
3070 iocb
->private = NULL
;
3071 io_end
->offset
= offset
;
3072 io_end
->size
= size
;
3073 ext4_put_io_end(io_end
);
3077 * For ext4 extent files, ext4 will do direct-io write to holes,
3078 * preallocated extents, and those write extend the file, no need to
3079 * fall back to buffered IO.
3081 * For holes, we fallocate those blocks, mark them as unwritten
3082 * If those blocks were preallocated, we mark sure they are split, but
3083 * still keep the range to write as unwritten.
3085 * The unwritten extents will be converted to written when DIO is completed.
3086 * For async direct IO, since the IO may still pending when return, we
3087 * set up an end_io call back function, which will do the conversion
3088 * when async direct IO completed.
3090 * If the O_DIRECT write will extend the file then add this inode to the
3091 * orphan list. So recovery will truncate it back to the original size
3092 * if the machine crashes during the write.
3095 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
3096 struct iov_iter
*iter
, loff_t offset
)
3098 struct file
*file
= iocb
->ki_filp
;
3099 struct inode
*inode
= file
->f_mapping
->host
;
3101 size_t count
= iov_iter_count(iter
);
3103 get_block_t
*get_block_func
= NULL
;
3105 loff_t final_size
= offset
+ count
;
3106 ext4_io_end_t
*io_end
= NULL
;
3108 /* Use the old path for reads and writes beyond i_size. */
3109 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
3110 return ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
3112 BUG_ON(iocb
->private == NULL
);
3115 * Make all waiters for direct IO properly wait also for extent
3116 * conversion. This also disallows race between truncate() and
3117 * overwrite DIO as i_dio_count needs to be incremented under i_mutex.
3120 atomic_inc(&inode
->i_dio_count
);
3122 /* If we do a overwrite dio, i_mutex locking can be released */
3123 overwrite
= *((int *)iocb
->private);
3126 down_read(&EXT4_I(inode
)->i_data_sem
);
3127 mutex_unlock(&inode
->i_mutex
);
3131 * We could direct write to holes and fallocate.
3133 * Allocated blocks to fill the hole are marked as
3134 * unwritten to prevent parallel buffered read to expose
3135 * the stale data before DIO complete the data IO.
3137 * As to previously fallocated extents, ext4 get_block will
3138 * just simply mark the buffer mapped but still keep the
3139 * extents unwritten.
3141 * For non AIO case, we will convert those unwritten extents
3142 * to written after return back from blockdev_direct_IO.
3144 * For async DIO, the conversion needs to be deferred when the
3145 * IO is completed. The ext4 end_io callback function will be
3146 * called to take care of the conversion work. Here for async
3147 * case, we allocate an io_end structure to hook to the iocb.
3149 iocb
->private = NULL
;
3150 ext4_inode_aio_set(inode
, NULL
);
3151 if (!is_sync_kiocb(iocb
)) {
3152 io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3158 * Grab reference for DIO. Will be dropped in ext4_end_io_dio()
3160 iocb
->private = ext4_get_io_end(io_end
);
3162 * we save the io structure for current async direct
3163 * IO, so that later ext4_map_blocks() could flag the
3164 * io structure whether there is a unwritten extents
3165 * needs to be converted when IO is completed.
3167 ext4_inode_aio_set(inode
, io_end
);
3171 get_block_func
= ext4_get_block_write_nolock
;
3173 get_block_func
= ext4_get_block_write
;
3174 dio_flags
= DIO_LOCKING
;
3176 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3177 inode
->i_sb
->s_bdev
, iter
,
3185 * Put our reference to io_end. This can free the io_end structure e.g.
3186 * in sync IO case or in case of error. It can even perform extent
3187 * conversion if all bios we submitted finished before we got here.
3188 * Note that in that case iocb->private can be already set to NULL
3192 ext4_inode_aio_set(inode
, NULL
);
3193 ext4_put_io_end(io_end
);
3195 * When no IO was submitted ext4_end_io_dio() was not
3196 * called so we have to put iocb's reference.
3198 if (ret
<= 0 && ret
!= -EIOCBQUEUED
&& iocb
->private) {
3199 WARN_ON(iocb
->private != io_end
);
3200 WARN_ON(io_end
->flag
& EXT4_IO_END_UNWRITTEN
);
3201 ext4_put_io_end(io_end
);
3202 iocb
->private = NULL
;
3205 if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3206 EXT4_STATE_DIO_UNWRITTEN
)) {
3209 * for non AIO case, since the IO is already
3210 * completed, we could do the conversion right here
3212 err
= ext4_convert_unwritten_extents(NULL
, inode
,
3216 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3221 inode_dio_done(inode
);
3222 /* take i_mutex locking again if we do a ovewrite dio */
3224 up_read(&EXT4_I(inode
)->i_data_sem
);
3225 mutex_lock(&inode
->i_mutex
);
3231 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3232 struct iov_iter
*iter
, loff_t offset
)
3234 struct file
*file
= iocb
->ki_filp
;
3235 struct inode
*inode
= file
->f_mapping
->host
;
3236 size_t count
= iov_iter_count(iter
);
3240 * If we are doing data journalling we don't support O_DIRECT
3242 if (ext4_should_journal_data(inode
))
3245 /* Let buffer I/O handle the inline data case. */
3246 if (ext4_has_inline_data(inode
))
3249 trace_ext4_direct_IO_enter(inode
, offset
, count
, rw
);
3250 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3251 ret
= ext4_ext_direct_IO(rw
, iocb
, iter
, offset
);
3253 ret
= ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
3254 trace_ext4_direct_IO_exit(inode
, offset
, count
, rw
, ret
);
3259 * Pages can be marked dirty completely asynchronously from ext4's journalling
3260 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3261 * much here because ->set_page_dirty is called under VFS locks. The page is
3262 * not necessarily locked.
3264 * We cannot just dirty the page and leave attached buffers clean, because the
3265 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3266 * or jbddirty because all the journalling code will explode.
3268 * So what we do is to mark the page "pending dirty" and next time writepage
3269 * is called, propagate that into the buffers appropriately.
3271 static int ext4_journalled_set_page_dirty(struct page
*page
)
3273 SetPageChecked(page
);
3274 return __set_page_dirty_nobuffers(page
);
3277 static const struct address_space_operations ext4_aops
= {
3278 .readpage
= ext4_readpage
,
3279 .readpages
= ext4_readpages
,
3280 .writepage
= ext4_writepage
,
3281 .writepages
= ext4_writepages
,
3282 .write_begin
= ext4_write_begin
,
3283 .write_end
= ext4_write_end
,
3285 .invalidatepage
= ext4_invalidatepage
,
3286 .releasepage
= ext4_releasepage
,
3287 .direct_IO
= ext4_direct_IO
,
3288 .migratepage
= buffer_migrate_page
,
3289 .is_partially_uptodate
= block_is_partially_uptodate
,
3290 .error_remove_page
= generic_error_remove_page
,
3293 static const struct address_space_operations ext4_journalled_aops
= {
3294 .readpage
= ext4_readpage
,
3295 .readpages
= ext4_readpages
,
3296 .writepage
= ext4_writepage
,
3297 .writepages
= ext4_writepages
,
3298 .write_begin
= ext4_write_begin
,
3299 .write_end
= ext4_journalled_write_end
,
3300 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3302 .invalidatepage
= ext4_journalled_invalidatepage
,
3303 .releasepage
= ext4_releasepage
,
3304 .direct_IO
= ext4_direct_IO
,
3305 .is_partially_uptodate
= block_is_partially_uptodate
,
3306 .error_remove_page
= generic_error_remove_page
,
3309 static const struct address_space_operations ext4_da_aops
= {
3310 .readpage
= ext4_readpage
,
3311 .readpages
= ext4_readpages
,
3312 .writepage
= ext4_writepage
,
3313 .writepages
= ext4_writepages
,
3314 .write_begin
= ext4_da_write_begin
,
3315 .write_end
= ext4_da_write_end
,
3317 .invalidatepage
= ext4_da_invalidatepage
,
3318 .releasepage
= ext4_releasepage
,
3319 .direct_IO
= ext4_direct_IO
,
3320 .migratepage
= buffer_migrate_page
,
3321 .is_partially_uptodate
= block_is_partially_uptodate
,
3322 .error_remove_page
= generic_error_remove_page
,
3325 void ext4_set_aops(struct inode
*inode
)
3327 switch (ext4_inode_journal_mode(inode
)) {
3328 case EXT4_INODE_ORDERED_DATA_MODE
:
3329 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3331 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3332 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3334 case EXT4_INODE_JOURNAL_DATA_MODE
:
3335 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3340 if (test_opt(inode
->i_sb
, DELALLOC
))
3341 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3343 inode
->i_mapping
->a_ops
= &ext4_aops
;
3347 * ext4_block_zero_page_range() zeros out a mapping of length 'length'
3348 * starting from file offset 'from'. The range to be zero'd must
3349 * be contained with in one block. If the specified range exceeds
3350 * the end of the block it will be shortened to end of the block
3351 * that cooresponds to 'from'
3353 static int ext4_block_zero_page_range(handle_t
*handle
,
3354 struct address_space
*mapping
, loff_t from
, loff_t length
)
3356 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3357 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3358 unsigned blocksize
, max
, pos
;
3360 struct inode
*inode
= mapping
->host
;
3361 struct buffer_head
*bh
;
3365 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3366 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3370 blocksize
= inode
->i_sb
->s_blocksize
;
3371 max
= blocksize
- (offset
& (blocksize
- 1));
3374 * correct length if it does not fall between
3375 * 'from' and the end of the block
3377 if (length
> max
|| length
< 0)
3380 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3382 if (!page_has_buffers(page
))
3383 create_empty_buffers(page
, blocksize
, 0);
3385 /* Find the buffer that contains "offset" */
3386 bh
= page_buffers(page
);
3388 while (offset
>= pos
) {
3389 bh
= bh
->b_this_page
;
3393 if (buffer_freed(bh
)) {
3394 BUFFER_TRACE(bh
, "freed: skip");
3397 if (!buffer_mapped(bh
)) {
3398 BUFFER_TRACE(bh
, "unmapped");
3399 ext4_get_block(inode
, iblock
, bh
, 0);
3400 /* unmapped? It's a hole - nothing to do */
3401 if (!buffer_mapped(bh
)) {
3402 BUFFER_TRACE(bh
, "still unmapped");
3407 /* Ok, it's mapped. Make sure it's up-to-date */
3408 if (PageUptodate(page
))
3409 set_buffer_uptodate(bh
);
3411 if (!buffer_uptodate(bh
)) {
3413 ll_rw_block(READ
, 1, &bh
);
3415 /* Uhhuh. Read error. Complain and punt. */
3416 if (!buffer_uptodate(bh
))
3419 if (ext4_should_journal_data(inode
)) {
3420 BUFFER_TRACE(bh
, "get write access");
3421 err
= ext4_journal_get_write_access(handle
, bh
);
3425 zero_user(page
, offset
, length
);
3426 BUFFER_TRACE(bh
, "zeroed end of block");
3428 if (ext4_should_journal_data(inode
)) {
3429 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3432 mark_buffer_dirty(bh
);
3433 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
))
3434 err
= ext4_jbd2_file_inode(handle
, inode
);
3439 page_cache_release(page
);
3444 * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
3445 * up to the end of the block which corresponds to `from'.
3446 * This required during truncate. We need to physically zero the tail end
3447 * of that block so it doesn't yield old data if the file is later grown.
3449 static int ext4_block_truncate_page(handle_t
*handle
,
3450 struct address_space
*mapping
, loff_t from
)
3452 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3455 struct inode
*inode
= mapping
->host
;
3457 blocksize
= inode
->i_sb
->s_blocksize
;
3458 length
= blocksize
- (offset
& (blocksize
- 1));
3460 return ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3463 int ext4_zero_partial_blocks(handle_t
*handle
, struct inode
*inode
,
3464 loff_t lstart
, loff_t length
)
3466 struct super_block
*sb
= inode
->i_sb
;
3467 struct address_space
*mapping
= inode
->i_mapping
;
3468 unsigned partial_start
, partial_end
;
3469 ext4_fsblk_t start
, end
;
3470 loff_t byte_end
= (lstart
+ length
- 1);
3473 partial_start
= lstart
& (sb
->s_blocksize
- 1);
3474 partial_end
= byte_end
& (sb
->s_blocksize
- 1);
3476 start
= lstart
>> sb
->s_blocksize_bits
;
3477 end
= byte_end
>> sb
->s_blocksize_bits
;
3479 /* Handle partial zero within the single block */
3481 (partial_start
|| (partial_end
!= sb
->s_blocksize
- 1))) {
3482 err
= ext4_block_zero_page_range(handle
, mapping
,
3486 /* Handle partial zero out on the start of the range */
3487 if (partial_start
) {
3488 err
= ext4_block_zero_page_range(handle
, mapping
,
3489 lstart
, sb
->s_blocksize
);
3493 /* Handle partial zero out on the end of the range */
3494 if (partial_end
!= sb
->s_blocksize
- 1)
3495 err
= ext4_block_zero_page_range(handle
, mapping
,
3496 byte_end
- partial_end
,
3501 int ext4_can_truncate(struct inode
*inode
)
3503 if (S_ISREG(inode
->i_mode
))
3505 if (S_ISDIR(inode
->i_mode
))
3507 if (S_ISLNK(inode
->i_mode
))
3508 return !ext4_inode_is_fast_symlink(inode
);
3513 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3514 * associated with the given offset and length
3516 * @inode: File inode
3517 * @offset: The offset where the hole will begin
3518 * @len: The length of the hole
3520 * Returns: 0 on success or negative on failure
3523 int ext4_punch_hole(struct inode
*inode
, loff_t offset
, loff_t length
)
3525 struct super_block
*sb
= inode
->i_sb
;
3526 ext4_lblk_t first_block
, stop_block
;
3527 struct address_space
*mapping
= inode
->i_mapping
;
3528 loff_t first_block_offset
, last_block_offset
;
3530 unsigned int credits
;
3533 if (!S_ISREG(inode
->i_mode
))
3536 trace_ext4_punch_hole(inode
, offset
, length
, 0);
3539 * Write out all dirty pages to avoid race conditions
3540 * Then release them.
3542 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3543 ret
= filemap_write_and_wait_range(mapping
, offset
,
3544 offset
+ length
- 1);
3549 mutex_lock(&inode
->i_mutex
);
3551 /* No need to punch hole beyond i_size */
3552 if (offset
>= inode
->i_size
)
3556 * If the hole extends beyond i_size, set the hole
3557 * to end after the page that contains i_size
3559 if (offset
+ length
> inode
->i_size
) {
3560 length
= inode
->i_size
+
3561 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3565 if (offset
& (sb
->s_blocksize
- 1) ||
3566 (offset
+ length
) & (sb
->s_blocksize
- 1)) {
3568 * Attach jinode to inode for jbd2 if we do any zeroing of
3571 ret
= ext4_inode_attach_jinode(inode
);
3577 first_block_offset
= round_up(offset
, sb
->s_blocksize
);
3578 last_block_offset
= round_down((offset
+ length
), sb
->s_blocksize
) - 1;
3580 /* Now release the pages and zero block aligned part of pages*/
3581 if (last_block_offset
> first_block_offset
)
3582 truncate_pagecache_range(inode
, first_block_offset
,
3585 /* Wait all existing dio workers, newcomers will block on i_mutex */
3586 ext4_inode_block_unlocked_dio(inode
);
3587 inode_dio_wait(inode
);
3589 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3590 credits
= ext4_writepage_trans_blocks(inode
);
3592 credits
= ext4_blocks_for_truncate(inode
);
3593 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3594 if (IS_ERR(handle
)) {
3595 ret
= PTR_ERR(handle
);
3596 ext4_std_error(sb
, ret
);
3600 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
,
3605 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3606 EXT4_BLOCK_SIZE_BITS(sb
);
3607 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3609 /* If there are no blocks to remove, return now */
3610 if (first_block
>= stop_block
)
3613 down_write(&EXT4_I(inode
)->i_data_sem
);
3614 ext4_discard_preallocations(inode
);
3616 ret
= ext4_es_remove_extent(inode
, first_block
,
3617 stop_block
- first_block
);
3619 up_write(&EXT4_I(inode
)->i_data_sem
);
3623 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3624 ret
= ext4_ext_remove_space(inode
, first_block
,
3627 ret
= ext4_free_hole_blocks(handle
, inode
, first_block
,
3630 up_write(&EXT4_I(inode
)->i_data_sem
);
3632 ext4_handle_sync(handle
);
3634 /* Now release the pages again to reduce race window */
3635 if (last_block_offset
> first_block_offset
)
3636 truncate_pagecache_range(inode
, first_block_offset
,
3639 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3640 ext4_mark_inode_dirty(handle
, inode
);
3642 ext4_journal_stop(handle
);
3644 ext4_inode_resume_unlocked_dio(inode
);
3646 mutex_unlock(&inode
->i_mutex
);
3650 int ext4_inode_attach_jinode(struct inode
*inode
)
3652 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3653 struct jbd2_inode
*jinode
;
3655 if (ei
->jinode
|| !EXT4_SB(inode
->i_sb
)->s_journal
)
3658 jinode
= jbd2_alloc_inode(GFP_KERNEL
);
3659 spin_lock(&inode
->i_lock
);
3662 spin_unlock(&inode
->i_lock
);
3665 ei
->jinode
= jinode
;
3666 jbd2_journal_init_jbd_inode(ei
->jinode
, inode
);
3669 spin_unlock(&inode
->i_lock
);
3670 if (unlikely(jinode
!= NULL
))
3671 jbd2_free_inode(jinode
);
3678 * We block out ext4_get_block() block instantiations across the entire
3679 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3680 * simultaneously on behalf of the same inode.
3682 * As we work through the truncate and commit bits of it to the journal there
3683 * is one core, guiding principle: the file's tree must always be consistent on
3684 * disk. We must be able to restart the truncate after a crash.
3686 * The file's tree may be transiently inconsistent in memory (although it
3687 * probably isn't), but whenever we close off and commit a journal transaction,
3688 * the contents of (the filesystem + the journal) must be consistent and
3689 * restartable. It's pretty simple, really: bottom up, right to left (although
3690 * left-to-right works OK too).
3692 * Note that at recovery time, journal replay occurs *before* the restart of
3693 * truncate against the orphan inode list.
3695 * The committed inode has the new, desired i_size (which is the same as
3696 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3697 * that this inode's truncate did not complete and it will again call
3698 * ext4_truncate() to have another go. So there will be instantiated blocks
3699 * to the right of the truncation point in a crashed ext4 filesystem. But
3700 * that's fine - as long as they are linked from the inode, the post-crash
3701 * ext4_truncate() run will find them and release them.
3703 void ext4_truncate(struct inode
*inode
)
3705 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3706 unsigned int credits
;
3708 struct address_space
*mapping
= inode
->i_mapping
;
3711 * There is a possibility that we're either freeing the inode
3712 * or it's a completely new inode. In those cases we might not
3713 * have i_mutex locked because it's not necessary.
3715 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3716 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3717 trace_ext4_truncate_enter(inode
);
3719 if (!ext4_can_truncate(inode
))
3722 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3724 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3725 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3727 if (ext4_has_inline_data(inode
)) {
3730 ext4_inline_data_truncate(inode
, &has_inline
);
3735 /* If we zero-out tail of the page, we have to create jinode for jbd2 */
3736 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1)) {
3737 if (ext4_inode_attach_jinode(inode
) < 0)
3741 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3742 credits
= ext4_writepage_trans_blocks(inode
);
3744 credits
= ext4_blocks_for_truncate(inode
);
3746 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3747 if (IS_ERR(handle
)) {
3748 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3752 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1))
3753 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3756 * We add the inode to the orphan list, so that if this
3757 * truncate spans multiple transactions, and we crash, we will
3758 * resume the truncate when the filesystem recovers. It also
3759 * marks the inode dirty, to catch the new size.
3761 * Implication: the file must always be in a sane, consistent
3762 * truncatable state while each transaction commits.
3764 if (ext4_orphan_add(handle
, inode
))
3767 down_write(&EXT4_I(inode
)->i_data_sem
);
3769 ext4_discard_preallocations(inode
);
3771 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3772 ext4_ext_truncate(handle
, inode
);
3774 ext4_ind_truncate(handle
, inode
);
3776 up_write(&ei
->i_data_sem
);
3779 ext4_handle_sync(handle
);
3783 * If this was a simple ftruncate() and the file will remain alive,
3784 * then we need to clear up the orphan record which we created above.
3785 * However, if this was a real unlink then we were called by
3786 * ext4_delete_inode(), and we allow that function to clean up the
3787 * orphan info for us.
3790 ext4_orphan_del(handle
, inode
);
3792 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3793 ext4_mark_inode_dirty(handle
, inode
);
3794 ext4_journal_stop(handle
);
3796 trace_ext4_truncate_exit(inode
);
3800 * ext4_get_inode_loc returns with an extra refcount against the inode's
3801 * underlying buffer_head on success. If 'in_mem' is true, we have all
3802 * data in memory that is needed to recreate the on-disk version of this
3805 static int __ext4_get_inode_loc(struct inode
*inode
,
3806 struct ext4_iloc
*iloc
, int in_mem
)
3808 struct ext4_group_desc
*gdp
;
3809 struct buffer_head
*bh
;
3810 struct super_block
*sb
= inode
->i_sb
;
3812 int inodes_per_block
, inode_offset
;
3815 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3818 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3819 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3824 * Figure out the offset within the block group inode table
3826 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3827 inode_offset
= ((inode
->i_ino
- 1) %
3828 EXT4_INODES_PER_GROUP(sb
));
3829 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3830 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3832 bh
= sb_getblk(sb
, block
);
3835 if (!buffer_uptodate(bh
)) {
3839 * If the buffer has the write error flag, we have failed
3840 * to write out another inode in the same block. In this
3841 * case, we don't have to read the block because we may
3842 * read the old inode data successfully.
3844 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3845 set_buffer_uptodate(bh
);
3847 if (buffer_uptodate(bh
)) {
3848 /* someone brought it uptodate while we waited */
3854 * If we have all information of the inode in memory and this
3855 * is the only valid inode in the block, we need not read the
3859 struct buffer_head
*bitmap_bh
;
3862 start
= inode_offset
& ~(inodes_per_block
- 1);
3864 /* Is the inode bitmap in cache? */
3865 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3866 if (unlikely(!bitmap_bh
))
3870 * If the inode bitmap isn't in cache then the
3871 * optimisation may end up performing two reads instead
3872 * of one, so skip it.
3874 if (!buffer_uptodate(bitmap_bh
)) {
3878 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
3879 if (i
== inode_offset
)
3881 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
3885 if (i
== start
+ inodes_per_block
) {
3886 /* all other inodes are free, so skip I/O */
3887 memset(bh
->b_data
, 0, bh
->b_size
);
3888 set_buffer_uptodate(bh
);
3896 * If we need to do any I/O, try to pre-readahead extra
3897 * blocks from the inode table.
3899 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
3900 ext4_fsblk_t b
, end
, table
;
3902 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
3904 table
= ext4_inode_table(sb
, gdp
);
3905 /* s_inode_readahead_blks is always a power of 2 */
3906 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
3910 num
= EXT4_INODES_PER_GROUP(sb
);
3911 if (ext4_has_group_desc_csum(sb
))
3912 num
-= ext4_itable_unused_count(sb
, gdp
);
3913 table
+= num
/ inodes_per_block
;
3917 sb_breadahead(sb
, b
++);
3921 * There are other valid inodes in the buffer, this inode
3922 * has in-inode xattrs, or we don't have this inode in memory.
3923 * Read the block from disk.
3925 trace_ext4_load_inode(inode
);
3927 bh
->b_end_io
= end_buffer_read_sync
;
3928 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
3930 if (!buffer_uptodate(bh
)) {
3931 EXT4_ERROR_INODE_BLOCK(inode
, block
,
3932 "unable to read itable block");
3942 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
3944 /* We have all inode data except xattrs in memory here. */
3945 return __ext4_get_inode_loc(inode
, iloc
,
3946 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
3949 void ext4_set_inode_flags(struct inode
*inode
)
3951 unsigned int flags
= EXT4_I(inode
)->i_flags
;
3952 unsigned int new_fl
= 0;
3954 if (flags
& EXT4_SYNC_FL
)
3956 if (flags
& EXT4_APPEND_FL
)
3958 if (flags
& EXT4_IMMUTABLE_FL
)
3959 new_fl
|= S_IMMUTABLE
;
3960 if (flags
& EXT4_NOATIME_FL
)
3961 new_fl
|= S_NOATIME
;
3962 if (flags
& EXT4_DIRSYNC_FL
)
3963 new_fl
|= S_DIRSYNC
;
3964 inode_set_flags(inode
, new_fl
,
3965 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
);
3968 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
3969 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
3971 unsigned int vfs_fl
;
3972 unsigned long old_fl
, new_fl
;
3975 vfs_fl
= ei
->vfs_inode
.i_flags
;
3976 old_fl
= ei
->i_flags
;
3977 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
3978 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
3980 if (vfs_fl
& S_SYNC
)
3981 new_fl
|= EXT4_SYNC_FL
;
3982 if (vfs_fl
& S_APPEND
)
3983 new_fl
|= EXT4_APPEND_FL
;
3984 if (vfs_fl
& S_IMMUTABLE
)
3985 new_fl
|= EXT4_IMMUTABLE_FL
;
3986 if (vfs_fl
& S_NOATIME
)
3987 new_fl
|= EXT4_NOATIME_FL
;
3988 if (vfs_fl
& S_DIRSYNC
)
3989 new_fl
|= EXT4_DIRSYNC_FL
;
3990 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
3993 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
3994 struct ext4_inode_info
*ei
)
3997 struct inode
*inode
= &(ei
->vfs_inode
);
3998 struct super_block
*sb
= inode
->i_sb
;
4000 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4001 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
4002 /* we are using combined 48 bit field */
4003 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
4004 le32_to_cpu(raw_inode
->i_blocks_lo
);
4005 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
4006 /* i_blocks represent file system block size */
4007 return i_blocks
<< (inode
->i_blkbits
- 9);
4012 return le32_to_cpu(raw_inode
->i_blocks_lo
);
4016 static inline void ext4_iget_extra_inode(struct inode
*inode
,
4017 struct ext4_inode
*raw_inode
,
4018 struct ext4_inode_info
*ei
)
4020 __le32
*magic
= (void *)raw_inode
+
4021 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
4022 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4023 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
4024 ext4_find_inline_data_nolock(inode
);
4026 EXT4_I(inode
)->i_inline_off
= 0;
4029 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
4031 struct ext4_iloc iloc
;
4032 struct ext4_inode
*raw_inode
;
4033 struct ext4_inode_info
*ei
;
4034 struct inode
*inode
;
4035 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
4041 inode
= iget_locked(sb
, ino
);
4043 return ERR_PTR(-ENOMEM
);
4044 if (!(inode
->i_state
& I_NEW
))
4050 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4053 raw_inode
= ext4_raw_inode(&iloc
);
4055 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4056 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
4057 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
4058 EXT4_INODE_SIZE(inode
->i_sb
)) {
4059 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
4060 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
4061 EXT4_INODE_SIZE(inode
->i_sb
));
4066 ei
->i_extra_isize
= 0;
4068 /* Precompute checksum seed for inode metadata */
4069 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4070 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
)) {
4071 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4073 __le32 inum
= cpu_to_le32(inode
->i_ino
);
4074 __le32 gen
= raw_inode
->i_generation
;
4075 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
4077 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
4081 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
4082 EXT4_ERROR_INODE(inode
, "checksum invalid");
4087 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
4088 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
4089 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
4090 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4091 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
4092 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
4094 i_uid_write(inode
, i_uid
);
4095 i_gid_write(inode
, i_gid
);
4096 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
4098 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
4099 ei
->i_inline_off
= 0;
4100 ei
->i_dir_start_lookup
= 0;
4101 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
4102 /* We now have enough fields to check if the inode was active or not.
4103 * This is needed because nfsd might try to access dead inodes
4104 * the test is that same one that e2fsck uses
4105 * NeilBrown 1999oct15
4107 if (inode
->i_nlink
== 0) {
4108 if ((inode
->i_mode
== 0 ||
4109 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
4110 ino
!= EXT4_BOOT_LOADER_INO
) {
4111 /* this inode is deleted */
4115 /* The only unlinked inodes we let through here have
4116 * valid i_mode and are being read by the orphan
4117 * recovery code: that's fine, we're about to complete
4118 * the process of deleting those.
4119 * OR it is the EXT4_BOOT_LOADER_INO which is
4120 * not initialized on a new filesystem. */
4122 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
4123 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
4124 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
4125 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
4127 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
4128 inode
->i_size
= ext4_isize(raw_inode
);
4129 ei
->i_disksize
= inode
->i_size
;
4131 ei
->i_reserved_quota
= 0;
4133 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4134 ei
->i_block_group
= iloc
.block_group
;
4135 ei
->i_last_alloc_group
= ~0;
4137 * NOTE! The in-memory inode i_data array is in little-endian order
4138 * even on big-endian machines: we do NOT byteswap the block numbers!
4140 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4141 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4142 INIT_LIST_HEAD(&ei
->i_orphan
);
4145 * Set transaction id's of transactions that have to be committed
4146 * to finish f[data]sync. We set them to currently running transaction
4147 * as we cannot be sure that the inode or some of its metadata isn't
4148 * part of the transaction - the inode could have been reclaimed and
4149 * now it is reread from disk.
4152 transaction_t
*transaction
;
4155 read_lock(&journal
->j_state_lock
);
4156 if (journal
->j_running_transaction
)
4157 transaction
= journal
->j_running_transaction
;
4159 transaction
= journal
->j_committing_transaction
;
4161 tid
= transaction
->t_tid
;
4163 tid
= journal
->j_commit_sequence
;
4164 read_unlock(&journal
->j_state_lock
);
4165 ei
->i_sync_tid
= tid
;
4166 ei
->i_datasync_tid
= tid
;
4169 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4170 if (ei
->i_extra_isize
== 0) {
4171 /* The extra space is currently unused. Use it. */
4172 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4173 EXT4_GOOD_OLD_INODE_SIZE
;
4175 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4179 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4180 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4181 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4182 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4184 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4185 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4186 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4187 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4189 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4194 if (ei
->i_file_acl
&&
4195 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4196 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4200 } else if (!ext4_has_inline_data(inode
)) {
4201 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4202 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4203 (S_ISLNK(inode
->i_mode
) &&
4204 !ext4_inode_is_fast_symlink(inode
))))
4205 /* Validate extent which is part of inode */
4206 ret
= ext4_ext_check_inode(inode
);
4207 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4208 (S_ISLNK(inode
->i_mode
) &&
4209 !ext4_inode_is_fast_symlink(inode
))) {
4210 /* Validate block references which are part of inode */
4211 ret
= ext4_ind_check_inode(inode
);
4217 if (S_ISREG(inode
->i_mode
)) {
4218 inode
->i_op
= &ext4_file_inode_operations
;
4219 inode
->i_fop
= &ext4_file_operations
;
4220 ext4_set_aops(inode
);
4221 } else if (S_ISDIR(inode
->i_mode
)) {
4222 inode
->i_op
= &ext4_dir_inode_operations
;
4223 inode
->i_fop
= &ext4_dir_operations
;
4224 } else if (S_ISLNK(inode
->i_mode
)) {
4225 if (ext4_inode_is_fast_symlink(inode
)) {
4226 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4227 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4228 sizeof(ei
->i_data
) - 1);
4230 inode
->i_op
= &ext4_symlink_inode_operations
;
4231 ext4_set_aops(inode
);
4233 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4234 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4235 inode
->i_op
= &ext4_special_inode_operations
;
4236 if (raw_inode
->i_block
[0])
4237 init_special_inode(inode
, inode
->i_mode
,
4238 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4240 init_special_inode(inode
, inode
->i_mode
,
4241 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4242 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4243 make_bad_inode(inode
);
4246 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4250 ext4_set_inode_flags(inode
);
4251 unlock_new_inode(inode
);
4257 return ERR_PTR(ret
);
4260 static int ext4_inode_blocks_set(handle_t
*handle
,
4261 struct ext4_inode
*raw_inode
,
4262 struct ext4_inode_info
*ei
)
4264 struct inode
*inode
= &(ei
->vfs_inode
);
4265 u64 i_blocks
= inode
->i_blocks
;
4266 struct super_block
*sb
= inode
->i_sb
;
4268 if (i_blocks
<= ~0U) {
4270 * i_blocks can be represented in a 32 bit variable
4271 * as multiple of 512 bytes
4273 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4274 raw_inode
->i_blocks_high
= 0;
4275 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4278 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4281 if (i_blocks
<= 0xffffffffffffULL
) {
4283 * i_blocks can be represented in a 48 bit variable
4284 * as multiple of 512 bytes
4286 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4287 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4288 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4290 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4291 /* i_block is stored in file system block size */
4292 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4293 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4294 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4300 * Post the struct inode info into an on-disk inode location in the
4301 * buffer-cache. This gobbles the caller's reference to the
4302 * buffer_head in the inode location struct.
4304 * The caller must have write access to iloc->bh.
4306 static int ext4_do_update_inode(handle_t
*handle
,
4307 struct inode
*inode
,
4308 struct ext4_iloc
*iloc
)
4310 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4311 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4312 struct buffer_head
*bh
= iloc
->bh
;
4313 struct super_block
*sb
= inode
->i_sb
;
4314 int err
= 0, rc
, block
;
4315 int need_datasync
= 0, set_large_file
= 0;
4319 spin_lock(&ei
->i_raw_lock
);
4321 /* For fields not tracked in the in-memory inode,
4322 * initialise them to zero for new inodes. */
4323 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4324 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4326 ext4_get_inode_flags(ei
);
4327 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4328 i_uid
= i_uid_read(inode
);
4329 i_gid
= i_gid_read(inode
);
4330 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4331 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4332 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4334 * Fix up interoperability with old kernels. Otherwise, old inodes get
4335 * re-used with the upper 16 bits of the uid/gid intact
4338 raw_inode
->i_uid_high
=
4339 cpu_to_le16(high_16_bits(i_uid
));
4340 raw_inode
->i_gid_high
=
4341 cpu_to_le16(high_16_bits(i_gid
));
4343 raw_inode
->i_uid_high
= 0;
4344 raw_inode
->i_gid_high
= 0;
4347 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4348 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4349 raw_inode
->i_uid_high
= 0;
4350 raw_inode
->i_gid_high
= 0;
4352 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4354 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4355 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4356 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4357 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4359 if (ext4_inode_blocks_set(handle
, raw_inode
, ei
)) {
4360 spin_unlock(&ei
->i_raw_lock
);
4363 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4364 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4365 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
)))
4366 raw_inode
->i_file_acl_high
=
4367 cpu_to_le16(ei
->i_file_acl
>> 32);
4368 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4369 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4370 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4373 if (ei
->i_disksize
> 0x7fffffffULL
) {
4374 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4375 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4376 EXT4_SB(sb
)->s_es
->s_rev_level
==
4377 cpu_to_le32(EXT4_GOOD_OLD_REV
))
4380 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4381 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4382 if (old_valid_dev(inode
->i_rdev
)) {
4383 raw_inode
->i_block
[0] =
4384 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4385 raw_inode
->i_block
[1] = 0;
4387 raw_inode
->i_block
[0] = 0;
4388 raw_inode
->i_block
[1] =
4389 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4390 raw_inode
->i_block
[2] = 0;
4392 } else if (!ext4_has_inline_data(inode
)) {
4393 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4394 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4397 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4398 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4399 if (ei
->i_extra_isize
) {
4400 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4401 raw_inode
->i_version_hi
=
4402 cpu_to_le32(inode
->i_version
>> 32);
4403 raw_inode
->i_extra_isize
=
4404 cpu_to_le16(ei
->i_extra_isize
);
4408 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4410 spin_unlock(&ei
->i_raw_lock
);
4412 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4413 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4416 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4417 if (set_large_file
) {
4418 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get write access");
4419 err
= ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
);
4422 ext4_update_dynamic_rev(sb
);
4423 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4424 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4425 ext4_handle_sync(handle
);
4426 err
= ext4_handle_dirty_super(handle
, sb
);
4428 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4431 ext4_std_error(inode
->i_sb
, err
);
4436 * ext4_write_inode()
4438 * We are called from a few places:
4440 * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files.
4441 * Here, there will be no transaction running. We wait for any running
4442 * transaction to commit.
4444 * - Within flush work (sys_sync(), kupdate and such).
4445 * We wait on commit, if told to.
4447 * - Within iput_final() -> write_inode_now()
4448 * We wait on commit, if told to.
4450 * In all cases it is actually safe for us to return without doing anything,
4451 * because the inode has been copied into a raw inode buffer in
4452 * ext4_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL
4455 * Note that we are absolutely dependent upon all inode dirtiers doing the
4456 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4457 * which we are interested.
4459 * It would be a bug for them to not do this. The code:
4461 * mark_inode_dirty(inode)
4463 * inode->i_size = expr;
4465 * is in error because write_inode() could occur while `stuff()' is running,
4466 * and the new i_size will be lost. Plus the inode will no longer be on the
4467 * superblock's dirty inode list.
4469 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4473 if (WARN_ON_ONCE(current
->flags
& PF_MEMALLOC
))
4476 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4477 if (ext4_journal_current_handle()) {
4478 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4484 * No need to force transaction in WB_SYNC_NONE mode. Also
4485 * ext4_sync_fs() will force the commit after everything is
4488 if (wbc
->sync_mode
!= WB_SYNC_ALL
|| wbc
->for_sync
)
4491 err
= ext4_force_commit(inode
->i_sb
);
4493 struct ext4_iloc iloc
;
4495 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4499 * sync(2) will flush the whole buffer cache. No need to do
4500 * it here separately for each inode.
4502 if (wbc
->sync_mode
== WB_SYNC_ALL
&& !wbc
->for_sync
)
4503 sync_dirty_buffer(iloc
.bh
);
4504 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4505 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4506 "IO error syncing inode");
4515 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4516 * buffers that are attached to a page stradding i_size and are undergoing
4517 * commit. In that case we have to wait for commit to finish and try again.
4519 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4523 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4524 tid_t commit_tid
= 0;
4527 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4529 * All buffers in the last page remain valid? Then there's nothing to
4530 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4533 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4536 page
= find_lock_page(inode
->i_mapping
,
4537 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4540 ret
= __ext4_journalled_invalidatepage(page
, offset
,
4541 PAGE_CACHE_SIZE
- offset
);
4543 page_cache_release(page
);
4547 read_lock(&journal
->j_state_lock
);
4548 if (journal
->j_committing_transaction
)
4549 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4550 read_unlock(&journal
->j_state_lock
);
4552 jbd2_log_wait_commit(journal
, commit_tid
);
4559 * Called from notify_change.
4561 * We want to trap VFS attempts to truncate the file as soon as
4562 * possible. In particular, we want to make sure that when the VFS
4563 * shrinks i_size, we put the inode on the orphan list and modify
4564 * i_disksize immediately, so that during the subsequent flushing of
4565 * dirty pages and freeing of disk blocks, we can guarantee that any
4566 * commit will leave the blocks being flushed in an unused state on
4567 * disk. (On recovery, the inode will get truncated and the blocks will
4568 * be freed, so we have a strong guarantee that no future commit will
4569 * leave these blocks visible to the user.)
4571 * Another thing we have to assure is that if we are in ordered mode
4572 * and inode is still attached to the committing transaction, we must
4573 * we start writeout of all the dirty pages which are being truncated.
4574 * This way we are sure that all the data written in the previous
4575 * transaction are already on disk (truncate waits for pages under
4578 * Called with inode->i_mutex down.
4580 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4582 struct inode
*inode
= dentry
->d_inode
;
4585 const unsigned int ia_valid
= attr
->ia_valid
;
4587 error
= inode_change_ok(inode
, attr
);
4591 if (is_quota_modification(inode
, attr
))
4592 dquot_initialize(inode
);
4593 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4594 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4597 /* (user+group)*(old+new) structure, inode write (sb,
4598 * inode block, ? - but truncate inode update has it) */
4599 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4600 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4601 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4602 if (IS_ERR(handle
)) {
4603 error
= PTR_ERR(handle
);
4606 error
= dquot_transfer(inode
, attr
);
4608 ext4_journal_stop(handle
);
4611 /* Update corresponding info in inode so that everything is in
4612 * one transaction */
4613 if (attr
->ia_valid
& ATTR_UID
)
4614 inode
->i_uid
= attr
->ia_uid
;
4615 if (attr
->ia_valid
& ATTR_GID
)
4616 inode
->i_gid
= attr
->ia_gid
;
4617 error
= ext4_mark_inode_dirty(handle
, inode
);
4618 ext4_journal_stop(handle
);
4621 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4624 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4625 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4627 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4631 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4632 inode_inc_iversion(inode
);
4634 if (S_ISREG(inode
->i_mode
) &&
4635 (attr
->ia_size
< inode
->i_size
)) {
4636 if (ext4_should_order_data(inode
)) {
4637 error
= ext4_begin_ordered_truncate(inode
,
4642 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4643 if (IS_ERR(handle
)) {
4644 error
= PTR_ERR(handle
);
4647 if (ext4_handle_valid(handle
)) {
4648 error
= ext4_orphan_add(handle
, inode
);
4651 down_write(&EXT4_I(inode
)->i_data_sem
);
4652 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4653 rc
= ext4_mark_inode_dirty(handle
, inode
);
4657 * We have to update i_size under i_data_sem together
4658 * with i_disksize to avoid races with writeback code
4659 * running ext4_wb_update_i_disksize().
4662 i_size_write(inode
, attr
->ia_size
);
4663 up_write(&EXT4_I(inode
)->i_data_sem
);
4664 ext4_journal_stop(handle
);
4666 ext4_orphan_del(NULL
, inode
);
4670 i_size_write(inode
, attr
->ia_size
);
4673 * Blocks are going to be removed from the inode. Wait
4674 * for dio in flight. Temporarily disable
4675 * dioread_nolock to prevent livelock.
4678 if (!ext4_should_journal_data(inode
)) {
4679 ext4_inode_block_unlocked_dio(inode
);
4680 inode_dio_wait(inode
);
4681 ext4_inode_resume_unlocked_dio(inode
);
4683 ext4_wait_for_tail_page_commit(inode
);
4686 * Truncate pagecache after we've waited for commit
4687 * in data=journal mode to make pages freeable.
4689 truncate_pagecache(inode
, inode
->i_size
);
4692 * We want to call ext4_truncate() even if attr->ia_size ==
4693 * inode->i_size for cases like truncation of fallocated space
4695 if (attr
->ia_valid
& ATTR_SIZE
)
4696 ext4_truncate(inode
);
4699 setattr_copy(inode
, attr
);
4700 mark_inode_dirty(inode
);
4704 * If the call to ext4_truncate failed to get a transaction handle at
4705 * all, we need to clean up the in-core orphan list manually.
4707 if (orphan
&& inode
->i_nlink
)
4708 ext4_orphan_del(NULL
, inode
);
4710 if (!rc
&& (ia_valid
& ATTR_MODE
))
4711 rc
= posix_acl_chmod(inode
, inode
->i_mode
);
4714 ext4_std_error(inode
->i_sb
, error
);
4720 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4723 struct inode
*inode
;
4724 unsigned long long delalloc_blocks
;
4726 inode
= dentry
->d_inode
;
4727 generic_fillattr(inode
, stat
);
4730 * If there is inline data in the inode, the inode will normally not
4731 * have data blocks allocated (it may have an external xattr block).
4732 * Report at least one sector for such files, so tools like tar, rsync,
4733 * others doen't incorrectly think the file is completely sparse.
4735 if (unlikely(ext4_has_inline_data(inode
)))
4736 stat
->blocks
+= (stat
->size
+ 511) >> 9;
4739 * We can't update i_blocks if the block allocation is delayed
4740 * otherwise in the case of system crash before the real block
4741 * allocation is done, we will have i_blocks inconsistent with
4742 * on-disk file blocks.
4743 * We always keep i_blocks updated together with real
4744 * allocation. But to not confuse with user, stat
4745 * will return the blocks that include the delayed allocation
4746 * blocks for this file.
4748 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4749 EXT4_I(inode
)->i_reserved_data_blocks
);
4750 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
- 9);
4754 static int ext4_index_trans_blocks(struct inode
*inode
, int lblocks
,
4757 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4758 return ext4_ind_trans_blocks(inode
, lblocks
);
4759 return ext4_ext_index_trans_blocks(inode
, pextents
);
4763 * Account for index blocks, block groups bitmaps and block group
4764 * descriptor blocks if modify datablocks and index blocks
4765 * worse case, the indexs blocks spread over different block groups
4767 * If datablocks are discontiguous, they are possible to spread over
4768 * different block groups too. If they are contiguous, with flexbg,
4769 * they could still across block group boundary.
4771 * Also account for superblock, inode, quota and xattr blocks
4773 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
4776 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4782 * How many index blocks need to touch to map @lblocks logical blocks
4783 * to @pextents physical extents?
4785 idxblocks
= ext4_index_trans_blocks(inode
, lblocks
, pextents
);
4790 * Now let's see how many group bitmaps and group descriptors need
4793 groups
= idxblocks
+ pextents
;
4795 if (groups
> ngroups
)
4797 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4798 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4800 /* bitmaps and block group descriptor blocks */
4801 ret
+= groups
+ gdpblocks
;
4803 /* Blocks for super block, inode, quota and xattr blocks */
4804 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4810 * Calculate the total number of credits to reserve to fit
4811 * the modification of a single pages into a single transaction,
4812 * which may include multiple chunks of block allocations.
4814 * This could be called via ext4_write_begin()
4816 * We need to consider the worse case, when
4817 * one new block per extent.
4819 int ext4_writepage_trans_blocks(struct inode
*inode
)
4821 int bpp
= ext4_journal_blocks_per_page(inode
);
4824 ret
= ext4_meta_trans_blocks(inode
, bpp
, bpp
);
4826 /* Account for data blocks for journalled mode */
4827 if (ext4_should_journal_data(inode
))
4833 * Calculate the journal credits for a chunk of data modification.
4835 * This is called from DIO, fallocate or whoever calling
4836 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4838 * journal buffers for data blocks are not included here, as DIO
4839 * and fallocate do no need to journal data buffers.
4841 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4843 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4847 * The caller must have previously called ext4_reserve_inode_write().
4848 * Give this, we know that the caller already has write access to iloc->bh.
4850 int ext4_mark_iloc_dirty(handle_t
*handle
,
4851 struct inode
*inode
, struct ext4_iloc
*iloc
)
4855 if (IS_I_VERSION(inode
))
4856 inode_inc_iversion(inode
);
4858 /* the do_update_inode consumes one bh->b_count */
4861 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4862 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4868 * On success, We end up with an outstanding reference count against
4869 * iloc->bh. This _must_ be cleaned up later.
4873 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4874 struct ext4_iloc
*iloc
)
4878 err
= ext4_get_inode_loc(inode
, iloc
);
4880 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4881 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4887 ext4_std_error(inode
->i_sb
, err
);
4892 * Expand an inode by new_extra_isize bytes.
4893 * Returns 0 on success or negative error number on failure.
4895 static int ext4_expand_extra_isize(struct inode
*inode
,
4896 unsigned int new_extra_isize
,
4897 struct ext4_iloc iloc
,
4900 struct ext4_inode
*raw_inode
;
4901 struct ext4_xattr_ibody_header
*header
;
4903 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
4906 raw_inode
= ext4_raw_inode(&iloc
);
4908 header
= IHDR(inode
, raw_inode
);
4910 /* No extended attributes present */
4911 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
4912 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4913 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
4915 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
4919 /* try to expand with EAs present */
4920 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
4925 * What we do here is to mark the in-core inode as clean with respect to inode
4926 * dirtiness (it may still be data-dirty).
4927 * This means that the in-core inode may be reaped by prune_icache
4928 * without having to perform any I/O. This is a very good thing,
4929 * because *any* task may call prune_icache - even ones which
4930 * have a transaction open against a different journal.
4932 * Is this cheating? Not really. Sure, we haven't written the
4933 * inode out, but prune_icache isn't a user-visible syncing function.
4934 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
4935 * we start and wait on commits.
4937 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
4939 struct ext4_iloc iloc
;
4940 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4941 static unsigned int mnt_count
;
4945 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
4946 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
4947 if (ext4_handle_valid(handle
) &&
4948 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
4949 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
4951 * We need extra buffer credits since we may write into EA block
4952 * with this same handle. If journal_extend fails, then it will
4953 * only result in a minor loss of functionality for that inode.
4954 * If this is felt to be critical, then e2fsck should be run to
4955 * force a large enough s_min_extra_isize.
4957 if ((jbd2_journal_extend(handle
,
4958 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
4959 ret
= ext4_expand_extra_isize(inode
,
4960 sbi
->s_want_extra_isize
,
4963 ext4_set_inode_state(inode
,
4964 EXT4_STATE_NO_EXPAND
);
4966 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
4967 ext4_warning(inode
->i_sb
,
4968 "Unable to expand inode %lu. Delete"
4969 " some EAs or run e2fsck.",
4972 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
4978 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
4983 * ext4_dirty_inode() is called from __mark_inode_dirty()
4985 * We're really interested in the case where a file is being extended.
4986 * i_size has been changed by generic_commit_write() and we thus need
4987 * to include the updated inode in the current transaction.
4989 * Also, dquot_alloc_block() will always dirty the inode when blocks
4990 * are allocated to the file.
4992 * If the inode is marked synchronous, we don't honour that here - doing
4993 * so would cause a commit on atime updates, which we don't bother doing.
4994 * We handle synchronous inodes at the highest possible level.
4996 void ext4_dirty_inode(struct inode
*inode
, int flags
)
5000 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
5004 ext4_mark_inode_dirty(handle
, inode
);
5006 ext4_journal_stop(handle
);
5013 * Bind an inode's backing buffer_head into this transaction, to prevent
5014 * it from being flushed to disk early. Unlike
5015 * ext4_reserve_inode_write, this leaves behind no bh reference and
5016 * returns no iloc structure, so the caller needs to repeat the iloc
5017 * lookup to mark the inode dirty later.
5019 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
5021 struct ext4_iloc iloc
;
5025 err
= ext4_get_inode_loc(inode
, &iloc
);
5027 BUFFER_TRACE(iloc
.bh
, "get_write_access");
5028 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
5030 err
= ext4_handle_dirty_metadata(handle
,
5036 ext4_std_error(inode
->i_sb
, err
);
5041 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
5048 * We have to be very careful here: changing a data block's
5049 * journaling status dynamically is dangerous. If we write a
5050 * data block to the journal, change the status and then delete
5051 * that block, we risk forgetting to revoke the old log record
5052 * from the journal and so a subsequent replay can corrupt data.
5053 * So, first we make sure that the journal is empty and that
5054 * nobody is changing anything.
5057 journal
= EXT4_JOURNAL(inode
);
5060 if (is_journal_aborted(journal
))
5062 /* We have to allocate physical blocks for delalloc blocks
5063 * before flushing journal. otherwise delalloc blocks can not
5064 * be allocated any more. even more truncate on delalloc blocks
5065 * could trigger BUG by flushing delalloc blocks in journal.
5066 * There is no delalloc block in non-journal data mode.
5068 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5069 err
= ext4_alloc_da_blocks(inode
);
5074 /* Wait for all existing dio workers */
5075 ext4_inode_block_unlocked_dio(inode
);
5076 inode_dio_wait(inode
);
5078 jbd2_journal_lock_updates(journal
);
5081 * OK, there are no updates running now, and all cached data is
5082 * synced to disk. We are now in a completely consistent state
5083 * which doesn't have anything in the journal, and we know that
5084 * no filesystem updates are running, so it is safe to modify
5085 * the inode's in-core data-journaling state flag now.
5089 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5091 jbd2_journal_flush(journal
);
5092 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5094 ext4_set_aops(inode
);
5096 jbd2_journal_unlock_updates(journal
);
5097 ext4_inode_resume_unlocked_dio(inode
);
5099 /* Finally we can mark the inode as dirty. */
5101 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5103 return PTR_ERR(handle
);
5105 err
= ext4_mark_inode_dirty(handle
, inode
);
5106 ext4_handle_sync(handle
);
5107 ext4_journal_stop(handle
);
5108 ext4_std_error(inode
->i_sb
, err
);
5113 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5115 return !buffer_mapped(bh
);
5118 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5120 struct page
*page
= vmf
->page
;
5124 struct file
*file
= vma
->vm_file
;
5125 struct inode
*inode
= file_inode(file
);
5126 struct address_space
*mapping
= inode
->i_mapping
;
5128 get_block_t
*get_block
;
5131 sb_start_pagefault(inode
->i_sb
);
5132 file_update_time(vma
->vm_file
);
5133 /* Delalloc case is easy... */
5134 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5135 !ext4_should_journal_data(inode
) &&
5136 !ext4_nonda_switch(inode
->i_sb
)) {
5138 ret
= __block_page_mkwrite(vma
, vmf
,
5139 ext4_da_get_block_prep
);
5140 } while (ret
== -ENOSPC
&&
5141 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5146 size
= i_size_read(inode
);
5147 /* Page got truncated from under us? */
5148 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5150 ret
= VM_FAULT_NOPAGE
;
5154 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5155 len
= size
& ~PAGE_CACHE_MASK
;
5157 len
= PAGE_CACHE_SIZE
;
5159 * Return if we have all the buffers mapped. This avoids the need to do
5160 * journal_start/journal_stop which can block and take a long time
5162 if (page_has_buffers(page
)) {
5163 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5165 ext4_bh_unmapped
)) {
5166 /* Wait so that we don't change page under IO */
5167 wait_for_stable_page(page
);
5168 ret
= VM_FAULT_LOCKED
;
5173 /* OK, we need to fill the hole... */
5174 if (ext4_should_dioread_nolock(inode
))
5175 get_block
= ext4_get_block_write
;
5177 get_block
= ext4_get_block
;
5179 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5180 ext4_writepage_trans_blocks(inode
));
5181 if (IS_ERR(handle
)) {
5182 ret
= VM_FAULT_SIGBUS
;
5185 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5186 if (!ret
&& ext4_should_journal_data(inode
)) {
5187 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5188 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5190 ret
= VM_FAULT_SIGBUS
;
5191 ext4_journal_stop(handle
);
5194 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5196 ext4_journal_stop(handle
);
5197 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5200 ret
= block_page_mkwrite_return(ret
);
5202 sb_end_pagefault(inode
->i_sb
);