2 * linux/fs/ext4/inode.c
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
11 * linux/fs/minix/inode.c
13 * Copyright (C) 1991, 1992 Linus Torvalds
15 * 64-bit file support on 64-bit platforms by Jakub Jelinek
16 * (jj@sunsite.ms.mff.cuni.cz)
18 * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
22 #include <linux/time.h>
23 #include <linux/jbd2.h>
24 #include <linux/highuid.h>
25 #include <linux/pagemap.h>
26 #include <linux/quotaops.h>
27 #include <linux/string.h>
28 #include <linux/buffer_head.h>
29 #include <linux/writeback.h>
30 #include <linux/pagevec.h>
31 #include <linux/mpage.h>
32 #include <linux/namei.h>
33 #include <linux/uio.h>
34 #include <linux/bio.h>
35 #include <linux/workqueue.h>
36 #include <linux/kernel.h>
37 #include <linux/printk.h>
38 #include <linux/slab.h>
39 #include <linux/ratelimit.h>
40 #include <linux/aio.h>
41 #include <linux/bitops.h>
43 #include "ext4_jbd2.h"
48 #include <trace/events/ext4.h>
50 #define MPAGE_DA_EXTENT_TAIL 0x01
52 static __u32
ext4_inode_csum(struct inode
*inode
, struct ext4_inode
*raw
,
53 struct ext4_inode_info
*ei
)
55 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
60 csum_lo
= le16_to_cpu(raw
->i_checksum_lo
);
61 raw
->i_checksum_lo
= 0;
62 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
63 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
)) {
64 csum_hi
= le16_to_cpu(raw
->i_checksum_hi
);
65 raw
->i_checksum_hi
= 0;
68 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)raw
,
69 EXT4_INODE_SIZE(inode
->i_sb
));
71 raw
->i_checksum_lo
= cpu_to_le16(csum_lo
);
72 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
73 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
74 raw
->i_checksum_hi
= cpu_to_le16(csum_hi
);
79 static int ext4_inode_csum_verify(struct inode
*inode
, struct ext4_inode
*raw
,
80 struct ext4_inode_info
*ei
)
82 __u32 provided
, calculated
;
84 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
85 cpu_to_le32(EXT4_OS_LINUX
) ||
86 !ext4_has_metadata_csum(inode
->i_sb
))
89 provided
= le16_to_cpu(raw
->i_checksum_lo
);
90 calculated
= ext4_inode_csum(inode
, raw
, ei
);
91 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
92 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
93 provided
|= ((__u32
)le16_to_cpu(raw
->i_checksum_hi
)) << 16;
97 return provided
== calculated
;
100 static void ext4_inode_csum_set(struct inode
*inode
, struct ext4_inode
*raw
,
101 struct ext4_inode_info
*ei
)
105 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
106 cpu_to_le32(EXT4_OS_LINUX
) ||
107 !ext4_has_metadata_csum(inode
->i_sb
))
110 csum
= ext4_inode_csum(inode
, raw
, ei
);
111 raw
->i_checksum_lo
= cpu_to_le16(csum
& 0xFFFF);
112 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
113 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
114 raw
->i_checksum_hi
= cpu_to_le16(csum
>> 16);
117 static inline int ext4_begin_ordered_truncate(struct inode
*inode
,
120 trace_ext4_begin_ordered_truncate(inode
, new_size
);
122 * If jinode is zero, then we never opened the file for
123 * writing, so there's no need to call
124 * jbd2_journal_begin_ordered_truncate() since there's no
125 * outstanding writes we need to flush.
127 if (!EXT4_I(inode
)->jinode
)
129 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode
),
130 EXT4_I(inode
)->jinode
,
134 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
135 unsigned int length
);
136 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
137 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
138 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
142 * Test whether an inode is a fast symlink.
144 static int ext4_inode_is_fast_symlink(struct inode
*inode
)
146 int ea_blocks
= EXT4_I(inode
)->i_file_acl
?
147 EXT4_CLUSTER_SIZE(inode
->i_sb
) >> 9 : 0;
149 if (ext4_has_inline_data(inode
))
152 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
156 * Restart the transaction associated with *handle. This does a commit,
157 * so before we call here everything must be consistently dirtied against
160 int ext4_truncate_restart_trans(handle_t
*handle
, struct inode
*inode
,
166 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
167 * moment, get_block can be called only for blocks inside i_size since
168 * page cache has been already dropped and writes are blocked by
169 * i_mutex. So we can safely drop the i_data_sem here.
171 BUG_ON(EXT4_JOURNAL(inode
) == NULL
);
172 jbd_debug(2, "restarting handle %p\n", handle
);
173 up_write(&EXT4_I(inode
)->i_data_sem
);
174 ret
= ext4_journal_restart(handle
, nblocks
);
175 down_write(&EXT4_I(inode
)->i_data_sem
);
176 ext4_discard_preallocations(inode
);
182 * Called at the last iput() if i_nlink is zero.
184 void ext4_evict_inode(struct inode
*inode
)
189 trace_ext4_evict_inode(inode
);
191 if (inode
->i_nlink
) {
193 * When journalling data dirty buffers are tracked only in the
194 * journal. So although mm thinks everything is clean and
195 * ready for reaping the inode might still have some pages to
196 * write in the running transaction or waiting to be
197 * checkpointed. Thus calling jbd2_journal_invalidatepage()
198 * (via truncate_inode_pages()) to discard these buffers can
199 * cause data loss. Also even if we did not discard these
200 * buffers, we would have no way to find them after the inode
201 * is reaped and thus user could see stale data if he tries to
202 * read them before the transaction is checkpointed. So be
203 * careful and force everything to disk here... We use
204 * ei->i_datasync_tid to store the newest transaction
205 * containing inode's data.
207 * Note that directories do not have this problem because they
208 * don't use page cache.
210 if (ext4_should_journal_data(inode
) &&
211 (S_ISLNK(inode
->i_mode
) || S_ISREG(inode
->i_mode
)) &&
212 inode
->i_ino
!= EXT4_JOURNAL_INO
) {
213 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
214 tid_t commit_tid
= EXT4_I(inode
)->i_datasync_tid
;
216 jbd2_complete_transaction(journal
, commit_tid
);
217 filemap_write_and_wait(&inode
->i_data
);
219 truncate_inode_pages_final(&inode
->i_data
);
221 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
225 if (is_bad_inode(inode
))
227 dquot_initialize(inode
);
229 if (ext4_should_order_data(inode
))
230 ext4_begin_ordered_truncate(inode
, 0);
231 truncate_inode_pages_final(&inode
->i_data
);
233 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
236 * Protect us against freezing - iput() caller didn't have to have any
237 * protection against it
239 sb_start_intwrite(inode
->i_sb
);
240 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
,
241 ext4_blocks_for_truncate(inode
)+3);
242 if (IS_ERR(handle
)) {
243 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
245 * If we're going to skip the normal cleanup, we still need to
246 * make sure that the in-core orphan linked list is properly
249 ext4_orphan_del(NULL
, inode
);
250 sb_end_intwrite(inode
->i_sb
);
255 ext4_handle_sync(handle
);
257 err
= ext4_mark_inode_dirty(handle
, inode
);
259 ext4_warning(inode
->i_sb
,
260 "couldn't mark inode dirty (err %d)", err
);
264 ext4_truncate(inode
);
267 * ext4_ext_truncate() doesn't reserve any slop when it
268 * restarts journal transactions; therefore there may not be
269 * enough credits left in the handle to remove the inode from
270 * the orphan list and set the dtime field.
272 if (!ext4_handle_has_enough_credits(handle
, 3)) {
273 err
= ext4_journal_extend(handle
, 3);
275 err
= ext4_journal_restart(handle
, 3);
277 ext4_warning(inode
->i_sb
,
278 "couldn't extend journal (err %d)", err
);
280 ext4_journal_stop(handle
);
281 ext4_orphan_del(NULL
, inode
);
282 sb_end_intwrite(inode
->i_sb
);
288 * Kill off the orphan record which ext4_truncate created.
289 * AKPM: I think this can be inside the above `if'.
290 * Note that ext4_orphan_del() has to be able to cope with the
291 * deletion of a non-existent orphan - this is because we don't
292 * know if ext4_truncate() actually created an orphan record.
293 * (Well, we could do this if we need to, but heck - it works)
295 ext4_orphan_del(handle
, inode
);
296 EXT4_I(inode
)->i_dtime
= get_seconds();
299 * One subtle ordering requirement: if anything has gone wrong
300 * (transaction abort, IO errors, whatever), then we can still
301 * do these next steps (the fs will already have been marked as
302 * having errors), but we can't free the inode if the mark_dirty
305 if (ext4_mark_inode_dirty(handle
, inode
))
306 /* If that failed, just do the required in-core inode clear. */
307 ext4_clear_inode(inode
);
309 ext4_free_inode(handle
, inode
);
310 ext4_journal_stop(handle
);
311 sb_end_intwrite(inode
->i_sb
);
314 ext4_clear_inode(inode
); /* We must guarantee clearing of inode... */
318 qsize_t
*ext4_get_reserved_space(struct inode
*inode
)
320 return &EXT4_I(inode
)->i_reserved_quota
;
325 * Called with i_data_sem down, which is important since we can call
326 * ext4_discard_preallocations() from here.
328 void ext4_da_update_reserve_space(struct inode
*inode
,
329 int used
, int quota_claim
)
331 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
332 struct ext4_inode_info
*ei
= EXT4_I(inode
);
334 spin_lock(&ei
->i_block_reservation_lock
);
335 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
336 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
337 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
338 "with only %d reserved data blocks",
339 __func__
, inode
->i_ino
, used
,
340 ei
->i_reserved_data_blocks
);
342 used
= ei
->i_reserved_data_blocks
;
345 /* Update per-inode reservations */
346 ei
->i_reserved_data_blocks
-= used
;
347 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, used
);
349 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
351 /* Update quota subsystem for data blocks */
353 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
356 * We did fallocate with an offset that is already delayed
357 * allocated. So on delayed allocated writeback we should
358 * not re-claim the quota for fallocated blocks.
360 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
364 * If we have done all the pending block allocations and if
365 * there aren't any writers on the inode, we can discard the
366 * inode's preallocations.
368 if ((ei
->i_reserved_data_blocks
== 0) &&
369 (atomic_read(&inode
->i_writecount
) == 0))
370 ext4_discard_preallocations(inode
);
373 static int __check_block_validity(struct inode
*inode
, const char *func
,
375 struct ext4_map_blocks
*map
)
377 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
379 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
380 "lblock %lu mapped to illegal pblock "
381 "(length %d)", (unsigned long) map
->m_lblk
,
388 #define check_block_validity(inode, map) \
389 __check_block_validity((inode), __func__, __LINE__, (map))
391 #ifdef ES_AGGRESSIVE_TEST
392 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
394 struct ext4_map_blocks
*es_map
,
395 struct ext4_map_blocks
*map
,
402 * There is a race window that the result is not the same.
403 * e.g. xfstests #223 when dioread_nolock enables. The reason
404 * is that we lookup a block mapping in extent status tree with
405 * out taking i_data_sem. So at the time the unwritten extent
406 * could be converted.
408 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
409 down_read(&EXT4_I(inode
)->i_data_sem
);
410 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
411 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
412 EXT4_GET_BLOCKS_KEEP_SIZE
);
414 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
415 EXT4_GET_BLOCKS_KEEP_SIZE
);
417 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
418 up_read((&EXT4_I(inode
)->i_data_sem
));
421 * We don't check m_len because extent will be collpased in status
422 * tree. So the m_len might not equal.
424 if (es_map
->m_lblk
!= map
->m_lblk
||
425 es_map
->m_flags
!= map
->m_flags
||
426 es_map
->m_pblk
!= map
->m_pblk
) {
427 printk("ES cache assertion failed for inode: %lu "
428 "es_cached ex [%d/%d/%llu/%x] != "
429 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
430 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
431 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
432 map
->m_len
, map
->m_pblk
, map
->m_flags
,
436 #endif /* ES_AGGRESSIVE_TEST */
439 * The ext4_map_blocks() function tries to look up the requested blocks,
440 * and returns if the blocks are already mapped.
442 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
443 * and store the allocated blocks in the result buffer head and mark it
446 * If file type is extents based, it will call ext4_ext_map_blocks(),
447 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
450 * On success, it returns the number of blocks being mapped or allocated.
451 * if create==0 and the blocks are pre-allocated and unwritten block,
452 * the result buffer head is unmapped. If the create ==1, it will make sure
453 * the buffer head is mapped.
455 * It returns 0 if plain look up failed (blocks have not been allocated), in
456 * that case, buffer head is unmapped
458 * It returns the error in case of allocation failure.
460 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
461 struct ext4_map_blocks
*map
, int flags
)
463 struct extent_status es
;
466 #ifdef ES_AGGRESSIVE_TEST
467 struct ext4_map_blocks orig_map
;
469 memcpy(&orig_map
, map
, sizeof(*map
));
473 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
474 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
475 (unsigned long) map
->m_lblk
);
478 * ext4_map_blocks returns an int, and m_len is an unsigned int
480 if (unlikely(map
->m_len
> INT_MAX
))
481 map
->m_len
= INT_MAX
;
483 /* We can handle the block number less than EXT_MAX_BLOCKS */
484 if (unlikely(map
->m_lblk
>= EXT_MAX_BLOCKS
))
487 /* Lookup extent status tree firstly */
488 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
489 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
490 map
->m_pblk
= ext4_es_pblock(&es
) +
491 map
->m_lblk
- es
.es_lblk
;
492 map
->m_flags
|= ext4_es_is_written(&es
) ?
493 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
494 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
495 if (retval
> map
->m_len
)
498 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
503 #ifdef ES_AGGRESSIVE_TEST
504 ext4_map_blocks_es_recheck(handle
, inode
, map
,
511 * Try to see if we can get the block without requesting a new
514 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
515 down_read(&EXT4_I(inode
)->i_data_sem
);
516 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
517 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
518 EXT4_GET_BLOCKS_KEEP_SIZE
);
520 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
521 EXT4_GET_BLOCKS_KEEP_SIZE
);
526 if (unlikely(retval
!= map
->m_len
)) {
527 ext4_warning(inode
->i_sb
,
528 "ES len assertion failed for inode "
529 "%lu: retval %d != map->m_len %d",
530 inode
->i_ino
, retval
, map
->m_len
);
534 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
535 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
536 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
537 ext4_find_delalloc_range(inode
, map
->m_lblk
,
538 map
->m_lblk
+ map
->m_len
- 1))
539 status
|= EXTENT_STATUS_DELAYED
;
540 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
541 map
->m_len
, map
->m_pblk
, status
);
545 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
546 up_read((&EXT4_I(inode
)->i_data_sem
));
549 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
550 ret
= check_block_validity(inode
, map
);
555 /* If it is only a block(s) look up */
556 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
560 * Returns if the blocks have already allocated
562 * Note that if blocks have been preallocated
563 * ext4_ext_get_block() returns the create = 0
564 * with buffer head unmapped.
566 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
568 * If we need to convert extent to unwritten
569 * we continue and do the actual work in
570 * ext4_ext_map_blocks()
572 if (!(flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
))
576 * Here we clear m_flags because after allocating an new extent,
577 * it will be set again.
579 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
582 * New blocks allocate and/or writing to unwritten extent
583 * will possibly result in updating i_data, so we take
584 * the write lock of i_data_sem, and call get_block()
585 * with create == 1 flag.
587 down_write(&EXT4_I(inode
)->i_data_sem
);
590 * We need to check for EXT4 here because migrate
591 * could have changed the inode type in between
593 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
594 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
596 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
598 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
600 * We allocated new blocks which will result in
601 * i_data's format changing. Force the migrate
602 * to fail by clearing migrate flags
604 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
608 * Update reserved blocks/metadata blocks after successful
609 * block allocation which had been deferred till now. We don't
610 * support fallocate for non extent files. So we can update
611 * reserve space here.
614 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
615 ext4_da_update_reserve_space(inode
, retval
, 1);
621 if (unlikely(retval
!= map
->m_len
)) {
622 ext4_warning(inode
->i_sb
,
623 "ES len assertion failed for inode "
624 "%lu: retval %d != map->m_len %d",
625 inode
->i_ino
, retval
, map
->m_len
);
630 * If the extent has been zeroed out, we don't need to update
631 * extent status tree.
633 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
634 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
635 if (ext4_es_is_written(&es
))
638 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
639 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
640 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
641 ext4_find_delalloc_range(inode
, map
->m_lblk
,
642 map
->m_lblk
+ map
->m_len
- 1))
643 status
|= EXTENT_STATUS_DELAYED
;
644 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
645 map
->m_pblk
, status
);
651 up_write((&EXT4_I(inode
)->i_data_sem
));
652 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
653 ret
= check_block_validity(inode
, map
);
660 static void ext4_end_io_unwritten(struct buffer_head
*bh
, int uptodate
)
662 struct inode
*inode
= bh
->b_assoc_map
->host
;
663 /* XXX: breaks on 32-bit > 16GB. Is that even supported? */
664 loff_t offset
= (loff_t
)(uintptr_t)bh
->b_private
<< inode
->i_blkbits
;
668 WARN_ON(!buffer_unwritten(bh
));
669 err
= ext4_convert_unwritten_extents(NULL
, inode
, offset
, bh
->b_size
);
672 /* Maximum number of blocks we map for direct IO at once. */
673 #define DIO_MAX_BLOCKS 4096
675 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
676 struct buffer_head
*bh
, int flags
)
678 handle_t
*handle
= ext4_journal_current_handle();
679 struct ext4_map_blocks map
;
680 int ret
= 0, started
= 0;
683 if (ext4_has_inline_data(inode
))
687 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
689 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
690 /* Direct IO write... */
691 if (map
.m_len
> DIO_MAX_BLOCKS
)
692 map
.m_len
= DIO_MAX_BLOCKS
;
693 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
694 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
696 if (IS_ERR(handle
)) {
697 ret
= PTR_ERR(handle
);
703 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
705 ext4_io_end_t
*io_end
= ext4_inode_aio(inode
);
707 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
708 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
709 if (IS_DAX(inode
) && buffer_unwritten(bh
) && !io_end
) {
710 bh
->b_assoc_map
= inode
->i_mapping
;
711 bh
->b_private
= (void *)(unsigned long)iblock
;
712 bh
->b_end_io
= ext4_end_io_unwritten
;
714 if (io_end
&& io_end
->flag
& EXT4_IO_END_UNWRITTEN
)
715 set_buffer_defer_completion(bh
);
716 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
720 ext4_journal_stop(handle
);
724 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
725 struct buffer_head
*bh
, int create
)
727 return _ext4_get_block(inode
, iblock
, bh
,
728 create
? EXT4_GET_BLOCKS_CREATE
: 0);
732 * `handle' can be NULL if create is zero
734 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
735 ext4_lblk_t block
, int create
)
737 struct ext4_map_blocks map
;
738 struct buffer_head
*bh
;
741 J_ASSERT(handle
!= NULL
|| create
== 0);
745 err
= ext4_map_blocks(handle
, inode
, &map
,
746 create
? EXT4_GET_BLOCKS_CREATE
: 0);
749 return create
? ERR_PTR(-ENOSPC
) : NULL
;
753 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
755 return ERR_PTR(-ENOMEM
);
756 if (map
.m_flags
& EXT4_MAP_NEW
) {
757 J_ASSERT(create
!= 0);
758 J_ASSERT(handle
!= NULL
);
761 * Now that we do not always journal data, we should
762 * keep in mind whether this should always journal the
763 * new buffer as metadata. For now, regular file
764 * writes use ext4_get_block instead, so it's not a
768 BUFFER_TRACE(bh
, "call get_create_access");
769 err
= ext4_journal_get_create_access(handle
, bh
);
774 if (!buffer_uptodate(bh
)) {
775 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
776 set_buffer_uptodate(bh
);
779 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
780 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
784 BUFFER_TRACE(bh
, "not a new buffer");
791 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
792 ext4_lblk_t block
, int create
)
794 struct buffer_head
*bh
;
796 bh
= ext4_getblk(handle
, inode
, block
, create
);
799 if (!bh
|| buffer_uptodate(bh
))
801 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
803 if (buffer_uptodate(bh
))
806 return ERR_PTR(-EIO
);
809 int ext4_walk_page_buffers(handle_t
*handle
,
810 struct buffer_head
*head
,
814 int (*fn
)(handle_t
*handle
,
815 struct buffer_head
*bh
))
817 struct buffer_head
*bh
;
818 unsigned block_start
, block_end
;
819 unsigned blocksize
= head
->b_size
;
821 struct buffer_head
*next
;
823 for (bh
= head
, block_start
= 0;
824 ret
== 0 && (bh
!= head
|| !block_start
);
825 block_start
= block_end
, bh
= next
) {
826 next
= bh
->b_this_page
;
827 block_end
= block_start
+ blocksize
;
828 if (block_end
<= from
|| block_start
>= to
) {
829 if (partial
&& !buffer_uptodate(bh
))
833 err
= (*fn
)(handle
, bh
);
841 * To preserve ordering, it is essential that the hole instantiation and
842 * the data write be encapsulated in a single transaction. We cannot
843 * close off a transaction and start a new one between the ext4_get_block()
844 * and the commit_write(). So doing the jbd2_journal_start at the start of
845 * prepare_write() is the right place.
847 * Also, this function can nest inside ext4_writepage(). In that case, we
848 * *know* that ext4_writepage() has generated enough buffer credits to do the
849 * whole page. So we won't block on the journal in that case, which is good,
850 * because the caller may be PF_MEMALLOC.
852 * By accident, ext4 can be reentered when a transaction is open via
853 * quota file writes. If we were to commit the transaction while thus
854 * reentered, there can be a deadlock - we would be holding a quota
855 * lock, and the commit would never complete if another thread had a
856 * transaction open and was blocking on the quota lock - a ranking
859 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
860 * will _not_ run commit under these circumstances because handle->h_ref
861 * is elevated. We'll still have enough credits for the tiny quotafile
864 int do_journal_get_write_access(handle_t
*handle
,
865 struct buffer_head
*bh
)
867 int dirty
= buffer_dirty(bh
);
870 if (!buffer_mapped(bh
) || buffer_freed(bh
))
873 * __block_write_begin() could have dirtied some buffers. Clean
874 * the dirty bit as jbd2_journal_get_write_access() could complain
875 * otherwise about fs integrity issues. Setting of the dirty bit
876 * by __block_write_begin() isn't a real problem here as we clear
877 * the bit before releasing a page lock and thus writeback cannot
878 * ever write the buffer.
881 clear_buffer_dirty(bh
);
882 BUFFER_TRACE(bh
, "get write access");
883 ret
= ext4_journal_get_write_access(handle
, bh
);
885 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
889 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
890 struct buffer_head
*bh_result
, int create
);
891 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
892 loff_t pos
, unsigned len
, unsigned flags
,
893 struct page
**pagep
, void **fsdata
)
895 struct inode
*inode
= mapping
->host
;
896 int ret
, needed_blocks
;
903 trace_ext4_write_begin(inode
, pos
, len
, flags
);
905 * Reserve one block more for addition to orphan list in case
906 * we allocate blocks but write fails for some reason
908 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
909 index
= pos
>> PAGE_CACHE_SHIFT
;
910 from
= pos
& (PAGE_CACHE_SIZE
- 1);
913 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
914 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
923 * grab_cache_page_write_begin() can take a long time if the
924 * system is thrashing due to memory pressure, or if the page
925 * is being written back. So grab it first before we start
926 * the transaction handle. This also allows us to allocate
927 * the page (if needed) without using GFP_NOFS.
930 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
936 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
937 if (IS_ERR(handle
)) {
938 page_cache_release(page
);
939 return PTR_ERR(handle
);
943 if (page
->mapping
!= mapping
) {
944 /* The page got truncated from under us */
946 page_cache_release(page
);
947 ext4_journal_stop(handle
);
950 /* In case writeback began while the page was unlocked */
951 wait_for_stable_page(page
);
953 if (ext4_should_dioread_nolock(inode
))
954 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
956 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
958 if (!ret
&& ext4_should_journal_data(inode
)) {
959 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
961 do_journal_get_write_access
);
967 * __block_write_begin may have instantiated a few blocks
968 * outside i_size. Trim these off again. Don't need
969 * i_size_read because we hold i_mutex.
971 * Add inode to orphan list in case we crash before
974 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
975 ext4_orphan_add(handle
, inode
);
977 ext4_journal_stop(handle
);
978 if (pos
+ len
> inode
->i_size
) {
979 ext4_truncate_failed_write(inode
);
981 * If truncate failed early the inode might
982 * still be on the orphan list; we need to
983 * make sure the inode is removed from the
984 * orphan list in that case.
987 ext4_orphan_del(NULL
, inode
);
990 if (ret
== -ENOSPC
&&
991 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
993 page_cache_release(page
);
1000 /* For write_end() in data=journal mode */
1001 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1004 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1006 set_buffer_uptodate(bh
);
1007 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1008 clear_buffer_meta(bh
);
1009 clear_buffer_prio(bh
);
1014 * We need to pick up the new inode size which generic_commit_write gave us
1015 * `file' can be NULL - eg, when called from page_symlink().
1017 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1018 * buffers are managed internally.
1020 static int ext4_write_end(struct file
*file
,
1021 struct address_space
*mapping
,
1022 loff_t pos
, unsigned len
, unsigned copied
,
1023 struct page
*page
, void *fsdata
)
1025 handle_t
*handle
= ext4_journal_current_handle();
1026 struct inode
*inode
= mapping
->host
;
1028 int i_size_changed
= 0;
1030 trace_ext4_write_end(inode
, pos
, len
, copied
);
1031 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1032 ret
= ext4_jbd2_file_inode(handle
, inode
);
1035 page_cache_release(page
);
1040 if (ext4_has_inline_data(inode
)) {
1041 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1047 copied
= block_write_end(file
, mapping
, pos
,
1048 len
, copied
, page
, fsdata
);
1050 * it's important to update i_size while still holding page lock:
1051 * page writeout could otherwise come in and zero beyond i_size.
1053 i_size_changed
= ext4_update_inode_size(inode
, pos
+ copied
);
1055 page_cache_release(page
);
1058 * Don't mark the inode dirty under page lock. First, it unnecessarily
1059 * makes the holding time of page lock longer. Second, it forces lock
1060 * ordering of page lock and transaction start for journaling
1064 ext4_mark_inode_dirty(handle
, inode
);
1066 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1067 /* if we have allocated more blocks and copied
1068 * less. We will have blocks allocated outside
1069 * inode->i_size. So truncate them
1071 ext4_orphan_add(handle
, inode
);
1073 ret2
= ext4_journal_stop(handle
);
1077 if (pos
+ len
> inode
->i_size
) {
1078 ext4_truncate_failed_write(inode
);
1080 * If truncate failed early the inode might still be
1081 * on the orphan list; we need to make sure the inode
1082 * is removed from the orphan list in that case.
1085 ext4_orphan_del(NULL
, inode
);
1088 return ret
? ret
: copied
;
1091 static int ext4_journalled_write_end(struct file
*file
,
1092 struct address_space
*mapping
,
1093 loff_t pos
, unsigned len
, unsigned copied
,
1094 struct page
*page
, void *fsdata
)
1096 handle_t
*handle
= ext4_journal_current_handle();
1097 struct inode
*inode
= mapping
->host
;
1101 int size_changed
= 0;
1103 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1104 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1107 BUG_ON(!ext4_handle_valid(handle
));
1109 if (ext4_has_inline_data(inode
))
1110 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1114 if (!PageUptodate(page
))
1116 page_zero_new_buffers(page
, from
+copied
, to
);
1119 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1120 to
, &partial
, write_end_fn
);
1122 SetPageUptodate(page
);
1124 size_changed
= ext4_update_inode_size(inode
, pos
+ copied
);
1125 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1126 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1128 page_cache_release(page
);
1131 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1136 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1137 /* if we have allocated more blocks and copied
1138 * less. We will have blocks allocated outside
1139 * inode->i_size. So truncate them
1141 ext4_orphan_add(handle
, inode
);
1143 ret2
= ext4_journal_stop(handle
);
1146 if (pos
+ len
> inode
->i_size
) {
1147 ext4_truncate_failed_write(inode
);
1149 * If truncate failed early the inode might still be
1150 * on the orphan list; we need to make sure the inode
1151 * is removed from the orphan list in that case.
1154 ext4_orphan_del(NULL
, inode
);
1157 return ret
? ret
: copied
;
1161 * Reserve a single cluster located at lblock
1163 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1165 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1166 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1167 unsigned int md_needed
;
1171 * We will charge metadata quota at writeout time; this saves
1172 * us from metadata over-estimation, though we may go over by
1173 * a small amount in the end. Here we just reserve for data.
1175 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1180 * recalculate the amount of metadata blocks to reserve
1181 * in order to allocate nrblocks
1182 * worse case is one extent per block
1184 spin_lock(&ei
->i_block_reservation_lock
);
1186 * ext4_calc_metadata_amount() has side effects, which we have
1187 * to be prepared undo if we fail to claim space.
1190 trace_ext4_da_reserve_space(inode
, 0);
1192 if (ext4_claim_free_clusters(sbi
, 1, 0)) {
1193 spin_unlock(&ei
->i_block_reservation_lock
);
1194 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1197 ei
->i_reserved_data_blocks
++;
1198 spin_unlock(&ei
->i_block_reservation_lock
);
1200 return 0; /* success */
1203 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1205 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1206 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1209 return; /* Nothing to release, exit */
1211 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1213 trace_ext4_da_release_space(inode
, to_free
);
1214 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1216 * if there aren't enough reserved blocks, then the
1217 * counter is messed up somewhere. Since this
1218 * function is called from invalidate page, it's
1219 * harmless to return without any action.
1221 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1222 "ino %lu, to_free %d with only %d reserved "
1223 "data blocks", inode
->i_ino
, to_free
,
1224 ei
->i_reserved_data_blocks
);
1226 to_free
= ei
->i_reserved_data_blocks
;
1228 ei
->i_reserved_data_blocks
-= to_free
;
1230 /* update fs dirty data blocks counter */
1231 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1233 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1235 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1238 static void ext4_da_page_release_reservation(struct page
*page
,
1239 unsigned int offset
,
1240 unsigned int length
)
1243 struct buffer_head
*head
, *bh
;
1244 unsigned int curr_off
= 0;
1245 struct inode
*inode
= page
->mapping
->host
;
1246 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1247 unsigned int stop
= offset
+ length
;
1251 BUG_ON(stop
> PAGE_CACHE_SIZE
|| stop
< length
);
1253 head
= page_buffers(page
);
1256 unsigned int next_off
= curr_off
+ bh
->b_size
;
1258 if (next_off
> stop
)
1261 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1263 clear_buffer_delay(bh
);
1265 curr_off
= next_off
;
1266 } while ((bh
= bh
->b_this_page
) != head
);
1269 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1270 ext4_es_remove_extent(inode
, lblk
, to_release
);
1273 /* If we have released all the blocks belonging to a cluster, then we
1274 * need to release the reserved space for that cluster. */
1275 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1276 while (num_clusters
> 0) {
1277 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1278 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1279 if (sbi
->s_cluster_ratio
== 1 ||
1280 !ext4_find_delalloc_cluster(inode
, lblk
))
1281 ext4_da_release_space(inode
, 1);
1288 * Delayed allocation stuff
1291 struct mpage_da_data
{
1292 struct inode
*inode
;
1293 struct writeback_control
*wbc
;
1295 pgoff_t first_page
; /* The first page to write */
1296 pgoff_t next_page
; /* Current page to examine */
1297 pgoff_t last_page
; /* Last page to examine */
1299 * Extent to map - this can be after first_page because that can be
1300 * fully mapped. We somewhat abuse m_flags to store whether the extent
1301 * is delalloc or unwritten.
1303 struct ext4_map_blocks map
;
1304 struct ext4_io_submit io_submit
; /* IO submission data */
1307 static void mpage_release_unused_pages(struct mpage_da_data
*mpd
,
1312 struct pagevec pvec
;
1313 struct inode
*inode
= mpd
->inode
;
1314 struct address_space
*mapping
= inode
->i_mapping
;
1316 /* This is necessary when next_page == 0. */
1317 if (mpd
->first_page
>= mpd
->next_page
)
1320 index
= mpd
->first_page
;
1321 end
= mpd
->next_page
- 1;
1323 ext4_lblk_t start
, last
;
1324 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1325 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1326 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1329 pagevec_init(&pvec
, 0);
1330 while (index
<= end
) {
1331 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1334 for (i
= 0; i
< nr_pages
; i
++) {
1335 struct page
*page
= pvec
.pages
[i
];
1336 if (page
->index
> end
)
1338 BUG_ON(!PageLocked(page
));
1339 BUG_ON(PageWriteback(page
));
1341 block_invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
1342 ClearPageUptodate(page
);
1346 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1347 pagevec_release(&pvec
);
1351 static void ext4_print_free_blocks(struct inode
*inode
)
1353 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1354 struct super_block
*sb
= inode
->i_sb
;
1355 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1357 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1358 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1359 ext4_count_free_clusters(sb
)));
1360 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1361 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1362 (long long) EXT4_C2B(EXT4_SB(sb
),
1363 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1364 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1365 (long long) EXT4_C2B(EXT4_SB(sb
),
1366 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1367 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1368 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1369 ei
->i_reserved_data_blocks
);
1373 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1375 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1379 * This function is grabs code from the very beginning of
1380 * ext4_map_blocks, but assumes that the caller is from delayed write
1381 * time. This function looks up the requested blocks and sets the
1382 * buffer delay bit under the protection of i_data_sem.
1384 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1385 struct ext4_map_blocks
*map
,
1386 struct buffer_head
*bh
)
1388 struct extent_status es
;
1390 sector_t invalid_block
= ~((sector_t
) 0xffff);
1391 #ifdef ES_AGGRESSIVE_TEST
1392 struct ext4_map_blocks orig_map
;
1394 memcpy(&orig_map
, map
, sizeof(*map
));
1397 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1401 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1402 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1403 (unsigned long) map
->m_lblk
);
1405 /* Lookup extent status tree firstly */
1406 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1407 if (ext4_es_is_hole(&es
)) {
1409 down_read(&EXT4_I(inode
)->i_data_sem
);
1414 * Delayed extent could be allocated by fallocate.
1415 * So we need to check it.
1417 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1418 map_bh(bh
, inode
->i_sb
, invalid_block
);
1420 set_buffer_delay(bh
);
1424 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1425 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1426 if (retval
> map
->m_len
)
1427 retval
= map
->m_len
;
1428 map
->m_len
= retval
;
1429 if (ext4_es_is_written(&es
))
1430 map
->m_flags
|= EXT4_MAP_MAPPED
;
1431 else if (ext4_es_is_unwritten(&es
))
1432 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1436 #ifdef ES_AGGRESSIVE_TEST
1437 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1443 * Try to see if we can get the block without requesting a new
1444 * file system block.
1446 down_read(&EXT4_I(inode
)->i_data_sem
);
1447 if (ext4_has_inline_data(inode
))
1449 else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1450 retval
= ext4_ext_map_blocks(NULL
, inode
, map
, 0);
1452 retval
= ext4_ind_map_blocks(NULL
, inode
, map
, 0);
1458 * XXX: __block_prepare_write() unmaps passed block,
1462 * If the block was allocated from previously allocated cluster,
1463 * then we don't need to reserve it again. However we still need
1464 * to reserve metadata for every block we're going to write.
1466 if (EXT4_SB(inode
->i_sb
)->s_cluster_ratio
<= 1 ||
1467 !ext4_find_delalloc_cluster(inode
, map
->m_lblk
)) {
1468 ret
= ext4_da_reserve_space(inode
, iblock
);
1470 /* not enough space to reserve */
1476 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1477 ~0, EXTENT_STATUS_DELAYED
);
1483 map_bh(bh
, inode
->i_sb
, invalid_block
);
1485 set_buffer_delay(bh
);
1486 } else if (retval
> 0) {
1488 unsigned int status
;
1490 if (unlikely(retval
!= map
->m_len
)) {
1491 ext4_warning(inode
->i_sb
,
1492 "ES len assertion failed for inode "
1493 "%lu: retval %d != map->m_len %d",
1494 inode
->i_ino
, retval
, map
->m_len
);
1498 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
1499 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
1500 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1501 map
->m_pblk
, status
);
1507 up_read((&EXT4_I(inode
)->i_data_sem
));
1513 * This is a special get_block_t callback which is used by
1514 * ext4_da_write_begin(). It will either return mapped block or
1515 * reserve space for a single block.
1517 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
1518 * We also have b_blocknr = -1 and b_bdev initialized properly
1520 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
1521 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
1522 * initialized properly.
1524 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
1525 struct buffer_head
*bh
, int create
)
1527 struct ext4_map_blocks map
;
1530 BUG_ON(create
== 0);
1531 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
1533 map
.m_lblk
= iblock
;
1537 * first, we need to know whether the block is allocated already
1538 * preallocated blocks are unmapped but should treated
1539 * the same as allocated blocks.
1541 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
1545 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
1546 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
1548 if (buffer_unwritten(bh
)) {
1549 /* A delayed write to unwritten bh should be marked
1550 * new and mapped. Mapped ensures that we don't do
1551 * get_block multiple times when we write to the same
1552 * offset and new ensures that we do proper zero out
1553 * for partial write.
1556 set_buffer_mapped(bh
);
1561 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1567 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1573 static int __ext4_journalled_writepage(struct page
*page
,
1576 struct address_space
*mapping
= page
->mapping
;
1577 struct inode
*inode
= mapping
->host
;
1578 struct buffer_head
*page_bufs
= NULL
;
1579 handle_t
*handle
= NULL
;
1580 int ret
= 0, err
= 0;
1581 int inline_data
= ext4_has_inline_data(inode
);
1582 struct buffer_head
*inode_bh
= NULL
;
1584 ClearPageChecked(page
);
1587 BUG_ON(page
->index
!= 0);
1588 BUG_ON(len
> ext4_get_max_inline_size(inode
));
1589 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
1590 if (inode_bh
== NULL
)
1593 page_bufs
= page_buffers(page
);
1598 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
1601 /* As soon as we unlock the page, it can go away, but we have
1602 * references to buffers so we are safe */
1605 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
1606 ext4_writepage_trans_blocks(inode
));
1607 if (IS_ERR(handle
)) {
1608 ret
= PTR_ERR(handle
);
1612 BUG_ON(!ext4_handle_valid(handle
));
1615 BUFFER_TRACE(inode_bh
, "get write access");
1616 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
1618 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
1621 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1622 do_journal_get_write_access
);
1624 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1629 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1630 err
= ext4_journal_stop(handle
);
1634 if (!ext4_has_inline_data(inode
))
1635 ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
,
1637 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1644 * Note that we don't need to start a transaction unless we're journaling data
1645 * because we should have holes filled from ext4_page_mkwrite(). We even don't
1646 * need to file the inode to the transaction's list in ordered mode because if
1647 * we are writing back data added by write(), the inode is already there and if
1648 * we are writing back data modified via mmap(), no one guarantees in which
1649 * transaction the data will hit the disk. In case we are journaling data, we
1650 * cannot start transaction directly because transaction start ranks above page
1651 * lock so we have to do some magic.
1653 * This function can get called via...
1654 * - ext4_writepages after taking page lock (have journal handle)
1655 * - journal_submit_inode_data_buffers (no journal handle)
1656 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
1657 * - grab_page_cache when doing write_begin (have journal handle)
1659 * We don't do any block allocation in this function. If we have page with
1660 * multiple blocks we need to write those buffer_heads that are mapped. This
1661 * is important for mmaped based write. So if we do with blocksize 1K
1662 * truncate(f, 1024);
1663 * a = mmap(f, 0, 4096);
1665 * truncate(f, 4096);
1666 * we have in the page first buffer_head mapped via page_mkwrite call back
1667 * but other buffer_heads would be unmapped but dirty (dirty done via the
1668 * do_wp_page). So writepage should write the first block. If we modify
1669 * the mmap area beyond 1024 we will again get a page_fault and the
1670 * page_mkwrite callback will do the block allocation and mark the
1671 * buffer_heads mapped.
1673 * We redirty the page if we have any buffer_heads that is either delay or
1674 * unwritten in the page.
1676 * We can get recursively called as show below.
1678 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1681 * But since we don't do any block allocation we should not deadlock.
1682 * Page also have the dirty flag cleared so we don't get recurive page_lock.
1684 static int ext4_writepage(struct page
*page
,
1685 struct writeback_control
*wbc
)
1690 struct buffer_head
*page_bufs
= NULL
;
1691 struct inode
*inode
= page
->mapping
->host
;
1692 struct ext4_io_submit io_submit
;
1693 bool keep_towrite
= false;
1695 trace_ext4_writepage(page
);
1696 size
= i_size_read(inode
);
1697 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1698 len
= size
& ~PAGE_CACHE_MASK
;
1700 len
= PAGE_CACHE_SIZE
;
1702 page_bufs
= page_buffers(page
);
1704 * We cannot do block allocation or other extent handling in this
1705 * function. If there are buffers needing that, we have to redirty
1706 * the page. But we may reach here when we do a journal commit via
1707 * journal_submit_inode_data_buffers() and in that case we must write
1708 * allocated buffers to achieve data=ordered mode guarantees.
1710 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
1711 ext4_bh_delay_or_unwritten
)) {
1712 redirty_page_for_writepage(wbc
, page
);
1713 if (current
->flags
& PF_MEMALLOC
) {
1715 * For memory cleaning there's no point in writing only
1716 * some buffers. So just bail out. Warn if we came here
1717 * from direct reclaim.
1719 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
1724 keep_towrite
= true;
1727 if (PageChecked(page
) && ext4_should_journal_data(inode
))
1729 * It's mmapped pagecache. Add buffers and journal it. There
1730 * doesn't seem much point in redirtying the page here.
1732 return __ext4_journalled_writepage(page
, len
);
1734 ext4_io_submit_init(&io_submit
, wbc
);
1735 io_submit
.io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
1736 if (!io_submit
.io_end
) {
1737 redirty_page_for_writepage(wbc
, page
);
1741 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
, keep_towrite
);
1742 ext4_io_submit(&io_submit
);
1743 /* Drop io_end reference we got from init */
1744 ext4_put_io_end_defer(io_submit
.io_end
);
1748 static int mpage_submit_page(struct mpage_da_data
*mpd
, struct page
*page
)
1751 loff_t size
= i_size_read(mpd
->inode
);
1754 BUG_ON(page
->index
!= mpd
->first_page
);
1755 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1756 len
= size
& ~PAGE_CACHE_MASK
;
1758 len
= PAGE_CACHE_SIZE
;
1759 clear_page_dirty_for_io(page
);
1760 err
= ext4_bio_write_page(&mpd
->io_submit
, page
, len
, mpd
->wbc
, false);
1762 mpd
->wbc
->nr_to_write
--;
1768 #define BH_FLAGS ((1 << BH_Unwritten) | (1 << BH_Delay))
1771 * mballoc gives us at most this number of blocks...
1772 * XXX: That seems to be only a limitation of ext4_mb_normalize_request().
1773 * The rest of mballoc seems to handle chunks up to full group size.
1775 #define MAX_WRITEPAGES_EXTENT_LEN 2048
1778 * mpage_add_bh_to_extent - try to add bh to extent of blocks to map
1780 * @mpd - extent of blocks
1781 * @lblk - logical number of the block in the file
1782 * @bh - buffer head we want to add to the extent
1784 * The function is used to collect contig. blocks in the same state. If the
1785 * buffer doesn't require mapping for writeback and we haven't started the
1786 * extent of buffers to map yet, the function returns 'true' immediately - the
1787 * caller can write the buffer right away. Otherwise the function returns true
1788 * if the block has been added to the extent, false if the block couldn't be
1791 static bool mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, ext4_lblk_t lblk
,
1792 struct buffer_head
*bh
)
1794 struct ext4_map_blocks
*map
= &mpd
->map
;
1796 /* Buffer that doesn't need mapping for writeback? */
1797 if (!buffer_dirty(bh
) || !buffer_mapped(bh
) ||
1798 (!buffer_delay(bh
) && !buffer_unwritten(bh
))) {
1799 /* So far no extent to map => we write the buffer right away */
1800 if (map
->m_len
== 0)
1805 /* First block in the extent? */
1806 if (map
->m_len
== 0) {
1809 map
->m_flags
= bh
->b_state
& BH_FLAGS
;
1813 /* Don't go larger than mballoc is willing to allocate */
1814 if (map
->m_len
>= MAX_WRITEPAGES_EXTENT_LEN
)
1817 /* Can we merge the block to our big extent? */
1818 if (lblk
== map
->m_lblk
+ map
->m_len
&&
1819 (bh
->b_state
& BH_FLAGS
) == map
->m_flags
) {
1827 * mpage_process_page_bufs - submit page buffers for IO or add them to extent
1829 * @mpd - extent of blocks for mapping
1830 * @head - the first buffer in the page
1831 * @bh - buffer we should start processing from
1832 * @lblk - logical number of the block in the file corresponding to @bh
1834 * Walk through page buffers from @bh upto @head (exclusive) and either submit
1835 * the page for IO if all buffers in this page were mapped and there's no
1836 * accumulated extent of buffers to map or add buffers in the page to the
1837 * extent of buffers to map. The function returns 1 if the caller can continue
1838 * by processing the next page, 0 if it should stop adding buffers to the
1839 * extent to map because we cannot extend it anymore. It can also return value
1840 * < 0 in case of error during IO submission.
1842 static int mpage_process_page_bufs(struct mpage_da_data
*mpd
,
1843 struct buffer_head
*head
,
1844 struct buffer_head
*bh
,
1847 struct inode
*inode
= mpd
->inode
;
1849 ext4_lblk_t blocks
= (i_size_read(inode
) + (1 << inode
->i_blkbits
) - 1)
1850 >> inode
->i_blkbits
;
1853 BUG_ON(buffer_locked(bh
));
1855 if (lblk
>= blocks
|| !mpage_add_bh_to_extent(mpd
, lblk
, bh
)) {
1856 /* Found extent to map? */
1859 /* Everything mapped so far and we hit EOF */
1862 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
1863 /* So far everything mapped? Submit the page for IO. */
1864 if (mpd
->map
.m_len
== 0) {
1865 err
= mpage_submit_page(mpd
, head
->b_page
);
1869 return lblk
< blocks
;
1873 * mpage_map_buffers - update buffers corresponding to changed extent and
1874 * submit fully mapped pages for IO
1876 * @mpd - description of extent to map, on return next extent to map
1878 * Scan buffers corresponding to changed extent (we expect corresponding pages
1879 * to be already locked) and update buffer state according to new extent state.
1880 * We map delalloc buffers to their physical location, clear unwritten bits,
1881 * and mark buffers as uninit when we perform writes to unwritten extents
1882 * and do extent conversion after IO is finished. If the last page is not fully
1883 * mapped, we update @map to the next extent in the last page that needs
1884 * mapping. Otherwise we submit the page for IO.
1886 static int mpage_map_and_submit_buffers(struct mpage_da_data
*mpd
)
1888 struct pagevec pvec
;
1890 struct inode
*inode
= mpd
->inode
;
1891 struct buffer_head
*head
, *bh
;
1892 int bpp_bits
= PAGE_CACHE_SHIFT
- inode
->i_blkbits
;
1898 start
= mpd
->map
.m_lblk
>> bpp_bits
;
1899 end
= (mpd
->map
.m_lblk
+ mpd
->map
.m_len
- 1) >> bpp_bits
;
1900 lblk
= start
<< bpp_bits
;
1901 pblock
= mpd
->map
.m_pblk
;
1903 pagevec_init(&pvec
, 0);
1904 while (start
<= end
) {
1905 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, start
,
1909 for (i
= 0; i
< nr_pages
; i
++) {
1910 struct page
*page
= pvec
.pages
[i
];
1912 if (page
->index
> end
)
1914 /* Up to 'end' pages must be contiguous */
1915 BUG_ON(page
->index
!= start
);
1916 bh
= head
= page_buffers(page
);
1918 if (lblk
< mpd
->map
.m_lblk
)
1920 if (lblk
>= mpd
->map
.m_lblk
+ mpd
->map
.m_len
) {
1922 * Buffer after end of mapped extent.
1923 * Find next buffer in the page to map.
1926 mpd
->map
.m_flags
= 0;
1928 * FIXME: If dioread_nolock supports
1929 * blocksize < pagesize, we need to make
1930 * sure we add size mapped so far to
1931 * io_end->size as the following call
1932 * can submit the page for IO.
1934 err
= mpage_process_page_bufs(mpd
, head
,
1936 pagevec_release(&pvec
);
1941 if (buffer_delay(bh
)) {
1942 clear_buffer_delay(bh
);
1943 bh
->b_blocknr
= pblock
++;
1945 clear_buffer_unwritten(bh
);
1946 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
1949 * FIXME: This is going to break if dioread_nolock
1950 * supports blocksize < pagesize as we will try to
1951 * convert potentially unmapped parts of inode.
1953 mpd
->io_submit
.io_end
->size
+= PAGE_CACHE_SIZE
;
1954 /* Page fully mapped - let IO run! */
1955 err
= mpage_submit_page(mpd
, page
);
1957 pagevec_release(&pvec
);
1962 pagevec_release(&pvec
);
1964 /* Extent fully mapped and matches with page boundary. We are done. */
1966 mpd
->map
.m_flags
= 0;
1970 static int mpage_map_one_extent(handle_t
*handle
, struct mpage_da_data
*mpd
)
1972 struct inode
*inode
= mpd
->inode
;
1973 struct ext4_map_blocks
*map
= &mpd
->map
;
1974 int get_blocks_flags
;
1975 int err
, dioread_nolock
;
1977 trace_ext4_da_write_pages_extent(inode
, map
);
1979 * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
1980 * to convert an unwritten extent to be initialized (in the case
1981 * where we have written into one or more preallocated blocks). It is
1982 * possible that we're going to need more metadata blocks than
1983 * previously reserved. However we must not fail because we're in
1984 * writeback and there is nothing we can do about it so it might result
1985 * in data loss. So use reserved blocks to allocate metadata if
1988 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if
1989 * the blocks in question are delalloc blocks. This indicates
1990 * that the blocks and quotas has already been checked when
1991 * the data was copied into the page cache.
1993 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
1994 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
1995 dioread_nolock
= ext4_should_dioread_nolock(inode
);
1997 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
1998 if (map
->m_flags
& (1 << BH_Delay
))
1999 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
2001 err
= ext4_map_blocks(handle
, inode
, map
, get_blocks_flags
);
2004 if (dioread_nolock
&& (map
->m_flags
& EXT4_MAP_UNWRITTEN
)) {
2005 if (!mpd
->io_submit
.io_end
->handle
&&
2006 ext4_handle_valid(handle
)) {
2007 mpd
->io_submit
.io_end
->handle
= handle
->h_rsv_handle
;
2008 handle
->h_rsv_handle
= NULL
;
2010 ext4_set_io_unwritten_flag(inode
, mpd
->io_submit
.io_end
);
2013 BUG_ON(map
->m_len
== 0);
2014 if (map
->m_flags
& EXT4_MAP_NEW
) {
2015 struct block_device
*bdev
= inode
->i_sb
->s_bdev
;
2018 for (i
= 0; i
< map
->m_len
; i
++)
2019 unmap_underlying_metadata(bdev
, map
->m_pblk
+ i
);
2025 * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
2026 * mpd->len and submit pages underlying it for IO
2028 * @handle - handle for journal operations
2029 * @mpd - extent to map
2030 * @give_up_on_write - we set this to true iff there is a fatal error and there
2031 * is no hope of writing the data. The caller should discard
2032 * dirty pages to avoid infinite loops.
2034 * The function maps extent starting at mpd->lblk of length mpd->len. If it is
2035 * delayed, blocks are allocated, if it is unwritten, we may need to convert
2036 * them to initialized or split the described range from larger unwritten
2037 * extent. Note that we need not map all the described range since allocation
2038 * can return less blocks or the range is covered by more unwritten extents. We
2039 * cannot map more because we are limited by reserved transaction credits. On
2040 * the other hand we always make sure that the last touched page is fully
2041 * mapped so that it can be written out (and thus forward progress is
2042 * guaranteed). After mapping we submit all mapped pages for IO.
2044 static int mpage_map_and_submit_extent(handle_t
*handle
,
2045 struct mpage_da_data
*mpd
,
2046 bool *give_up_on_write
)
2048 struct inode
*inode
= mpd
->inode
;
2049 struct ext4_map_blocks
*map
= &mpd
->map
;
2054 mpd
->io_submit
.io_end
->offset
=
2055 ((loff_t
)map
->m_lblk
) << inode
->i_blkbits
;
2057 err
= mpage_map_one_extent(handle
, mpd
);
2059 struct super_block
*sb
= inode
->i_sb
;
2061 if (EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)
2062 goto invalidate_dirty_pages
;
2064 * Let the uper layers retry transient errors.
2065 * In the case of ENOSPC, if ext4_count_free_blocks()
2066 * is non-zero, a commit should free up blocks.
2068 if ((err
== -ENOMEM
) ||
2069 (err
== -ENOSPC
&& ext4_count_free_clusters(sb
))) {
2071 goto update_disksize
;
2074 ext4_msg(sb
, KERN_CRIT
,
2075 "Delayed block allocation failed for "
2076 "inode %lu at logical offset %llu with"
2077 " max blocks %u with error %d",
2079 (unsigned long long)map
->m_lblk
,
2080 (unsigned)map
->m_len
, -err
);
2081 ext4_msg(sb
, KERN_CRIT
,
2082 "This should not happen!! Data will "
2085 ext4_print_free_blocks(inode
);
2086 invalidate_dirty_pages
:
2087 *give_up_on_write
= true;
2092 * Update buffer state, submit mapped pages, and get us new
2095 err
= mpage_map_and_submit_buffers(mpd
);
2097 goto update_disksize
;
2098 } while (map
->m_len
);
2102 * Update on-disk size after IO is submitted. Races with
2103 * truncate are avoided by checking i_size under i_data_sem.
2105 disksize
= ((loff_t
)mpd
->first_page
) << PAGE_CACHE_SHIFT
;
2106 if (disksize
> EXT4_I(inode
)->i_disksize
) {
2110 down_write(&EXT4_I(inode
)->i_data_sem
);
2111 i_size
= i_size_read(inode
);
2112 if (disksize
> i_size
)
2114 if (disksize
> EXT4_I(inode
)->i_disksize
)
2115 EXT4_I(inode
)->i_disksize
= disksize
;
2116 err2
= ext4_mark_inode_dirty(handle
, inode
);
2117 up_write(&EXT4_I(inode
)->i_data_sem
);
2119 ext4_error(inode
->i_sb
,
2120 "Failed to mark inode %lu dirty",
2129 * Calculate the total number of credits to reserve for one writepages
2130 * iteration. This is called from ext4_writepages(). We map an extent of
2131 * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
2132 * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
2133 * bpp - 1 blocks in bpp different extents.
2135 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2137 int bpp
= ext4_journal_blocks_per_page(inode
);
2139 return ext4_meta_trans_blocks(inode
,
2140 MAX_WRITEPAGES_EXTENT_LEN
+ bpp
- 1, bpp
);
2144 * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
2145 * and underlying extent to map
2147 * @mpd - where to look for pages
2149 * Walk dirty pages in the mapping. If they are fully mapped, submit them for
2150 * IO immediately. When we find a page which isn't mapped we start accumulating
2151 * extent of buffers underlying these pages that needs mapping (formed by
2152 * either delayed or unwritten buffers). We also lock the pages containing
2153 * these buffers. The extent found is returned in @mpd structure (starting at
2154 * mpd->lblk with length mpd->len blocks).
2156 * Note that this function can attach bios to one io_end structure which are
2157 * neither logically nor physically contiguous. Although it may seem as an
2158 * unnecessary complication, it is actually inevitable in blocksize < pagesize
2159 * case as we need to track IO to all buffers underlying a page in one io_end.
2161 static int mpage_prepare_extent_to_map(struct mpage_da_data
*mpd
)
2163 struct address_space
*mapping
= mpd
->inode
->i_mapping
;
2164 struct pagevec pvec
;
2165 unsigned int nr_pages
;
2166 long left
= mpd
->wbc
->nr_to_write
;
2167 pgoff_t index
= mpd
->first_page
;
2168 pgoff_t end
= mpd
->last_page
;
2171 int blkbits
= mpd
->inode
->i_blkbits
;
2173 struct buffer_head
*head
;
2175 if (mpd
->wbc
->sync_mode
== WB_SYNC_ALL
|| mpd
->wbc
->tagged_writepages
)
2176 tag
= PAGECACHE_TAG_TOWRITE
;
2178 tag
= PAGECACHE_TAG_DIRTY
;
2180 pagevec_init(&pvec
, 0);
2182 mpd
->next_page
= index
;
2183 while (index
<= end
) {
2184 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2185 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2189 for (i
= 0; i
< nr_pages
; i
++) {
2190 struct page
*page
= pvec
.pages
[i
];
2193 * At this point, the page may be truncated or
2194 * invalidated (changing page->mapping to NULL), or
2195 * even swizzled back from swapper_space to tmpfs file
2196 * mapping. However, page->index will not change
2197 * because we have a reference on the page.
2199 if (page
->index
> end
)
2203 * Accumulated enough dirty pages? This doesn't apply
2204 * to WB_SYNC_ALL mode. For integrity sync we have to
2205 * keep going because someone may be concurrently
2206 * dirtying pages, and we might have synced a lot of
2207 * newly appeared dirty pages, but have not synced all
2208 * of the old dirty pages.
2210 if (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
&& left
<= 0)
2213 /* If we can't merge this page, we are done. */
2214 if (mpd
->map
.m_len
> 0 && mpd
->next_page
!= page
->index
)
2219 * If the page is no longer dirty, or its mapping no
2220 * longer corresponds to inode we are writing (which
2221 * means it has been truncated or invalidated), or the
2222 * page is already under writeback and we are not doing
2223 * a data integrity writeback, skip the page
2225 if (!PageDirty(page
) ||
2226 (PageWriteback(page
) &&
2227 (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2228 unlikely(page
->mapping
!= mapping
)) {
2233 wait_on_page_writeback(page
);
2234 BUG_ON(PageWriteback(page
));
2236 if (mpd
->map
.m_len
== 0)
2237 mpd
->first_page
= page
->index
;
2238 mpd
->next_page
= page
->index
+ 1;
2239 /* Add all dirty buffers to mpd */
2240 lblk
= ((ext4_lblk_t
)page
->index
) <<
2241 (PAGE_CACHE_SHIFT
- blkbits
);
2242 head
= page_buffers(page
);
2243 err
= mpage_process_page_bufs(mpd
, head
, head
, lblk
);
2249 pagevec_release(&pvec
);
2254 pagevec_release(&pvec
);
2258 static int __writepage(struct page
*page
, struct writeback_control
*wbc
,
2261 struct address_space
*mapping
= data
;
2262 int ret
= ext4_writepage(page
, wbc
);
2263 mapping_set_error(mapping
, ret
);
2267 static int ext4_writepages(struct address_space
*mapping
,
2268 struct writeback_control
*wbc
)
2270 pgoff_t writeback_index
= 0;
2271 long nr_to_write
= wbc
->nr_to_write
;
2272 int range_whole
= 0;
2274 handle_t
*handle
= NULL
;
2275 struct mpage_da_data mpd
;
2276 struct inode
*inode
= mapping
->host
;
2277 int needed_blocks
, rsv_blocks
= 0, ret
= 0;
2278 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2280 struct blk_plug plug
;
2281 bool give_up_on_write
= false;
2283 trace_ext4_writepages(inode
, wbc
);
2286 * No pages to write? This is mainly a kludge to avoid starting
2287 * a transaction for special inodes like journal inode on last iput()
2288 * because that could violate lock ordering on umount
2290 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2291 goto out_writepages
;
2293 if (ext4_should_journal_data(inode
)) {
2294 struct blk_plug plug
;
2296 blk_start_plug(&plug
);
2297 ret
= write_cache_pages(mapping
, wbc
, __writepage
, mapping
);
2298 blk_finish_plug(&plug
);
2299 goto out_writepages
;
2303 * If the filesystem has aborted, it is read-only, so return
2304 * right away instead of dumping stack traces later on that
2305 * will obscure the real source of the problem. We test
2306 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2307 * the latter could be true if the filesystem is mounted
2308 * read-only, and in that case, ext4_writepages should
2309 * *never* be called, so if that ever happens, we would want
2312 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
2314 goto out_writepages
;
2317 if (ext4_should_dioread_nolock(inode
)) {
2319 * We may need to convert up to one extent per block in
2320 * the page and we may dirty the inode.
2322 rsv_blocks
= 1 + (PAGE_CACHE_SIZE
>> inode
->i_blkbits
);
2326 * If we have inline data and arrive here, it means that
2327 * we will soon create the block for the 1st page, so
2328 * we'd better clear the inline data here.
2330 if (ext4_has_inline_data(inode
)) {
2331 /* Just inode will be modified... */
2332 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
2333 if (IS_ERR(handle
)) {
2334 ret
= PTR_ERR(handle
);
2335 goto out_writepages
;
2337 BUG_ON(ext4_test_inode_state(inode
,
2338 EXT4_STATE_MAY_INLINE_DATA
));
2339 ext4_destroy_inline_data(handle
, inode
);
2340 ext4_journal_stop(handle
);
2343 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2346 if (wbc
->range_cyclic
) {
2347 writeback_index
= mapping
->writeback_index
;
2348 if (writeback_index
)
2350 mpd
.first_page
= writeback_index
;
2353 mpd
.first_page
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2354 mpd
.last_page
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2359 ext4_io_submit_init(&mpd
.io_submit
, wbc
);
2361 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2362 tag_pages_for_writeback(mapping
, mpd
.first_page
, mpd
.last_page
);
2364 blk_start_plug(&plug
);
2365 while (!done
&& mpd
.first_page
<= mpd
.last_page
) {
2366 /* For each extent of pages we use new io_end */
2367 mpd
.io_submit
.io_end
= ext4_init_io_end(inode
, GFP_KERNEL
);
2368 if (!mpd
.io_submit
.io_end
) {
2374 * We have two constraints: We find one extent to map and we
2375 * must always write out whole page (makes a difference when
2376 * blocksize < pagesize) so that we don't block on IO when we
2377 * try to write out the rest of the page. Journalled mode is
2378 * not supported by delalloc.
2380 BUG_ON(ext4_should_journal_data(inode
));
2381 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2383 /* start a new transaction */
2384 handle
= ext4_journal_start_with_reserve(inode
,
2385 EXT4_HT_WRITE_PAGE
, needed_blocks
, rsv_blocks
);
2386 if (IS_ERR(handle
)) {
2387 ret
= PTR_ERR(handle
);
2388 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2389 "%ld pages, ino %lu; err %d", __func__
,
2390 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2391 /* Release allocated io_end */
2392 ext4_put_io_end(mpd
.io_submit
.io_end
);
2396 trace_ext4_da_write_pages(inode
, mpd
.first_page
, mpd
.wbc
);
2397 ret
= mpage_prepare_extent_to_map(&mpd
);
2400 ret
= mpage_map_and_submit_extent(handle
, &mpd
,
2404 * We scanned the whole range (or exhausted
2405 * nr_to_write), submitted what was mapped and
2406 * didn't find anything needing mapping. We are
2412 ext4_journal_stop(handle
);
2413 /* Submit prepared bio */
2414 ext4_io_submit(&mpd
.io_submit
);
2415 /* Unlock pages we didn't use */
2416 mpage_release_unused_pages(&mpd
, give_up_on_write
);
2417 /* Drop our io_end reference we got from init */
2418 ext4_put_io_end(mpd
.io_submit
.io_end
);
2420 if (ret
== -ENOSPC
&& sbi
->s_journal
) {
2422 * Commit the transaction which would
2423 * free blocks released in the transaction
2426 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2430 /* Fatal error - ENOMEM, EIO... */
2434 blk_finish_plug(&plug
);
2435 if (!ret
&& !cycled
&& wbc
->nr_to_write
> 0) {
2437 mpd
.last_page
= writeback_index
- 1;
2443 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2445 * Set the writeback_index so that range_cyclic
2446 * mode will write it back later
2448 mapping
->writeback_index
= mpd
.first_page
;
2451 trace_ext4_writepages_result(inode
, wbc
, ret
,
2452 nr_to_write
- wbc
->nr_to_write
);
2456 static int ext4_nonda_switch(struct super_block
*sb
)
2458 s64 free_clusters
, dirty_clusters
;
2459 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2462 * switch to non delalloc mode if we are running low
2463 * on free block. The free block accounting via percpu
2464 * counters can get slightly wrong with percpu_counter_batch getting
2465 * accumulated on each CPU without updating global counters
2466 * Delalloc need an accurate free block accounting. So switch
2467 * to non delalloc when we are near to error range.
2470 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2472 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2474 * Start pushing delalloc when 1/2 of free blocks are dirty.
2476 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2477 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2479 if (2 * free_clusters
< 3 * dirty_clusters
||
2480 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2482 * free block count is less than 150% of dirty blocks
2483 * or free blocks is less than watermark
2490 /* We always reserve for an inode update; the superblock could be there too */
2491 static int ext4_da_write_credits(struct inode
*inode
, loff_t pos
, unsigned len
)
2493 if (likely(EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
2494 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
)))
2497 if (pos
+ len
<= 0x7fffffffULL
)
2500 /* We might need to update the superblock to set LARGE_FILE */
2504 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2505 loff_t pos
, unsigned len
, unsigned flags
,
2506 struct page
**pagep
, void **fsdata
)
2508 int ret
, retries
= 0;
2511 struct inode
*inode
= mapping
->host
;
2514 index
= pos
>> PAGE_CACHE_SHIFT
;
2516 if (ext4_nonda_switch(inode
->i_sb
)) {
2517 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2518 return ext4_write_begin(file
, mapping
, pos
,
2519 len
, flags
, pagep
, fsdata
);
2521 *fsdata
= (void *)0;
2522 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2524 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2525 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2535 * grab_cache_page_write_begin() can take a long time if the
2536 * system is thrashing due to memory pressure, or if the page
2537 * is being written back. So grab it first before we start
2538 * the transaction handle. This also allows us to allocate
2539 * the page (if needed) without using GFP_NOFS.
2542 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2548 * With delayed allocation, we don't log the i_disksize update
2549 * if there is delayed block allocation. But we still need
2550 * to journalling the i_disksize update if writes to the end
2551 * of file which has an already mapped buffer.
2554 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2555 ext4_da_write_credits(inode
, pos
, len
));
2556 if (IS_ERR(handle
)) {
2557 page_cache_release(page
);
2558 return PTR_ERR(handle
);
2562 if (page
->mapping
!= mapping
) {
2563 /* The page got truncated from under us */
2565 page_cache_release(page
);
2566 ext4_journal_stop(handle
);
2569 /* In case writeback began while the page was unlocked */
2570 wait_for_stable_page(page
);
2572 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2575 ext4_journal_stop(handle
);
2577 * block_write_begin may have instantiated a few blocks
2578 * outside i_size. Trim these off again. Don't need
2579 * i_size_read because we hold i_mutex.
2581 if (pos
+ len
> inode
->i_size
)
2582 ext4_truncate_failed_write(inode
);
2584 if (ret
== -ENOSPC
&&
2585 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2588 page_cache_release(page
);
2597 * Check if we should update i_disksize
2598 * when write to the end of file but not require block allocation
2600 static int ext4_da_should_update_i_disksize(struct page
*page
,
2601 unsigned long offset
)
2603 struct buffer_head
*bh
;
2604 struct inode
*inode
= page
->mapping
->host
;
2608 bh
= page_buffers(page
);
2609 idx
= offset
>> inode
->i_blkbits
;
2611 for (i
= 0; i
< idx
; i
++)
2612 bh
= bh
->b_this_page
;
2614 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2619 static int ext4_da_write_end(struct file
*file
,
2620 struct address_space
*mapping
,
2621 loff_t pos
, unsigned len
, unsigned copied
,
2622 struct page
*page
, void *fsdata
)
2624 struct inode
*inode
= mapping
->host
;
2626 handle_t
*handle
= ext4_journal_current_handle();
2628 unsigned long start
, end
;
2629 int write_mode
= (int)(unsigned long)fsdata
;
2631 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2632 return ext4_write_end(file
, mapping
, pos
,
2633 len
, copied
, page
, fsdata
);
2635 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2636 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2637 end
= start
+ copied
- 1;
2640 * generic_write_end() will run mark_inode_dirty() if i_size
2641 * changes. So let's piggyback the i_disksize mark_inode_dirty
2644 new_i_size
= pos
+ copied
;
2645 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2646 if (ext4_has_inline_data(inode
) ||
2647 ext4_da_should_update_i_disksize(page
, end
)) {
2648 ext4_update_i_disksize(inode
, new_i_size
);
2649 /* We need to mark inode dirty even if
2650 * new_i_size is less that inode->i_size
2651 * bu greater than i_disksize.(hint delalloc)
2653 ext4_mark_inode_dirty(handle
, inode
);
2657 if (write_mode
!= CONVERT_INLINE_DATA
&&
2658 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2659 ext4_has_inline_data(inode
))
2660 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2663 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2669 ret2
= ext4_journal_stop(handle
);
2673 return ret
? ret
: copied
;
2676 static void ext4_da_invalidatepage(struct page
*page
, unsigned int offset
,
2677 unsigned int length
)
2680 * Drop reserved blocks
2682 BUG_ON(!PageLocked(page
));
2683 if (!page_has_buffers(page
))
2686 ext4_da_page_release_reservation(page
, offset
, length
);
2689 ext4_invalidatepage(page
, offset
, length
);
2695 * Force all delayed allocation blocks to be allocated for a given inode.
2697 int ext4_alloc_da_blocks(struct inode
*inode
)
2699 trace_ext4_alloc_da_blocks(inode
);
2701 if (!EXT4_I(inode
)->i_reserved_data_blocks
)
2705 * We do something simple for now. The filemap_flush() will
2706 * also start triggering a write of the data blocks, which is
2707 * not strictly speaking necessary (and for users of
2708 * laptop_mode, not even desirable). However, to do otherwise
2709 * would require replicating code paths in:
2711 * ext4_writepages() ->
2712 * write_cache_pages() ---> (via passed in callback function)
2713 * __mpage_da_writepage() -->
2714 * mpage_add_bh_to_extent()
2715 * mpage_da_map_blocks()
2717 * The problem is that write_cache_pages(), located in
2718 * mm/page-writeback.c, marks pages clean in preparation for
2719 * doing I/O, which is not desirable if we're not planning on
2722 * We could call write_cache_pages(), and then redirty all of
2723 * the pages by calling redirty_page_for_writepage() but that
2724 * would be ugly in the extreme. So instead we would need to
2725 * replicate parts of the code in the above functions,
2726 * simplifying them because we wouldn't actually intend to
2727 * write out the pages, but rather only collect contiguous
2728 * logical block extents, call the multi-block allocator, and
2729 * then update the buffer heads with the block allocations.
2731 * For now, though, we'll cheat by calling filemap_flush(),
2732 * which will map the blocks, and start the I/O, but not
2733 * actually wait for the I/O to complete.
2735 return filemap_flush(inode
->i_mapping
);
2739 * bmap() is special. It gets used by applications such as lilo and by
2740 * the swapper to find the on-disk block of a specific piece of data.
2742 * Naturally, this is dangerous if the block concerned is still in the
2743 * journal. If somebody makes a swapfile on an ext4 data-journaling
2744 * filesystem and enables swap, then they may get a nasty shock when the
2745 * data getting swapped to that swapfile suddenly gets overwritten by
2746 * the original zero's written out previously to the journal and
2747 * awaiting writeback in the kernel's buffer cache.
2749 * So, if we see any bmap calls here on a modified, data-journaled file,
2750 * take extra steps to flush any blocks which might be in the cache.
2752 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2754 struct inode
*inode
= mapping
->host
;
2759 * We can get here for an inline file via the FIBMAP ioctl
2761 if (ext4_has_inline_data(inode
))
2764 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2765 test_opt(inode
->i_sb
, DELALLOC
)) {
2767 * With delalloc we want to sync the file
2768 * so that we can make sure we allocate
2771 filemap_write_and_wait(mapping
);
2774 if (EXT4_JOURNAL(inode
) &&
2775 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2777 * This is a REALLY heavyweight approach, but the use of
2778 * bmap on dirty files is expected to be extremely rare:
2779 * only if we run lilo or swapon on a freshly made file
2780 * do we expect this to happen.
2782 * (bmap requires CAP_SYS_RAWIO so this does not
2783 * represent an unprivileged user DOS attack --- we'd be
2784 * in trouble if mortal users could trigger this path at
2787 * NB. EXT4_STATE_JDATA is not set on files other than
2788 * regular files. If somebody wants to bmap a directory
2789 * or symlink and gets confused because the buffer
2790 * hasn't yet been flushed to disk, they deserve
2791 * everything they get.
2794 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2795 journal
= EXT4_JOURNAL(inode
);
2796 jbd2_journal_lock_updates(journal
);
2797 err
= jbd2_journal_flush(journal
);
2798 jbd2_journal_unlock_updates(journal
);
2804 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2807 static int ext4_readpage(struct file
*file
, struct page
*page
)
2810 struct inode
*inode
= page
->mapping
->host
;
2812 trace_ext4_readpage(page
);
2814 if (ext4_has_inline_data(inode
))
2815 ret
= ext4_readpage_inline(inode
, page
);
2818 return mpage_readpage(page
, ext4_get_block
);
2824 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2825 struct list_head
*pages
, unsigned nr_pages
)
2827 struct inode
*inode
= mapping
->host
;
2829 /* If the file has inline data, no need to do readpages. */
2830 if (ext4_has_inline_data(inode
))
2833 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
2836 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
2837 unsigned int length
)
2839 trace_ext4_invalidatepage(page
, offset
, length
);
2841 /* No journalling happens on data buffers when this function is used */
2842 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
2844 block_invalidatepage(page
, offset
, length
);
2847 static int __ext4_journalled_invalidatepage(struct page
*page
,
2848 unsigned int offset
,
2849 unsigned int length
)
2851 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2853 trace_ext4_journalled_invalidatepage(page
, offset
, length
);
2856 * If it's a full truncate we just forget about the pending dirtying
2858 if (offset
== 0 && length
== PAGE_CACHE_SIZE
)
2859 ClearPageChecked(page
);
2861 return jbd2_journal_invalidatepage(journal
, page
, offset
, length
);
2864 /* Wrapper for aops... */
2865 static void ext4_journalled_invalidatepage(struct page
*page
,
2866 unsigned int offset
,
2867 unsigned int length
)
2869 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
, length
) < 0);
2872 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
2874 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2876 trace_ext4_releasepage(page
);
2878 /* Page has dirty journalled data -> cannot release */
2879 if (PageChecked(page
))
2882 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
2884 return try_to_free_buffers(page
);
2888 * ext4_get_block used when preparing for a DIO write or buffer write.
2889 * We allocate an uinitialized extent if blocks haven't been allocated.
2890 * The extent will be converted to initialized after the IO is complete.
2892 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
2893 struct buffer_head
*bh_result
, int create
)
2895 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
2896 inode
->i_ino
, create
);
2897 return _ext4_get_block(inode
, iblock
, bh_result
,
2898 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
2901 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
2902 struct buffer_head
*bh_result
, int create
)
2904 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
2905 inode
->i_ino
, create
);
2906 return _ext4_get_block(inode
, iblock
, bh_result
,
2907 EXT4_GET_BLOCKS_NO_LOCK
);
2910 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
2911 ssize_t size
, void *private)
2913 ext4_io_end_t
*io_end
= iocb
->private;
2915 /* if not async direct IO just return */
2919 ext_debug("ext4_end_io_dio(): io_end 0x%p "
2920 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
2921 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
2924 iocb
->private = NULL
;
2925 io_end
->offset
= offset
;
2926 io_end
->size
= size
;
2927 ext4_put_io_end(io_end
);
2931 * For ext4 extent files, ext4 will do direct-io write to holes,
2932 * preallocated extents, and those write extend the file, no need to
2933 * fall back to buffered IO.
2935 * For holes, we fallocate those blocks, mark them as unwritten
2936 * If those blocks were preallocated, we mark sure they are split, but
2937 * still keep the range to write as unwritten.
2939 * The unwritten extents will be converted to written when DIO is completed.
2940 * For async direct IO, since the IO may still pending when return, we
2941 * set up an end_io call back function, which will do the conversion
2942 * when async direct IO completed.
2944 * If the O_DIRECT write will extend the file then add this inode to the
2945 * orphan list. So recovery will truncate it back to the original size
2946 * if the machine crashes during the write.
2949 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
2950 struct iov_iter
*iter
, loff_t offset
)
2952 struct file
*file
= iocb
->ki_filp
;
2953 struct inode
*inode
= file
->f_mapping
->host
;
2955 size_t count
= iov_iter_count(iter
);
2957 get_block_t
*get_block_func
= NULL
;
2959 loff_t final_size
= offset
+ count
;
2960 ext4_io_end_t
*io_end
= NULL
;
2962 /* Use the old path for reads and writes beyond i_size. */
2963 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
2964 return ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
2966 BUG_ON(iocb
->private == NULL
);
2969 * Make all waiters for direct IO properly wait also for extent
2970 * conversion. This also disallows race between truncate() and
2971 * overwrite DIO as i_dio_count needs to be incremented under i_mutex.
2974 atomic_inc(&inode
->i_dio_count
);
2976 /* If we do a overwrite dio, i_mutex locking can be released */
2977 overwrite
= *((int *)iocb
->private);
2980 down_read(&EXT4_I(inode
)->i_data_sem
);
2981 mutex_unlock(&inode
->i_mutex
);
2985 * We could direct write to holes and fallocate.
2987 * Allocated blocks to fill the hole are marked as
2988 * unwritten to prevent parallel buffered read to expose
2989 * the stale data before DIO complete the data IO.
2991 * As to previously fallocated extents, ext4 get_block will
2992 * just simply mark the buffer mapped but still keep the
2993 * extents unwritten.
2995 * For non AIO case, we will convert those unwritten extents
2996 * to written after return back from blockdev_direct_IO.
2998 * For async DIO, the conversion needs to be deferred when the
2999 * IO is completed. The ext4 end_io callback function will be
3000 * called to take care of the conversion work. Here for async
3001 * case, we allocate an io_end structure to hook to the iocb.
3003 iocb
->private = NULL
;
3004 ext4_inode_aio_set(inode
, NULL
);
3005 if (!is_sync_kiocb(iocb
)) {
3006 io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3012 * Grab reference for DIO. Will be dropped in ext4_end_io_dio()
3014 iocb
->private = ext4_get_io_end(io_end
);
3016 * we save the io structure for current async direct
3017 * IO, so that later ext4_map_blocks() could flag the
3018 * io structure whether there is a unwritten extents
3019 * needs to be converted when IO is completed.
3021 ext4_inode_aio_set(inode
, io_end
);
3025 get_block_func
= ext4_get_block_write_nolock
;
3027 get_block_func
= ext4_get_block_write
;
3028 dio_flags
= DIO_LOCKING
;
3031 ret
= dax_do_io(rw
, iocb
, inode
, iter
, offset
, get_block_func
,
3032 ext4_end_io_dio
, dio_flags
);
3034 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3035 inode
->i_sb
->s_bdev
, iter
, offset
,
3037 ext4_end_io_dio
, NULL
, dio_flags
);
3040 * Put our reference to io_end. This can free the io_end structure e.g.
3041 * in sync IO case or in case of error. It can even perform extent
3042 * conversion if all bios we submitted finished before we got here.
3043 * Note that in that case iocb->private can be already set to NULL
3047 ext4_inode_aio_set(inode
, NULL
);
3048 ext4_put_io_end(io_end
);
3050 * When no IO was submitted ext4_end_io_dio() was not
3051 * called so we have to put iocb's reference.
3053 if (ret
<= 0 && ret
!= -EIOCBQUEUED
&& iocb
->private) {
3054 WARN_ON(iocb
->private != io_end
);
3055 WARN_ON(io_end
->flag
& EXT4_IO_END_UNWRITTEN
);
3056 ext4_put_io_end(io_end
);
3057 iocb
->private = NULL
;
3060 if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3061 EXT4_STATE_DIO_UNWRITTEN
)) {
3064 * for non AIO case, since the IO is already
3065 * completed, we could do the conversion right here
3067 err
= ext4_convert_unwritten_extents(NULL
, inode
,
3071 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3076 inode_dio_done(inode
);
3077 /* take i_mutex locking again if we do a ovewrite dio */
3079 up_read(&EXT4_I(inode
)->i_data_sem
);
3080 mutex_lock(&inode
->i_mutex
);
3086 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3087 struct iov_iter
*iter
, loff_t offset
)
3089 struct file
*file
= iocb
->ki_filp
;
3090 struct inode
*inode
= file
->f_mapping
->host
;
3091 size_t count
= iov_iter_count(iter
);
3095 * If we are doing data journalling we don't support O_DIRECT
3097 if (ext4_should_journal_data(inode
))
3100 /* Let buffer I/O handle the inline data case. */
3101 if (ext4_has_inline_data(inode
))
3104 trace_ext4_direct_IO_enter(inode
, offset
, count
, rw
);
3105 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3106 ret
= ext4_ext_direct_IO(rw
, iocb
, iter
, offset
);
3108 ret
= ext4_ind_direct_IO(rw
, iocb
, iter
, offset
);
3109 trace_ext4_direct_IO_exit(inode
, offset
, count
, rw
, ret
);
3114 * Pages can be marked dirty completely asynchronously from ext4's journalling
3115 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3116 * much here because ->set_page_dirty is called under VFS locks. The page is
3117 * not necessarily locked.
3119 * We cannot just dirty the page and leave attached buffers clean, because the
3120 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3121 * or jbddirty because all the journalling code will explode.
3123 * So what we do is to mark the page "pending dirty" and next time writepage
3124 * is called, propagate that into the buffers appropriately.
3126 static int ext4_journalled_set_page_dirty(struct page
*page
)
3128 SetPageChecked(page
);
3129 return __set_page_dirty_nobuffers(page
);
3132 static const struct address_space_operations ext4_aops
= {
3133 .readpage
= ext4_readpage
,
3134 .readpages
= ext4_readpages
,
3135 .writepage
= ext4_writepage
,
3136 .writepages
= ext4_writepages
,
3137 .write_begin
= ext4_write_begin
,
3138 .write_end
= ext4_write_end
,
3140 .invalidatepage
= ext4_invalidatepage
,
3141 .releasepage
= ext4_releasepage
,
3142 .direct_IO
= ext4_direct_IO
,
3143 .migratepage
= buffer_migrate_page
,
3144 .is_partially_uptodate
= block_is_partially_uptodate
,
3145 .error_remove_page
= generic_error_remove_page
,
3148 static const struct address_space_operations ext4_journalled_aops
= {
3149 .readpage
= ext4_readpage
,
3150 .readpages
= ext4_readpages
,
3151 .writepage
= ext4_writepage
,
3152 .writepages
= ext4_writepages
,
3153 .write_begin
= ext4_write_begin
,
3154 .write_end
= ext4_journalled_write_end
,
3155 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3157 .invalidatepage
= ext4_journalled_invalidatepage
,
3158 .releasepage
= ext4_releasepage
,
3159 .direct_IO
= ext4_direct_IO
,
3160 .is_partially_uptodate
= block_is_partially_uptodate
,
3161 .error_remove_page
= generic_error_remove_page
,
3164 static const struct address_space_operations ext4_da_aops
= {
3165 .readpage
= ext4_readpage
,
3166 .readpages
= ext4_readpages
,
3167 .writepage
= ext4_writepage
,
3168 .writepages
= ext4_writepages
,
3169 .write_begin
= ext4_da_write_begin
,
3170 .write_end
= ext4_da_write_end
,
3172 .invalidatepage
= ext4_da_invalidatepage
,
3173 .releasepage
= ext4_releasepage
,
3174 .direct_IO
= ext4_direct_IO
,
3175 .migratepage
= buffer_migrate_page
,
3176 .is_partially_uptodate
= block_is_partially_uptodate
,
3177 .error_remove_page
= generic_error_remove_page
,
3180 void ext4_set_aops(struct inode
*inode
)
3182 switch (ext4_inode_journal_mode(inode
)) {
3183 case EXT4_INODE_ORDERED_DATA_MODE
:
3184 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3186 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3187 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3189 case EXT4_INODE_JOURNAL_DATA_MODE
:
3190 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3195 if (test_opt(inode
->i_sb
, DELALLOC
))
3196 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3198 inode
->i_mapping
->a_ops
= &ext4_aops
;
3201 static int __ext4_block_zero_page_range(handle_t
*handle
,
3202 struct address_space
*mapping
, loff_t from
, loff_t length
)
3204 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3205 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3206 unsigned blocksize
, pos
;
3208 struct inode
*inode
= mapping
->host
;
3209 struct buffer_head
*bh
;
3213 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3214 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3218 blocksize
= inode
->i_sb
->s_blocksize
;
3220 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3222 if (!page_has_buffers(page
))
3223 create_empty_buffers(page
, blocksize
, 0);
3225 /* Find the buffer that contains "offset" */
3226 bh
= page_buffers(page
);
3228 while (offset
>= pos
) {
3229 bh
= bh
->b_this_page
;
3233 if (buffer_freed(bh
)) {
3234 BUFFER_TRACE(bh
, "freed: skip");
3237 if (!buffer_mapped(bh
)) {
3238 BUFFER_TRACE(bh
, "unmapped");
3239 ext4_get_block(inode
, iblock
, bh
, 0);
3240 /* unmapped? It's a hole - nothing to do */
3241 if (!buffer_mapped(bh
)) {
3242 BUFFER_TRACE(bh
, "still unmapped");
3247 /* Ok, it's mapped. Make sure it's up-to-date */
3248 if (PageUptodate(page
))
3249 set_buffer_uptodate(bh
);
3251 if (!buffer_uptodate(bh
)) {
3253 ll_rw_block(READ
, 1, &bh
);
3255 /* Uhhuh. Read error. Complain and punt. */
3256 if (!buffer_uptodate(bh
))
3259 if (ext4_should_journal_data(inode
)) {
3260 BUFFER_TRACE(bh
, "get write access");
3261 err
= ext4_journal_get_write_access(handle
, bh
);
3265 zero_user(page
, offset
, length
);
3266 BUFFER_TRACE(bh
, "zeroed end of block");
3268 if (ext4_should_journal_data(inode
)) {
3269 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3272 mark_buffer_dirty(bh
);
3273 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
))
3274 err
= ext4_jbd2_file_inode(handle
, inode
);
3279 page_cache_release(page
);
3284 * ext4_block_zero_page_range() zeros out a mapping of length 'length'
3285 * starting from file offset 'from'. The range to be zero'd must
3286 * be contained with in one block. If the specified range exceeds
3287 * the end of the block it will be shortened to end of the block
3288 * that cooresponds to 'from'
3290 static int ext4_block_zero_page_range(handle_t
*handle
,
3291 struct address_space
*mapping
, loff_t from
, loff_t length
)
3293 struct inode
*inode
= mapping
->host
;
3294 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3295 unsigned blocksize
= inode
->i_sb
->s_blocksize
;
3296 unsigned max
= blocksize
- (offset
& (blocksize
- 1));
3299 * correct length if it does not fall between
3300 * 'from' and the end of the block
3302 if (length
> max
|| length
< 0)
3306 return dax_zero_page_range(inode
, from
, length
, ext4_get_block
);
3307 return __ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3311 * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
3312 * up to the end of the block which corresponds to `from'.
3313 * This required during truncate. We need to physically zero the tail end
3314 * of that block so it doesn't yield old data if the file is later grown.
3316 static int ext4_block_truncate_page(handle_t
*handle
,
3317 struct address_space
*mapping
, loff_t from
)
3319 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3322 struct inode
*inode
= mapping
->host
;
3324 blocksize
= inode
->i_sb
->s_blocksize
;
3325 length
= blocksize
- (offset
& (blocksize
- 1));
3327 return ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3330 int ext4_zero_partial_blocks(handle_t
*handle
, struct inode
*inode
,
3331 loff_t lstart
, loff_t length
)
3333 struct super_block
*sb
= inode
->i_sb
;
3334 struct address_space
*mapping
= inode
->i_mapping
;
3335 unsigned partial_start
, partial_end
;
3336 ext4_fsblk_t start
, end
;
3337 loff_t byte_end
= (lstart
+ length
- 1);
3340 partial_start
= lstart
& (sb
->s_blocksize
- 1);
3341 partial_end
= byte_end
& (sb
->s_blocksize
- 1);
3343 start
= lstart
>> sb
->s_blocksize_bits
;
3344 end
= byte_end
>> sb
->s_blocksize_bits
;
3346 /* Handle partial zero within the single block */
3348 (partial_start
|| (partial_end
!= sb
->s_blocksize
- 1))) {
3349 err
= ext4_block_zero_page_range(handle
, mapping
,
3353 /* Handle partial zero out on the start of the range */
3354 if (partial_start
) {
3355 err
= ext4_block_zero_page_range(handle
, mapping
,
3356 lstart
, sb
->s_blocksize
);
3360 /* Handle partial zero out on the end of the range */
3361 if (partial_end
!= sb
->s_blocksize
- 1)
3362 err
= ext4_block_zero_page_range(handle
, mapping
,
3363 byte_end
- partial_end
,
3368 int ext4_can_truncate(struct inode
*inode
)
3370 if (S_ISREG(inode
->i_mode
))
3372 if (S_ISDIR(inode
->i_mode
))
3374 if (S_ISLNK(inode
->i_mode
))
3375 return !ext4_inode_is_fast_symlink(inode
);
3380 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3381 * associated with the given offset and length
3383 * @inode: File inode
3384 * @offset: The offset where the hole will begin
3385 * @len: The length of the hole
3387 * Returns: 0 on success or negative on failure
3390 int ext4_punch_hole(struct inode
*inode
, loff_t offset
, loff_t length
)
3392 struct super_block
*sb
= inode
->i_sb
;
3393 ext4_lblk_t first_block
, stop_block
;
3394 struct address_space
*mapping
= inode
->i_mapping
;
3395 loff_t first_block_offset
, last_block_offset
;
3397 unsigned int credits
;
3400 if (!S_ISREG(inode
->i_mode
))
3403 trace_ext4_punch_hole(inode
, offset
, length
, 0);
3406 * Write out all dirty pages to avoid race conditions
3407 * Then release them.
3409 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3410 ret
= filemap_write_and_wait_range(mapping
, offset
,
3411 offset
+ length
- 1);
3416 mutex_lock(&inode
->i_mutex
);
3418 /* No need to punch hole beyond i_size */
3419 if (offset
>= inode
->i_size
)
3423 * If the hole extends beyond i_size, set the hole
3424 * to end after the page that contains i_size
3426 if (offset
+ length
> inode
->i_size
) {
3427 length
= inode
->i_size
+
3428 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3432 if (offset
& (sb
->s_blocksize
- 1) ||
3433 (offset
+ length
) & (sb
->s_blocksize
- 1)) {
3435 * Attach jinode to inode for jbd2 if we do any zeroing of
3438 ret
= ext4_inode_attach_jinode(inode
);
3444 first_block_offset
= round_up(offset
, sb
->s_blocksize
);
3445 last_block_offset
= round_down((offset
+ length
), sb
->s_blocksize
) - 1;
3447 /* Now release the pages and zero block aligned part of pages*/
3448 if (last_block_offset
> first_block_offset
)
3449 truncate_pagecache_range(inode
, first_block_offset
,
3452 /* Wait all existing dio workers, newcomers will block on i_mutex */
3453 ext4_inode_block_unlocked_dio(inode
);
3454 inode_dio_wait(inode
);
3456 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3457 credits
= ext4_writepage_trans_blocks(inode
);
3459 credits
= ext4_blocks_for_truncate(inode
);
3460 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3461 if (IS_ERR(handle
)) {
3462 ret
= PTR_ERR(handle
);
3463 ext4_std_error(sb
, ret
);
3467 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
,
3472 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3473 EXT4_BLOCK_SIZE_BITS(sb
);
3474 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3476 /* If there are no blocks to remove, return now */
3477 if (first_block
>= stop_block
)
3480 down_write(&EXT4_I(inode
)->i_data_sem
);
3481 ext4_discard_preallocations(inode
);
3483 ret
= ext4_es_remove_extent(inode
, first_block
,
3484 stop_block
- first_block
);
3486 up_write(&EXT4_I(inode
)->i_data_sem
);
3490 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3491 ret
= ext4_ext_remove_space(inode
, first_block
,
3494 ret
= ext4_ind_remove_space(handle
, inode
, first_block
,
3497 up_write(&EXT4_I(inode
)->i_data_sem
);
3499 ext4_handle_sync(handle
);
3501 /* Now release the pages again to reduce race window */
3502 if (last_block_offset
> first_block_offset
)
3503 truncate_pagecache_range(inode
, first_block_offset
,
3506 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3507 ext4_mark_inode_dirty(handle
, inode
);
3509 ext4_journal_stop(handle
);
3511 ext4_inode_resume_unlocked_dio(inode
);
3513 mutex_unlock(&inode
->i_mutex
);
3517 int ext4_inode_attach_jinode(struct inode
*inode
)
3519 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3520 struct jbd2_inode
*jinode
;
3522 if (ei
->jinode
|| !EXT4_SB(inode
->i_sb
)->s_journal
)
3525 jinode
= jbd2_alloc_inode(GFP_KERNEL
);
3526 spin_lock(&inode
->i_lock
);
3529 spin_unlock(&inode
->i_lock
);
3532 ei
->jinode
= jinode
;
3533 jbd2_journal_init_jbd_inode(ei
->jinode
, inode
);
3536 spin_unlock(&inode
->i_lock
);
3537 if (unlikely(jinode
!= NULL
))
3538 jbd2_free_inode(jinode
);
3545 * We block out ext4_get_block() block instantiations across the entire
3546 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3547 * simultaneously on behalf of the same inode.
3549 * As we work through the truncate and commit bits of it to the journal there
3550 * is one core, guiding principle: the file's tree must always be consistent on
3551 * disk. We must be able to restart the truncate after a crash.
3553 * The file's tree may be transiently inconsistent in memory (although it
3554 * probably isn't), but whenever we close off and commit a journal transaction,
3555 * the contents of (the filesystem + the journal) must be consistent and
3556 * restartable. It's pretty simple, really: bottom up, right to left (although
3557 * left-to-right works OK too).
3559 * Note that at recovery time, journal replay occurs *before* the restart of
3560 * truncate against the orphan inode list.
3562 * The committed inode has the new, desired i_size (which is the same as
3563 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3564 * that this inode's truncate did not complete and it will again call
3565 * ext4_truncate() to have another go. So there will be instantiated blocks
3566 * to the right of the truncation point in a crashed ext4 filesystem. But
3567 * that's fine - as long as they are linked from the inode, the post-crash
3568 * ext4_truncate() run will find them and release them.
3570 void ext4_truncate(struct inode
*inode
)
3572 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3573 unsigned int credits
;
3575 struct address_space
*mapping
= inode
->i_mapping
;
3578 * There is a possibility that we're either freeing the inode
3579 * or it's a completely new inode. In those cases we might not
3580 * have i_mutex locked because it's not necessary.
3582 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3583 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3584 trace_ext4_truncate_enter(inode
);
3586 if (!ext4_can_truncate(inode
))
3589 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3591 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3592 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3594 if (ext4_has_inline_data(inode
)) {
3597 ext4_inline_data_truncate(inode
, &has_inline
);
3602 /* If we zero-out tail of the page, we have to create jinode for jbd2 */
3603 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1)) {
3604 if (ext4_inode_attach_jinode(inode
) < 0)
3608 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3609 credits
= ext4_writepage_trans_blocks(inode
);
3611 credits
= ext4_blocks_for_truncate(inode
);
3613 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3614 if (IS_ERR(handle
)) {
3615 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3619 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1))
3620 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3623 * We add the inode to the orphan list, so that if this
3624 * truncate spans multiple transactions, and we crash, we will
3625 * resume the truncate when the filesystem recovers. It also
3626 * marks the inode dirty, to catch the new size.
3628 * Implication: the file must always be in a sane, consistent
3629 * truncatable state while each transaction commits.
3631 if (ext4_orphan_add(handle
, inode
))
3634 down_write(&EXT4_I(inode
)->i_data_sem
);
3636 ext4_discard_preallocations(inode
);
3638 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3639 ext4_ext_truncate(handle
, inode
);
3641 ext4_ind_truncate(handle
, inode
);
3643 up_write(&ei
->i_data_sem
);
3646 ext4_handle_sync(handle
);
3650 * If this was a simple ftruncate() and the file will remain alive,
3651 * then we need to clear up the orphan record which we created above.
3652 * However, if this was a real unlink then we were called by
3653 * ext4_evict_inode(), and we allow that function to clean up the
3654 * orphan info for us.
3657 ext4_orphan_del(handle
, inode
);
3659 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3660 ext4_mark_inode_dirty(handle
, inode
);
3661 ext4_journal_stop(handle
);
3663 trace_ext4_truncate_exit(inode
);
3667 * ext4_get_inode_loc returns with an extra refcount against the inode's
3668 * underlying buffer_head on success. If 'in_mem' is true, we have all
3669 * data in memory that is needed to recreate the on-disk version of this
3672 static int __ext4_get_inode_loc(struct inode
*inode
,
3673 struct ext4_iloc
*iloc
, int in_mem
)
3675 struct ext4_group_desc
*gdp
;
3676 struct buffer_head
*bh
;
3677 struct super_block
*sb
= inode
->i_sb
;
3679 int inodes_per_block
, inode_offset
;
3682 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3685 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3686 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3691 * Figure out the offset within the block group inode table
3693 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3694 inode_offset
= ((inode
->i_ino
- 1) %
3695 EXT4_INODES_PER_GROUP(sb
));
3696 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3697 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3699 bh
= sb_getblk(sb
, block
);
3702 if (!buffer_uptodate(bh
)) {
3706 * If the buffer has the write error flag, we have failed
3707 * to write out another inode in the same block. In this
3708 * case, we don't have to read the block because we may
3709 * read the old inode data successfully.
3711 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3712 set_buffer_uptodate(bh
);
3714 if (buffer_uptodate(bh
)) {
3715 /* someone brought it uptodate while we waited */
3721 * If we have all information of the inode in memory and this
3722 * is the only valid inode in the block, we need not read the
3726 struct buffer_head
*bitmap_bh
;
3729 start
= inode_offset
& ~(inodes_per_block
- 1);
3731 /* Is the inode bitmap in cache? */
3732 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3733 if (unlikely(!bitmap_bh
))
3737 * If the inode bitmap isn't in cache then the
3738 * optimisation may end up performing two reads instead
3739 * of one, so skip it.
3741 if (!buffer_uptodate(bitmap_bh
)) {
3745 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
3746 if (i
== inode_offset
)
3748 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
3752 if (i
== start
+ inodes_per_block
) {
3753 /* all other inodes are free, so skip I/O */
3754 memset(bh
->b_data
, 0, bh
->b_size
);
3755 set_buffer_uptodate(bh
);
3763 * If we need to do any I/O, try to pre-readahead extra
3764 * blocks from the inode table.
3766 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
3767 ext4_fsblk_t b
, end
, table
;
3769 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
3771 table
= ext4_inode_table(sb
, gdp
);
3772 /* s_inode_readahead_blks is always a power of 2 */
3773 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
3777 num
= EXT4_INODES_PER_GROUP(sb
);
3778 if (ext4_has_group_desc_csum(sb
))
3779 num
-= ext4_itable_unused_count(sb
, gdp
);
3780 table
+= num
/ inodes_per_block
;
3784 sb_breadahead(sb
, b
++);
3788 * There are other valid inodes in the buffer, this inode
3789 * has in-inode xattrs, or we don't have this inode in memory.
3790 * Read the block from disk.
3792 trace_ext4_load_inode(inode
);
3794 bh
->b_end_io
= end_buffer_read_sync
;
3795 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
3797 if (!buffer_uptodate(bh
)) {
3798 EXT4_ERROR_INODE_BLOCK(inode
, block
,
3799 "unable to read itable block");
3809 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
3811 /* We have all inode data except xattrs in memory here. */
3812 return __ext4_get_inode_loc(inode
, iloc
,
3813 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
3816 void ext4_set_inode_flags(struct inode
*inode
)
3818 unsigned int flags
= EXT4_I(inode
)->i_flags
;
3819 unsigned int new_fl
= 0;
3821 if (flags
& EXT4_SYNC_FL
)
3823 if (flags
& EXT4_APPEND_FL
)
3825 if (flags
& EXT4_IMMUTABLE_FL
)
3826 new_fl
|= S_IMMUTABLE
;
3827 if (flags
& EXT4_NOATIME_FL
)
3828 new_fl
|= S_NOATIME
;
3829 if (flags
& EXT4_DIRSYNC_FL
)
3830 new_fl
|= S_DIRSYNC
;
3831 if (test_opt(inode
->i_sb
, DAX
))
3833 inode_set_flags(inode
, new_fl
,
3834 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
|S_DAX
);
3837 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
3838 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
3840 unsigned int vfs_fl
;
3841 unsigned long old_fl
, new_fl
;
3844 vfs_fl
= ei
->vfs_inode
.i_flags
;
3845 old_fl
= ei
->i_flags
;
3846 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
3847 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
3849 if (vfs_fl
& S_SYNC
)
3850 new_fl
|= EXT4_SYNC_FL
;
3851 if (vfs_fl
& S_APPEND
)
3852 new_fl
|= EXT4_APPEND_FL
;
3853 if (vfs_fl
& S_IMMUTABLE
)
3854 new_fl
|= EXT4_IMMUTABLE_FL
;
3855 if (vfs_fl
& S_NOATIME
)
3856 new_fl
|= EXT4_NOATIME_FL
;
3857 if (vfs_fl
& S_DIRSYNC
)
3858 new_fl
|= EXT4_DIRSYNC_FL
;
3859 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
3862 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
3863 struct ext4_inode_info
*ei
)
3866 struct inode
*inode
= &(ei
->vfs_inode
);
3867 struct super_block
*sb
= inode
->i_sb
;
3869 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
3870 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
3871 /* we are using combined 48 bit field */
3872 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
3873 le32_to_cpu(raw_inode
->i_blocks_lo
);
3874 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
3875 /* i_blocks represent file system block size */
3876 return i_blocks
<< (inode
->i_blkbits
- 9);
3881 return le32_to_cpu(raw_inode
->i_blocks_lo
);
3885 static inline void ext4_iget_extra_inode(struct inode
*inode
,
3886 struct ext4_inode
*raw_inode
,
3887 struct ext4_inode_info
*ei
)
3889 __le32
*magic
= (void *)raw_inode
+
3890 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
3891 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
3892 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
3893 ext4_find_inline_data_nolock(inode
);
3895 EXT4_I(inode
)->i_inline_off
= 0;
3898 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
3900 struct ext4_iloc iloc
;
3901 struct ext4_inode
*raw_inode
;
3902 struct ext4_inode_info
*ei
;
3903 struct inode
*inode
;
3904 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
3910 inode
= iget_locked(sb
, ino
);
3912 return ERR_PTR(-ENOMEM
);
3913 if (!(inode
->i_state
& I_NEW
))
3919 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
3922 raw_inode
= ext4_raw_inode(&iloc
);
3924 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
3925 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
3926 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
3927 EXT4_INODE_SIZE(inode
->i_sb
)) {
3928 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
3929 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
3930 EXT4_INODE_SIZE(inode
->i_sb
));
3935 ei
->i_extra_isize
= 0;
3937 /* Precompute checksum seed for inode metadata */
3938 if (ext4_has_metadata_csum(sb
)) {
3939 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
3941 __le32 inum
= cpu_to_le32(inode
->i_ino
);
3942 __le32 gen
= raw_inode
->i_generation
;
3943 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
3945 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
3949 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
3950 EXT4_ERROR_INODE(inode
, "checksum invalid");
3955 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
3956 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
3957 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
3958 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
3959 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
3960 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
3962 i_uid_write(inode
, i_uid
);
3963 i_gid_write(inode
, i_gid
);
3964 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
3966 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
3967 ei
->i_inline_off
= 0;
3968 ei
->i_dir_start_lookup
= 0;
3969 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
3970 /* We now have enough fields to check if the inode was active or not.
3971 * This is needed because nfsd might try to access dead inodes
3972 * the test is that same one that e2fsck uses
3973 * NeilBrown 1999oct15
3975 if (inode
->i_nlink
== 0) {
3976 if ((inode
->i_mode
== 0 ||
3977 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
3978 ino
!= EXT4_BOOT_LOADER_INO
) {
3979 /* this inode is deleted */
3983 /* The only unlinked inodes we let through here have
3984 * valid i_mode and are being read by the orphan
3985 * recovery code: that's fine, we're about to complete
3986 * the process of deleting those.
3987 * OR it is the EXT4_BOOT_LOADER_INO which is
3988 * not initialized on a new filesystem. */
3990 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
3991 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
3992 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
3993 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
3995 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
3996 inode
->i_size
= ext4_isize(raw_inode
);
3997 ei
->i_disksize
= inode
->i_size
;
3999 ei
->i_reserved_quota
= 0;
4001 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4002 ei
->i_block_group
= iloc
.block_group
;
4003 ei
->i_last_alloc_group
= ~0;
4005 * NOTE! The in-memory inode i_data array is in little-endian order
4006 * even on big-endian machines: we do NOT byteswap the block numbers!
4008 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4009 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4010 INIT_LIST_HEAD(&ei
->i_orphan
);
4013 * Set transaction id's of transactions that have to be committed
4014 * to finish f[data]sync. We set them to currently running transaction
4015 * as we cannot be sure that the inode or some of its metadata isn't
4016 * part of the transaction - the inode could have been reclaimed and
4017 * now it is reread from disk.
4020 transaction_t
*transaction
;
4023 read_lock(&journal
->j_state_lock
);
4024 if (journal
->j_running_transaction
)
4025 transaction
= journal
->j_running_transaction
;
4027 transaction
= journal
->j_committing_transaction
;
4029 tid
= transaction
->t_tid
;
4031 tid
= journal
->j_commit_sequence
;
4032 read_unlock(&journal
->j_state_lock
);
4033 ei
->i_sync_tid
= tid
;
4034 ei
->i_datasync_tid
= tid
;
4037 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4038 if (ei
->i_extra_isize
== 0) {
4039 /* The extra space is currently unused. Use it. */
4040 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4041 EXT4_GOOD_OLD_INODE_SIZE
;
4043 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4047 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4048 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4049 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4050 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4052 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4053 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4054 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4055 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4057 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4062 if (ei
->i_file_acl
&&
4063 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4064 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4068 } else if (!ext4_has_inline_data(inode
)) {
4069 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4070 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4071 (S_ISLNK(inode
->i_mode
) &&
4072 !ext4_inode_is_fast_symlink(inode
))))
4073 /* Validate extent which is part of inode */
4074 ret
= ext4_ext_check_inode(inode
);
4075 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4076 (S_ISLNK(inode
->i_mode
) &&
4077 !ext4_inode_is_fast_symlink(inode
))) {
4078 /* Validate block references which are part of inode */
4079 ret
= ext4_ind_check_inode(inode
);
4085 if (S_ISREG(inode
->i_mode
)) {
4086 inode
->i_op
= &ext4_file_inode_operations
;
4087 if (test_opt(inode
->i_sb
, DAX
))
4088 inode
->i_fop
= &ext4_dax_file_operations
;
4090 inode
->i_fop
= &ext4_file_operations
;
4091 ext4_set_aops(inode
);
4092 } else if (S_ISDIR(inode
->i_mode
)) {
4093 inode
->i_op
= &ext4_dir_inode_operations
;
4094 inode
->i_fop
= &ext4_dir_operations
;
4095 } else if (S_ISLNK(inode
->i_mode
)) {
4096 if (ext4_inode_is_fast_symlink(inode
)) {
4097 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4098 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4099 sizeof(ei
->i_data
) - 1);
4101 inode
->i_op
= &ext4_symlink_inode_operations
;
4102 ext4_set_aops(inode
);
4104 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4105 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4106 inode
->i_op
= &ext4_special_inode_operations
;
4107 if (raw_inode
->i_block
[0])
4108 init_special_inode(inode
, inode
->i_mode
,
4109 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4111 init_special_inode(inode
, inode
->i_mode
,
4112 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4113 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4114 make_bad_inode(inode
);
4117 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4121 ext4_set_inode_flags(inode
);
4122 unlock_new_inode(inode
);
4128 return ERR_PTR(ret
);
4131 struct inode
*ext4_iget_normal(struct super_block
*sb
, unsigned long ino
)
4133 if (ino
< EXT4_FIRST_INO(sb
) && ino
!= EXT4_ROOT_INO
)
4134 return ERR_PTR(-EIO
);
4135 return ext4_iget(sb
, ino
);
4138 static int ext4_inode_blocks_set(handle_t
*handle
,
4139 struct ext4_inode
*raw_inode
,
4140 struct ext4_inode_info
*ei
)
4142 struct inode
*inode
= &(ei
->vfs_inode
);
4143 u64 i_blocks
= inode
->i_blocks
;
4144 struct super_block
*sb
= inode
->i_sb
;
4146 if (i_blocks
<= ~0U) {
4148 * i_blocks can be represented in a 32 bit variable
4149 * as multiple of 512 bytes
4151 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4152 raw_inode
->i_blocks_high
= 0;
4153 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4156 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4159 if (i_blocks
<= 0xffffffffffffULL
) {
4161 * i_blocks can be represented in a 48 bit variable
4162 * as multiple of 512 bytes
4164 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4165 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4166 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4168 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4169 /* i_block is stored in file system block size */
4170 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4171 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4172 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4177 struct other_inode
{
4178 unsigned long orig_ino
;
4179 struct ext4_inode
*raw_inode
;
4182 static int other_inode_match(struct inode
* inode
, unsigned long ino
,
4185 struct other_inode
*oi
= (struct other_inode
*) data
;
4187 if ((inode
->i_ino
!= ino
) ||
4188 (inode
->i_state
& (I_FREEING
| I_WILL_FREE
| I_NEW
|
4189 I_DIRTY_SYNC
| I_DIRTY_DATASYNC
)) ||
4190 ((inode
->i_state
& I_DIRTY_TIME
) == 0))
4192 spin_lock(&inode
->i_lock
);
4193 if (((inode
->i_state
& (I_FREEING
| I_WILL_FREE
| I_NEW
|
4194 I_DIRTY_SYNC
| I_DIRTY_DATASYNC
)) == 0) &&
4195 (inode
->i_state
& I_DIRTY_TIME
)) {
4196 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4198 inode
->i_state
&= ~(I_DIRTY_TIME
| I_DIRTY_TIME_EXPIRED
);
4199 spin_unlock(&inode
->i_lock
);
4201 spin_lock(&ei
->i_raw_lock
);
4202 EXT4_INODE_SET_XTIME(i_ctime
, inode
, oi
->raw_inode
);
4203 EXT4_INODE_SET_XTIME(i_mtime
, inode
, oi
->raw_inode
);
4204 EXT4_INODE_SET_XTIME(i_atime
, inode
, oi
->raw_inode
);
4205 ext4_inode_csum_set(inode
, oi
->raw_inode
, ei
);
4206 spin_unlock(&ei
->i_raw_lock
);
4207 trace_ext4_other_inode_update_time(inode
, oi
->orig_ino
);
4210 spin_unlock(&inode
->i_lock
);
4215 * Opportunistically update the other time fields for other inodes in
4216 * the same inode table block.
4218 static void ext4_update_other_inodes_time(struct super_block
*sb
,
4219 unsigned long orig_ino
, char *buf
)
4221 struct other_inode oi
;
4223 int i
, inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
4224 int inode_size
= EXT4_INODE_SIZE(sb
);
4226 oi
.orig_ino
= orig_ino
;
4227 ino
= orig_ino
& ~(inodes_per_block
- 1);
4228 for (i
= 0; i
< inodes_per_block
; i
++, ino
++, buf
+= inode_size
) {
4229 if (ino
== orig_ino
)
4231 oi
.raw_inode
= (struct ext4_inode
*) buf
;
4232 (void) find_inode_nowait(sb
, ino
, other_inode_match
, &oi
);
4237 * Post the struct inode info into an on-disk inode location in the
4238 * buffer-cache. This gobbles the caller's reference to the
4239 * buffer_head in the inode location struct.
4241 * The caller must have write access to iloc->bh.
4243 static int ext4_do_update_inode(handle_t
*handle
,
4244 struct inode
*inode
,
4245 struct ext4_iloc
*iloc
)
4247 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4248 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4249 struct buffer_head
*bh
= iloc
->bh
;
4250 struct super_block
*sb
= inode
->i_sb
;
4251 int err
= 0, rc
, block
;
4252 int need_datasync
= 0, set_large_file
= 0;
4256 spin_lock(&ei
->i_raw_lock
);
4258 /* For fields not tracked in the in-memory inode,
4259 * initialise them to zero for new inodes. */
4260 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4261 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4263 ext4_get_inode_flags(ei
);
4264 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4265 i_uid
= i_uid_read(inode
);
4266 i_gid
= i_gid_read(inode
);
4267 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4268 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4269 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4271 * Fix up interoperability with old kernels. Otherwise, old inodes get
4272 * re-used with the upper 16 bits of the uid/gid intact
4275 raw_inode
->i_uid_high
=
4276 cpu_to_le16(high_16_bits(i_uid
));
4277 raw_inode
->i_gid_high
=
4278 cpu_to_le16(high_16_bits(i_gid
));
4280 raw_inode
->i_uid_high
= 0;
4281 raw_inode
->i_gid_high
= 0;
4284 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4285 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4286 raw_inode
->i_uid_high
= 0;
4287 raw_inode
->i_gid_high
= 0;
4289 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4291 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4292 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4293 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4294 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4296 err
= ext4_inode_blocks_set(handle
, raw_inode
, ei
);
4298 spin_unlock(&ei
->i_raw_lock
);
4301 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4302 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4303 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
)))
4304 raw_inode
->i_file_acl_high
=
4305 cpu_to_le16(ei
->i_file_acl
>> 32);
4306 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4307 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4308 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4311 if (ei
->i_disksize
> 0x7fffffffULL
) {
4312 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4313 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4314 EXT4_SB(sb
)->s_es
->s_rev_level
==
4315 cpu_to_le32(EXT4_GOOD_OLD_REV
))
4318 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4319 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4320 if (old_valid_dev(inode
->i_rdev
)) {
4321 raw_inode
->i_block
[0] =
4322 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4323 raw_inode
->i_block
[1] = 0;
4325 raw_inode
->i_block
[0] = 0;
4326 raw_inode
->i_block
[1] =
4327 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4328 raw_inode
->i_block
[2] = 0;
4330 } else if (!ext4_has_inline_data(inode
)) {
4331 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4332 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4335 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4336 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4337 if (ei
->i_extra_isize
) {
4338 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4339 raw_inode
->i_version_hi
=
4340 cpu_to_le32(inode
->i_version
>> 32);
4341 raw_inode
->i_extra_isize
=
4342 cpu_to_le16(ei
->i_extra_isize
);
4345 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4346 spin_unlock(&ei
->i_raw_lock
);
4347 if (inode
->i_sb
->s_flags
& MS_LAZYTIME
)
4348 ext4_update_other_inodes_time(inode
->i_sb
, inode
->i_ino
,
4351 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4352 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4355 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4356 if (set_large_file
) {
4357 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get write access");
4358 err
= ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
);
4361 ext4_update_dynamic_rev(sb
);
4362 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4363 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4364 ext4_handle_sync(handle
);
4365 err
= ext4_handle_dirty_super(handle
, sb
);
4367 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4370 ext4_std_error(inode
->i_sb
, err
);
4375 * ext4_write_inode()
4377 * We are called from a few places:
4379 * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files.
4380 * Here, there will be no transaction running. We wait for any running
4381 * transaction to commit.
4383 * - Within flush work (sys_sync(), kupdate and such).
4384 * We wait on commit, if told to.
4386 * - Within iput_final() -> write_inode_now()
4387 * We wait on commit, if told to.
4389 * In all cases it is actually safe for us to return without doing anything,
4390 * because the inode has been copied into a raw inode buffer in
4391 * ext4_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL
4394 * Note that we are absolutely dependent upon all inode dirtiers doing the
4395 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4396 * which we are interested.
4398 * It would be a bug for them to not do this. The code:
4400 * mark_inode_dirty(inode)
4402 * inode->i_size = expr;
4404 * is in error because write_inode() could occur while `stuff()' is running,
4405 * and the new i_size will be lost. Plus the inode will no longer be on the
4406 * superblock's dirty inode list.
4408 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4412 if (WARN_ON_ONCE(current
->flags
& PF_MEMALLOC
))
4415 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4416 if (ext4_journal_current_handle()) {
4417 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4423 * No need to force transaction in WB_SYNC_NONE mode. Also
4424 * ext4_sync_fs() will force the commit after everything is
4427 if (wbc
->sync_mode
!= WB_SYNC_ALL
|| wbc
->for_sync
)
4430 err
= ext4_force_commit(inode
->i_sb
);
4432 struct ext4_iloc iloc
;
4434 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4438 * sync(2) will flush the whole buffer cache. No need to do
4439 * it here separately for each inode.
4441 if (wbc
->sync_mode
== WB_SYNC_ALL
&& !wbc
->for_sync
)
4442 sync_dirty_buffer(iloc
.bh
);
4443 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4444 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4445 "IO error syncing inode");
4454 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4455 * buffers that are attached to a page stradding i_size and are undergoing
4456 * commit. In that case we have to wait for commit to finish and try again.
4458 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4462 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4463 tid_t commit_tid
= 0;
4466 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4468 * All buffers in the last page remain valid? Then there's nothing to
4469 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4472 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4475 page
= find_lock_page(inode
->i_mapping
,
4476 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4479 ret
= __ext4_journalled_invalidatepage(page
, offset
,
4480 PAGE_CACHE_SIZE
- offset
);
4482 page_cache_release(page
);
4486 read_lock(&journal
->j_state_lock
);
4487 if (journal
->j_committing_transaction
)
4488 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4489 read_unlock(&journal
->j_state_lock
);
4491 jbd2_log_wait_commit(journal
, commit_tid
);
4498 * Called from notify_change.
4500 * We want to trap VFS attempts to truncate the file as soon as
4501 * possible. In particular, we want to make sure that when the VFS
4502 * shrinks i_size, we put the inode on the orphan list and modify
4503 * i_disksize immediately, so that during the subsequent flushing of
4504 * dirty pages and freeing of disk blocks, we can guarantee that any
4505 * commit will leave the blocks being flushed in an unused state on
4506 * disk. (On recovery, the inode will get truncated and the blocks will
4507 * be freed, so we have a strong guarantee that no future commit will
4508 * leave these blocks visible to the user.)
4510 * Another thing we have to assure is that if we are in ordered mode
4511 * and inode is still attached to the committing transaction, we must
4512 * we start writeout of all the dirty pages which are being truncated.
4513 * This way we are sure that all the data written in the previous
4514 * transaction are already on disk (truncate waits for pages under
4517 * Called with inode->i_mutex down.
4519 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4521 struct inode
*inode
= dentry
->d_inode
;
4524 const unsigned int ia_valid
= attr
->ia_valid
;
4526 error
= inode_change_ok(inode
, attr
);
4530 if (is_quota_modification(inode
, attr
))
4531 dquot_initialize(inode
);
4532 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4533 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4536 /* (user+group)*(old+new) structure, inode write (sb,
4537 * inode block, ? - but truncate inode update has it) */
4538 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4539 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4540 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4541 if (IS_ERR(handle
)) {
4542 error
= PTR_ERR(handle
);
4545 error
= dquot_transfer(inode
, attr
);
4547 ext4_journal_stop(handle
);
4550 /* Update corresponding info in inode so that everything is in
4551 * one transaction */
4552 if (attr
->ia_valid
& ATTR_UID
)
4553 inode
->i_uid
= attr
->ia_uid
;
4554 if (attr
->ia_valid
& ATTR_GID
)
4555 inode
->i_gid
= attr
->ia_gid
;
4556 error
= ext4_mark_inode_dirty(handle
, inode
);
4557 ext4_journal_stop(handle
);
4560 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4563 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4564 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4566 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4570 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4571 inode_inc_iversion(inode
);
4573 if (S_ISREG(inode
->i_mode
) &&
4574 (attr
->ia_size
< inode
->i_size
)) {
4575 if (ext4_should_order_data(inode
)) {
4576 error
= ext4_begin_ordered_truncate(inode
,
4581 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4582 if (IS_ERR(handle
)) {
4583 error
= PTR_ERR(handle
);
4586 if (ext4_handle_valid(handle
)) {
4587 error
= ext4_orphan_add(handle
, inode
);
4590 down_write(&EXT4_I(inode
)->i_data_sem
);
4591 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4592 rc
= ext4_mark_inode_dirty(handle
, inode
);
4596 * We have to update i_size under i_data_sem together
4597 * with i_disksize to avoid races with writeback code
4598 * running ext4_wb_update_i_disksize().
4601 i_size_write(inode
, attr
->ia_size
);
4602 up_write(&EXT4_I(inode
)->i_data_sem
);
4603 ext4_journal_stop(handle
);
4605 ext4_orphan_del(NULL
, inode
);
4609 loff_t oldsize
= inode
->i_size
;
4611 i_size_write(inode
, attr
->ia_size
);
4612 pagecache_isize_extended(inode
, oldsize
, inode
->i_size
);
4616 * Blocks are going to be removed from the inode. Wait
4617 * for dio in flight. Temporarily disable
4618 * dioread_nolock to prevent livelock.
4621 if (!ext4_should_journal_data(inode
)) {
4622 ext4_inode_block_unlocked_dio(inode
);
4623 inode_dio_wait(inode
);
4624 ext4_inode_resume_unlocked_dio(inode
);
4626 ext4_wait_for_tail_page_commit(inode
);
4629 * Truncate pagecache after we've waited for commit
4630 * in data=journal mode to make pages freeable.
4632 truncate_pagecache(inode
, inode
->i_size
);
4635 * We want to call ext4_truncate() even if attr->ia_size ==
4636 * inode->i_size for cases like truncation of fallocated space
4638 if (attr
->ia_valid
& ATTR_SIZE
)
4639 ext4_truncate(inode
);
4642 setattr_copy(inode
, attr
);
4643 mark_inode_dirty(inode
);
4647 * If the call to ext4_truncate failed to get a transaction handle at
4648 * all, we need to clean up the in-core orphan list manually.
4650 if (orphan
&& inode
->i_nlink
)
4651 ext4_orphan_del(NULL
, inode
);
4653 if (!rc
&& (ia_valid
& ATTR_MODE
))
4654 rc
= posix_acl_chmod(inode
, inode
->i_mode
);
4657 ext4_std_error(inode
->i_sb
, error
);
4663 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4666 struct inode
*inode
;
4667 unsigned long long delalloc_blocks
;
4669 inode
= dentry
->d_inode
;
4670 generic_fillattr(inode
, stat
);
4673 * If there is inline data in the inode, the inode will normally not
4674 * have data blocks allocated (it may have an external xattr block).
4675 * Report at least one sector for such files, so tools like tar, rsync,
4676 * others doen't incorrectly think the file is completely sparse.
4678 if (unlikely(ext4_has_inline_data(inode
)))
4679 stat
->blocks
+= (stat
->size
+ 511) >> 9;
4682 * We can't update i_blocks if the block allocation is delayed
4683 * otherwise in the case of system crash before the real block
4684 * allocation is done, we will have i_blocks inconsistent with
4685 * on-disk file blocks.
4686 * We always keep i_blocks updated together with real
4687 * allocation. But to not confuse with user, stat
4688 * will return the blocks that include the delayed allocation
4689 * blocks for this file.
4691 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4692 EXT4_I(inode
)->i_reserved_data_blocks
);
4693 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
- 9);
4697 static int ext4_index_trans_blocks(struct inode
*inode
, int lblocks
,
4700 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4701 return ext4_ind_trans_blocks(inode
, lblocks
);
4702 return ext4_ext_index_trans_blocks(inode
, pextents
);
4706 * Account for index blocks, block groups bitmaps and block group
4707 * descriptor blocks if modify datablocks and index blocks
4708 * worse case, the indexs blocks spread over different block groups
4710 * If datablocks are discontiguous, they are possible to spread over
4711 * different block groups too. If they are contiguous, with flexbg,
4712 * they could still across block group boundary.
4714 * Also account for superblock, inode, quota and xattr blocks
4716 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
4719 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4725 * How many index blocks need to touch to map @lblocks logical blocks
4726 * to @pextents physical extents?
4728 idxblocks
= ext4_index_trans_blocks(inode
, lblocks
, pextents
);
4733 * Now let's see how many group bitmaps and group descriptors need
4736 groups
= idxblocks
+ pextents
;
4738 if (groups
> ngroups
)
4740 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4741 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4743 /* bitmaps and block group descriptor blocks */
4744 ret
+= groups
+ gdpblocks
;
4746 /* Blocks for super block, inode, quota and xattr blocks */
4747 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4753 * Calculate the total number of credits to reserve to fit
4754 * the modification of a single pages into a single transaction,
4755 * which may include multiple chunks of block allocations.
4757 * This could be called via ext4_write_begin()
4759 * We need to consider the worse case, when
4760 * one new block per extent.
4762 int ext4_writepage_trans_blocks(struct inode
*inode
)
4764 int bpp
= ext4_journal_blocks_per_page(inode
);
4767 ret
= ext4_meta_trans_blocks(inode
, bpp
, bpp
);
4769 /* Account for data blocks for journalled mode */
4770 if (ext4_should_journal_data(inode
))
4776 * Calculate the journal credits for a chunk of data modification.
4778 * This is called from DIO, fallocate or whoever calling
4779 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4781 * journal buffers for data blocks are not included here, as DIO
4782 * and fallocate do no need to journal data buffers.
4784 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4786 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4790 * The caller must have previously called ext4_reserve_inode_write().
4791 * Give this, we know that the caller already has write access to iloc->bh.
4793 int ext4_mark_iloc_dirty(handle_t
*handle
,
4794 struct inode
*inode
, struct ext4_iloc
*iloc
)
4798 if (IS_I_VERSION(inode
))
4799 inode_inc_iversion(inode
);
4801 /* the do_update_inode consumes one bh->b_count */
4804 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4805 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4811 * On success, We end up with an outstanding reference count against
4812 * iloc->bh. This _must_ be cleaned up later.
4816 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4817 struct ext4_iloc
*iloc
)
4821 err
= ext4_get_inode_loc(inode
, iloc
);
4823 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4824 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4830 ext4_std_error(inode
->i_sb
, err
);
4835 * Expand an inode by new_extra_isize bytes.
4836 * Returns 0 on success or negative error number on failure.
4838 static int ext4_expand_extra_isize(struct inode
*inode
,
4839 unsigned int new_extra_isize
,
4840 struct ext4_iloc iloc
,
4843 struct ext4_inode
*raw_inode
;
4844 struct ext4_xattr_ibody_header
*header
;
4846 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
4849 raw_inode
= ext4_raw_inode(&iloc
);
4851 header
= IHDR(inode
, raw_inode
);
4853 /* No extended attributes present */
4854 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
4855 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4856 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
4858 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
4862 /* try to expand with EAs present */
4863 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
4868 * What we do here is to mark the in-core inode as clean with respect to inode
4869 * dirtiness (it may still be data-dirty).
4870 * This means that the in-core inode may be reaped by prune_icache
4871 * without having to perform any I/O. This is a very good thing,
4872 * because *any* task may call prune_icache - even ones which
4873 * have a transaction open against a different journal.
4875 * Is this cheating? Not really. Sure, we haven't written the
4876 * inode out, but prune_icache isn't a user-visible syncing function.
4877 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
4878 * we start and wait on commits.
4880 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
4882 struct ext4_iloc iloc
;
4883 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4884 static unsigned int mnt_count
;
4888 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
4889 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
4890 if (ext4_handle_valid(handle
) &&
4891 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
4892 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
4894 * We need extra buffer credits since we may write into EA block
4895 * with this same handle. If journal_extend fails, then it will
4896 * only result in a minor loss of functionality for that inode.
4897 * If this is felt to be critical, then e2fsck should be run to
4898 * force a large enough s_min_extra_isize.
4900 if ((jbd2_journal_extend(handle
,
4901 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
4902 ret
= ext4_expand_extra_isize(inode
,
4903 sbi
->s_want_extra_isize
,
4906 ext4_set_inode_state(inode
,
4907 EXT4_STATE_NO_EXPAND
);
4909 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
4910 ext4_warning(inode
->i_sb
,
4911 "Unable to expand inode %lu. Delete"
4912 " some EAs or run e2fsck.",
4915 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
4921 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
4926 * ext4_dirty_inode() is called from __mark_inode_dirty()
4928 * We're really interested in the case where a file is being extended.
4929 * i_size has been changed by generic_commit_write() and we thus need
4930 * to include the updated inode in the current transaction.
4932 * Also, dquot_alloc_block() will always dirty the inode when blocks
4933 * are allocated to the file.
4935 * If the inode is marked synchronous, we don't honour that here - doing
4936 * so would cause a commit on atime updates, which we don't bother doing.
4937 * We handle synchronous inodes at the highest possible level.
4939 * If only the I_DIRTY_TIME flag is set, we can skip everything. If
4940 * I_DIRTY_TIME and I_DIRTY_SYNC is set, the only inode fields we need
4941 * to copy into the on-disk inode structure are the timestamp files.
4943 void ext4_dirty_inode(struct inode
*inode
, int flags
)
4947 if (flags
== I_DIRTY_TIME
)
4949 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
4953 ext4_mark_inode_dirty(handle
, inode
);
4955 ext4_journal_stop(handle
);
4962 * Bind an inode's backing buffer_head into this transaction, to prevent
4963 * it from being flushed to disk early. Unlike
4964 * ext4_reserve_inode_write, this leaves behind no bh reference and
4965 * returns no iloc structure, so the caller needs to repeat the iloc
4966 * lookup to mark the inode dirty later.
4968 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
4970 struct ext4_iloc iloc
;
4974 err
= ext4_get_inode_loc(inode
, &iloc
);
4976 BUFFER_TRACE(iloc
.bh
, "get_write_access");
4977 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
4979 err
= ext4_handle_dirty_metadata(handle
,
4985 ext4_std_error(inode
->i_sb
, err
);
4990 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
4997 * We have to be very careful here: changing a data block's
4998 * journaling status dynamically is dangerous. If we write a
4999 * data block to the journal, change the status and then delete
5000 * that block, we risk forgetting to revoke the old log record
5001 * from the journal and so a subsequent replay can corrupt data.
5002 * So, first we make sure that the journal is empty and that
5003 * nobody is changing anything.
5006 journal
= EXT4_JOURNAL(inode
);
5009 if (is_journal_aborted(journal
))
5011 /* We have to allocate physical blocks for delalloc blocks
5012 * before flushing journal. otherwise delalloc blocks can not
5013 * be allocated any more. even more truncate on delalloc blocks
5014 * could trigger BUG by flushing delalloc blocks in journal.
5015 * There is no delalloc block in non-journal data mode.
5017 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5018 err
= ext4_alloc_da_blocks(inode
);
5023 /* Wait for all existing dio workers */
5024 ext4_inode_block_unlocked_dio(inode
);
5025 inode_dio_wait(inode
);
5027 jbd2_journal_lock_updates(journal
);
5030 * OK, there are no updates running now, and all cached data is
5031 * synced to disk. We are now in a completely consistent state
5032 * which doesn't have anything in the journal, and we know that
5033 * no filesystem updates are running, so it is safe to modify
5034 * the inode's in-core data-journaling state flag now.
5038 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5040 err
= jbd2_journal_flush(journal
);
5042 jbd2_journal_unlock_updates(journal
);
5043 ext4_inode_resume_unlocked_dio(inode
);
5046 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5048 ext4_set_aops(inode
);
5050 jbd2_journal_unlock_updates(journal
);
5051 ext4_inode_resume_unlocked_dio(inode
);
5053 /* Finally we can mark the inode as dirty. */
5055 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5057 return PTR_ERR(handle
);
5059 err
= ext4_mark_inode_dirty(handle
, inode
);
5060 ext4_handle_sync(handle
);
5061 ext4_journal_stop(handle
);
5062 ext4_std_error(inode
->i_sb
, err
);
5067 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5069 return !buffer_mapped(bh
);
5072 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5074 struct page
*page
= vmf
->page
;
5078 struct file
*file
= vma
->vm_file
;
5079 struct inode
*inode
= file_inode(file
);
5080 struct address_space
*mapping
= inode
->i_mapping
;
5082 get_block_t
*get_block
;
5085 sb_start_pagefault(inode
->i_sb
);
5086 file_update_time(vma
->vm_file
);
5087 /* Delalloc case is easy... */
5088 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5089 !ext4_should_journal_data(inode
) &&
5090 !ext4_nonda_switch(inode
->i_sb
)) {
5092 ret
= __block_page_mkwrite(vma
, vmf
,
5093 ext4_da_get_block_prep
);
5094 } while (ret
== -ENOSPC
&&
5095 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5100 size
= i_size_read(inode
);
5101 /* Page got truncated from under us? */
5102 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5104 ret
= VM_FAULT_NOPAGE
;
5108 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5109 len
= size
& ~PAGE_CACHE_MASK
;
5111 len
= PAGE_CACHE_SIZE
;
5113 * Return if we have all the buffers mapped. This avoids the need to do
5114 * journal_start/journal_stop which can block and take a long time
5116 if (page_has_buffers(page
)) {
5117 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5119 ext4_bh_unmapped
)) {
5120 /* Wait so that we don't change page under IO */
5121 wait_for_stable_page(page
);
5122 ret
= VM_FAULT_LOCKED
;
5127 /* OK, we need to fill the hole... */
5128 if (ext4_should_dioread_nolock(inode
))
5129 get_block
= ext4_get_block_write
;
5131 get_block
= ext4_get_block
;
5133 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5134 ext4_writepage_trans_blocks(inode
));
5135 if (IS_ERR(handle
)) {
5136 ret
= VM_FAULT_SIGBUS
;
5139 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5140 if (!ret
&& ext4_should_journal_data(inode
)) {
5141 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5142 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5144 ret
= VM_FAULT_SIGBUS
;
5145 ext4_journal_stop(handle
);
5148 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5150 ext4_journal_stop(handle
);
5151 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5154 ret
= block_page_mkwrite_return(ret
);
5156 sb_end_pagefault(inode
->i_sb
);