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/bitops.h>
42 #include "ext4_jbd2.h"
47 #include <trace/events/ext4.h>
49 #define MPAGE_DA_EXTENT_TAIL 0x01
51 static __u32
ext4_inode_csum(struct inode
*inode
, struct ext4_inode
*raw
,
52 struct ext4_inode_info
*ei
)
54 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
59 csum_lo
= le16_to_cpu(raw
->i_checksum_lo
);
60 raw
->i_checksum_lo
= 0;
61 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
62 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
)) {
63 csum_hi
= le16_to_cpu(raw
->i_checksum_hi
);
64 raw
->i_checksum_hi
= 0;
67 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)raw
,
68 EXT4_INODE_SIZE(inode
->i_sb
));
70 raw
->i_checksum_lo
= cpu_to_le16(csum_lo
);
71 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
72 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
73 raw
->i_checksum_hi
= cpu_to_le16(csum_hi
);
78 static int ext4_inode_csum_verify(struct inode
*inode
, struct ext4_inode
*raw
,
79 struct ext4_inode_info
*ei
)
81 __u32 provided
, calculated
;
83 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
84 cpu_to_le32(EXT4_OS_LINUX
) ||
85 !ext4_has_metadata_csum(inode
->i_sb
))
88 provided
= le16_to_cpu(raw
->i_checksum_lo
);
89 calculated
= ext4_inode_csum(inode
, raw
, ei
);
90 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
91 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
92 provided
|= ((__u32
)le16_to_cpu(raw
->i_checksum_hi
)) << 16;
96 return provided
== calculated
;
99 static void ext4_inode_csum_set(struct inode
*inode
, struct ext4_inode
*raw
,
100 struct ext4_inode_info
*ei
)
104 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
105 cpu_to_le32(EXT4_OS_LINUX
) ||
106 !ext4_has_metadata_csum(inode
->i_sb
))
109 csum
= ext4_inode_csum(inode
, raw
, ei
);
110 raw
->i_checksum_lo
= cpu_to_le16(csum
& 0xFFFF);
111 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
112 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
113 raw
->i_checksum_hi
= cpu_to_le16(csum
>> 16);
116 static inline int ext4_begin_ordered_truncate(struct inode
*inode
,
119 trace_ext4_begin_ordered_truncate(inode
, new_size
);
121 * If jinode is zero, then we never opened the file for
122 * writing, so there's no need to call
123 * jbd2_journal_begin_ordered_truncate() since there's no
124 * outstanding writes we need to flush.
126 if (!EXT4_I(inode
)->jinode
)
128 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode
),
129 EXT4_I(inode
)->jinode
,
133 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
134 unsigned int length
);
135 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
136 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
137 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
141 * Test whether an inode is a fast symlink.
143 static int ext4_inode_is_fast_symlink(struct inode
*inode
)
145 int ea_blocks
= EXT4_I(inode
)->i_file_acl
?
146 EXT4_CLUSTER_SIZE(inode
->i_sb
) >> 9 : 0;
148 if (ext4_has_inline_data(inode
))
151 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
155 * Restart the transaction associated with *handle. This does a commit,
156 * so before we call here everything must be consistently dirtied against
159 int ext4_truncate_restart_trans(handle_t
*handle
, struct inode
*inode
,
165 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
166 * moment, get_block can be called only for blocks inside i_size since
167 * page cache has been already dropped and writes are blocked by
168 * i_mutex. So we can safely drop the i_data_sem here.
170 BUG_ON(EXT4_JOURNAL(inode
) == NULL
);
171 jbd_debug(2, "restarting handle %p\n", handle
);
172 up_write(&EXT4_I(inode
)->i_data_sem
);
173 ret
= ext4_journal_restart(handle
, nblocks
);
174 down_write(&EXT4_I(inode
)->i_data_sem
);
175 ext4_discard_preallocations(inode
);
181 * Called at the last iput() if i_nlink is zero.
183 void ext4_evict_inode(struct inode
*inode
)
188 trace_ext4_evict_inode(inode
);
190 if (inode
->i_nlink
) {
192 * When journalling data dirty buffers are tracked only in the
193 * journal. So although mm thinks everything is clean and
194 * ready for reaping the inode might still have some pages to
195 * write in the running transaction or waiting to be
196 * checkpointed. Thus calling jbd2_journal_invalidatepage()
197 * (via truncate_inode_pages()) to discard these buffers can
198 * cause data loss. Also even if we did not discard these
199 * buffers, we would have no way to find them after the inode
200 * is reaped and thus user could see stale data if he tries to
201 * read them before the transaction is checkpointed. So be
202 * careful and force everything to disk here... We use
203 * ei->i_datasync_tid to store the newest transaction
204 * containing inode's data.
206 * Note that directories do not have this problem because they
207 * don't use page cache.
209 if (ext4_should_journal_data(inode
) &&
210 (S_ISLNK(inode
->i_mode
) || S_ISREG(inode
->i_mode
)) &&
211 inode
->i_ino
!= EXT4_JOURNAL_INO
) {
212 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
213 tid_t commit_tid
= EXT4_I(inode
)->i_datasync_tid
;
215 jbd2_complete_transaction(journal
, commit_tid
);
216 filemap_write_and_wait(&inode
->i_data
);
218 truncate_inode_pages_final(&inode
->i_data
);
220 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
224 if (is_bad_inode(inode
))
226 dquot_initialize(inode
);
228 if (ext4_should_order_data(inode
))
229 ext4_begin_ordered_truncate(inode
, 0);
230 truncate_inode_pages_final(&inode
->i_data
);
232 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
235 * Protect us against freezing - iput() caller didn't have to have any
236 * protection against it
238 sb_start_intwrite(inode
->i_sb
);
239 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
,
240 ext4_blocks_for_truncate(inode
)+3);
241 if (IS_ERR(handle
)) {
242 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
244 * If we're going to skip the normal cleanup, we still need to
245 * make sure that the in-core orphan linked list is properly
248 ext4_orphan_del(NULL
, inode
);
249 sb_end_intwrite(inode
->i_sb
);
254 ext4_handle_sync(handle
);
256 err
= ext4_mark_inode_dirty(handle
, inode
);
258 ext4_warning(inode
->i_sb
,
259 "couldn't mark inode dirty (err %d)", err
);
263 ext4_truncate(inode
);
266 * ext4_ext_truncate() doesn't reserve any slop when it
267 * restarts journal transactions; therefore there may not be
268 * enough credits left in the handle to remove the inode from
269 * the orphan list and set the dtime field.
271 if (!ext4_handle_has_enough_credits(handle
, 3)) {
272 err
= ext4_journal_extend(handle
, 3);
274 err
= ext4_journal_restart(handle
, 3);
276 ext4_warning(inode
->i_sb
,
277 "couldn't extend journal (err %d)", err
);
279 ext4_journal_stop(handle
);
280 ext4_orphan_del(NULL
, inode
);
281 sb_end_intwrite(inode
->i_sb
);
287 * Kill off the orphan record which ext4_truncate created.
288 * AKPM: I think this can be inside the above `if'.
289 * Note that ext4_orphan_del() has to be able to cope with the
290 * deletion of a non-existent orphan - this is because we don't
291 * know if ext4_truncate() actually created an orphan record.
292 * (Well, we could do this if we need to, but heck - it works)
294 ext4_orphan_del(handle
, inode
);
295 EXT4_I(inode
)->i_dtime
= get_seconds();
298 * One subtle ordering requirement: if anything has gone wrong
299 * (transaction abort, IO errors, whatever), then we can still
300 * do these next steps (the fs will already have been marked as
301 * having errors), but we can't free the inode if the mark_dirty
304 if (ext4_mark_inode_dirty(handle
, inode
))
305 /* If that failed, just do the required in-core inode clear. */
306 ext4_clear_inode(inode
);
308 ext4_free_inode(handle
, inode
);
309 ext4_journal_stop(handle
);
310 sb_end_intwrite(inode
->i_sb
);
313 ext4_clear_inode(inode
); /* We must guarantee clearing of inode... */
317 qsize_t
*ext4_get_reserved_space(struct inode
*inode
)
319 return &EXT4_I(inode
)->i_reserved_quota
;
324 * Called with i_data_sem down, which is important since we can call
325 * ext4_discard_preallocations() from here.
327 void ext4_da_update_reserve_space(struct inode
*inode
,
328 int used
, int quota_claim
)
330 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
331 struct ext4_inode_info
*ei
= EXT4_I(inode
);
333 spin_lock(&ei
->i_block_reservation_lock
);
334 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
335 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
336 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
337 "with only %d reserved data blocks",
338 __func__
, inode
->i_ino
, used
,
339 ei
->i_reserved_data_blocks
);
341 used
= ei
->i_reserved_data_blocks
;
344 /* Update per-inode reservations */
345 ei
->i_reserved_data_blocks
-= used
;
346 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, used
);
348 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
350 /* Update quota subsystem for data blocks */
352 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
355 * We did fallocate with an offset that is already delayed
356 * allocated. So on delayed allocated writeback we should
357 * not re-claim the quota for fallocated blocks.
359 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
363 * If we have done all the pending block allocations and if
364 * there aren't any writers on the inode, we can discard the
365 * inode's preallocations.
367 if ((ei
->i_reserved_data_blocks
== 0) &&
368 (atomic_read(&inode
->i_writecount
) == 0))
369 ext4_discard_preallocations(inode
);
372 static int __check_block_validity(struct inode
*inode
, const char *func
,
374 struct ext4_map_blocks
*map
)
376 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
378 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
379 "lblock %lu mapped to illegal pblock "
380 "(length %d)", (unsigned long) map
->m_lblk
,
387 #define check_block_validity(inode, map) \
388 __check_block_validity((inode), __func__, __LINE__, (map))
390 #ifdef ES_AGGRESSIVE_TEST
391 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
393 struct ext4_map_blocks
*es_map
,
394 struct ext4_map_blocks
*map
,
401 * There is a race window that the result is not the same.
402 * e.g. xfstests #223 when dioread_nolock enables. The reason
403 * is that we lookup a block mapping in extent status tree with
404 * out taking i_data_sem. So at the time the unwritten extent
405 * could be converted.
407 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
408 down_read(&EXT4_I(inode
)->i_data_sem
);
409 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
410 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
411 EXT4_GET_BLOCKS_KEEP_SIZE
);
413 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
414 EXT4_GET_BLOCKS_KEEP_SIZE
);
416 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
417 up_read((&EXT4_I(inode
)->i_data_sem
));
420 * We don't check m_len because extent will be collpased in status
421 * tree. So the m_len might not equal.
423 if (es_map
->m_lblk
!= map
->m_lblk
||
424 es_map
->m_flags
!= map
->m_flags
||
425 es_map
->m_pblk
!= map
->m_pblk
) {
426 printk("ES cache assertion failed for inode: %lu "
427 "es_cached ex [%d/%d/%llu/%x] != "
428 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
429 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
430 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
431 map
->m_len
, map
->m_pblk
, map
->m_flags
,
435 #endif /* ES_AGGRESSIVE_TEST */
438 * The ext4_map_blocks() function tries to look up the requested blocks,
439 * and returns if the blocks are already mapped.
441 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
442 * and store the allocated blocks in the result buffer head and mark it
445 * If file type is extents based, it will call ext4_ext_map_blocks(),
446 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
449 * On success, it returns the number of blocks being mapped or allocated.
450 * if create==0 and the blocks are pre-allocated and unwritten block,
451 * the result buffer head is unmapped. If the create ==1, it will make sure
452 * the buffer head is mapped.
454 * It returns 0 if plain look up failed (blocks have not been allocated), in
455 * that case, buffer head is unmapped
457 * It returns the error in case of allocation failure.
459 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
460 struct ext4_map_blocks
*map
, int flags
)
462 struct extent_status es
;
465 #ifdef ES_AGGRESSIVE_TEST
466 struct ext4_map_blocks orig_map
;
468 memcpy(&orig_map
, map
, sizeof(*map
));
472 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
473 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
474 (unsigned long) map
->m_lblk
);
477 * ext4_map_blocks returns an int, and m_len is an unsigned int
479 if (unlikely(map
->m_len
> INT_MAX
))
480 map
->m_len
= INT_MAX
;
482 /* We can handle the block number less than EXT_MAX_BLOCKS */
483 if (unlikely(map
->m_lblk
>= EXT_MAX_BLOCKS
))
486 /* Lookup extent status tree firstly */
487 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
488 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
489 map
->m_pblk
= ext4_es_pblock(&es
) +
490 map
->m_lblk
- es
.es_lblk
;
491 map
->m_flags
|= ext4_es_is_written(&es
) ?
492 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
493 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
494 if (retval
> map
->m_len
)
497 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
502 #ifdef ES_AGGRESSIVE_TEST
503 ext4_map_blocks_es_recheck(handle
, inode
, map
,
510 * Try to see if we can get the block without requesting a new
513 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
514 down_read(&EXT4_I(inode
)->i_data_sem
);
515 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
516 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
517 EXT4_GET_BLOCKS_KEEP_SIZE
);
519 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
520 EXT4_GET_BLOCKS_KEEP_SIZE
);
525 if (unlikely(retval
!= map
->m_len
)) {
526 ext4_warning(inode
->i_sb
,
527 "ES len assertion failed for inode "
528 "%lu: retval %d != map->m_len %d",
529 inode
->i_ino
, retval
, map
->m_len
);
533 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
534 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
535 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
536 ext4_find_delalloc_range(inode
, map
->m_lblk
,
537 map
->m_lblk
+ map
->m_len
- 1))
538 status
|= EXTENT_STATUS_DELAYED
;
539 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
540 map
->m_len
, map
->m_pblk
, status
);
544 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
545 up_read((&EXT4_I(inode
)->i_data_sem
));
548 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
549 ret
= check_block_validity(inode
, map
);
554 /* If it is only a block(s) look up */
555 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
559 * Returns if the blocks have already allocated
561 * Note that if blocks have been preallocated
562 * ext4_ext_get_block() returns the create = 0
563 * with buffer head unmapped.
565 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
567 * If we need to convert extent to unwritten
568 * we continue and do the actual work in
569 * ext4_ext_map_blocks()
571 if (!(flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
))
575 * Here we clear m_flags because after allocating an new extent,
576 * it will be set again.
578 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
581 * New blocks allocate and/or writing to unwritten extent
582 * will possibly result in updating i_data, so we take
583 * the write lock of i_data_sem, and call get_block()
584 * with create == 1 flag.
586 down_write(&EXT4_I(inode
)->i_data_sem
);
589 * We need to check for EXT4 here because migrate
590 * could have changed the inode type in between
592 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
593 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
595 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
597 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
599 * We allocated new blocks which will result in
600 * i_data's format changing. Force the migrate
601 * to fail by clearing migrate flags
603 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
607 * Update reserved blocks/metadata blocks after successful
608 * block allocation which had been deferred till now. We don't
609 * support fallocate for non extent files. So we can update
610 * reserve space here.
613 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
614 ext4_da_update_reserve_space(inode
, retval
, 1);
620 if (unlikely(retval
!= map
->m_len
)) {
621 ext4_warning(inode
->i_sb
,
622 "ES len assertion failed for inode "
623 "%lu: retval %d != map->m_len %d",
624 inode
->i_ino
, retval
, map
->m_len
);
629 * If the extent has been zeroed out, we don't need to update
630 * extent status tree.
632 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
633 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
634 if (ext4_es_is_written(&es
))
637 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
638 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
639 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
640 ext4_find_delalloc_range(inode
, map
->m_lblk
,
641 map
->m_lblk
+ map
->m_len
- 1))
642 status
|= EXTENT_STATUS_DELAYED
;
643 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
644 map
->m_pblk
, status
);
650 up_write((&EXT4_I(inode
)->i_data_sem
));
651 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
652 ret
= check_block_validity(inode
, map
);
659 static void ext4_end_io_unwritten(struct buffer_head
*bh
, int uptodate
)
661 struct inode
*inode
= bh
->b_assoc_map
->host
;
662 /* XXX: breaks on 32-bit > 16GB. Is that even supported? */
663 loff_t offset
= (loff_t
)(uintptr_t)bh
->b_private
<< inode
->i_blkbits
;
667 WARN_ON(!buffer_unwritten(bh
));
668 err
= ext4_convert_unwritten_extents(NULL
, inode
, offset
, bh
->b_size
);
671 /* Maximum number of blocks we map for direct IO at once. */
672 #define DIO_MAX_BLOCKS 4096
674 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
675 struct buffer_head
*bh
, int flags
)
677 handle_t
*handle
= ext4_journal_current_handle();
678 struct ext4_map_blocks map
;
679 int ret
= 0, started
= 0;
682 if (ext4_has_inline_data(inode
))
686 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
688 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
689 /* Direct IO write... */
690 if (map
.m_len
> DIO_MAX_BLOCKS
)
691 map
.m_len
= DIO_MAX_BLOCKS
;
692 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
693 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
695 if (IS_ERR(handle
)) {
696 ret
= PTR_ERR(handle
);
702 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
704 ext4_io_end_t
*io_end
= ext4_inode_aio(inode
);
706 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
707 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
708 if (IS_DAX(inode
) && buffer_unwritten(bh
) && !io_end
) {
709 bh
->b_assoc_map
= inode
->i_mapping
;
710 bh
->b_private
= (void *)(unsigned long)iblock
;
711 bh
->b_end_io
= ext4_end_io_unwritten
;
713 if (io_end
&& io_end
->flag
& EXT4_IO_END_UNWRITTEN
)
714 set_buffer_defer_completion(bh
);
715 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
719 ext4_journal_stop(handle
);
723 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
724 struct buffer_head
*bh
, int create
)
726 return _ext4_get_block(inode
, iblock
, bh
,
727 create
? EXT4_GET_BLOCKS_CREATE
: 0);
731 * `handle' can be NULL if create is zero
733 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
734 ext4_lblk_t block
, int create
)
736 struct ext4_map_blocks map
;
737 struct buffer_head
*bh
;
740 J_ASSERT(handle
!= NULL
|| create
== 0);
744 err
= ext4_map_blocks(handle
, inode
, &map
,
745 create
? EXT4_GET_BLOCKS_CREATE
: 0);
748 return create
? ERR_PTR(-ENOSPC
) : NULL
;
752 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
754 return ERR_PTR(-ENOMEM
);
755 if (map
.m_flags
& EXT4_MAP_NEW
) {
756 J_ASSERT(create
!= 0);
757 J_ASSERT(handle
!= NULL
);
760 * Now that we do not always journal data, we should
761 * keep in mind whether this should always journal the
762 * new buffer as metadata. For now, regular file
763 * writes use ext4_get_block instead, so it's not a
767 BUFFER_TRACE(bh
, "call get_create_access");
768 err
= ext4_journal_get_create_access(handle
, bh
);
773 if (!buffer_uptodate(bh
)) {
774 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
775 set_buffer_uptodate(bh
);
778 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
779 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
783 BUFFER_TRACE(bh
, "not a new buffer");
790 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
791 ext4_lblk_t block
, int create
)
793 struct buffer_head
*bh
;
795 bh
= ext4_getblk(handle
, inode
, block
, create
);
798 if (!bh
|| buffer_uptodate(bh
))
800 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
802 if (buffer_uptodate(bh
))
805 return ERR_PTR(-EIO
);
808 int ext4_walk_page_buffers(handle_t
*handle
,
809 struct buffer_head
*head
,
813 int (*fn
)(handle_t
*handle
,
814 struct buffer_head
*bh
))
816 struct buffer_head
*bh
;
817 unsigned block_start
, block_end
;
818 unsigned blocksize
= head
->b_size
;
820 struct buffer_head
*next
;
822 for (bh
= head
, block_start
= 0;
823 ret
== 0 && (bh
!= head
|| !block_start
);
824 block_start
= block_end
, bh
= next
) {
825 next
= bh
->b_this_page
;
826 block_end
= block_start
+ blocksize
;
827 if (block_end
<= from
|| block_start
>= to
) {
828 if (partial
&& !buffer_uptodate(bh
))
832 err
= (*fn
)(handle
, bh
);
840 * To preserve ordering, it is essential that the hole instantiation and
841 * the data write be encapsulated in a single transaction. We cannot
842 * close off a transaction and start a new one between the ext4_get_block()
843 * and the commit_write(). So doing the jbd2_journal_start at the start of
844 * prepare_write() is the right place.
846 * Also, this function can nest inside ext4_writepage(). In that case, we
847 * *know* that ext4_writepage() has generated enough buffer credits to do the
848 * whole page. So we won't block on the journal in that case, which is good,
849 * because the caller may be PF_MEMALLOC.
851 * By accident, ext4 can be reentered when a transaction is open via
852 * quota file writes. If we were to commit the transaction while thus
853 * reentered, there can be a deadlock - we would be holding a quota
854 * lock, and the commit would never complete if another thread had a
855 * transaction open and was blocking on the quota lock - a ranking
858 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
859 * will _not_ run commit under these circumstances because handle->h_ref
860 * is elevated. We'll still have enough credits for the tiny quotafile
863 int do_journal_get_write_access(handle_t
*handle
,
864 struct buffer_head
*bh
)
866 int dirty
= buffer_dirty(bh
);
869 if (!buffer_mapped(bh
) || buffer_freed(bh
))
872 * __block_write_begin() could have dirtied some buffers. Clean
873 * the dirty bit as jbd2_journal_get_write_access() could complain
874 * otherwise about fs integrity issues. Setting of the dirty bit
875 * by __block_write_begin() isn't a real problem here as we clear
876 * the bit before releasing a page lock and thus writeback cannot
877 * ever write the buffer.
880 clear_buffer_dirty(bh
);
881 BUFFER_TRACE(bh
, "get write access");
882 ret
= ext4_journal_get_write_access(handle
, bh
);
884 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
888 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
889 struct buffer_head
*bh_result
, int create
);
890 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
891 loff_t pos
, unsigned len
, unsigned flags
,
892 struct page
**pagep
, void **fsdata
)
894 struct inode
*inode
= mapping
->host
;
895 int ret
, needed_blocks
;
902 trace_ext4_write_begin(inode
, pos
, len
, flags
);
904 * Reserve one block more for addition to orphan list in case
905 * we allocate blocks but write fails for some reason
907 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
908 index
= pos
>> PAGE_CACHE_SHIFT
;
909 from
= pos
& (PAGE_CACHE_SIZE
- 1);
912 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
913 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
922 * grab_cache_page_write_begin() can take a long time if the
923 * system is thrashing due to memory pressure, or if the page
924 * is being written back. So grab it first before we start
925 * the transaction handle. This also allows us to allocate
926 * the page (if needed) without using GFP_NOFS.
929 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
935 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
936 if (IS_ERR(handle
)) {
937 page_cache_release(page
);
938 return PTR_ERR(handle
);
942 if (page
->mapping
!= mapping
) {
943 /* The page got truncated from under us */
945 page_cache_release(page
);
946 ext4_journal_stop(handle
);
949 /* In case writeback began while the page was unlocked */
950 wait_for_stable_page(page
);
952 if (ext4_should_dioread_nolock(inode
))
953 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
955 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
957 if (!ret
&& ext4_should_journal_data(inode
)) {
958 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
960 do_journal_get_write_access
);
966 * __block_write_begin may have instantiated a few blocks
967 * outside i_size. Trim these off again. Don't need
968 * i_size_read because we hold i_mutex.
970 * Add inode to orphan list in case we crash before
973 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
974 ext4_orphan_add(handle
, inode
);
976 ext4_journal_stop(handle
);
977 if (pos
+ len
> inode
->i_size
) {
978 ext4_truncate_failed_write(inode
);
980 * If truncate failed early the inode might
981 * still be on the orphan list; we need to
982 * make sure the inode is removed from the
983 * orphan list in that case.
986 ext4_orphan_del(NULL
, inode
);
989 if (ret
== -ENOSPC
&&
990 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
992 page_cache_release(page
);
999 /* For write_end() in data=journal mode */
1000 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1003 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1005 set_buffer_uptodate(bh
);
1006 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1007 clear_buffer_meta(bh
);
1008 clear_buffer_prio(bh
);
1013 * We need to pick up the new inode size which generic_commit_write gave us
1014 * `file' can be NULL - eg, when called from page_symlink().
1016 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1017 * buffers are managed internally.
1019 static int ext4_write_end(struct file
*file
,
1020 struct address_space
*mapping
,
1021 loff_t pos
, unsigned len
, unsigned copied
,
1022 struct page
*page
, void *fsdata
)
1024 handle_t
*handle
= ext4_journal_current_handle();
1025 struct inode
*inode
= mapping
->host
;
1027 int i_size_changed
= 0;
1029 trace_ext4_write_end(inode
, pos
, len
, copied
);
1030 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1031 ret
= ext4_jbd2_file_inode(handle
, inode
);
1034 page_cache_release(page
);
1039 if (ext4_has_inline_data(inode
)) {
1040 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1046 copied
= block_write_end(file
, mapping
, pos
,
1047 len
, copied
, page
, fsdata
);
1049 * it's important to update i_size while still holding page lock:
1050 * page writeout could otherwise come in and zero beyond i_size.
1052 i_size_changed
= ext4_update_inode_size(inode
, pos
+ copied
);
1054 page_cache_release(page
);
1057 * Don't mark the inode dirty under page lock. First, it unnecessarily
1058 * makes the holding time of page lock longer. Second, it forces lock
1059 * ordering of page lock and transaction start for journaling
1063 ext4_mark_inode_dirty(handle
, inode
);
1065 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1066 /* if we have allocated more blocks and copied
1067 * less. We will have blocks allocated outside
1068 * inode->i_size. So truncate them
1070 ext4_orphan_add(handle
, inode
);
1072 ret2
= ext4_journal_stop(handle
);
1076 if (pos
+ len
> inode
->i_size
) {
1077 ext4_truncate_failed_write(inode
);
1079 * If truncate failed early the inode might still be
1080 * on the orphan list; we need to make sure the inode
1081 * is removed from the orphan list in that case.
1084 ext4_orphan_del(NULL
, inode
);
1087 return ret
? ret
: copied
;
1090 static int ext4_journalled_write_end(struct file
*file
,
1091 struct address_space
*mapping
,
1092 loff_t pos
, unsigned len
, unsigned copied
,
1093 struct page
*page
, void *fsdata
)
1095 handle_t
*handle
= ext4_journal_current_handle();
1096 struct inode
*inode
= mapping
->host
;
1100 int size_changed
= 0;
1102 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1103 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1106 BUG_ON(!ext4_handle_valid(handle
));
1108 if (ext4_has_inline_data(inode
))
1109 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1113 if (!PageUptodate(page
))
1115 page_zero_new_buffers(page
, from
+copied
, to
);
1118 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1119 to
, &partial
, write_end_fn
);
1121 SetPageUptodate(page
);
1123 size_changed
= ext4_update_inode_size(inode
, pos
+ copied
);
1124 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1125 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1127 page_cache_release(page
);
1130 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1135 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1136 /* if we have allocated more blocks and copied
1137 * less. We will have blocks allocated outside
1138 * inode->i_size. So truncate them
1140 ext4_orphan_add(handle
, inode
);
1142 ret2
= ext4_journal_stop(handle
);
1145 if (pos
+ len
> inode
->i_size
) {
1146 ext4_truncate_failed_write(inode
);
1148 * If truncate failed early the inode might still be
1149 * on the orphan list; we need to make sure the inode
1150 * is removed from the orphan list in that case.
1153 ext4_orphan_del(NULL
, inode
);
1156 return ret
? ret
: copied
;
1160 * Reserve a single cluster located at lblock
1162 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1164 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1165 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1166 unsigned int md_needed
;
1170 * We will charge metadata quota at writeout time; this saves
1171 * us from metadata over-estimation, though we may go over by
1172 * a small amount in the end. Here we just reserve for data.
1174 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1179 * recalculate the amount of metadata blocks to reserve
1180 * in order to allocate nrblocks
1181 * worse case is one extent per block
1183 spin_lock(&ei
->i_block_reservation_lock
);
1185 * ext4_calc_metadata_amount() has side effects, which we have
1186 * to be prepared undo if we fail to claim space.
1189 trace_ext4_da_reserve_space(inode
, 0);
1191 if (ext4_claim_free_clusters(sbi
, 1, 0)) {
1192 spin_unlock(&ei
->i_block_reservation_lock
);
1193 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1196 ei
->i_reserved_data_blocks
++;
1197 spin_unlock(&ei
->i_block_reservation_lock
);
1199 return 0; /* success */
1202 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1204 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1205 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1208 return; /* Nothing to release, exit */
1210 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1212 trace_ext4_da_release_space(inode
, to_free
);
1213 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1215 * if there aren't enough reserved blocks, then the
1216 * counter is messed up somewhere. Since this
1217 * function is called from invalidate page, it's
1218 * harmless to return without any action.
1220 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1221 "ino %lu, to_free %d with only %d reserved "
1222 "data blocks", inode
->i_ino
, to_free
,
1223 ei
->i_reserved_data_blocks
);
1225 to_free
= ei
->i_reserved_data_blocks
;
1227 ei
->i_reserved_data_blocks
-= to_free
;
1229 /* update fs dirty data blocks counter */
1230 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1232 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1234 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1237 static void ext4_da_page_release_reservation(struct page
*page
,
1238 unsigned int offset
,
1239 unsigned int length
)
1242 struct buffer_head
*head
, *bh
;
1243 unsigned int curr_off
= 0;
1244 struct inode
*inode
= page
->mapping
->host
;
1245 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1246 unsigned int stop
= offset
+ length
;
1250 BUG_ON(stop
> PAGE_CACHE_SIZE
|| stop
< length
);
1252 head
= page_buffers(page
);
1255 unsigned int next_off
= curr_off
+ bh
->b_size
;
1257 if (next_off
> stop
)
1260 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1262 clear_buffer_delay(bh
);
1264 curr_off
= next_off
;
1265 } while ((bh
= bh
->b_this_page
) != head
);
1268 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1269 ext4_es_remove_extent(inode
, lblk
, to_release
);
1272 /* If we have released all the blocks belonging to a cluster, then we
1273 * need to release the reserved space for that cluster. */
1274 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1275 while (num_clusters
> 0) {
1276 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1277 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1278 if (sbi
->s_cluster_ratio
== 1 ||
1279 !ext4_find_delalloc_cluster(inode
, lblk
))
1280 ext4_da_release_space(inode
, 1);
1287 * Delayed allocation stuff
1290 struct mpage_da_data
{
1291 struct inode
*inode
;
1292 struct writeback_control
*wbc
;
1294 pgoff_t first_page
; /* The first page to write */
1295 pgoff_t next_page
; /* Current page to examine */
1296 pgoff_t last_page
; /* Last page to examine */
1298 * Extent to map - this can be after first_page because that can be
1299 * fully mapped. We somewhat abuse m_flags to store whether the extent
1300 * is delalloc or unwritten.
1302 struct ext4_map_blocks map
;
1303 struct ext4_io_submit io_submit
; /* IO submission data */
1306 static void mpage_release_unused_pages(struct mpage_da_data
*mpd
,
1311 struct pagevec pvec
;
1312 struct inode
*inode
= mpd
->inode
;
1313 struct address_space
*mapping
= inode
->i_mapping
;
1315 /* This is necessary when next_page == 0. */
1316 if (mpd
->first_page
>= mpd
->next_page
)
1319 index
= mpd
->first_page
;
1320 end
= mpd
->next_page
- 1;
1322 ext4_lblk_t start
, last
;
1323 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1324 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1325 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1328 pagevec_init(&pvec
, 0);
1329 while (index
<= end
) {
1330 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1333 for (i
= 0; i
< nr_pages
; i
++) {
1334 struct page
*page
= pvec
.pages
[i
];
1335 if (page
->index
> end
)
1337 BUG_ON(!PageLocked(page
));
1338 BUG_ON(PageWriteback(page
));
1340 block_invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
1341 ClearPageUptodate(page
);
1345 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1346 pagevec_release(&pvec
);
1350 static void ext4_print_free_blocks(struct inode
*inode
)
1352 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1353 struct super_block
*sb
= inode
->i_sb
;
1354 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1356 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1357 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1358 ext4_count_free_clusters(sb
)));
1359 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1360 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1361 (long long) EXT4_C2B(EXT4_SB(sb
),
1362 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1363 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1364 (long long) EXT4_C2B(EXT4_SB(sb
),
1365 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1366 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1367 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1368 ei
->i_reserved_data_blocks
);
1372 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1374 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1378 * This function is grabs code from the very beginning of
1379 * ext4_map_blocks, but assumes that the caller is from delayed write
1380 * time. This function looks up the requested blocks and sets the
1381 * buffer delay bit under the protection of i_data_sem.
1383 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1384 struct ext4_map_blocks
*map
,
1385 struct buffer_head
*bh
)
1387 struct extent_status es
;
1389 sector_t invalid_block
= ~((sector_t
) 0xffff);
1390 #ifdef ES_AGGRESSIVE_TEST
1391 struct ext4_map_blocks orig_map
;
1393 memcpy(&orig_map
, map
, sizeof(*map
));
1396 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1400 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1401 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1402 (unsigned long) map
->m_lblk
);
1404 /* Lookup extent status tree firstly */
1405 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1406 if (ext4_es_is_hole(&es
)) {
1408 down_read(&EXT4_I(inode
)->i_data_sem
);
1413 * Delayed extent could be allocated by fallocate.
1414 * So we need to check it.
1416 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1417 map_bh(bh
, inode
->i_sb
, invalid_block
);
1419 set_buffer_delay(bh
);
1423 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1424 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1425 if (retval
> map
->m_len
)
1426 retval
= map
->m_len
;
1427 map
->m_len
= retval
;
1428 if (ext4_es_is_written(&es
))
1429 map
->m_flags
|= EXT4_MAP_MAPPED
;
1430 else if (ext4_es_is_unwritten(&es
))
1431 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1435 #ifdef ES_AGGRESSIVE_TEST
1436 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1442 * Try to see if we can get the block without requesting a new
1443 * file system block.
1445 down_read(&EXT4_I(inode
)->i_data_sem
);
1446 if (ext4_has_inline_data(inode
))
1448 else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1449 retval
= ext4_ext_map_blocks(NULL
, inode
, map
, 0);
1451 retval
= ext4_ind_map_blocks(NULL
, inode
, map
, 0);
1457 * XXX: __block_prepare_write() unmaps passed block,
1461 * If the block was allocated from previously allocated cluster,
1462 * then we don't need to reserve it again. However we still need
1463 * to reserve metadata for every block we're going to write.
1465 if (EXT4_SB(inode
->i_sb
)->s_cluster_ratio
<= 1 ||
1466 !ext4_find_delalloc_cluster(inode
, map
->m_lblk
)) {
1467 ret
= ext4_da_reserve_space(inode
, iblock
);
1469 /* not enough space to reserve */
1475 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1476 ~0, EXTENT_STATUS_DELAYED
);
1482 map_bh(bh
, inode
->i_sb
, invalid_block
);
1484 set_buffer_delay(bh
);
1485 } else if (retval
> 0) {
1487 unsigned int status
;
1489 if (unlikely(retval
!= map
->m_len
)) {
1490 ext4_warning(inode
->i_sb
,
1491 "ES len assertion failed for inode "
1492 "%lu: retval %d != map->m_len %d",
1493 inode
->i_ino
, retval
, map
->m_len
);
1497 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
1498 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
1499 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1500 map
->m_pblk
, status
);
1506 up_read((&EXT4_I(inode
)->i_data_sem
));
1512 * This is a special get_block_t callback which is used by
1513 * ext4_da_write_begin(). It will either return mapped block or
1514 * reserve space for a single block.
1516 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
1517 * We also have b_blocknr = -1 and b_bdev initialized properly
1519 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
1520 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
1521 * initialized properly.
1523 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
1524 struct buffer_head
*bh
, int create
)
1526 struct ext4_map_blocks map
;
1529 BUG_ON(create
== 0);
1530 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
1532 map
.m_lblk
= iblock
;
1536 * first, we need to know whether the block is allocated already
1537 * preallocated blocks are unmapped but should treated
1538 * the same as allocated blocks.
1540 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
1544 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
1545 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
1547 if (buffer_unwritten(bh
)) {
1548 /* A delayed write to unwritten bh should be marked
1549 * new and mapped. Mapped ensures that we don't do
1550 * get_block multiple times when we write to the same
1551 * offset and new ensures that we do proper zero out
1552 * for partial write.
1555 set_buffer_mapped(bh
);
1560 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1566 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1572 static int __ext4_journalled_writepage(struct page
*page
,
1575 struct address_space
*mapping
= page
->mapping
;
1576 struct inode
*inode
= mapping
->host
;
1577 struct buffer_head
*page_bufs
= NULL
;
1578 handle_t
*handle
= NULL
;
1579 int ret
= 0, err
= 0;
1580 int inline_data
= ext4_has_inline_data(inode
);
1581 struct buffer_head
*inode_bh
= NULL
;
1583 ClearPageChecked(page
);
1586 BUG_ON(page
->index
!= 0);
1587 BUG_ON(len
> ext4_get_max_inline_size(inode
));
1588 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
1589 if (inode_bh
== NULL
)
1592 page_bufs
= page_buffers(page
);
1597 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
1600 /* As soon as we unlock the page, it can go away, but we have
1601 * references to buffers so we are safe */
1604 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
1605 ext4_writepage_trans_blocks(inode
));
1606 if (IS_ERR(handle
)) {
1607 ret
= PTR_ERR(handle
);
1611 BUG_ON(!ext4_handle_valid(handle
));
1614 BUFFER_TRACE(inode_bh
, "get write access");
1615 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
1617 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
1620 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1621 do_journal_get_write_access
);
1623 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1628 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1629 err
= ext4_journal_stop(handle
);
1633 if (!ext4_has_inline_data(inode
))
1634 ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
,
1636 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1643 * Note that we don't need to start a transaction unless we're journaling data
1644 * because we should have holes filled from ext4_page_mkwrite(). We even don't
1645 * need to file the inode to the transaction's list in ordered mode because if
1646 * we are writing back data added by write(), the inode is already there and if
1647 * we are writing back data modified via mmap(), no one guarantees in which
1648 * transaction the data will hit the disk. In case we are journaling data, we
1649 * cannot start transaction directly because transaction start ranks above page
1650 * lock so we have to do some magic.
1652 * This function can get called via...
1653 * - ext4_writepages after taking page lock (have journal handle)
1654 * - journal_submit_inode_data_buffers (no journal handle)
1655 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
1656 * - grab_page_cache when doing write_begin (have journal handle)
1658 * We don't do any block allocation in this function. If we have page with
1659 * multiple blocks we need to write those buffer_heads that are mapped. This
1660 * is important for mmaped based write. So if we do with blocksize 1K
1661 * truncate(f, 1024);
1662 * a = mmap(f, 0, 4096);
1664 * truncate(f, 4096);
1665 * we have in the page first buffer_head mapped via page_mkwrite call back
1666 * but other buffer_heads would be unmapped but dirty (dirty done via the
1667 * do_wp_page). So writepage should write the first block. If we modify
1668 * the mmap area beyond 1024 we will again get a page_fault and the
1669 * page_mkwrite callback will do the block allocation and mark the
1670 * buffer_heads mapped.
1672 * We redirty the page if we have any buffer_heads that is either delay or
1673 * unwritten in the page.
1675 * We can get recursively called as show below.
1677 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1680 * But since we don't do any block allocation we should not deadlock.
1681 * Page also have the dirty flag cleared so we don't get recurive page_lock.
1683 static int ext4_writepage(struct page
*page
,
1684 struct writeback_control
*wbc
)
1689 struct buffer_head
*page_bufs
= NULL
;
1690 struct inode
*inode
= page
->mapping
->host
;
1691 struct ext4_io_submit io_submit
;
1692 bool keep_towrite
= false;
1694 trace_ext4_writepage(page
);
1695 size
= i_size_read(inode
);
1696 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1697 len
= size
& ~PAGE_CACHE_MASK
;
1699 len
= PAGE_CACHE_SIZE
;
1701 page_bufs
= page_buffers(page
);
1703 * We cannot do block allocation or other extent handling in this
1704 * function. If there are buffers needing that, we have to redirty
1705 * the page. But we may reach here when we do a journal commit via
1706 * journal_submit_inode_data_buffers() and in that case we must write
1707 * allocated buffers to achieve data=ordered mode guarantees.
1709 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
1710 ext4_bh_delay_or_unwritten
)) {
1711 redirty_page_for_writepage(wbc
, page
);
1712 if (current
->flags
& PF_MEMALLOC
) {
1714 * For memory cleaning there's no point in writing only
1715 * some buffers. So just bail out. Warn if we came here
1716 * from direct reclaim.
1718 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
1723 keep_towrite
= true;
1726 if (PageChecked(page
) && ext4_should_journal_data(inode
))
1728 * It's mmapped pagecache. Add buffers and journal it. There
1729 * doesn't seem much point in redirtying the page here.
1731 return __ext4_journalled_writepage(page
, len
);
1733 ext4_io_submit_init(&io_submit
, wbc
);
1734 io_submit
.io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
1735 if (!io_submit
.io_end
) {
1736 redirty_page_for_writepage(wbc
, page
);
1740 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
, keep_towrite
);
1741 ext4_io_submit(&io_submit
);
1742 /* Drop io_end reference we got from init */
1743 ext4_put_io_end_defer(io_submit
.io_end
);
1747 static int mpage_submit_page(struct mpage_da_data
*mpd
, struct page
*page
)
1750 loff_t size
= i_size_read(mpd
->inode
);
1753 BUG_ON(page
->index
!= mpd
->first_page
);
1754 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1755 len
= size
& ~PAGE_CACHE_MASK
;
1757 len
= PAGE_CACHE_SIZE
;
1758 clear_page_dirty_for_io(page
);
1759 err
= ext4_bio_write_page(&mpd
->io_submit
, page
, len
, mpd
->wbc
, false);
1761 mpd
->wbc
->nr_to_write
--;
1767 #define BH_FLAGS ((1 << BH_Unwritten) | (1 << BH_Delay))
1770 * mballoc gives us at most this number of blocks...
1771 * XXX: That seems to be only a limitation of ext4_mb_normalize_request().
1772 * The rest of mballoc seems to handle chunks up to full group size.
1774 #define MAX_WRITEPAGES_EXTENT_LEN 2048
1777 * mpage_add_bh_to_extent - try to add bh to extent of blocks to map
1779 * @mpd - extent of blocks
1780 * @lblk - logical number of the block in the file
1781 * @bh - buffer head we want to add to the extent
1783 * The function is used to collect contig. blocks in the same state. If the
1784 * buffer doesn't require mapping for writeback and we haven't started the
1785 * extent of buffers to map yet, the function returns 'true' immediately - the
1786 * caller can write the buffer right away. Otherwise the function returns true
1787 * if the block has been added to the extent, false if the block couldn't be
1790 static bool mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, ext4_lblk_t lblk
,
1791 struct buffer_head
*bh
)
1793 struct ext4_map_blocks
*map
= &mpd
->map
;
1795 /* Buffer that doesn't need mapping for writeback? */
1796 if (!buffer_dirty(bh
) || !buffer_mapped(bh
) ||
1797 (!buffer_delay(bh
) && !buffer_unwritten(bh
))) {
1798 /* So far no extent to map => we write the buffer right away */
1799 if (map
->m_len
== 0)
1804 /* First block in the extent? */
1805 if (map
->m_len
== 0) {
1808 map
->m_flags
= bh
->b_state
& BH_FLAGS
;
1812 /* Don't go larger than mballoc is willing to allocate */
1813 if (map
->m_len
>= MAX_WRITEPAGES_EXTENT_LEN
)
1816 /* Can we merge the block to our big extent? */
1817 if (lblk
== map
->m_lblk
+ map
->m_len
&&
1818 (bh
->b_state
& BH_FLAGS
) == map
->m_flags
) {
1826 * mpage_process_page_bufs - submit page buffers for IO or add them to extent
1828 * @mpd - extent of blocks for mapping
1829 * @head - the first buffer in the page
1830 * @bh - buffer we should start processing from
1831 * @lblk - logical number of the block in the file corresponding to @bh
1833 * Walk through page buffers from @bh upto @head (exclusive) and either submit
1834 * the page for IO if all buffers in this page were mapped and there's no
1835 * accumulated extent of buffers to map or add buffers in the page to the
1836 * extent of buffers to map. The function returns 1 if the caller can continue
1837 * by processing the next page, 0 if it should stop adding buffers to the
1838 * extent to map because we cannot extend it anymore. It can also return value
1839 * < 0 in case of error during IO submission.
1841 static int mpage_process_page_bufs(struct mpage_da_data
*mpd
,
1842 struct buffer_head
*head
,
1843 struct buffer_head
*bh
,
1846 struct inode
*inode
= mpd
->inode
;
1848 ext4_lblk_t blocks
= (i_size_read(inode
) + (1 << inode
->i_blkbits
) - 1)
1849 >> inode
->i_blkbits
;
1852 BUG_ON(buffer_locked(bh
));
1854 if (lblk
>= blocks
|| !mpage_add_bh_to_extent(mpd
, lblk
, bh
)) {
1855 /* Found extent to map? */
1858 /* Everything mapped so far and we hit EOF */
1861 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
1862 /* So far everything mapped? Submit the page for IO. */
1863 if (mpd
->map
.m_len
== 0) {
1864 err
= mpage_submit_page(mpd
, head
->b_page
);
1868 return lblk
< blocks
;
1872 * mpage_map_buffers - update buffers corresponding to changed extent and
1873 * submit fully mapped pages for IO
1875 * @mpd - description of extent to map, on return next extent to map
1877 * Scan buffers corresponding to changed extent (we expect corresponding pages
1878 * to be already locked) and update buffer state according to new extent state.
1879 * We map delalloc buffers to their physical location, clear unwritten bits,
1880 * and mark buffers as uninit when we perform writes to unwritten extents
1881 * and do extent conversion after IO is finished. If the last page is not fully
1882 * mapped, we update @map to the next extent in the last page that needs
1883 * mapping. Otherwise we submit the page for IO.
1885 static int mpage_map_and_submit_buffers(struct mpage_da_data
*mpd
)
1887 struct pagevec pvec
;
1889 struct inode
*inode
= mpd
->inode
;
1890 struct buffer_head
*head
, *bh
;
1891 int bpp_bits
= PAGE_CACHE_SHIFT
- inode
->i_blkbits
;
1897 start
= mpd
->map
.m_lblk
>> bpp_bits
;
1898 end
= (mpd
->map
.m_lblk
+ mpd
->map
.m_len
- 1) >> bpp_bits
;
1899 lblk
= start
<< bpp_bits
;
1900 pblock
= mpd
->map
.m_pblk
;
1902 pagevec_init(&pvec
, 0);
1903 while (start
<= end
) {
1904 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, start
,
1908 for (i
= 0; i
< nr_pages
; i
++) {
1909 struct page
*page
= pvec
.pages
[i
];
1911 if (page
->index
> end
)
1913 /* Up to 'end' pages must be contiguous */
1914 BUG_ON(page
->index
!= start
);
1915 bh
= head
= page_buffers(page
);
1917 if (lblk
< mpd
->map
.m_lblk
)
1919 if (lblk
>= mpd
->map
.m_lblk
+ mpd
->map
.m_len
) {
1921 * Buffer after end of mapped extent.
1922 * Find next buffer in the page to map.
1925 mpd
->map
.m_flags
= 0;
1927 * FIXME: If dioread_nolock supports
1928 * blocksize < pagesize, we need to make
1929 * sure we add size mapped so far to
1930 * io_end->size as the following call
1931 * can submit the page for IO.
1933 err
= mpage_process_page_bufs(mpd
, head
,
1935 pagevec_release(&pvec
);
1940 if (buffer_delay(bh
)) {
1941 clear_buffer_delay(bh
);
1942 bh
->b_blocknr
= pblock
++;
1944 clear_buffer_unwritten(bh
);
1945 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
1948 * FIXME: This is going to break if dioread_nolock
1949 * supports blocksize < pagesize as we will try to
1950 * convert potentially unmapped parts of inode.
1952 mpd
->io_submit
.io_end
->size
+= PAGE_CACHE_SIZE
;
1953 /* Page fully mapped - let IO run! */
1954 err
= mpage_submit_page(mpd
, page
);
1956 pagevec_release(&pvec
);
1961 pagevec_release(&pvec
);
1963 /* Extent fully mapped and matches with page boundary. We are done. */
1965 mpd
->map
.m_flags
= 0;
1969 static int mpage_map_one_extent(handle_t
*handle
, struct mpage_da_data
*mpd
)
1971 struct inode
*inode
= mpd
->inode
;
1972 struct ext4_map_blocks
*map
= &mpd
->map
;
1973 int get_blocks_flags
;
1974 int err
, dioread_nolock
;
1976 trace_ext4_da_write_pages_extent(inode
, map
);
1978 * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
1979 * to convert an unwritten extent to be initialized (in the case
1980 * where we have written into one or more preallocated blocks). It is
1981 * possible that we're going to need more metadata blocks than
1982 * previously reserved. However we must not fail because we're in
1983 * writeback and there is nothing we can do about it so it might result
1984 * in data loss. So use reserved blocks to allocate metadata if
1987 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if
1988 * the blocks in question are delalloc blocks. This indicates
1989 * that the blocks and quotas has already been checked when
1990 * the data was copied into the page cache.
1992 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
1993 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
1994 dioread_nolock
= ext4_should_dioread_nolock(inode
);
1996 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
1997 if (map
->m_flags
& (1 << BH_Delay
))
1998 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
2000 err
= ext4_map_blocks(handle
, inode
, map
, get_blocks_flags
);
2003 if (dioread_nolock
&& (map
->m_flags
& EXT4_MAP_UNWRITTEN
)) {
2004 if (!mpd
->io_submit
.io_end
->handle
&&
2005 ext4_handle_valid(handle
)) {
2006 mpd
->io_submit
.io_end
->handle
= handle
->h_rsv_handle
;
2007 handle
->h_rsv_handle
= NULL
;
2009 ext4_set_io_unwritten_flag(inode
, mpd
->io_submit
.io_end
);
2012 BUG_ON(map
->m_len
== 0);
2013 if (map
->m_flags
& EXT4_MAP_NEW
) {
2014 struct block_device
*bdev
= inode
->i_sb
->s_bdev
;
2017 for (i
= 0; i
< map
->m_len
; i
++)
2018 unmap_underlying_metadata(bdev
, map
->m_pblk
+ i
);
2024 * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
2025 * mpd->len and submit pages underlying it for IO
2027 * @handle - handle for journal operations
2028 * @mpd - extent to map
2029 * @give_up_on_write - we set this to true iff there is a fatal error and there
2030 * is no hope of writing the data. The caller should discard
2031 * dirty pages to avoid infinite loops.
2033 * The function maps extent starting at mpd->lblk of length mpd->len. If it is
2034 * delayed, blocks are allocated, if it is unwritten, we may need to convert
2035 * them to initialized or split the described range from larger unwritten
2036 * extent. Note that we need not map all the described range since allocation
2037 * can return less blocks or the range is covered by more unwritten extents. We
2038 * cannot map more because we are limited by reserved transaction credits. On
2039 * the other hand we always make sure that the last touched page is fully
2040 * mapped so that it can be written out (and thus forward progress is
2041 * guaranteed). After mapping we submit all mapped pages for IO.
2043 static int mpage_map_and_submit_extent(handle_t
*handle
,
2044 struct mpage_da_data
*mpd
,
2045 bool *give_up_on_write
)
2047 struct inode
*inode
= mpd
->inode
;
2048 struct ext4_map_blocks
*map
= &mpd
->map
;
2053 mpd
->io_submit
.io_end
->offset
=
2054 ((loff_t
)map
->m_lblk
) << inode
->i_blkbits
;
2056 err
= mpage_map_one_extent(handle
, mpd
);
2058 struct super_block
*sb
= inode
->i_sb
;
2060 if (EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)
2061 goto invalidate_dirty_pages
;
2063 * Let the uper layers retry transient errors.
2064 * In the case of ENOSPC, if ext4_count_free_blocks()
2065 * is non-zero, a commit should free up blocks.
2067 if ((err
== -ENOMEM
) ||
2068 (err
== -ENOSPC
&& ext4_count_free_clusters(sb
))) {
2070 goto update_disksize
;
2073 ext4_msg(sb
, KERN_CRIT
,
2074 "Delayed block allocation failed for "
2075 "inode %lu at logical offset %llu with"
2076 " max blocks %u with error %d",
2078 (unsigned long long)map
->m_lblk
,
2079 (unsigned)map
->m_len
, -err
);
2080 ext4_msg(sb
, KERN_CRIT
,
2081 "This should not happen!! Data will "
2084 ext4_print_free_blocks(inode
);
2085 invalidate_dirty_pages
:
2086 *give_up_on_write
= true;
2091 * Update buffer state, submit mapped pages, and get us new
2094 err
= mpage_map_and_submit_buffers(mpd
);
2096 goto update_disksize
;
2097 } while (map
->m_len
);
2101 * Update on-disk size after IO is submitted. Races with
2102 * truncate are avoided by checking i_size under i_data_sem.
2104 disksize
= ((loff_t
)mpd
->first_page
) << PAGE_CACHE_SHIFT
;
2105 if (disksize
> EXT4_I(inode
)->i_disksize
) {
2109 down_write(&EXT4_I(inode
)->i_data_sem
);
2110 i_size
= i_size_read(inode
);
2111 if (disksize
> i_size
)
2113 if (disksize
> EXT4_I(inode
)->i_disksize
)
2114 EXT4_I(inode
)->i_disksize
= disksize
;
2115 err2
= ext4_mark_inode_dirty(handle
, inode
);
2116 up_write(&EXT4_I(inode
)->i_data_sem
);
2118 ext4_error(inode
->i_sb
,
2119 "Failed to mark inode %lu dirty",
2128 * Calculate the total number of credits to reserve for one writepages
2129 * iteration. This is called from ext4_writepages(). We map an extent of
2130 * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
2131 * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
2132 * bpp - 1 blocks in bpp different extents.
2134 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2136 int bpp
= ext4_journal_blocks_per_page(inode
);
2138 return ext4_meta_trans_blocks(inode
,
2139 MAX_WRITEPAGES_EXTENT_LEN
+ bpp
- 1, bpp
);
2143 * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
2144 * and underlying extent to map
2146 * @mpd - where to look for pages
2148 * Walk dirty pages in the mapping. If they are fully mapped, submit them for
2149 * IO immediately. When we find a page which isn't mapped we start accumulating
2150 * extent of buffers underlying these pages that needs mapping (formed by
2151 * either delayed or unwritten buffers). We also lock the pages containing
2152 * these buffers. The extent found is returned in @mpd structure (starting at
2153 * mpd->lblk with length mpd->len blocks).
2155 * Note that this function can attach bios to one io_end structure which are
2156 * neither logically nor physically contiguous. Although it may seem as an
2157 * unnecessary complication, it is actually inevitable in blocksize < pagesize
2158 * case as we need to track IO to all buffers underlying a page in one io_end.
2160 static int mpage_prepare_extent_to_map(struct mpage_da_data
*mpd
)
2162 struct address_space
*mapping
= mpd
->inode
->i_mapping
;
2163 struct pagevec pvec
;
2164 unsigned int nr_pages
;
2165 long left
= mpd
->wbc
->nr_to_write
;
2166 pgoff_t index
= mpd
->first_page
;
2167 pgoff_t end
= mpd
->last_page
;
2170 int blkbits
= mpd
->inode
->i_blkbits
;
2172 struct buffer_head
*head
;
2174 if (mpd
->wbc
->sync_mode
== WB_SYNC_ALL
|| mpd
->wbc
->tagged_writepages
)
2175 tag
= PAGECACHE_TAG_TOWRITE
;
2177 tag
= PAGECACHE_TAG_DIRTY
;
2179 pagevec_init(&pvec
, 0);
2181 mpd
->next_page
= index
;
2182 while (index
<= end
) {
2183 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2184 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2188 for (i
= 0; i
< nr_pages
; i
++) {
2189 struct page
*page
= pvec
.pages
[i
];
2192 * At this point, the page may be truncated or
2193 * invalidated (changing page->mapping to NULL), or
2194 * even swizzled back from swapper_space to tmpfs file
2195 * mapping. However, page->index will not change
2196 * because we have a reference on the page.
2198 if (page
->index
> end
)
2202 * Accumulated enough dirty pages? This doesn't apply
2203 * to WB_SYNC_ALL mode. For integrity sync we have to
2204 * keep going because someone may be concurrently
2205 * dirtying pages, and we might have synced a lot of
2206 * newly appeared dirty pages, but have not synced all
2207 * of the old dirty pages.
2209 if (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
&& left
<= 0)
2212 /* If we can't merge this page, we are done. */
2213 if (mpd
->map
.m_len
> 0 && mpd
->next_page
!= page
->index
)
2218 * If the page is no longer dirty, or its mapping no
2219 * longer corresponds to inode we are writing (which
2220 * means it has been truncated or invalidated), or the
2221 * page is already under writeback and we are not doing
2222 * a data integrity writeback, skip the page
2224 if (!PageDirty(page
) ||
2225 (PageWriteback(page
) &&
2226 (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2227 unlikely(page
->mapping
!= mapping
)) {
2232 wait_on_page_writeback(page
);
2233 BUG_ON(PageWriteback(page
));
2235 if (mpd
->map
.m_len
== 0)
2236 mpd
->first_page
= page
->index
;
2237 mpd
->next_page
= page
->index
+ 1;
2238 /* Add all dirty buffers to mpd */
2239 lblk
= ((ext4_lblk_t
)page
->index
) <<
2240 (PAGE_CACHE_SHIFT
- blkbits
);
2241 head
= page_buffers(page
);
2242 err
= mpage_process_page_bufs(mpd
, head
, head
, lblk
);
2248 pagevec_release(&pvec
);
2253 pagevec_release(&pvec
);
2257 static int __writepage(struct page
*page
, struct writeback_control
*wbc
,
2260 struct address_space
*mapping
= data
;
2261 int ret
= ext4_writepage(page
, wbc
);
2262 mapping_set_error(mapping
, ret
);
2266 static int ext4_writepages(struct address_space
*mapping
,
2267 struct writeback_control
*wbc
)
2269 pgoff_t writeback_index
= 0;
2270 long nr_to_write
= wbc
->nr_to_write
;
2271 int range_whole
= 0;
2273 handle_t
*handle
= NULL
;
2274 struct mpage_da_data mpd
;
2275 struct inode
*inode
= mapping
->host
;
2276 int needed_blocks
, rsv_blocks
= 0, ret
= 0;
2277 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2279 struct blk_plug plug
;
2280 bool give_up_on_write
= false;
2282 trace_ext4_writepages(inode
, wbc
);
2285 * No pages to write? This is mainly a kludge to avoid starting
2286 * a transaction for special inodes like journal inode on last iput()
2287 * because that could violate lock ordering on umount
2289 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2290 goto out_writepages
;
2292 if (ext4_should_journal_data(inode
)) {
2293 struct blk_plug plug
;
2295 blk_start_plug(&plug
);
2296 ret
= write_cache_pages(mapping
, wbc
, __writepage
, mapping
);
2297 blk_finish_plug(&plug
);
2298 goto out_writepages
;
2302 * If the filesystem has aborted, it is read-only, so return
2303 * right away instead of dumping stack traces later on that
2304 * will obscure the real source of the problem. We test
2305 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2306 * the latter could be true if the filesystem is mounted
2307 * read-only, and in that case, ext4_writepages should
2308 * *never* be called, so if that ever happens, we would want
2311 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
2313 goto out_writepages
;
2316 if (ext4_should_dioread_nolock(inode
)) {
2318 * We may need to convert up to one extent per block in
2319 * the page and we may dirty the inode.
2321 rsv_blocks
= 1 + (PAGE_CACHE_SIZE
>> inode
->i_blkbits
);
2325 * If we have inline data and arrive here, it means that
2326 * we will soon create the block for the 1st page, so
2327 * we'd better clear the inline data here.
2329 if (ext4_has_inline_data(inode
)) {
2330 /* Just inode will be modified... */
2331 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
2332 if (IS_ERR(handle
)) {
2333 ret
= PTR_ERR(handle
);
2334 goto out_writepages
;
2336 BUG_ON(ext4_test_inode_state(inode
,
2337 EXT4_STATE_MAY_INLINE_DATA
));
2338 ext4_destroy_inline_data(handle
, inode
);
2339 ext4_journal_stop(handle
);
2342 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2345 if (wbc
->range_cyclic
) {
2346 writeback_index
= mapping
->writeback_index
;
2347 if (writeback_index
)
2349 mpd
.first_page
= writeback_index
;
2352 mpd
.first_page
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2353 mpd
.last_page
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2358 ext4_io_submit_init(&mpd
.io_submit
, wbc
);
2360 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2361 tag_pages_for_writeback(mapping
, mpd
.first_page
, mpd
.last_page
);
2363 blk_start_plug(&plug
);
2364 while (!done
&& mpd
.first_page
<= mpd
.last_page
) {
2365 /* For each extent of pages we use new io_end */
2366 mpd
.io_submit
.io_end
= ext4_init_io_end(inode
, GFP_KERNEL
);
2367 if (!mpd
.io_submit
.io_end
) {
2373 * We have two constraints: We find one extent to map and we
2374 * must always write out whole page (makes a difference when
2375 * blocksize < pagesize) so that we don't block on IO when we
2376 * try to write out the rest of the page. Journalled mode is
2377 * not supported by delalloc.
2379 BUG_ON(ext4_should_journal_data(inode
));
2380 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2382 /* start a new transaction */
2383 handle
= ext4_journal_start_with_reserve(inode
,
2384 EXT4_HT_WRITE_PAGE
, needed_blocks
, rsv_blocks
);
2385 if (IS_ERR(handle
)) {
2386 ret
= PTR_ERR(handle
);
2387 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2388 "%ld pages, ino %lu; err %d", __func__
,
2389 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2390 /* Release allocated io_end */
2391 ext4_put_io_end(mpd
.io_submit
.io_end
);
2395 trace_ext4_da_write_pages(inode
, mpd
.first_page
, mpd
.wbc
);
2396 ret
= mpage_prepare_extent_to_map(&mpd
);
2399 ret
= mpage_map_and_submit_extent(handle
, &mpd
,
2403 * We scanned the whole range (or exhausted
2404 * nr_to_write), submitted what was mapped and
2405 * didn't find anything needing mapping. We are
2411 ext4_journal_stop(handle
);
2412 /* Submit prepared bio */
2413 ext4_io_submit(&mpd
.io_submit
);
2414 /* Unlock pages we didn't use */
2415 mpage_release_unused_pages(&mpd
, give_up_on_write
);
2416 /* Drop our io_end reference we got from init */
2417 ext4_put_io_end(mpd
.io_submit
.io_end
);
2419 if (ret
== -ENOSPC
&& sbi
->s_journal
) {
2421 * Commit the transaction which would
2422 * free blocks released in the transaction
2425 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2429 /* Fatal error - ENOMEM, EIO... */
2433 blk_finish_plug(&plug
);
2434 if (!ret
&& !cycled
&& wbc
->nr_to_write
> 0) {
2436 mpd
.last_page
= writeback_index
- 1;
2442 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2444 * Set the writeback_index so that range_cyclic
2445 * mode will write it back later
2447 mapping
->writeback_index
= mpd
.first_page
;
2450 trace_ext4_writepages_result(inode
, wbc
, ret
,
2451 nr_to_write
- wbc
->nr_to_write
);
2455 static int ext4_nonda_switch(struct super_block
*sb
)
2457 s64 free_clusters
, dirty_clusters
;
2458 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2461 * switch to non delalloc mode if we are running low
2462 * on free block. The free block accounting via percpu
2463 * counters can get slightly wrong with percpu_counter_batch getting
2464 * accumulated on each CPU without updating global counters
2465 * Delalloc need an accurate free block accounting. So switch
2466 * to non delalloc when we are near to error range.
2469 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2471 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2473 * Start pushing delalloc when 1/2 of free blocks are dirty.
2475 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2476 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2478 if (2 * free_clusters
< 3 * dirty_clusters
||
2479 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2481 * free block count is less than 150% of dirty blocks
2482 * or free blocks is less than watermark
2489 /* We always reserve for an inode update; the superblock could be there too */
2490 static int ext4_da_write_credits(struct inode
*inode
, loff_t pos
, unsigned len
)
2492 if (likely(EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
2493 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
)))
2496 if (pos
+ len
<= 0x7fffffffULL
)
2499 /* We might need to update the superblock to set LARGE_FILE */
2503 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2504 loff_t pos
, unsigned len
, unsigned flags
,
2505 struct page
**pagep
, void **fsdata
)
2507 int ret
, retries
= 0;
2510 struct inode
*inode
= mapping
->host
;
2513 index
= pos
>> PAGE_CACHE_SHIFT
;
2515 if (ext4_nonda_switch(inode
->i_sb
)) {
2516 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2517 return ext4_write_begin(file
, mapping
, pos
,
2518 len
, flags
, pagep
, fsdata
);
2520 *fsdata
= (void *)0;
2521 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2523 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2524 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2534 * grab_cache_page_write_begin() can take a long time if the
2535 * system is thrashing due to memory pressure, or if the page
2536 * is being written back. So grab it first before we start
2537 * the transaction handle. This also allows us to allocate
2538 * the page (if needed) without using GFP_NOFS.
2541 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2547 * With delayed allocation, we don't log the i_disksize update
2548 * if there is delayed block allocation. But we still need
2549 * to journalling the i_disksize update if writes to the end
2550 * of file which has an already mapped buffer.
2553 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2554 ext4_da_write_credits(inode
, pos
, len
));
2555 if (IS_ERR(handle
)) {
2556 page_cache_release(page
);
2557 return PTR_ERR(handle
);
2561 if (page
->mapping
!= mapping
) {
2562 /* The page got truncated from under us */
2564 page_cache_release(page
);
2565 ext4_journal_stop(handle
);
2568 /* In case writeback began while the page was unlocked */
2569 wait_for_stable_page(page
);
2571 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2574 ext4_journal_stop(handle
);
2576 * block_write_begin may have instantiated a few blocks
2577 * outside i_size. Trim these off again. Don't need
2578 * i_size_read because we hold i_mutex.
2580 if (pos
+ len
> inode
->i_size
)
2581 ext4_truncate_failed_write(inode
);
2583 if (ret
== -ENOSPC
&&
2584 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2587 page_cache_release(page
);
2596 * Check if we should update i_disksize
2597 * when write to the end of file but not require block allocation
2599 static int ext4_da_should_update_i_disksize(struct page
*page
,
2600 unsigned long offset
)
2602 struct buffer_head
*bh
;
2603 struct inode
*inode
= page
->mapping
->host
;
2607 bh
= page_buffers(page
);
2608 idx
= offset
>> inode
->i_blkbits
;
2610 for (i
= 0; i
< idx
; i
++)
2611 bh
= bh
->b_this_page
;
2613 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2618 static int ext4_da_write_end(struct file
*file
,
2619 struct address_space
*mapping
,
2620 loff_t pos
, unsigned len
, unsigned copied
,
2621 struct page
*page
, void *fsdata
)
2623 struct inode
*inode
= mapping
->host
;
2625 handle_t
*handle
= ext4_journal_current_handle();
2627 unsigned long start
, end
;
2628 int write_mode
= (int)(unsigned long)fsdata
;
2630 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2631 return ext4_write_end(file
, mapping
, pos
,
2632 len
, copied
, page
, fsdata
);
2634 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2635 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2636 end
= start
+ copied
- 1;
2639 * generic_write_end() will run mark_inode_dirty() if i_size
2640 * changes. So let's piggyback the i_disksize mark_inode_dirty
2643 new_i_size
= pos
+ copied
;
2644 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2645 if (ext4_has_inline_data(inode
) ||
2646 ext4_da_should_update_i_disksize(page
, end
)) {
2647 ext4_update_i_disksize(inode
, new_i_size
);
2648 /* We need to mark inode dirty even if
2649 * new_i_size is less that inode->i_size
2650 * bu greater than i_disksize.(hint delalloc)
2652 ext4_mark_inode_dirty(handle
, inode
);
2656 if (write_mode
!= CONVERT_INLINE_DATA
&&
2657 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2658 ext4_has_inline_data(inode
))
2659 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2662 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2668 ret2
= ext4_journal_stop(handle
);
2672 return ret
? ret
: copied
;
2675 static void ext4_da_invalidatepage(struct page
*page
, unsigned int offset
,
2676 unsigned int length
)
2679 * Drop reserved blocks
2681 BUG_ON(!PageLocked(page
));
2682 if (!page_has_buffers(page
))
2685 ext4_da_page_release_reservation(page
, offset
, length
);
2688 ext4_invalidatepage(page
, offset
, length
);
2694 * Force all delayed allocation blocks to be allocated for a given inode.
2696 int ext4_alloc_da_blocks(struct inode
*inode
)
2698 trace_ext4_alloc_da_blocks(inode
);
2700 if (!EXT4_I(inode
)->i_reserved_data_blocks
)
2704 * We do something simple for now. The filemap_flush() will
2705 * also start triggering a write of the data blocks, which is
2706 * not strictly speaking necessary (and for users of
2707 * laptop_mode, not even desirable). However, to do otherwise
2708 * would require replicating code paths in:
2710 * ext4_writepages() ->
2711 * write_cache_pages() ---> (via passed in callback function)
2712 * __mpage_da_writepage() -->
2713 * mpage_add_bh_to_extent()
2714 * mpage_da_map_blocks()
2716 * The problem is that write_cache_pages(), located in
2717 * mm/page-writeback.c, marks pages clean in preparation for
2718 * doing I/O, which is not desirable if we're not planning on
2721 * We could call write_cache_pages(), and then redirty all of
2722 * the pages by calling redirty_page_for_writepage() but that
2723 * would be ugly in the extreme. So instead we would need to
2724 * replicate parts of the code in the above functions,
2725 * simplifying them because we wouldn't actually intend to
2726 * write out the pages, but rather only collect contiguous
2727 * logical block extents, call the multi-block allocator, and
2728 * then update the buffer heads with the block allocations.
2730 * For now, though, we'll cheat by calling filemap_flush(),
2731 * which will map the blocks, and start the I/O, but not
2732 * actually wait for the I/O to complete.
2734 return filemap_flush(inode
->i_mapping
);
2738 * bmap() is special. It gets used by applications such as lilo and by
2739 * the swapper to find the on-disk block of a specific piece of data.
2741 * Naturally, this is dangerous if the block concerned is still in the
2742 * journal. If somebody makes a swapfile on an ext4 data-journaling
2743 * filesystem and enables swap, then they may get a nasty shock when the
2744 * data getting swapped to that swapfile suddenly gets overwritten by
2745 * the original zero's written out previously to the journal and
2746 * awaiting writeback in the kernel's buffer cache.
2748 * So, if we see any bmap calls here on a modified, data-journaled file,
2749 * take extra steps to flush any blocks which might be in the cache.
2751 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2753 struct inode
*inode
= mapping
->host
;
2758 * We can get here for an inline file via the FIBMAP ioctl
2760 if (ext4_has_inline_data(inode
))
2763 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2764 test_opt(inode
->i_sb
, DELALLOC
)) {
2766 * With delalloc we want to sync the file
2767 * so that we can make sure we allocate
2770 filemap_write_and_wait(mapping
);
2773 if (EXT4_JOURNAL(inode
) &&
2774 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2776 * This is a REALLY heavyweight approach, but the use of
2777 * bmap on dirty files is expected to be extremely rare:
2778 * only if we run lilo or swapon on a freshly made file
2779 * do we expect this to happen.
2781 * (bmap requires CAP_SYS_RAWIO so this does not
2782 * represent an unprivileged user DOS attack --- we'd be
2783 * in trouble if mortal users could trigger this path at
2786 * NB. EXT4_STATE_JDATA is not set on files other than
2787 * regular files. If somebody wants to bmap a directory
2788 * or symlink and gets confused because the buffer
2789 * hasn't yet been flushed to disk, they deserve
2790 * everything they get.
2793 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2794 journal
= EXT4_JOURNAL(inode
);
2795 jbd2_journal_lock_updates(journal
);
2796 err
= jbd2_journal_flush(journal
);
2797 jbd2_journal_unlock_updates(journal
);
2803 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2806 static int ext4_readpage(struct file
*file
, struct page
*page
)
2809 struct inode
*inode
= page
->mapping
->host
;
2811 trace_ext4_readpage(page
);
2813 if (ext4_has_inline_data(inode
))
2814 ret
= ext4_readpage_inline(inode
, page
);
2817 return mpage_readpage(page
, ext4_get_block
);
2823 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2824 struct list_head
*pages
, unsigned nr_pages
)
2826 struct inode
*inode
= mapping
->host
;
2828 /* If the file has inline data, no need to do readpages. */
2829 if (ext4_has_inline_data(inode
))
2832 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
2835 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
2836 unsigned int length
)
2838 trace_ext4_invalidatepage(page
, offset
, length
);
2840 /* No journalling happens on data buffers when this function is used */
2841 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
2843 block_invalidatepage(page
, offset
, length
);
2846 static int __ext4_journalled_invalidatepage(struct page
*page
,
2847 unsigned int offset
,
2848 unsigned int length
)
2850 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2852 trace_ext4_journalled_invalidatepage(page
, offset
, length
);
2855 * If it's a full truncate we just forget about the pending dirtying
2857 if (offset
== 0 && length
== PAGE_CACHE_SIZE
)
2858 ClearPageChecked(page
);
2860 return jbd2_journal_invalidatepage(journal
, page
, offset
, length
);
2863 /* Wrapper for aops... */
2864 static void ext4_journalled_invalidatepage(struct page
*page
,
2865 unsigned int offset
,
2866 unsigned int length
)
2868 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
, length
) < 0);
2871 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
2873 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2875 trace_ext4_releasepage(page
);
2877 /* Page has dirty journalled data -> cannot release */
2878 if (PageChecked(page
))
2881 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
2883 return try_to_free_buffers(page
);
2887 * ext4_get_block used when preparing for a DIO write or buffer write.
2888 * We allocate an uinitialized extent if blocks haven't been allocated.
2889 * The extent will be converted to initialized after the IO is complete.
2891 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
2892 struct buffer_head
*bh_result
, int create
)
2894 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
2895 inode
->i_ino
, create
);
2896 return _ext4_get_block(inode
, iblock
, bh_result
,
2897 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
2900 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
2901 struct buffer_head
*bh_result
, int create
)
2903 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
2904 inode
->i_ino
, create
);
2905 return _ext4_get_block(inode
, iblock
, bh_result
,
2906 EXT4_GET_BLOCKS_NO_LOCK
);
2909 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
2910 ssize_t size
, void *private)
2912 ext4_io_end_t
*io_end
= iocb
->private;
2914 /* if not async direct IO just return */
2918 ext_debug("ext4_end_io_dio(): io_end 0x%p "
2919 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
2920 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
2923 iocb
->private = NULL
;
2924 io_end
->offset
= offset
;
2925 io_end
->size
= size
;
2926 ext4_put_io_end(io_end
);
2930 * For ext4 extent files, ext4 will do direct-io write to holes,
2931 * preallocated extents, and those write extend the file, no need to
2932 * fall back to buffered IO.
2934 * For holes, we fallocate those blocks, mark them as unwritten
2935 * If those blocks were preallocated, we mark sure they are split, but
2936 * still keep the range to write as unwritten.
2938 * The unwritten extents will be converted to written when DIO is completed.
2939 * For async direct IO, since the IO may still pending when return, we
2940 * set up an end_io call back function, which will do the conversion
2941 * when async direct IO completed.
2943 * If the O_DIRECT write will extend the file then add this inode to the
2944 * orphan list. So recovery will truncate it back to the original size
2945 * if the machine crashes during the write.
2948 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
2949 struct iov_iter
*iter
, loff_t offset
)
2951 struct file
*file
= iocb
->ki_filp
;
2952 struct inode
*inode
= file
->f_mapping
->host
;
2954 size_t count
= iov_iter_count(iter
);
2956 get_block_t
*get_block_func
= NULL
;
2958 loff_t final_size
= offset
+ count
;
2959 ext4_io_end_t
*io_end
= NULL
;
2961 /* Use the old path for reads and writes beyond i_size. */
2962 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
2963 return ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
2965 BUG_ON(iocb
->private == NULL
);
2968 * Make all waiters for direct IO properly wait also for extent
2969 * conversion. This also disallows race between truncate() and
2970 * overwrite DIO as i_dio_count needs to be incremented under i_mutex.
2973 atomic_inc(&inode
->i_dio_count
);
2975 /* If we do a overwrite dio, i_mutex locking can be released */
2976 overwrite
= *((int *)iocb
->private);
2979 down_read(&EXT4_I(inode
)->i_data_sem
);
2980 mutex_unlock(&inode
->i_mutex
);
2984 * We could direct write to holes and fallocate.
2986 * Allocated blocks to fill the hole are marked as
2987 * unwritten to prevent parallel buffered read to expose
2988 * the stale data before DIO complete the data IO.
2990 * As to previously fallocated extents, ext4 get_block will
2991 * just simply mark the buffer mapped but still keep the
2992 * extents unwritten.
2994 * For non AIO case, we will convert those unwritten extents
2995 * to written after return back from blockdev_direct_IO.
2997 * For async DIO, the conversion needs to be deferred when the
2998 * IO is completed. The ext4 end_io callback function will be
2999 * called to take care of the conversion work. Here for async
3000 * case, we allocate an io_end structure to hook to the iocb.
3002 iocb
->private = NULL
;
3003 ext4_inode_aio_set(inode
, NULL
);
3004 if (!is_sync_kiocb(iocb
)) {
3005 io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3011 * Grab reference for DIO. Will be dropped in ext4_end_io_dio()
3013 iocb
->private = ext4_get_io_end(io_end
);
3015 * we save the io structure for current async direct
3016 * IO, so that later ext4_map_blocks() could flag the
3017 * io structure whether there is a unwritten extents
3018 * needs to be converted when IO is completed.
3020 ext4_inode_aio_set(inode
, io_end
);
3024 get_block_func
= ext4_get_block_write_nolock
;
3026 get_block_func
= ext4_get_block_write
;
3027 dio_flags
= DIO_LOCKING
;
3030 ret
= dax_do_io(rw
, iocb
, inode
, iter
, offset
, get_block_func
,
3031 ext4_end_io_dio
, dio_flags
);
3033 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3034 inode
->i_sb
->s_bdev
, iter
, offset
,
3036 ext4_end_io_dio
, NULL
, dio_flags
);
3039 * Put our reference to io_end. This can free the io_end structure e.g.
3040 * in sync IO case or in case of error. It can even perform extent
3041 * conversion if all bios we submitted finished before we got here.
3042 * Note that in that case iocb->private can be already set to NULL
3046 ext4_inode_aio_set(inode
, NULL
);
3047 ext4_put_io_end(io_end
);
3049 * When no IO was submitted ext4_end_io_dio() was not
3050 * called so we have to put iocb's reference.
3052 if (ret
<= 0 && ret
!= -EIOCBQUEUED
&& iocb
->private) {
3053 WARN_ON(iocb
->private != io_end
);
3054 WARN_ON(io_end
->flag
& EXT4_IO_END_UNWRITTEN
);
3055 ext4_put_io_end(io_end
);
3056 iocb
->private = NULL
;
3059 if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3060 EXT4_STATE_DIO_UNWRITTEN
)) {
3063 * for non AIO case, since the IO is already
3064 * completed, we could do the conversion right here
3066 err
= ext4_convert_unwritten_extents(NULL
, inode
,
3070 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3075 inode_dio_done(inode
);
3076 /* take i_mutex locking again if we do a ovewrite dio */
3078 up_read(&EXT4_I(inode
)->i_data_sem
);
3079 mutex_lock(&inode
->i_mutex
);
3085 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3086 struct iov_iter
*iter
, loff_t offset
)
3088 struct file
*file
= iocb
->ki_filp
;
3089 struct inode
*inode
= file
->f_mapping
->host
;
3090 size_t count
= iov_iter_count(iter
);
3094 * If we are doing data journalling we don't support O_DIRECT
3096 if (ext4_should_journal_data(inode
))
3099 /* Let buffer I/O handle the inline data case. */
3100 if (ext4_has_inline_data(inode
))
3103 trace_ext4_direct_IO_enter(inode
, offset
, count
, rw
);
3104 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3105 ret
= ext4_ext_direct_IO(rw
, iocb
, iter
, offset
);
3107 ret
= ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
3108 trace_ext4_direct_IO_exit(inode
, offset
, count
, rw
, ret
);
3113 * Pages can be marked dirty completely asynchronously from ext4's journalling
3114 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3115 * much here because ->set_page_dirty is called under VFS locks. The page is
3116 * not necessarily locked.
3118 * We cannot just dirty the page and leave attached buffers clean, because the
3119 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3120 * or jbddirty because all the journalling code will explode.
3122 * So what we do is to mark the page "pending dirty" and next time writepage
3123 * is called, propagate that into the buffers appropriately.
3125 static int ext4_journalled_set_page_dirty(struct page
*page
)
3127 SetPageChecked(page
);
3128 return __set_page_dirty_nobuffers(page
);
3131 static const struct address_space_operations ext4_aops
= {
3132 .readpage
= ext4_readpage
,
3133 .readpages
= ext4_readpages
,
3134 .writepage
= ext4_writepage
,
3135 .writepages
= ext4_writepages
,
3136 .write_begin
= ext4_write_begin
,
3137 .write_end
= ext4_write_end
,
3139 .invalidatepage
= ext4_invalidatepage
,
3140 .releasepage
= ext4_releasepage
,
3141 .direct_IO
= ext4_direct_IO
,
3142 .migratepage
= buffer_migrate_page
,
3143 .is_partially_uptodate
= block_is_partially_uptodate
,
3144 .error_remove_page
= generic_error_remove_page
,
3147 static const struct address_space_operations ext4_journalled_aops
= {
3148 .readpage
= ext4_readpage
,
3149 .readpages
= ext4_readpages
,
3150 .writepage
= ext4_writepage
,
3151 .writepages
= ext4_writepages
,
3152 .write_begin
= ext4_write_begin
,
3153 .write_end
= ext4_journalled_write_end
,
3154 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3156 .invalidatepage
= ext4_journalled_invalidatepage
,
3157 .releasepage
= ext4_releasepage
,
3158 .direct_IO
= ext4_direct_IO
,
3159 .is_partially_uptodate
= block_is_partially_uptodate
,
3160 .error_remove_page
= generic_error_remove_page
,
3163 static const struct address_space_operations ext4_da_aops
= {
3164 .readpage
= ext4_readpage
,
3165 .readpages
= ext4_readpages
,
3166 .writepage
= ext4_writepage
,
3167 .writepages
= ext4_writepages
,
3168 .write_begin
= ext4_da_write_begin
,
3169 .write_end
= ext4_da_write_end
,
3171 .invalidatepage
= ext4_da_invalidatepage
,
3172 .releasepage
= ext4_releasepage
,
3173 .direct_IO
= ext4_direct_IO
,
3174 .migratepage
= buffer_migrate_page
,
3175 .is_partially_uptodate
= block_is_partially_uptodate
,
3176 .error_remove_page
= generic_error_remove_page
,
3179 void ext4_set_aops(struct inode
*inode
)
3181 switch (ext4_inode_journal_mode(inode
)) {
3182 case EXT4_INODE_ORDERED_DATA_MODE
:
3183 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3185 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3186 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3188 case EXT4_INODE_JOURNAL_DATA_MODE
:
3189 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3194 if (test_opt(inode
->i_sb
, DELALLOC
))
3195 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3197 inode
->i_mapping
->a_ops
= &ext4_aops
;
3200 static int __ext4_block_zero_page_range(handle_t
*handle
,
3201 struct address_space
*mapping
, loff_t from
, loff_t length
)
3203 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3204 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3205 unsigned blocksize
, pos
;
3207 struct inode
*inode
= mapping
->host
;
3208 struct buffer_head
*bh
;
3212 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3213 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3217 blocksize
= inode
->i_sb
->s_blocksize
;
3219 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3221 if (!page_has_buffers(page
))
3222 create_empty_buffers(page
, blocksize
, 0);
3224 /* Find the buffer that contains "offset" */
3225 bh
= page_buffers(page
);
3227 while (offset
>= pos
) {
3228 bh
= bh
->b_this_page
;
3232 if (buffer_freed(bh
)) {
3233 BUFFER_TRACE(bh
, "freed: skip");
3236 if (!buffer_mapped(bh
)) {
3237 BUFFER_TRACE(bh
, "unmapped");
3238 ext4_get_block(inode
, iblock
, bh
, 0);
3239 /* unmapped? It's a hole - nothing to do */
3240 if (!buffer_mapped(bh
)) {
3241 BUFFER_TRACE(bh
, "still unmapped");
3246 /* Ok, it's mapped. Make sure it's up-to-date */
3247 if (PageUptodate(page
))
3248 set_buffer_uptodate(bh
);
3250 if (!buffer_uptodate(bh
)) {
3252 ll_rw_block(READ
, 1, &bh
);
3254 /* Uhhuh. Read error. Complain and punt. */
3255 if (!buffer_uptodate(bh
))
3258 if (ext4_should_journal_data(inode
)) {
3259 BUFFER_TRACE(bh
, "get write access");
3260 err
= ext4_journal_get_write_access(handle
, bh
);
3264 zero_user(page
, offset
, length
);
3265 BUFFER_TRACE(bh
, "zeroed end of block");
3267 if (ext4_should_journal_data(inode
)) {
3268 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3271 mark_buffer_dirty(bh
);
3272 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
))
3273 err
= ext4_jbd2_file_inode(handle
, inode
);
3278 page_cache_release(page
);
3283 * ext4_block_zero_page_range() zeros out a mapping of length 'length'
3284 * starting from file offset 'from'. The range to be zero'd must
3285 * be contained with in one block. If the specified range exceeds
3286 * the end of the block it will be shortened to end of the block
3287 * that cooresponds to 'from'
3289 static int ext4_block_zero_page_range(handle_t
*handle
,
3290 struct address_space
*mapping
, loff_t from
, loff_t length
)
3292 struct inode
*inode
= mapping
->host
;
3293 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3294 unsigned blocksize
= inode
->i_sb
->s_blocksize
;
3295 unsigned max
= blocksize
- (offset
& (blocksize
- 1));
3298 * correct length if it does not fall between
3299 * 'from' and the end of the block
3301 if (length
> max
|| length
< 0)
3305 return dax_zero_page_range(inode
, from
, length
, ext4_get_block
);
3306 return __ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3310 * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
3311 * up to the end of the block which corresponds to `from'.
3312 * This required during truncate. We need to physically zero the tail end
3313 * of that block so it doesn't yield old data if the file is later grown.
3315 static int ext4_block_truncate_page(handle_t
*handle
,
3316 struct address_space
*mapping
, loff_t from
)
3318 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3321 struct inode
*inode
= mapping
->host
;
3323 blocksize
= inode
->i_sb
->s_blocksize
;
3324 length
= blocksize
- (offset
& (blocksize
- 1));
3326 return ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3329 int ext4_zero_partial_blocks(handle_t
*handle
, struct inode
*inode
,
3330 loff_t lstart
, loff_t length
)
3332 struct super_block
*sb
= inode
->i_sb
;
3333 struct address_space
*mapping
= inode
->i_mapping
;
3334 unsigned partial_start
, partial_end
;
3335 ext4_fsblk_t start
, end
;
3336 loff_t byte_end
= (lstart
+ length
- 1);
3339 partial_start
= lstart
& (sb
->s_blocksize
- 1);
3340 partial_end
= byte_end
& (sb
->s_blocksize
- 1);
3342 start
= lstart
>> sb
->s_blocksize_bits
;
3343 end
= byte_end
>> sb
->s_blocksize_bits
;
3345 /* Handle partial zero within the single block */
3347 (partial_start
|| (partial_end
!= sb
->s_blocksize
- 1))) {
3348 err
= ext4_block_zero_page_range(handle
, mapping
,
3352 /* Handle partial zero out on the start of the range */
3353 if (partial_start
) {
3354 err
= ext4_block_zero_page_range(handle
, mapping
,
3355 lstart
, sb
->s_blocksize
);
3359 /* Handle partial zero out on the end of the range */
3360 if (partial_end
!= sb
->s_blocksize
- 1)
3361 err
= ext4_block_zero_page_range(handle
, mapping
,
3362 byte_end
- partial_end
,
3367 int ext4_can_truncate(struct inode
*inode
)
3369 if (S_ISREG(inode
->i_mode
))
3371 if (S_ISDIR(inode
->i_mode
))
3373 if (S_ISLNK(inode
->i_mode
))
3374 return !ext4_inode_is_fast_symlink(inode
);
3379 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3380 * associated with the given offset and length
3382 * @inode: File inode
3383 * @offset: The offset where the hole will begin
3384 * @len: The length of the hole
3386 * Returns: 0 on success or negative on failure
3389 int ext4_punch_hole(struct inode
*inode
, loff_t offset
, loff_t length
)
3391 struct super_block
*sb
= inode
->i_sb
;
3392 ext4_lblk_t first_block
, stop_block
;
3393 struct address_space
*mapping
= inode
->i_mapping
;
3394 loff_t first_block_offset
, last_block_offset
;
3396 unsigned int credits
;
3399 if (!S_ISREG(inode
->i_mode
))
3402 trace_ext4_punch_hole(inode
, offset
, length
, 0);
3405 * Write out all dirty pages to avoid race conditions
3406 * Then release them.
3408 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3409 ret
= filemap_write_and_wait_range(mapping
, offset
,
3410 offset
+ length
- 1);
3415 mutex_lock(&inode
->i_mutex
);
3417 /* No need to punch hole beyond i_size */
3418 if (offset
>= inode
->i_size
)
3422 * If the hole extends beyond i_size, set the hole
3423 * to end after the page that contains i_size
3425 if (offset
+ length
> inode
->i_size
) {
3426 length
= inode
->i_size
+
3427 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3431 if (offset
& (sb
->s_blocksize
- 1) ||
3432 (offset
+ length
) & (sb
->s_blocksize
- 1)) {
3434 * Attach jinode to inode for jbd2 if we do any zeroing of
3437 ret
= ext4_inode_attach_jinode(inode
);
3443 first_block_offset
= round_up(offset
, sb
->s_blocksize
);
3444 last_block_offset
= round_down((offset
+ length
), sb
->s_blocksize
) - 1;
3446 /* Now release the pages and zero block aligned part of pages*/
3447 if (last_block_offset
> first_block_offset
)
3448 truncate_pagecache_range(inode
, first_block_offset
,
3451 /* Wait all existing dio workers, newcomers will block on i_mutex */
3452 ext4_inode_block_unlocked_dio(inode
);
3453 inode_dio_wait(inode
);
3455 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3456 credits
= ext4_writepage_trans_blocks(inode
);
3458 credits
= ext4_blocks_for_truncate(inode
);
3459 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3460 if (IS_ERR(handle
)) {
3461 ret
= PTR_ERR(handle
);
3462 ext4_std_error(sb
, ret
);
3466 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
,
3471 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3472 EXT4_BLOCK_SIZE_BITS(sb
);
3473 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3475 /* If there are no blocks to remove, return now */
3476 if (first_block
>= stop_block
)
3479 down_write(&EXT4_I(inode
)->i_data_sem
);
3480 ext4_discard_preallocations(inode
);
3482 ret
= ext4_es_remove_extent(inode
, first_block
,
3483 stop_block
- first_block
);
3485 up_write(&EXT4_I(inode
)->i_data_sem
);
3489 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3490 ret
= ext4_ext_remove_space(inode
, first_block
,
3493 ret
= ext4_ind_remove_space(handle
, inode
, first_block
,
3496 up_write(&EXT4_I(inode
)->i_data_sem
);
3498 ext4_handle_sync(handle
);
3500 /* Now release the pages again to reduce race window */
3501 if (last_block_offset
> first_block_offset
)
3502 truncate_pagecache_range(inode
, first_block_offset
,
3505 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3506 ext4_mark_inode_dirty(handle
, inode
);
3508 ext4_journal_stop(handle
);
3510 ext4_inode_resume_unlocked_dio(inode
);
3512 mutex_unlock(&inode
->i_mutex
);
3516 int ext4_inode_attach_jinode(struct inode
*inode
)
3518 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3519 struct jbd2_inode
*jinode
;
3521 if (ei
->jinode
|| !EXT4_SB(inode
->i_sb
)->s_journal
)
3524 jinode
= jbd2_alloc_inode(GFP_KERNEL
);
3525 spin_lock(&inode
->i_lock
);
3528 spin_unlock(&inode
->i_lock
);
3531 ei
->jinode
= jinode
;
3532 jbd2_journal_init_jbd_inode(ei
->jinode
, inode
);
3535 spin_unlock(&inode
->i_lock
);
3536 if (unlikely(jinode
!= NULL
))
3537 jbd2_free_inode(jinode
);
3544 * We block out ext4_get_block() block instantiations across the entire
3545 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3546 * simultaneously on behalf of the same inode.
3548 * As we work through the truncate and commit bits of it to the journal there
3549 * is one core, guiding principle: the file's tree must always be consistent on
3550 * disk. We must be able to restart the truncate after a crash.
3552 * The file's tree may be transiently inconsistent in memory (although it
3553 * probably isn't), but whenever we close off and commit a journal transaction,
3554 * the contents of (the filesystem + the journal) must be consistent and
3555 * restartable. It's pretty simple, really: bottom up, right to left (although
3556 * left-to-right works OK too).
3558 * Note that at recovery time, journal replay occurs *before* the restart of
3559 * truncate against the orphan inode list.
3561 * The committed inode has the new, desired i_size (which is the same as
3562 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3563 * that this inode's truncate did not complete and it will again call
3564 * ext4_truncate() to have another go. So there will be instantiated blocks
3565 * to the right of the truncation point in a crashed ext4 filesystem. But
3566 * that's fine - as long as they are linked from the inode, the post-crash
3567 * ext4_truncate() run will find them and release them.
3569 void ext4_truncate(struct inode
*inode
)
3571 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3572 unsigned int credits
;
3574 struct address_space
*mapping
= inode
->i_mapping
;
3577 * There is a possibility that we're either freeing the inode
3578 * or it's a completely new inode. In those cases we might not
3579 * have i_mutex locked because it's not necessary.
3581 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3582 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3583 trace_ext4_truncate_enter(inode
);
3585 if (!ext4_can_truncate(inode
))
3588 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3590 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3591 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3593 if (ext4_has_inline_data(inode
)) {
3596 ext4_inline_data_truncate(inode
, &has_inline
);
3601 /* If we zero-out tail of the page, we have to create jinode for jbd2 */
3602 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1)) {
3603 if (ext4_inode_attach_jinode(inode
) < 0)
3607 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3608 credits
= ext4_writepage_trans_blocks(inode
);
3610 credits
= ext4_blocks_for_truncate(inode
);
3612 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3613 if (IS_ERR(handle
)) {
3614 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3618 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1))
3619 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3622 * We add the inode to the orphan list, so that if this
3623 * truncate spans multiple transactions, and we crash, we will
3624 * resume the truncate when the filesystem recovers. It also
3625 * marks the inode dirty, to catch the new size.
3627 * Implication: the file must always be in a sane, consistent
3628 * truncatable state while each transaction commits.
3630 if (ext4_orphan_add(handle
, inode
))
3633 down_write(&EXT4_I(inode
)->i_data_sem
);
3635 ext4_discard_preallocations(inode
);
3637 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3638 ext4_ext_truncate(handle
, inode
);
3640 ext4_ind_truncate(handle
, inode
);
3642 up_write(&ei
->i_data_sem
);
3645 ext4_handle_sync(handle
);
3649 * If this was a simple ftruncate() and the file will remain alive,
3650 * then we need to clear up the orphan record which we created above.
3651 * However, if this was a real unlink then we were called by
3652 * ext4_evict_inode(), and we allow that function to clean up the
3653 * orphan info for us.
3656 ext4_orphan_del(handle
, inode
);
3658 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3659 ext4_mark_inode_dirty(handle
, inode
);
3660 ext4_journal_stop(handle
);
3662 trace_ext4_truncate_exit(inode
);
3666 * ext4_get_inode_loc returns with an extra refcount against the inode's
3667 * underlying buffer_head on success. If 'in_mem' is true, we have all
3668 * data in memory that is needed to recreate the on-disk version of this
3671 static int __ext4_get_inode_loc(struct inode
*inode
,
3672 struct ext4_iloc
*iloc
, int in_mem
)
3674 struct ext4_group_desc
*gdp
;
3675 struct buffer_head
*bh
;
3676 struct super_block
*sb
= inode
->i_sb
;
3678 int inodes_per_block
, inode_offset
;
3681 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3684 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3685 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3690 * Figure out the offset within the block group inode table
3692 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3693 inode_offset
= ((inode
->i_ino
- 1) %
3694 EXT4_INODES_PER_GROUP(sb
));
3695 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3696 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3698 bh
= sb_getblk(sb
, block
);
3701 if (!buffer_uptodate(bh
)) {
3705 * If the buffer has the write error flag, we have failed
3706 * to write out another inode in the same block. In this
3707 * case, we don't have to read the block because we may
3708 * read the old inode data successfully.
3710 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3711 set_buffer_uptodate(bh
);
3713 if (buffer_uptodate(bh
)) {
3714 /* someone brought it uptodate while we waited */
3720 * If we have all information of the inode in memory and this
3721 * is the only valid inode in the block, we need not read the
3725 struct buffer_head
*bitmap_bh
;
3728 start
= inode_offset
& ~(inodes_per_block
- 1);
3730 /* Is the inode bitmap in cache? */
3731 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3732 if (unlikely(!bitmap_bh
))
3736 * If the inode bitmap isn't in cache then the
3737 * optimisation may end up performing two reads instead
3738 * of one, so skip it.
3740 if (!buffer_uptodate(bitmap_bh
)) {
3744 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
3745 if (i
== inode_offset
)
3747 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
3751 if (i
== start
+ inodes_per_block
) {
3752 /* all other inodes are free, so skip I/O */
3753 memset(bh
->b_data
, 0, bh
->b_size
);
3754 set_buffer_uptodate(bh
);
3762 * If we need to do any I/O, try to pre-readahead extra
3763 * blocks from the inode table.
3765 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
3766 ext4_fsblk_t b
, end
, table
;
3768 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
3770 table
= ext4_inode_table(sb
, gdp
);
3771 /* s_inode_readahead_blks is always a power of 2 */
3772 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
3776 num
= EXT4_INODES_PER_GROUP(sb
);
3777 if (ext4_has_group_desc_csum(sb
))
3778 num
-= ext4_itable_unused_count(sb
, gdp
);
3779 table
+= num
/ inodes_per_block
;
3783 sb_breadahead(sb
, b
++);
3787 * There are other valid inodes in the buffer, this inode
3788 * has in-inode xattrs, or we don't have this inode in memory.
3789 * Read the block from disk.
3791 trace_ext4_load_inode(inode
);
3793 bh
->b_end_io
= end_buffer_read_sync
;
3794 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
3796 if (!buffer_uptodate(bh
)) {
3797 EXT4_ERROR_INODE_BLOCK(inode
, block
,
3798 "unable to read itable block");
3808 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
3810 /* We have all inode data except xattrs in memory here. */
3811 return __ext4_get_inode_loc(inode
, iloc
,
3812 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
3815 void ext4_set_inode_flags(struct inode
*inode
)
3817 unsigned int flags
= EXT4_I(inode
)->i_flags
;
3818 unsigned int new_fl
= 0;
3820 if (flags
& EXT4_SYNC_FL
)
3822 if (flags
& EXT4_APPEND_FL
)
3824 if (flags
& EXT4_IMMUTABLE_FL
)
3825 new_fl
|= S_IMMUTABLE
;
3826 if (flags
& EXT4_NOATIME_FL
)
3827 new_fl
|= S_NOATIME
;
3828 if (flags
& EXT4_DIRSYNC_FL
)
3829 new_fl
|= S_DIRSYNC
;
3830 if (test_opt(inode
->i_sb
, DAX
))
3832 inode_set_flags(inode
, new_fl
,
3833 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
|S_DAX
);
3836 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
3837 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
3839 unsigned int vfs_fl
;
3840 unsigned long old_fl
, new_fl
;
3843 vfs_fl
= ei
->vfs_inode
.i_flags
;
3844 old_fl
= ei
->i_flags
;
3845 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
3846 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
3848 if (vfs_fl
& S_SYNC
)
3849 new_fl
|= EXT4_SYNC_FL
;
3850 if (vfs_fl
& S_APPEND
)
3851 new_fl
|= EXT4_APPEND_FL
;
3852 if (vfs_fl
& S_IMMUTABLE
)
3853 new_fl
|= EXT4_IMMUTABLE_FL
;
3854 if (vfs_fl
& S_NOATIME
)
3855 new_fl
|= EXT4_NOATIME_FL
;
3856 if (vfs_fl
& S_DIRSYNC
)
3857 new_fl
|= EXT4_DIRSYNC_FL
;
3858 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
3861 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
3862 struct ext4_inode_info
*ei
)
3865 struct inode
*inode
= &(ei
->vfs_inode
);
3866 struct super_block
*sb
= inode
->i_sb
;
3868 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
3869 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
3870 /* we are using combined 48 bit field */
3871 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
3872 le32_to_cpu(raw_inode
->i_blocks_lo
);
3873 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
3874 /* i_blocks represent file system block size */
3875 return i_blocks
<< (inode
->i_blkbits
- 9);
3880 return le32_to_cpu(raw_inode
->i_blocks_lo
);
3884 static inline void ext4_iget_extra_inode(struct inode
*inode
,
3885 struct ext4_inode
*raw_inode
,
3886 struct ext4_inode_info
*ei
)
3888 __le32
*magic
= (void *)raw_inode
+
3889 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
3890 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
3891 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
3892 ext4_find_inline_data_nolock(inode
);
3894 EXT4_I(inode
)->i_inline_off
= 0;
3897 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
3899 struct ext4_iloc iloc
;
3900 struct ext4_inode
*raw_inode
;
3901 struct ext4_inode_info
*ei
;
3902 struct inode
*inode
;
3903 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
3909 inode
= iget_locked(sb
, ino
);
3911 return ERR_PTR(-ENOMEM
);
3912 if (!(inode
->i_state
& I_NEW
))
3918 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
3921 raw_inode
= ext4_raw_inode(&iloc
);
3923 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
3924 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
3925 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
3926 EXT4_INODE_SIZE(inode
->i_sb
)) {
3927 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
3928 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
3929 EXT4_INODE_SIZE(inode
->i_sb
));
3934 ei
->i_extra_isize
= 0;
3936 /* Precompute checksum seed for inode metadata */
3937 if (ext4_has_metadata_csum(sb
)) {
3938 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3940 __le32 inum
= cpu_to_le32(inode
->i_ino
);
3941 __le32 gen
= raw_inode
->i_generation
;
3942 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
3944 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
3948 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
3949 EXT4_ERROR_INODE(inode
, "checksum invalid");
3954 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
3955 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
3956 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
3957 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
3958 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
3959 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
3961 i_uid_write(inode
, i_uid
);
3962 i_gid_write(inode
, i_gid
);
3963 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
3965 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
3966 ei
->i_inline_off
= 0;
3967 ei
->i_dir_start_lookup
= 0;
3968 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
3969 /* We now have enough fields to check if the inode was active or not.
3970 * This is needed because nfsd might try to access dead inodes
3971 * the test is that same one that e2fsck uses
3972 * NeilBrown 1999oct15
3974 if (inode
->i_nlink
== 0) {
3975 if ((inode
->i_mode
== 0 ||
3976 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
3977 ino
!= EXT4_BOOT_LOADER_INO
) {
3978 /* this inode is deleted */
3982 /* The only unlinked inodes we let through here have
3983 * valid i_mode and are being read by the orphan
3984 * recovery code: that's fine, we're about to complete
3985 * the process of deleting those.
3986 * OR it is the EXT4_BOOT_LOADER_INO which is
3987 * not initialized on a new filesystem. */
3989 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
3990 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
3991 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
3992 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
3994 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
3995 inode
->i_size
= ext4_isize(raw_inode
);
3996 ei
->i_disksize
= inode
->i_size
;
3998 ei
->i_reserved_quota
= 0;
4000 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4001 ei
->i_block_group
= iloc
.block_group
;
4002 ei
->i_last_alloc_group
= ~0;
4004 * NOTE! The in-memory inode i_data array is in little-endian order
4005 * even on big-endian machines: we do NOT byteswap the block numbers!
4007 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4008 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4009 INIT_LIST_HEAD(&ei
->i_orphan
);
4012 * Set transaction id's of transactions that have to be committed
4013 * to finish f[data]sync. We set them to currently running transaction
4014 * as we cannot be sure that the inode or some of its metadata isn't
4015 * part of the transaction - the inode could have been reclaimed and
4016 * now it is reread from disk.
4019 transaction_t
*transaction
;
4022 read_lock(&journal
->j_state_lock
);
4023 if (journal
->j_running_transaction
)
4024 transaction
= journal
->j_running_transaction
;
4026 transaction
= journal
->j_committing_transaction
;
4028 tid
= transaction
->t_tid
;
4030 tid
= journal
->j_commit_sequence
;
4031 read_unlock(&journal
->j_state_lock
);
4032 ei
->i_sync_tid
= tid
;
4033 ei
->i_datasync_tid
= tid
;
4036 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4037 if (ei
->i_extra_isize
== 0) {
4038 /* The extra space is currently unused. Use it. */
4039 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4040 EXT4_GOOD_OLD_INODE_SIZE
;
4042 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4046 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4047 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4048 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4049 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4051 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4052 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4053 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4054 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4056 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4061 if (ei
->i_file_acl
&&
4062 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4063 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4067 } else if (!ext4_has_inline_data(inode
)) {
4068 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4069 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4070 (S_ISLNK(inode
->i_mode
) &&
4071 !ext4_inode_is_fast_symlink(inode
))))
4072 /* Validate extent which is part of inode */
4073 ret
= ext4_ext_check_inode(inode
);
4074 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4075 (S_ISLNK(inode
->i_mode
) &&
4076 !ext4_inode_is_fast_symlink(inode
))) {
4077 /* Validate block references which are part of inode */
4078 ret
= ext4_ind_check_inode(inode
);
4084 if (S_ISREG(inode
->i_mode
)) {
4085 inode
->i_op
= &ext4_file_inode_operations
;
4086 if (test_opt(inode
->i_sb
, DAX
))
4087 inode
->i_fop
= &ext4_dax_file_operations
;
4089 inode
->i_fop
= &ext4_file_operations
;
4090 ext4_set_aops(inode
);
4091 } else if (S_ISDIR(inode
->i_mode
)) {
4092 inode
->i_op
= &ext4_dir_inode_operations
;
4093 inode
->i_fop
= &ext4_dir_operations
;
4094 } else if (S_ISLNK(inode
->i_mode
)) {
4095 if (ext4_inode_is_fast_symlink(inode
)) {
4096 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4097 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4098 sizeof(ei
->i_data
) - 1);
4100 inode
->i_op
= &ext4_symlink_inode_operations
;
4101 ext4_set_aops(inode
);
4103 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4104 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4105 inode
->i_op
= &ext4_special_inode_operations
;
4106 if (raw_inode
->i_block
[0])
4107 init_special_inode(inode
, inode
->i_mode
,
4108 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4110 init_special_inode(inode
, inode
->i_mode
,
4111 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4112 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4113 make_bad_inode(inode
);
4116 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4120 ext4_set_inode_flags(inode
);
4121 unlock_new_inode(inode
);
4127 return ERR_PTR(ret
);
4130 struct inode
*ext4_iget_normal(struct super_block
*sb
, unsigned long ino
)
4132 if (ino
< EXT4_FIRST_INO(sb
) && ino
!= EXT4_ROOT_INO
)
4133 return ERR_PTR(-EIO
);
4134 return ext4_iget(sb
, ino
);
4137 static int ext4_inode_blocks_set(handle_t
*handle
,
4138 struct ext4_inode
*raw_inode
,
4139 struct ext4_inode_info
*ei
)
4141 struct inode
*inode
= &(ei
->vfs_inode
);
4142 u64 i_blocks
= inode
->i_blocks
;
4143 struct super_block
*sb
= inode
->i_sb
;
4145 if (i_blocks
<= ~0U) {
4147 * i_blocks can be represented in a 32 bit variable
4148 * as multiple of 512 bytes
4150 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4151 raw_inode
->i_blocks_high
= 0;
4152 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4155 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4158 if (i_blocks
<= 0xffffffffffffULL
) {
4160 * i_blocks can be represented in a 48 bit variable
4161 * as multiple of 512 bytes
4163 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4164 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4165 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4167 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4168 /* i_block is stored in file system block size */
4169 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4170 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4171 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4176 struct other_inode
{
4177 unsigned long orig_ino
;
4178 struct ext4_inode
*raw_inode
;
4181 static int other_inode_match(struct inode
* inode
, unsigned long ino
,
4184 struct other_inode
*oi
= (struct other_inode
*) data
;
4186 if ((inode
->i_ino
!= ino
) ||
4187 (inode
->i_state
& (I_FREEING
| I_WILL_FREE
| I_NEW
|
4188 I_DIRTY_SYNC
| I_DIRTY_DATASYNC
)) ||
4189 ((inode
->i_state
& I_DIRTY_TIME
) == 0))
4191 spin_lock(&inode
->i_lock
);
4192 if (((inode
->i_state
& (I_FREEING
| I_WILL_FREE
| I_NEW
|
4193 I_DIRTY_SYNC
| I_DIRTY_DATASYNC
)) == 0) &&
4194 (inode
->i_state
& I_DIRTY_TIME
)) {
4195 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4197 inode
->i_state
&= ~(I_DIRTY_TIME
| I_DIRTY_TIME_EXPIRED
);
4198 spin_unlock(&inode
->i_lock
);
4200 spin_lock(&ei
->i_raw_lock
);
4201 EXT4_INODE_SET_XTIME(i_ctime
, inode
, oi
->raw_inode
);
4202 EXT4_INODE_SET_XTIME(i_mtime
, inode
, oi
->raw_inode
);
4203 EXT4_INODE_SET_XTIME(i_atime
, inode
, oi
->raw_inode
);
4204 ext4_inode_csum_set(inode
, oi
->raw_inode
, ei
);
4205 spin_unlock(&ei
->i_raw_lock
);
4206 trace_ext4_other_inode_update_time(inode
, oi
->orig_ino
);
4209 spin_unlock(&inode
->i_lock
);
4214 * Opportunistically update the other time fields for other inodes in
4215 * the same inode table block.
4217 static void ext4_update_other_inodes_time(struct super_block
*sb
,
4218 unsigned long orig_ino
, char *buf
)
4220 struct other_inode oi
;
4222 int i
, inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
4223 int inode_size
= EXT4_INODE_SIZE(sb
);
4225 oi
.orig_ino
= orig_ino
;
4226 ino
= orig_ino
& ~(inodes_per_block
- 1);
4227 for (i
= 0; i
< inodes_per_block
; i
++, ino
++, buf
+= inode_size
) {
4228 if (ino
== orig_ino
)
4230 oi
.raw_inode
= (struct ext4_inode
*) buf
;
4231 (void) find_inode_nowait(sb
, ino
, other_inode_match
, &oi
);
4236 * Post the struct inode info into an on-disk inode location in the
4237 * buffer-cache. This gobbles the caller's reference to the
4238 * buffer_head in the inode location struct.
4240 * The caller must have write access to iloc->bh.
4242 static int ext4_do_update_inode(handle_t
*handle
,
4243 struct inode
*inode
,
4244 struct ext4_iloc
*iloc
)
4246 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4247 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4248 struct buffer_head
*bh
= iloc
->bh
;
4249 struct super_block
*sb
= inode
->i_sb
;
4250 int err
= 0, rc
, block
;
4251 int need_datasync
= 0, set_large_file
= 0;
4255 spin_lock(&ei
->i_raw_lock
);
4257 /* For fields not tracked in the in-memory inode,
4258 * initialise them to zero for new inodes. */
4259 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4260 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4262 ext4_get_inode_flags(ei
);
4263 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4264 i_uid
= i_uid_read(inode
);
4265 i_gid
= i_gid_read(inode
);
4266 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4267 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4268 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4270 * Fix up interoperability with old kernels. Otherwise, old inodes get
4271 * re-used with the upper 16 bits of the uid/gid intact
4274 raw_inode
->i_uid_high
=
4275 cpu_to_le16(high_16_bits(i_uid
));
4276 raw_inode
->i_gid_high
=
4277 cpu_to_le16(high_16_bits(i_gid
));
4279 raw_inode
->i_uid_high
= 0;
4280 raw_inode
->i_gid_high
= 0;
4283 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4284 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4285 raw_inode
->i_uid_high
= 0;
4286 raw_inode
->i_gid_high
= 0;
4288 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4290 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4291 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4292 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4293 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4295 err
= ext4_inode_blocks_set(handle
, raw_inode
, ei
);
4297 spin_unlock(&ei
->i_raw_lock
);
4300 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4301 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4302 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
)))
4303 raw_inode
->i_file_acl_high
=
4304 cpu_to_le16(ei
->i_file_acl
>> 32);
4305 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4306 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4307 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4310 if (ei
->i_disksize
> 0x7fffffffULL
) {
4311 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4312 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4313 EXT4_SB(sb
)->s_es
->s_rev_level
==
4314 cpu_to_le32(EXT4_GOOD_OLD_REV
))
4317 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4318 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4319 if (old_valid_dev(inode
->i_rdev
)) {
4320 raw_inode
->i_block
[0] =
4321 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4322 raw_inode
->i_block
[1] = 0;
4324 raw_inode
->i_block
[0] = 0;
4325 raw_inode
->i_block
[1] =
4326 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4327 raw_inode
->i_block
[2] = 0;
4329 } else if (!ext4_has_inline_data(inode
)) {
4330 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4331 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4334 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4335 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4336 if (ei
->i_extra_isize
) {
4337 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4338 raw_inode
->i_version_hi
=
4339 cpu_to_le32(inode
->i_version
>> 32);
4340 raw_inode
->i_extra_isize
=
4341 cpu_to_le16(ei
->i_extra_isize
);
4344 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4345 spin_unlock(&ei
->i_raw_lock
);
4346 if (inode
->i_sb
->s_flags
& MS_LAZYTIME
)
4347 ext4_update_other_inodes_time(inode
->i_sb
, inode
->i_ino
,
4350 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4351 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4354 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4355 if (set_large_file
) {
4356 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get write access");
4357 err
= ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
);
4360 ext4_update_dynamic_rev(sb
);
4361 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4362 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4363 ext4_handle_sync(handle
);
4364 err
= ext4_handle_dirty_super(handle
, sb
);
4366 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4369 ext4_std_error(inode
->i_sb
, err
);
4374 * ext4_write_inode()
4376 * We are called from a few places:
4378 * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files.
4379 * Here, there will be no transaction running. We wait for any running
4380 * transaction to commit.
4382 * - Within flush work (sys_sync(), kupdate and such).
4383 * We wait on commit, if told to.
4385 * - Within iput_final() -> write_inode_now()
4386 * We wait on commit, if told to.
4388 * In all cases it is actually safe for us to return without doing anything,
4389 * because the inode has been copied into a raw inode buffer in
4390 * ext4_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL
4393 * Note that we are absolutely dependent upon all inode dirtiers doing the
4394 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4395 * which we are interested.
4397 * It would be a bug for them to not do this. The code:
4399 * mark_inode_dirty(inode)
4401 * inode->i_size = expr;
4403 * is in error because write_inode() could occur while `stuff()' is running,
4404 * and the new i_size will be lost. Plus the inode will no longer be on the
4405 * superblock's dirty inode list.
4407 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4411 if (WARN_ON_ONCE(current
->flags
& PF_MEMALLOC
))
4414 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4415 if (ext4_journal_current_handle()) {
4416 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4422 * No need to force transaction in WB_SYNC_NONE mode. Also
4423 * ext4_sync_fs() will force the commit after everything is
4426 if (wbc
->sync_mode
!= WB_SYNC_ALL
|| wbc
->for_sync
)
4429 err
= ext4_force_commit(inode
->i_sb
);
4431 struct ext4_iloc iloc
;
4433 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4437 * sync(2) will flush the whole buffer cache. No need to do
4438 * it here separately for each inode.
4440 if (wbc
->sync_mode
== WB_SYNC_ALL
&& !wbc
->for_sync
)
4441 sync_dirty_buffer(iloc
.bh
);
4442 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4443 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4444 "IO error syncing inode");
4453 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4454 * buffers that are attached to a page stradding i_size and are undergoing
4455 * commit. In that case we have to wait for commit to finish and try again.
4457 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4461 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4462 tid_t commit_tid
= 0;
4465 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4467 * All buffers in the last page remain valid? Then there's nothing to
4468 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4471 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4474 page
= find_lock_page(inode
->i_mapping
,
4475 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4478 ret
= __ext4_journalled_invalidatepage(page
, offset
,
4479 PAGE_CACHE_SIZE
- offset
);
4481 page_cache_release(page
);
4485 read_lock(&journal
->j_state_lock
);
4486 if (journal
->j_committing_transaction
)
4487 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4488 read_unlock(&journal
->j_state_lock
);
4490 jbd2_log_wait_commit(journal
, commit_tid
);
4497 * Called from notify_change.
4499 * We want to trap VFS attempts to truncate the file as soon as
4500 * possible. In particular, we want to make sure that when the VFS
4501 * shrinks i_size, we put the inode on the orphan list and modify
4502 * i_disksize immediately, so that during the subsequent flushing of
4503 * dirty pages and freeing of disk blocks, we can guarantee that any
4504 * commit will leave the blocks being flushed in an unused state on
4505 * disk. (On recovery, the inode will get truncated and the blocks will
4506 * be freed, so we have a strong guarantee that no future commit will
4507 * leave these blocks visible to the user.)
4509 * Another thing we have to assure is that if we are in ordered mode
4510 * and inode is still attached to the committing transaction, we must
4511 * we start writeout of all the dirty pages which are being truncated.
4512 * This way we are sure that all the data written in the previous
4513 * transaction are already on disk (truncate waits for pages under
4516 * Called with inode->i_mutex down.
4518 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4520 struct inode
*inode
= dentry
->d_inode
;
4523 const unsigned int ia_valid
= attr
->ia_valid
;
4525 error
= inode_change_ok(inode
, attr
);
4529 if (is_quota_modification(inode
, attr
))
4530 dquot_initialize(inode
);
4531 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4532 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4535 /* (user+group)*(old+new) structure, inode write (sb,
4536 * inode block, ? - but truncate inode update has it) */
4537 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4538 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4539 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4540 if (IS_ERR(handle
)) {
4541 error
= PTR_ERR(handle
);
4544 error
= dquot_transfer(inode
, attr
);
4546 ext4_journal_stop(handle
);
4549 /* Update corresponding info in inode so that everything is in
4550 * one transaction */
4551 if (attr
->ia_valid
& ATTR_UID
)
4552 inode
->i_uid
= attr
->ia_uid
;
4553 if (attr
->ia_valid
& ATTR_GID
)
4554 inode
->i_gid
= attr
->ia_gid
;
4555 error
= ext4_mark_inode_dirty(handle
, inode
);
4556 ext4_journal_stop(handle
);
4559 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4562 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4563 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4565 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4569 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4570 inode_inc_iversion(inode
);
4572 if (S_ISREG(inode
->i_mode
) &&
4573 (attr
->ia_size
< inode
->i_size
)) {
4574 if (ext4_should_order_data(inode
)) {
4575 error
= ext4_begin_ordered_truncate(inode
,
4580 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4581 if (IS_ERR(handle
)) {
4582 error
= PTR_ERR(handle
);
4585 if (ext4_handle_valid(handle
)) {
4586 error
= ext4_orphan_add(handle
, inode
);
4589 down_write(&EXT4_I(inode
)->i_data_sem
);
4590 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4591 rc
= ext4_mark_inode_dirty(handle
, inode
);
4595 * We have to update i_size under i_data_sem together
4596 * with i_disksize to avoid races with writeback code
4597 * running ext4_wb_update_i_disksize().
4600 i_size_write(inode
, attr
->ia_size
);
4601 up_write(&EXT4_I(inode
)->i_data_sem
);
4602 ext4_journal_stop(handle
);
4604 ext4_orphan_del(NULL
, inode
);
4608 loff_t oldsize
= inode
->i_size
;
4610 i_size_write(inode
, attr
->ia_size
);
4611 pagecache_isize_extended(inode
, oldsize
, inode
->i_size
);
4615 * Blocks are going to be removed from the inode. Wait
4616 * for dio in flight. Temporarily disable
4617 * dioread_nolock to prevent livelock.
4620 if (!ext4_should_journal_data(inode
)) {
4621 ext4_inode_block_unlocked_dio(inode
);
4622 inode_dio_wait(inode
);
4623 ext4_inode_resume_unlocked_dio(inode
);
4625 ext4_wait_for_tail_page_commit(inode
);
4628 * Truncate pagecache after we've waited for commit
4629 * in data=journal mode to make pages freeable.
4631 truncate_pagecache(inode
, inode
->i_size
);
4634 * We want to call ext4_truncate() even if attr->ia_size ==
4635 * inode->i_size for cases like truncation of fallocated space
4637 if (attr
->ia_valid
& ATTR_SIZE
)
4638 ext4_truncate(inode
);
4641 setattr_copy(inode
, attr
);
4642 mark_inode_dirty(inode
);
4646 * If the call to ext4_truncate failed to get a transaction handle at
4647 * all, we need to clean up the in-core orphan list manually.
4649 if (orphan
&& inode
->i_nlink
)
4650 ext4_orphan_del(NULL
, inode
);
4652 if (!rc
&& (ia_valid
& ATTR_MODE
))
4653 rc
= posix_acl_chmod(inode
, inode
->i_mode
);
4656 ext4_std_error(inode
->i_sb
, error
);
4662 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4665 struct inode
*inode
;
4666 unsigned long long delalloc_blocks
;
4668 inode
= dentry
->d_inode
;
4669 generic_fillattr(inode
, stat
);
4672 * If there is inline data in the inode, the inode will normally not
4673 * have data blocks allocated (it may have an external xattr block).
4674 * Report at least one sector for such files, so tools like tar, rsync,
4675 * others doen't incorrectly think the file is completely sparse.
4677 if (unlikely(ext4_has_inline_data(inode
)))
4678 stat
->blocks
+= (stat
->size
+ 511) >> 9;
4681 * We can't update i_blocks if the block allocation is delayed
4682 * otherwise in the case of system crash before the real block
4683 * allocation is done, we will have i_blocks inconsistent with
4684 * on-disk file blocks.
4685 * We always keep i_blocks updated together with real
4686 * allocation. But to not confuse with user, stat
4687 * will return the blocks that include the delayed allocation
4688 * blocks for this file.
4690 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4691 EXT4_I(inode
)->i_reserved_data_blocks
);
4692 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
- 9);
4696 static int ext4_index_trans_blocks(struct inode
*inode
, int lblocks
,
4699 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4700 return ext4_ind_trans_blocks(inode
, lblocks
);
4701 return ext4_ext_index_trans_blocks(inode
, pextents
);
4705 * Account for index blocks, block groups bitmaps and block group
4706 * descriptor blocks if modify datablocks and index blocks
4707 * worse case, the indexs blocks spread over different block groups
4709 * If datablocks are discontiguous, they are possible to spread over
4710 * different block groups too. If they are contiguous, with flexbg,
4711 * they could still across block group boundary.
4713 * Also account for superblock, inode, quota and xattr blocks
4715 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
4718 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4724 * How many index blocks need to touch to map @lblocks logical blocks
4725 * to @pextents physical extents?
4727 idxblocks
= ext4_index_trans_blocks(inode
, lblocks
, pextents
);
4732 * Now let's see how many group bitmaps and group descriptors need
4735 groups
= idxblocks
+ pextents
;
4737 if (groups
> ngroups
)
4739 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4740 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4742 /* bitmaps and block group descriptor blocks */
4743 ret
+= groups
+ gdpblocks
;
4745 /* Blocks for super block, inode, quota and xattr blocks */
4746 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4752 * Calculate the total number of credits to reserve to fit
4753 * the modification of a single pages into a single transaction,
4754 * which may include multiple chunks of block allocations.
4756 * This could be called via ext4_write_begin()
4758 * We need to consider the worse case, when
4759 * one new block per extent.
4761 int ext4_writepage_trans_blocks(struct inode
*inode
)
4763 int bpp
= ext4_journal_blocks_per_page(inode
);
4766 ret
= ext4_meta_trans_blocks(inode
, bpp
, bpp
);
4768 /* Account for data blocks for journalled mode */
4769 if (ext4_should_journal_data(inode
))
4775 * Calculate the journal credits for a chunk of data modification.
4777 * This is called from DIO, fallocate or whoever calling
4778 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4780 * journal buffers for data blocks are not included here, as DIO
4781 * and fallocate do no need to journal data buffers.
4783 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4785 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4789 * The caller must have previously called ext4_reserve_inode_write().
4790 * Give this, we know that the caller already has write access to iloc->bh.
4792 int ext4_mark_iloc_dirty(handle_t
*handle
,
4793 struct inode
*inode
, struct ext4_iloc
*iloc
)
4797 if (IS_I_VERSION(inode
))
4798 inode_inc_iversion(inode
);
4800 /* the do_update_inode consumes one bh->b_count */
4803 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4804 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4810 * On success, We end up with an outstanding reference count against
4811 * iloc->bh. This _must_ be cleaned up later.
4815 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4816 struct ext4_iloc
*iloc
)
4820 err
= ext4_get_inode_loc(inode
, iloc
);
4822 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4823 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4829 ext4_std_error(inode
->i_sb
, err
);
4834 * Expand an inode by new_extra_isize bytes.
4835 * Returns 0 on success or negative error number on failure.
4837 static int ext4_expand_extra_isize(struct inode
*inode
,
4838 unsigned int new_extra_isize
,
4839 struct ext4_iloc iloc
,
4842 struct ext4_inode
*raw_inode
;
4843 struct ext4_xattr_ibody_header
*header
;
4845 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
4848 raw_inode
= ext4_raw_inode(&iloc
);
4850 header
= IHDR(inode
, raw_inode
);
4852 /* No extended attributes present */
4853 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
4854 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4855 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
4857 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
4861 /* try to expand with EAs present */
4862 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
4867 * What we do here is to mark the in-core inode as clean with respect to inode
4868 * dirtiness (it may still be data-dirty).
4869 * This means that the in-core inode may be reaped by prune_icache
4870 * without having to perform any I/O. This is a very good thing,
4871 * because *any* task may call prune_icache - even ones which
4872 * have a transaction open against a different journal.
4874 * Is this cheating? Not really. Sure, we haven't written the
4875 * inode out, but prune_icache isn't a user-visible syncing function.
4876 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
4877 * we start and wait on commits.
4879 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
4881 struct ext4_iloc iloc
;
4882 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4883 static unsigned int mnt_count
;
4887 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
4888 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
4889 if (ext4_handle_valid(handle
) &&
4890 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
4891 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
4893 * We need extra buffer credits since we may write into EA block
4894 * with this same handle. If journal_extend fails, then it will
4895 * only result in a minor loss of functionality for that inode.
4896 * If this is felt to be critical, then e2fsck should be run to
4897 * force a large enough s_min_extra_isize.
4899 if ((jbd2_journal_extend(handle
,
4900 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
4901 ret
= ext4_expand_extra_isize(inode
,
4902 sbi
->s_want_extra_isize
,
4905 ext4_set_inode_state(inode
,
4906 EXT4_STATE_NO_EXPAND
);
4908 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
4909 ext4_warning(inode
->i_sb
,
4910 "Unable to expand inode %lu. Delete"
4911 " some EAs or run e2fsck.",
4914 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
4920 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
4925 * ext4_dirty_inode() is called from __mark_inode_dirty()
4927 * We're really interested in the case where a file is being extended.
4928 * i_size has been changed by generic_commit_write() and we thus need
4929 * to include the updated inode in the current transaction.
4931 * Also, dquot_alloc_block() will always dirty the inode when blocks
4932 * are allocated to the file.
4934 * If the inode is marked synchronous, we don't honour that here - doing
4935 * so would cause a commit on atime updates, which we don't bother doing.
4936 * We handle synchronous inodes at the highest possible level.
4938 * If only the I_DIRTY_TIME flag is set, we can skip everything. If
4939 * I_DIRTY_TIME and I_DIRTY_SYNC is set, the only inode fields we need
4940 * to copy into the on-disk inode structure are the timestamp files.
4942 void ext4_dirty_inode(struct inode
*inode
, int flags
)
4946 if (flags
== I_DIRTY_TIME
)
4948 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
4952 ext4_mark_inode_dirty(handle
, inode
);
4954 ext4_journal_stop(handle
);
4961 * Bind an inode's backing buffer_head into this transaction, to prevent
4962 * it from being flushed to disk early. Unlike
4963 * ext4_reserve_inode_write, this leaves behind no bh reference and
4964 * returns no iloc structure, so the caller needs to repeat the iloc
4965 * lookup to mark the inode dirty later.
4967 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
4969 struct ext4_iloc iloc
;
4973 err
= ext4_get_inode_loc(inode
, &iloc
);
4975 BUFFER_TRACE(iloc
.bh
, "get_write_access");
4976 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
4978 err
= ext4_handle_dirty_metadata(handle
,
4984 ext4_std_error(inode
->i_sb
, err
);
4989 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
4996 * We have to be very careful here: changing a data block's
4997 * journaling status dynamically is dangerous. If we write a
4998 * data block to the journal, change the status and then delete
4999 * that block, we risk forgetting to revoke the old log record
5000 * from the journal and so a subsequent replay can corrupt data.
5001 * So, first we make sure that the journal is empty and that
5002 * nobody is changing anything.
5005 journal
= EXT4_JOURNAL(inode
);
5008 if (is_journal_aborted(journal
))
5010 /* We have to allocate physical blocks for delalloc blocks
5011 * before flushing journal. otherwise delalloc blocks can not
5012 * be allocated any more. even more truncate on delalloc blocks
5013 * could trigger BUG by flushing delalloc blocks in journal.
5014 * There is no delalloc block in non-journal data mode.
5016 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5017 err
= ext4_alloc_da_blocks(inode
);
5022 /* Wait for all existing dio workers */
5023 ext4_inode_block_unlocked_dio(inode
);
5024 inode_dio_wait(inode
);
5026 jbd2_journal_lock_updates(journal
);
5029 * OK, there are no updates running now, and all cached data is
5030 * synced to disk. We are now in a completely consistent state
5031 * which doesn't have anything in the journal, and we know that
5032 * no filesystem updates are running, so it is safe to modify
5033 * the inode's in-core data-journaling state flag now.
5037 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5039 err
= jbd2_journal_flush(journal
);
5041 jbd2_journal_unlock_updates(journal
);
5042 ext4_inode_resume_unlocked_dio(inode
);
5045 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5047 ext4_set_aops(inode
);
5049 jbd2_journal_unlock_updates(journal
);
5050 ext4_inode_resume_unlocked_dio(inode
);
5052 /* Finally we can mark the inode as dirty. */
5054 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5056 return PTR_ERR(handle
);
5058 err
= ext4_mark_inode_dirty(handle
, inode
);
5059 ext4_handle_sync(handle
);
5060 ext4_journal_stop(handle
);
5061 ext4_std_error(inode
->i_sb
, err
);
5066 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5068 return !buffer_mapped(bh
);
5071 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5073 struct page
*page
= vmf
->page
;
5077 struct file
*file
= vma
->vm_file
;
5078 struct inode
*inode
= file_inode(file
);
5079 struct address_space
*mapping
= inode
->i_mapping
;
5081 get_block_t
*get_block
;
5084 sb_start_pagefault(inode
->i_sb
);
5085 file_update_time(vma
->vm_file
);
5086 /* Delalloc case is easy... */
5087 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5088 !ext4_should_journal_data(inode
) &&
5089 !ext4_nonda_switch(inode
->i_sb
)) {
5091 ret
= __block_page_mkwrite(vma
, vmf
,
5092 ext4_da_get_block_prep
);
5093 } while (ret
== -ENOSPC
&&
5094 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5099 size
= i_size_read(inode
);
5100 /* Page got truncated from under us? */
5101 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5103 ret
= VM_FAULT_NOPAGE
;
5107 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5108 len
= size
& ~PAGE_CACHE_MASK
;
5110 len
= PAGE_CACHE_SIZE
;
5112 * Return if we have all the buffers mapped. This avoids the need to do
5113 * journal_start/journal_stop which can block and take a long time
5115 if (page_has_buffers(page
)) {
5116 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5118 ext4_bh_unmapped
)) {
5119 /* Wait so that we don't change page under IO */
5120 wait_for_stable_page(page
);
5121 ret
= VM_FAULT_LOCKED
;
5126 /* OK, we need to fill the hole... */
5127 if (ext4_should_dioread_nolock(inode
))
5128 get_block
= ext4_get_block_write
;
5130 get_block
= ext4_get_block
;
5132 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5133 ext4_writepage_trans_blocks(inode
));
5134 if (IS_ERR(handle
)) {
5135 ret
= VM_FAULT_SIGBUS
;
5138 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5139 if (!ret
&& ext4_should_journal_data(inode
)) {
5140 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5141 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5143 ret
= VM_FAULT_SIGBUS
;
5144 ext4_journal_stop(handle
);
5147 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5149 ext4_journal_stop(handle
);
5150 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5153 ret
= block_page_mkwrite_return(ret
);
5155 sb_end_pagefault(inode
->i_sb
);