2 * linux/fs/ext4/inode.c
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
11 * linux/fs/minix/inode.c
13 * Copyright (C) 1991, 1992 Linus Torvalds
15 * 64-bit file support on 64-bit platforms by Jakub Jelinek
16 * (jj@sunsite.ms.mff.cuni.cz)
18 * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
22 #include <linux/time.h>
23 #include <linux/jbd2.h>
24 #include <linux/highuid.h>
25 #include <linux/pagemap.h>
26 #include <linux/quotaops.h>
27 #include <linux/string.h>
28 #include <linux/buffer_head.h>
29 #include <linux/writeback.h>
30 #include <linux/pagevec.h>
31 #include <linux/mpage.h>
32 #include <linux/namei.h>
33 #include <linux/uio.h>
34 #include <linux/bio.h>
35 #include <linux/workqueue.h>
36 #include <linux/kernel.h>
37 #include <linux/printk.h>
38 #include <linux/slab.h>
39 #include <linux/ratelimit.h>
40 #include <linux/aio.h>
41 #include <linux/bitops.h>
43 #include "ext4_jbd2.h"
48 #include <trace/events/ext4.h>
50 #define MPAGE_DA_EXTENT_TAIL 0x01
52 static __u32
ext4_inode_csum(struct inode
*inode
, struct ext4_inode
*raw
,
53 struct ext4_inode_info
*ei
)
55 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
60 csum_lo
= le16_to_cpu(raw
->i_checksum_lo
);
61 raw
->i_checksum_lo
= 0;
62 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
63 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
)) {
64 csum_hi
= le16_to_cpu(raw
->i_checksum_hi
);
65 raw
->i_checksum_hi
= 0;
68 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)raw
,
69 EXT4_INODE_SIZE(inode
->i_sb
));
71 raw
->i_checksum_lo
= cpu_to_le16(csum_lo
);
72 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
73 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
74 raw
->i_checksum_hi
= cpu_to_le16(csum_hi
);
79 static int ext4_inode_csum_verify(struct inode
*inode
, struct ext4_inode
*raw
,
80 struct ext4_inode_info
*ei
)
82 __u32 provided
, calculated
;
84 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
85 cpu_to_le32(EXT4_OS_LINUX
) ||
86 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
87 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
90 provided
= le16_to_cpu(raw
->i_checksum_lo
);
91 calculated
= ext4_inode_csum(inode
, raw
, ei
);
92 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
93 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
94 provided
|= ((__u32
)le16_to_cpu(raw
->i_checksum_hi
)) << 16;
98 return provided
== calculated
;
101 static void ext4_inode_csum_set(struct inode
*inode
, struct ext4_inode
*raw
,
102 struct ext4_inode_info
*ei
)
106 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
107 cpu_to_le32(EXT4_OS_LINUX
) ||
108 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
109 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
112 csum
= ext4_inode_csum(inode
, raw
, ei
);
113 raw
->i_checksum_lo
= cpu_to_le16(csum
& 0xFFFF);
114 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
115 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
116 raw
->i_checksum_hi
= cpu_to_le16(csum
>> 16);
119 static inline int ext4_begin_ordered_truncate(struct inode
*inode
,
122 trace_ext4_begin_ordered_truncate(inode
, new_size
);
124 * If jinode is zero, then we never opened the file for
125 * writing, so there's no need to call
126 * jbd2_journal_begin_ordered_truncate() since there's no
127 * outstanding writes we need to flush.
129 if (!EXT4_I(inode
)->jinode
)
131 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode
),
132 EXT4_I(inode
)->jinode
,
136 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
137 unsigned int length
);
138 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
139 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
140 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
144 * Test whether an inode is a fast symlink.
146 static int ext4_inode_is_fast_symlink(struct inode
*inode
)
148 int ea_blocks
= EXT4_I(inode
)->i_file_acl
?
149 EXT4_CLUSTER_SIZE(inode
->i_sb
) >> 9 : 0;
151 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
155 * Restart the transaction associated with *handle. This does a commit,
156 * so before we call here everything must be consistently dirtied against
159 int ext4_truncate_restart_trans(handle_t
*handle
, struct inode
*inode
,
165 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
166 * moment, get_block can be called only for blocks inside i_size since
167 * page cache has been already dropped and writes are blocked by
168 * i_mutex. So we can safely drop the i_data_sem here.
170 BUG_ON(EXT4_JOURNAL(inode
) == NULL
);
171 jbd_debug(2, "restarting handle %p\n", handle
);
172 up_write(&EXT4_I(inode
)->i_data_sem
);
173 ret
= ext4_journal_restart(handle
, nblocks
);
174 down_write(&EXT4_I(inode
)->i_data_sem
);
175 ext4_discard_preallocations(inode
);
181 * Called at the last iput() if i_nlink is zero.
183 void ext4_evict_inode(struct inode
*inode
)
188 trace_ext4_evict_inode(inode
);
190 if (inode
->i_nlink
) {
192 * When journalling data dirty buffers are tracked only in the
193 * journal. So although mm thinks everything is clean and
194 * ready for reaping the inode might still have some pages to
195 * write in the running transaction or waiting to be
196 * checkpointed. Thus calling jbd2_journal_invalidatepage()
197 * (via truncate_inode_pages()) to discard these buffers can
198 * cause data loss. Also even if we did not discard these
199 * buffers, we would have no way to find them after the inode
200 * is reaped and thus user could see stale data if he tries to
201 * read them before the transaction is checkpointed. So be
202 * careful and force everything to disk here... We use
203 * ei->i_datasync_tid to store the newest transaction
204 * containing inode's data.
206 * Note that directories do not have this problem because they
207 * don't use page cache.
209 if (ext4_should_journal_data(inode
) &&
210 (S_ISLNK(inode
->i_mode
) || S_ISREG(inode
->i_mode
)) &&
211 inode
->i_ino
!= EXT4_JOURNAL_INO
) {
212 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
213 tid_t commit_tid
= EXT4_I(inode
)->i_datasync_tid
;
215 jbd2_complete_transaction(journal
, commit_tid
);
216 filemap_write_and_wait(&inode
->i_data
);
218 truncate_inode_pages_final(&inode
->i_data
);
220 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
224 if (!is_bad_inode(inode
))
225 dquot_initialize(inode
);
227 if (ext4_should_order_data(inode
))
228 ext4_begin_ordered_truncate(inode
, 0);
229 truncate_inode_pages_final(&inode
->i_data
);
231 WARN_ON(atomic_read(&EXT4_I(inode
)->i_ioend_count
));
232 if (is_bad_inode(inode
))
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 * Calculate the number of metadata blocks need to reserve
326 * to allocate a block located at @lblock
328 static int ext4_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
330 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
331 return ext4_ext_calc_metadata_amount(inode
, lblock
);
333 return ext4_ind_calc_metadata_amount(inode
, lblock
);
337 * Called with i_data_sem down, which is important since we can call
338 * ext4_discard_preallocations() from here.
340 void ext4_da_update_reserve_space(struct inode
*inode
,
341 int used
, int quota_claim
)
343 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
344 struct ext4_inode_info
*ei
= EXT4_I(inode
);
346 spin_lock(&ei
->i_block_reservation_lock
);
347 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
348 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
349 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
350 "with only %d reserved data blocks",
351 __func__
, inode
->i_ino
, used
,
352 ei
->i_reserved_data_blocks
);
354 used
= ei
->i_reserved_data_blocks
;
357 if (unlikely(ei
->i_allocated_meta_blocks
> ei
->i_reserved_meta_blocks
)) {
358 ext4_warning(inode
->i_sb
, "ino %lu, allocated %d "
359 "with only %d reserved metadata blocks "
360 "(releasing %d blocks with reserved %d data blocks)",
361 inode
->i_ino
, ei
->i_allocated_meta_blocks
,
362 ei
->i_reserved_meta_blocks
, used
,
363 ei
->i_reserved_data_blocks
);
365 ei
->i_allocated_meta_blocks
= ei
->i_reserved_meta_blocks
;
368 /* Update per-inode reservations */
369 ei
->i_reserved_data_blocks
-= used
;
370 ei
->i_reserved_meta_blocks
-= ei
->i_allocated_meta_blocks
;
371 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
372 used
+ ei
->i_allocated_meta_blocks
);
373 ei
->i_allocated_meta_blocks
= 0;
375 if (ei
->i_reserved_data_blocks
== 0) {
377 * We can release all of the reserved metadata blocks
378 * only when we have written all of the delayed
381 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
382 ei
->i_reserved_meta_blocks
);
383 ei
->i_reserved_meta_blocks
= 0;
384 ei
->i_da_metadata_calc_len
= 0;
386 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
388 /* Update quota subsystem for data blocks */
390 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
393 * We did fallocate with an offset that is already delayed
394 * allocated. So on delayed allocated writeback we should
395 * not re-claim the quota for fallocated blocks.
397 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
401 * If we have done all the pending block allocations and if
402 * there aren't any writers on the inode, we can discard the
403 * inode's preallocations.
405 if ((ei
->i_reserved_data_blocks
== 0) &&
406 (atomic_read(&inode
->i_writecount
) == 0))
407 ext4_discard_preallocations(inode
);
410 static int __check_block_validity(struct inode
*inode
, const char *func
,
412 struct ext4_map_blocks
*map
)
414 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
416 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
417 "lblock %lu mapped to illegal pblock "
418 "(length %d)", (unsigned long) map
->m_lblk
,
425 #define check_block_validity(inode, map) \
426 __check_block_validity((inode), __func__, __LINE__, (map))
428 #ifdef ES_AGGRESSIVE_TEST
429 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
431 struct ext4_map_blocks
*es_map
,
432 struct ext4_map_blocks
*map
,
439 * There is a race window that the result is not the same.
440 * e.g. xfstests #223 when dioread_nolock enables. The reason
441 * is that we lookup a block mapping in extent status tree with
442 * out taking i_data_sem. So at the time the unwritten extent
443 * could be converted.
445 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
446 down_read((&EXT4_I(inode
)->i_data_sem
));
447 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
448 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
449 EXT4_GET_BLOCKS_KEEP_SIZE
);
451 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
452 EXT4_GET_BLOCKS_KEEP_SIZE
);
454 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
455 up_read((&EXT4_I(inode
)->i_data_sem
));
457 * Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
458 * because it shouldn't be marked in es_map->m_flags.
460 map
->m_flags
&= ~(EXT4_MAP_FROM_CLUSTER
| EXT4_MAP_BOUNDARY
);
463 * We don't check m_len because extent will be collpased in status
464 * tree. So the m_len might not equal.
466 if (es_map
->m_lblk
!= map
->m_lblk
||
467 es_map
->m_flags
!= map
->m_flags
||
468 es_map
->m_pblk
!= map
->m_pblk
) {
469 printk("ES cache assertion failed for inode: %lu "
470 "es_cached ex [%d/%d/%llu/%x] != "
471 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
472 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
473 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
474 map
->m_len
, map
->m_pblk
, map
->m_flags
,
478 #endif /* ES_AGGRESSIVE_TEST */
481 * The ext4_map_blocks() function tries to look up the requested blocks,
482 * and returns if the blocks are already mapped.
484 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
485 * and store the allocated blocks in the result buffer head and mark it
488 * If file type is extents based, it will call ext4_ext_map_blocks(),
489 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
492 * On success, it returns the number of blocks being mapped or allocate.
493 * if create==0 and the blocks are pre-allocated and uninitialized block,
494 * the result buffer head is unmapped. If the create ==1, it will make sure
495 * the buffer head is mapped.
497 * It returns 0 if plain look up failed (blocks have not been allocated), in
498 * that case, buffer head is unmapped
500 * It returns the error in case of allocation failure.
502 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
503 struct ext4_map_blocks
*map
, int flags
)
505 struct extent_status es
;
508 #ifdef ES_AGGRESSIVE_TEST
509 struct ext4_map_blocks orig_map
;
511 memcpy(&orig_map
, map
, sizeof(*map
));
515 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
516 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
517 (unsigned long) map
->m_lblk
);
520 * ext4_map_blocks returns an int, and m_len is an unsigned int
522 if (unlikely(map
->m_len
> INT_MAX
))
523 map
->m_len
= INT_MAX
;
525 /* We can handle the block number less than EXT_MAX_BLOCKS */
526 if (unlikely(map
->m_lblk
>= EXT_MAX_BLOCKS
))
529 /* Lookup extent status tree firstly */
530 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
531 ext4_es_lru_add(inode
);
532 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
533 map
->m_pblk
= ext4_es_pblock(&es
) +
534 map
->m_lblk
- es
.es_lblk
;
535 map
->m_flags
|= ext4_es_is_written(&es
) ?
536 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
537 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
538 if (retval
> map
->m_len
)
541 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
546 #ifdef ES_AGGRESSIVE_TEST
547 ext4_map_blocks_es_recheck(handle
, inode
, map
,
554 * Try to see if we can get the block without requesting a new
557 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
558 down_read((&EXT4_I(inode
)->i_data_sem
));
559 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
560 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
561 EXT4_GET_BLOCKS_KEEP_SIZE
);
563 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
564 EXT4_GET_BLOCKS_KEEP_SIZE
);
569 if (unlikely(retval
!= map
->m_len
)) {
570 ext4_warning(inode
->i_sb
,
571 "ES len assertion failed for inode "
572 "%lu: retval %d != map->m_len %d",
573 inode
->i_ino
, retval
, map
->m_len
);
577 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
578 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
579 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
580 ext4_find_delalloc_range(inode
, map
->m_lblk
,
581 map
->m_lblk
+ map
->m_len
- 1))
582 status
|= EXTENT_STATUS_DELAYED
;
583 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
584 map
->m_len
, map
->m_pblk
, status
);
588 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
589 up_read((&EXT4_I(inode
)->i_data_sem
));
592 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
593 ret
= check_block_validity(inode
, map
);
598 /* If it is only a block(s) look up */
599 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
603 * Returns if the blocks have already allocated
605 * Note that if blocks have been preallocated
606 * ext4_ext_get_block() returns the create = 0
607 * with buffer head unmapped.
609 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
611 * If we need to convert extent to unwritten
612 * we continue and do the actual work in
613 * ext4_ext_map_blocks()
615 if (!(flags
& EXT4_GET_BLOCKS_CONVERT_UNWRITTEN
))
619 * Here we clear m_flags because after allocating an new extent,
620 * it will be set again.
622 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
625 * New blocks allocate and/or writing to uninitialized extent
626 * will possibly result in updating i_data, so we take
627 * the write lock of i_data_sem, and call get_blocks()
628 * with create == 1 flag.
630 down_write((&EXT4_I(inode
)->i_data_sem
));
633 * if the caller is from delayed allocation writeout path
634 * we have already reserved fs blocks for allocation
635 * let the underlying get_block() function know to
636 * avoid double accounting
638 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
639 ext4_set_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
641 * We need to check for EXT4 here because migrate
642 * could have changed the inode type in between
644 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
645 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
647 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
649 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
651 * We allocated new blocks which will result in
652 * i_data's format changing. Force the migrate
653 * to fail by clearing migrate flags
655 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
659 * Update reserved blocks/metadata blocks after successful
660 * block allocation which had been deferred till now. We don't
661 * support fallocate for non extent files. So we can update
662 * reserve space here.
665 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
666 ext4_da_update_reserve_space(inode
, retval
, 1);
668 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
669 ext4_clear_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
674 if (unlikely(retval
!= map
->m_len
)) {
675 ext4_warning(inode
->i_sb
,
676 "ES len assertion failed for inode "
677 "%lu: retval %d != map->m_len %d",
678 inode
->i_ino
, retval
, map
->m_len
);
683 * If the extent has been zeroed out, we don't need to update
684 * extent status tree.
686 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
687 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
688 if (ext4_es_is_written(&es
))
691 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
692 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
693 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
694 ext4_find_delalloc_range(inode
, map
->m_lblk
,
695 map
->m_lblk
+ map
->m_len
- 1))
696 status
|= EXTENT_STATUS_DELAYED
;
697 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
698 map
->m_pblk
, status
);
704 up_write((&EXT4_I(inode
)->i_data_sem
));
705 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
706 ret
= check_block_validity(inode
, map
);
713 /* Maximum number of blocks we map for direct IO at once. */
714 #define DIO_MAX_BLOCKS 4096
716 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
717 struct buffer_head
*bh
, int flags
)
719 handle_t
*handle
= ext4_journal_current_handle();
720 struct ext4_map_blocks map
;
721 int ret
= 0, started
= 0;
724 if (ext4_has_inline_data(inode
))
728 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
730 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
731 /* Direct IO write... */
732 if (map
.m_len
> DIO_MAX_BLOCKS
)
733 map
.m_len
= DIO_MAX_BLOCKS
;
734 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
735 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
737 if (IS_ERR(handle
)) {
738 ret
= PTR_ERR(handle
);
744 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
746 ext4_io_end_t
*io_end
= ext4_inode_aio(inode
);
748 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
749 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
750 if (io_end
&& io_end
->flag
& EXT4_IO_END_UNWRITTEN
)
751 set_buffer_defer_completion(bh
);
752 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
756 ext4_journal_stop(handle
);
760 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
761 struct buffer_head
*bh
, int create
)
763 return _ext4_get_block(inode
, iblock
, bh
,
764 create
? EXT4_GET_BLOCKS_CREATE
: 0);
768 * `handle' can be NULL if create is zero
770 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
771 ext4_lblk_t block
, int create
, int *errp
)
773 struct ext4_map_blocks map
;
774 struct buffer_head
*bh
;
777 J_ASSERT(handle
!= NULL
|| create
== 0);
781 err
= ext4_map_blocks(handle
, inode
, &map
,
782 create
? EXT4_GET_BLOCKS_CREATE
: 0);
784 /* ensure we send some value back into *errp */
787 if (create
&& err
== 0)
788 err
= -ENOSPC
; /* should never happen */
794 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
799 if (map
.m_flags
& EXT4_MAP_NEW
) {
800 J_ASSERT(create
!= 0);
801 J_ASSERT(handle
!= NULL
);
804 * Now that we do not always journal data, we should
805 * keep in mind whether this should always journal the
806 * new buffer as metadata. For now, regular file
807 * writes use ext4_get_block instead, so it's not a
811 BUFFER_TRACE(bh
, "call get_create_access");
812 fatal
= ext4_journal_get_create_access(handle
, bh
);
813 if (!fatal
&& !buffer_uptodate(bh
)) {
814 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
815 set_buffer_uptodate(bh
);
818 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
819 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
823 BUFFER_TRACE(bh
, "not a new buffer");
833 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
834 ext4_lblk_t block
, int create
, int *err
)
836 struct buffer_head
*bh
;
838 bh
= ext4_getblk(handle
, inode
, block
, create
, err
);
841 if (buffer_uptodate(bh
))
843 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
845 if (buffer_uptodate(bh
))
852 int ext4_walk_page_buffers(handle_t
*handle
,
853 struct buffer_head
*head
,
857 int (*fn
)(handle_t
*handle
,
858 struct buffer_head
*bh
))
860 struct buffer_head
*bh
;
861 unsigned block_start
, block_end
;
862 unsigned blocksize
= head
->b_size
;
864 struct buffer_head
*next
;
866 for (bh
= head
, block_start
= 0;
867 ret
== 0 && (bh
!= head
|| !block_start
);
868 block_start
= block_end
, bh
= next
) {
869 next
= bh
->b_this_page
;
870 block_end
= block_start
+ blocksize
;
871 if (block_end
<= from
|| block_start
>= to
) {
872 if (partial
&& !buffer_uptodate(bh
))
876 err
= (*fn
)(handle
, bh
);
884 * To preserve ordering, it is essential that the hole instantiation and
885 * the data write be encapsulated in a single transaction. We cannot
886 * close off a transaction and start a new one between the ext4_get_block()
887 * and the commit_write(). So doing the jbd2_journal_start at the start of
888 * prepare_write() is the right place.
890 * Also, this function can nest inside ext4_writepage(). In that case, we
891 * *know* that ext4_writepage() has generated enough buffer credits to do the
892 * whole page. So we won't block on the journal in that case, which is good,
893 * because the caller may be PF_MEMALLOC.
895 * By accident, ext4 can be reentered when a transaction is open via
896 * quota file writes. If we were to commit the transaction while thus
897 * reentered, there can be a deadlock - we would be holding a quota
898 * lock, and the commit would never complete if another thread had a
899 * transaction open and was blocking on the quota lock - a ranking
902 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
903 * will _not_ run commit under these circumstances because handle->h_ref
904 * is elevated. We'll still have enough credits for the tiny quotafile
907 int do_journal_get_write_access(handle_t
*handle
,
908 struct buffer_head
*bh
)
910 int dirty
= buffer_dirty(bh
);
913 if (!buffer_mapped(bh
) || buffer_freed(bh
))
916 * __block_write_begin() could have dirtied some buffers. Clean
917 * the dirty bit as jbd2_journal_get_write_access() could complain
918 * otherwise about fs integrity issues. Setting of the dirty bit
919 * by __block_write_begin() isn't a real problem here as we clear
920 * the bit before releasing a page lock and thus writeback cannot
921 * ever write the buffer.
924 clear_buffer_dirty(bh
);
925 ret
= ext4_journal_get_write_access(handle
, bh
);
927 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
931 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
932 struct buffer_head
*bh_result
, int create
);
933 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
934 loff_t pos
, unsigned len
, unsigned flags
,
935 struct page
**pagep
, void **fsdata
)
937 struct inode
*inode
= mapping
->host
;
938 int ret
, needed_blocks
;
945 trace_ext4_write_begin(inode
, pos
, len
, flags
);
947 * Reserve one block more for addition to orphan list in case
948 * we allocate blocks but write fails for some reason
950 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
951 index
= pos
>> PAGE_CACHE_SHIFT
;
952 from
= pos
& (PAGE_CACHE_SIZE
- 1);
955 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
956 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
965 * grab_cache_page_write_begin() can take a long time if the
966 * system is thrashing due to memory pressure, or if the page
967 * is being written back. So grab it first before we start
968 * the transaction handle. This also allows us to allocate
969 * the page (if needed) without using GFP_NOFS.
972 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
978 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
979 if (IS_ERR(handle
)) {
980 page_cache_release(page
);
981 return PTR_ERR(handle
);
985 if (page
->mapping
!= mapping
) {
986 /* The page got truncated from under us */
988 page_cache_release(page
);
989 ext4_journal_stop(handle
);
992 /* In case writeback began while the page was unlocked */
993 wait_for_stable_page(page
);
995 if (ext4_should_dioread_nolock(inode
))
996 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
998 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
1000 if (!ret
&& ext4_should_journal_data(inode
)) {
1001 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
1003 do_journal_get_write_access
);
1009 * __block_write_begin may have instantiated a few blocks
1010 * outside i_size. Trim these off again. Don't need
1011 * i_size_read because we hold i_mutex.
1013 * Add inode to orphan list in case we crash before
1016 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1017 ext4_orphan_add(handle
, inode
);
1019 ext4_journal_stop(handle
);
1020 if (pos
+ len
> inode
->i_size
) {
1021 ext4_truncate_failed_write(inode
);
1023 * If truncate failed early the inode might
1024 * still be on the orphan list; we need to
1025 * make sure the inode is removed from the
1026 * orphan list in that case.
1029 ext4_orphan_del(NULL
, inode
);
1032 if (ret
== -ENOSPC
&&
1033 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
1035 page_cache_release(page
);
1042 /* For write_end() in data=journal mode */
1043 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1046 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1048 set_buffer_uptodate(bh
);
1049 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1050 clear_buffer_meta(bh
);
1051 clear_buffer_prio(bh
);
1056 * We need to pick up the new inode size which generic_commit_write gave us
1057 * `file' can be NULL - eg, when called from page_symlink().
1059 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1060 * buffers are managed internally.
1062 static int ext4_write_end(struct file
*file
,
1063 struct address_space
*mapping
,
1064 loff_t pos
, unsigned len
, unsigned copied
,
1065 struct page
*page
, void *fsdata
)
1067 handle_t
*handle
= ext4_journal_current_handle();
1068 struct inode
*inode
= mapping
->host
;
1070 int i_size_changed
= 0;
1072 trace_ext4_write_end(inode
, pos
, len
, copied
);
1073 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1074 ret
= ext4_jbd2_file_inode(handle
, inode
);
1077 page_cache_release(page
);
1082 if (ext4_has_inline_data(inode
)) {
1083 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1089 copied
= block_write_end(file
, mapping
, pos
,
1090 len
, copied
, page
, fsdata
);
1093 * No need to use i_size_read() here, the i_size
1094 * cannot change under us because we hole i_mutex.
1096 * But it's important to update i_size while still holding page lock:
1097 * page writeout could otherwise come in and zero beyond i_size.
1099 if (pos
+ copied
> inode
->i_size
) {
1100 i_size_write(inode
, pos
+ copied
);
1104 if (pos
+ copied
> EXT4_I(inode
)->i_disksize
) {
1105 /* We need to mark inode dirty even if
1106 * new_i_size is less that inode->i_size
1107 * but greater than i_disksize. (hint delalloc)
1109 ext4_update_i_disksize(inode
, (pos
+ copied
));
1113 page_cache_release(page
);
1116 * Don't mark the inode dirty under page lock. First, it unnecessarily
1117 * makes the holding time of page lock longer. Second, it forces lock
1118 * ordering of page lock and transaction start for journaling
1122 ext4_mark_inode_dirty(handle
, inode
);
1124 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1125 /* if we have allocated more blocks and copied
1126 * less. We will have blocks allocated outside
1127 * inode->i_size. So truncate them
1129 ext4_orphan_add(handle
, inode
);
1131 ret2
= ext4_journal_stop(handle
);
1135 if (pos
+ len
> inode
->i_size
) {
1136 ext4_truncate_failed_write(inode
);
1138 * If truncate failed early the inode might still be
1139 * on the orphan list; we need to make sure the inode
1140 * is removed from the orphan list in that case.
1143 ext4_orphan_del(NULL
, inode
);
1146 return ret
? ret
: copied
;
1149 static int ext4_journalled_write_end(struct file
*file
,
1150 struct address_space
*mapping
,
1151 loff_t pos
, unsigned len
, unsigned copied
,
1152 struct page
*page
, void *fsdata
)
1154 handle_t
*handle
= ext4_journal_current_handle();
1155 struct inode
*inode
= mapping
->host
;
1161 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1162 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1165 BUG_ON(!ext4_handle_valid(handle
));
1167 if (ext4_has_inline_data(inode
))
1168 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1172 if (!PageUptodate(page
))
1174 page_zero_new_buffers(page
, from
+copied
, to
);
1177 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1178 to
, &partial
, write_end_fn
);
1180 SetPageUptodate(page
);
1182 new_i_size
= pos
+ copied
;
1183 if (new_i_size
> inode
->i_size
)
1184 i_size_write(inode
, pos
+copied
);
1185 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1186 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1187 if (new_i_size
> EXT4_I(inode
)->i_disksize
) {
1188 ext4_update_i_disksize(inode
, new_i_size
);
1189 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1195 page_cache_release(page
);
1196 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1197 /* if we have allocated more blocks and copied
1198 * less. We will have blocks allocated outside
1199 * inode->i_size. So truncate them
1201 ext4_orphan_add(handle
, inode
);
1203 ret2
= ext4_journal_stop(handle
);
1206 if (pos
+ len
> inode
->i_size
) {
1207 ext4_truncate_failed_write(inode
);
1209 * If truncate failed early the inode might still be
1210 * on the orphan list; we need to make sure the inode
1211 * is removed from the orphan list in that case.
1214 ext4_orphan_del(NULL
, inode
);
1217 return ret
? ret
: copied
;
1221 * Reserve a metadata for a single block located at lblock
1223 static int ext4_da_reserve_metadata(struct inode
*inode
, ext4_lblk_t lblock
)
1225 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1226 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1227 unsigned int md_needed
;
1228 ext4_lblk_t save_last_lblock
;
1232 * recalculate the amount of metadata blocks to reserve
1233 * in order to allocate nrblocks
1234 * worse case is one extent per block
1236 spin_lock(&ei
->i_block_reservation_lock
);
1238 * ext4_calc_metadata_amount() has side effects, which we have
1239 * to be prepared undo if we fail to claim space.
1241 save_len
= ei
->i_da_metadata_calc_len
;
1242 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1243 md_needed
= EXT4_NUM_B2C(sbi
,
1244 ext4_calc_metadata_amount(inode
, lblock
));
1245 trace_ext4_da_reserve_space(inode
, md_needed
);
1248 * We do still charge estimated metadata to the sb though;
1249 * we cannot afford to run out of free blocks.
1251 if (ext4_claim_free_clusters(sbi
, md_needed
, 0)) {
1252 ei
->i_da_metadata_calc_len
= save_len
;
1253 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1254 spin_unlock(&ei
->i_block_reservation_lock
);
1257 ei
->i_reserved_meta_blocks
+= md_needed
;
1258 spin_unlock(&ei
->i_block_reservation_lock
);
1260 return 0; /* success */
1264 * Reserve a single cluster located at lblock
1266 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1268 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1269 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1270 unsigned int md_needed
;
1272 ext4_lblk_t save_last_lblock
;
1276 * We will charge metadata quota at writeout time; this saves
1277 * us from metadata over-estimation, though we may go over by
1278 * a small amount in the end. Here we just reserve for data.
1280 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1285 * recalculate the amount of metadata blocks to reserve
1286 * in order to allocate nrblocks
1287 * worse case is one extent per block
1289 spin_lock(&ei
->i_block_reservation_lock
);
1291 * ext4_calc_metadata_amount() has side effects, which we have
1292 * to be prepared undo if we fail to claim space.
1294 save_len
= ei
->i_da_metadata_calc_len
;
1295 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1296 md_needed
= EXT4_NUM_B2C(sbi
,
1297 ext4_calc_metadata_amount(inode
, lblock
));
1298 trace_ext4_da_reserve_space(inode
, md_needed
);
1301 * We do still charge estimated metadata to the sb though;
1302 * we cannot afford to run out of free blocks.
1304 if (ext4_claim_free_clusters(sbi
, md_needed
+ 1, 0)) {
1305 ei
->i_da_metadata_calc_len
= save_len
;
1306 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1307 spin_unlock(&ei
->i_block_reservation_lock
);
1308 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1311 ei
->i_reserved_data_blocks
++;
1312 ei
->i_reserved_meta_blocks
+= md_needed
;
1313 spin_unlock(&ei
->i_block_reservation_lock
);
1315 return 0; /* success */
1318 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1320 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1321 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1324 return; /* Nothing to release, exit */
1326 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1328 trace_ext4_da_release_space(inode
, to_free
);
1329 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1331 * if there aren't enough reserved blocks, then the
1332 * counter is messed up somewhere. Since this
1333 * function is called from invalidate page, it's
1334 * harmless to return without any action.
1336 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1337 "ino %lu, to_free %d with only %d reserved "
1338 "data blocks", inode
->i_ino
, to_free
,
1339 ei
->i_reserved_data_blocks
);
1341 to_free
= ei
->i_reserved_data_blocks
;
1343 ei
->i_reserved_data_blocks
-= to_free
;
1345 if (ei
->i_reserved_data_blocks
== 0) {
1347 * We can release all of the reserved metadata blocks
1348 * only when we have written all of the delayed
1349 * allocation blocks.
1350 * Note that in case of bigalloc, i_reserved_meta_blocks,
1351 * i_reserved_data_blocks, etc. refer to number of clusters.
1353 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
1354 ei
->i_reserved_meta_blocks
);
1355 ei
->i_reserved_meta_blocks
= 0;
1356 ei
->i_da_metadata_calc_len
= 0;
1359 /* update fs dirty data blocks counter */
1360 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1362 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1364 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1367 static void ext4_da_page_release_reservation(struct page
*page
,
1368 unsigned int offset
,
1369 unsigned int length
)
1372 struct buffer_head
*head
, *bh
;
1373 unsigned int curr_off
= 0;
1374 struct inode
*inode
= page
->mapping
->host
;
1375 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1376 unsigned int stop
= offset
+ length
;
1380 BUG_ON(stop
> PAGE_CACHE_SIZE
|| stop
< length
);
1382 head
= page_buffers(page
);
1385 unsigned int next_off
= curr_off
+ bh
->b_size
;
1387 if (next_off
> stop
)
1390 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1392 clear_buffer_delay(bh
);
1394 curr_off
= next_off
;
1395 } while ((bh
= bh
->b_this_page
) != head
);
1398 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1399 ext4_es_remove_extent(inode
, lblk
, to_release
);
1402 /* If we have released all the blocks belonging to a cluster, then we
1403 * need to release the reserved space for that cluster. */
1404 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1405 while (num_clusters
> 0) {
1406 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1407 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1408 if (sbi
->s_cluster_ratio
== 1 ||
1409 !ext4_find_delalloc_cluster(inode
, lblk
))
1410 ext4_da_release_space(inode
, 1);
1417 * Delayed allocation stuff
1420 struct mpage_da_data
{
1421 struct inode
*inode
;
1422 struct writeback_control
*wbc
;
1424 pgoff_t first_page
; /* The first page to write */
1425 pgoff_t next_page
; /* Current page to examine */
1426 pgoff_t last_page
; /* Last page to examine */
1428 * Extent to map - this can be after first_page because that can be
1429 * fully mapped. We somewhat abuse m_flags to store whether the extent
1430 * is delalloc or unwritten.
1432 struct ext4_map_blocks map
;
1433 struct ext4_io_submit io_submit
; /* IO submission data */
1436 static void mpage_release_unused_pages(struct mpage_da_data
*mpd
,
1441 struct pagevec pvec
;
1442 struct inode
*inode
= mpd
->inode
;
1443 struct address_space
*mapping
= inode
->i_mapping
;
1445 /* This is necessary when next_page == 0. */
1446 if (mpd
->first_page
>= mpd
->next_page
)
1449 index
= mpd
->first_page
;
1450 end
= mpd
->next_page
- 1;
1452 ext4_lblk_t start
, last
;
1453 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1454 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1455 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1458 pagevec_init(&pvec
, 0);
1459 while (index
<= end
) {
1460 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1463 for (i
= 0; i
< nr_pages
; i
++) {
1464 struct page
*page
= pvec
.pages
[i
];
1465 if (page
->index
> end
)
1467 BUG_ON(!PageLocked(page
));
1468 BUG_ON(PageWriteback(page
));
1470 block_invalidatepage(page
, 0, PAGE_CACHE_SIZE
);
1471 ClearPageUptodate(page
);
1475 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1476 pagevec_release(&pvec
);
1480 static void ext4_print_free_blocks(struct inode
*inode
)
1482 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1483 struct super_block
*sb
= inode
->i_sb
;
1484 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1486 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1487 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1488 ext4_count_free_clusters(sb
)));
1489 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1490 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1491 (long long) EXT4_C2B(EXT4_SB(sb
),
1492 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1493 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1494 (long long) EXT4_C2B(EXT4_SB(sb
),
1495 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1496 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1497 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1498 ei
->i_reserved_data_blocks
);
1499 ext4_msg(sb
, KERN_CRIT
, "i_reserved_meta_blocks=%u",
1500 ei
->i_reserved_meta_blocks
);
1501 ext4_msg(sb
, KERN_CRIT
, "i_allocated_meta_blocks=%u",
1502 ei
->i_allocated_meta_blocks
);
1506 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1508 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1512 * This function is grabs code from the very beginning of
1513 * ext4_map_blocks, but assumes that the caller is from delayed write
1514 * time. This function looks up the requested blocks and sets the
1515 * buffer delay bit under the protection of i_data_sem.
1517 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1518 struct ext4_map_blocks
*map
,
1519 struct buffer_head
*bh
)
1521 struct extent_status es
;
1523 sector_t invalid_block
= ~((sector_t
) 0xffff);
1524 #ifdef ES_AGGRESSIVE_TEST
1525 struct ext4_map_blocks orig_map
;
1527 memcpy(&orig_map
, map
, sizeof(*map
));
1530 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1534 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1535 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1536 (unsigned long) map
->m_lblk
);
1538 /* Lookup extent status tree firstly */
1539 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1540 ext4_es_lru_add(inode
);
1541 if (ext4_es_is_hole(&es
)) {
1543 down_read((&EXT4_I(inode
)->i_data_sem
));
1548 * Delayed extent could be allocated by fallocate.
1549 * So we need to check it.
1551 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1552 map_bh(bh
, inode
->i_sb
, invalid_block
);
1554 set_buffer_delay(bh
);
1558 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1559 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1560 if (retval
> map
->m_len
)
1561 retval
= map
->m_len
;
1562 map
->m_len
= retval
;
1563 if (ext4_es_is_written(&es
))
1564 map
->m_flags
|= EXT4_MAP_MAPPED
;
1565 else if (ext4_es_is_unwritten(&es
))
1566 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1570 #ifdef ES_AGGRESSIVE_TEST
1571 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1577 * Try to see if we can get the block without requesting a new
1578 * file system block.
1580 down_read((&EXT4_I(inode
)->i_data_sem
));
1581 if (ext4_has_inline_data(inode
)) {
1583 * We will soon create blocks for this page, and let
1584 * us pretend as if the blocks aren't allocated yet.
1585 * In case of clusters, we have to handle the work
1586 * of mapping from cluster so that the reserved space
1587 * is calculated properly.
1589 if ((EXT4_SB(inode
->i_sb
)->s_cluster_ratio
> 1) &&
1590 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
1591 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
1593 } else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1594 retval
= ext4_ext_map_blocks(NULL
, inode
, map
,
1595 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1597 retval
= ext4_ind_map_blocks(NULL
, inode
, map
,
1598 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1604 * XXX: __block_prepare_write() unmaps passed block,
1608 * If the block was allocated from previously allocated cluster,
1609 * then we don't need to reserve it again. However we still need
1610 * to reserve metadata for every block we're going to write.
1612 if (!(map
->m_flags
& EXT4_MAP_FROM_CLUSTER
)) {
1613 ret
= ext4_da_reserve_space(inode
, iblock
);
1615 /* not enough space to reserve */
1620 ret
= ext4_da_reserve_metadata(inode
, iblock
);
1622 /* not enough space to reserve */
1628 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1629 ~0, EXTENT_STATUS_DELAYED
);
1635 /* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
1636 * and it should not appear on the bh->b_state.
1638 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
1640 map_bh(bh
, inode
->i_sb
, invalid_block
);
1642 set_buffer_delay(bh
);
1643 } else if (retval
> 0) {
1645 unsigned int status
;
1647 if (unlikely(retval
!= map
->m_len
)) {
1648 ext4_warning(inode
->i_sb
,
1649 "ES len assertion failed for inode "
1650 "%lu: retval %d != map->m_len %d",
1651 inode
->i_ino
, retval
, map
->m_len
);
1655 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
1656 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
1657 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1658 map
->m_pblk
, status
);
1664 up_read((&EXT4_I(inode
)->i_data_sem
));
1670 * This is a special get_blocks_t callback which is used by
1671 * ext4_da_write_begin(). It will either return mapped block or
1672 * reserve space for a single block.
1674 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
1675 * We also have b_blocknr = -1 and b_bdev initialized properly
1677 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
1678 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
1679 * initialized properly.
1681 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
1682 struct buffer_head
*bh
, int create
)
1684 struct ext4_map_blocks map
;
1687 BUG_ON(create
== 0);
1688 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
1690 map
.m_lblk
= iblock
;
1694 * first, we need to know whether the block is allocated already
1695 * preallocated blocks are unmapped but should treated
1696 * the same as allocated blocks.
1698 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
1702 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
1703 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
1705 if (buffer_unwritten(bh
)) {
1706 /* A delayed write to unwritten bh should be marked
1707 * new and mapped. Mapped ensures that we don't do
1708 * get_block multiple times when we write to the same
1709 * offset and new ensures that we do proper zero out
1710 * for partial write.
1713 set_buffer_mapped(bh
);
1718 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
1724 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
1730 static int __ext4_journalled_writepage(struct page
*page
,
1733 struct address_space
*mapping
= page
->mapping
;
1734 struct inode
*inode
= mapping
->host
;
1735 struct buffer_head
*page_bufs
= NULL
;
1736 handle_t
*handle
= NULL
;
1737 int ret
= 0, err
= 0;
1738 int inline_data
= ext4_has_inline_data(inode
);
1739 struct buffer_head
*inode_bh
= NULL
;
1741 ClearPageChecked(page
);
1744 BUG_ON(page
->index
!= 0);
1745 BUG_ON(len
> ext4_get_max_inline_size(inode
));
1746 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
1747 if (inode_bh
== NULL
)
1750 page_bufs
= page_buffers(page
);
1755 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
1758 /* As soon as we unlock the page, it can go away, but we have
1759 * references to buffers so we are safe */
1762 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
1763 ext4_writepage_trans_blocks(inode
));
1764 if (IS_ERR(handle
)) {
1765 ret
= PTR_ERR(handle
);
1769 BUG_ON(!ext4_handle_valid(handle
));
1772 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
1774 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
1777 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1778 do_journal_get_write_access
);
1780 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
1785 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1786 err
= ext4_journal_stop(handle
);
1790 if (!ext4_has_inline_data(inode
))
1791 ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
,
1793 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1800 * Note that we don't need to start a transaction unless we're journaling data
1801 * because we should have holes filled from ext4_page_mkwrite(). We even don't
1802 * need to file the inode to the transaction's list in ordered mode because if
1803 * we are writing back data added by write(), the inode is already there and if
1804 * we are writing back data modified via mmap(), no one guarantees in which
1805 * transaction the data will hit the disk. In case we are journaling data, we
1806 * cannot start transaction directly because transaction start ranks above page
1807 * lock so we have to do some magic.
1809 * This function can get called via...
1810 * - ext4_writepages after taking page lock (have journal handle)
1811 * - journal_submit_inode_data_buffers (no journal handle)
1812 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
1813 * - grab_page_cache when doing write_begin (have journal handle)
1815 * We don't do any block allocation in this function. If we have page with
1816 * multiple blocks we need to write those buffer_heads that are mapped. This
1817 * is important for mmaped based write. So if we do with blocksize 1K
1818 * truncate(f, 1024);
1819 * a = mmap(f, 0, 4096);
1821 * truncate(f, 4096);
1822 * we have in the page first buffer_head mapped via page_mkwrite call back
1823 * but other buffer_heads would be unmapped but dirty (dirty done via the
1824 * do_wp_page). So writepage should write the first block. If we modify
1825 * the mmap area beyond 1024 we will again get a page_fault and the
1826 * page_mkwrite callback will do the block allocation and mark the
1827 * buffer_heads mapped.
1829 * We redirty the page if we have any buffer_heads that is either delay or
1830 * unwritten in the page.
1832 * We can get recursively called as show below.
1834 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
1837 * But since we don't do any block allocation we should not deadlock.
1838 * Page also have the dirty flag cleared so we don't get recurive page_lock.
1840 static int ext4_writepage(struct page
*page
,
1841 struct writeback_control
*wbc
)
1846 struct buffer_head
*page_bufs
= NULL
;
1847 struct inode
*inode
= page
->mapping
->host
;
1848 struct ext4_io_submit io_submit
;
1850 trace_ext4_writepage(page
);
1851 size
= i_size_read(inode
);
1852 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1853 len
= size
& ~PAGE_CACHE_MASK
;
1855 len
= PAGE_CACHE_SIZE
;
1857 page_bufs
= page_buffers(page
);
1859 * We cannot do block allocation or other extent handling in this
1860 * function. If there are buffers needing that, we have to redirty
1861 * the page. But we may reach here when we do a journal commit via
1862 * journal_submit_inode_data_buffers() and in that case we must write
1863 * allocated buffers to achieve data=ordered mode guarantees.
1865 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
1866 ext4_bh_delay_or_unwritten
)) {
1867 redirty_page_for_writepage(wbc
, page
);
1868 if (current
->flags
& PF_MEMALLOC
) {
1870 * For memory cleaning there's no point in writing only
1871 * some buffers. So just bail out. Warn if we came here
1872 * from direct reclaim.
1874 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
1881 if (PageChecked(page
) && ext4_should_journal_data(inode
))
1883 * It's mmapped pagecache. Add buffers and journal it. There
1884 * doesn't seem much point in redirtying the page here.
1886 return __ext4_journalled_writepage(page
, len
);
1888 ext4_io_submit_init(&io_submit
, wbc
);
1889 io_submit
.io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
1890 if (!io_submit
.io_end
) {
1891 redirty_page_for_writepage(wbc
, page
);
1895 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
);
1896 ext4_io_submit(&io_submit
);
1897 /* Drop io_end reference we got from init */
1898 ext4_put_io_end_defer(io_submit
.io_end
);
1902 static int mpage_submit_page(struct mpage_da_data
*mpd
, struct page
*page
)
1905 loff_t size
= i_size_read(mpd
->inode
);
1908 BUG_ON(page
->index
!= mpd
->first_page
);
1909 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
1910 len
= size
& ~PAGE_CACHE_MASK
;
1912 len
= PAGE_CACHE_SIZE
;
1913 clear_page_dirty_for_io(page
);
1914 err
= ext4_bio_write_page(&mpd
->io_submit
, page
, len
, mpd
->wbc
);
1916 mpd
->wbc
->nr_to_write
--;
1922 #define BH_FLAGS ((1 << BH_Unwritten) | (1 << BH_Delay))
1925 * mballoc gives us at most this number of blocks...
1926 * XXX: That seems to be only a limitation of ext4_mb_normalize_request().
1927 * The rest of mballoc seems to handle chunks up to full group size.
1929 #define MAX_WRITEPAGES_EXTENT_LEN 2048
1932 * mpage_add_bh_to_extent - try to add bh to extent of blocks to map
1934 * @mpd - extent of blocks
1935 * @lblk - logical number of the block in the file
1936 * @bh - buffer head we want to add to the extent
1938 * The function is used to collect contig. blocks in the same state. If the
1939 * buffer doesn't require mapping for writeback and we haven't started the
1940 * extent of buffers to map yet, the function returns 'true' immediately - the
1941 * caller can write the buffer right away. Otherwise the function returns true
1942 * if the block has been added to the extent, false if the block couldn't be
1945 static bool mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, ext4_lblk_t lblk
,
1946 struct buffer_head
*bh
)
1948 struct ext4_map_blocks
*map
= &mpd
->map
;
1950 /* Buffer that doesn't need mapping for writeback? */
1951 if (!buffer_dirty(bh
) || !buffer_mapped(bh
) ||
1952 (!buffer_delay(bh
) && !buffer_unwritten(bh
))) {
1953 /* So far no extent to map => we write the buffer right away */
1954 if (map
->m_len
== 0)
1959 /* First block in the extent? */
1960 if (map
->m_len
== 0) {
1963 map
->m_flags
= bh
->b_state
& BH_FLAGS
;
1967 /* Don't go larger than mballoc is willing to allocate */
1968 if (map
->m_len
>= MAX_WRITEPAGES_EXTENT_LEN
)
1971 /* Can we merge the block to our big extent? */
1972 if (lblk
== map
->m_lblk
+ map
->m_len
&&
1973 (bh
->b_state
& BH_FLAGS
) == map
->m_flags
) {
1981 * mpage_process_page_bufs - submit page buffers for IO or add them to extent
1983 * @mpd - extent of blocks for mapping
1984 * @head - the first buffer in the page
1985 * @bh - buffer we should start processing from
1986 * @lblk - logical number of the block in the file corresponding to @bh
1988 * Walk through page buffers from @bh upto @head (exclusive) and either submit
1989 * the page for IO if all buffers in this page were mapped and there's no
1990 * accumulated extent of buffers to map or add buffers in the page to the
1991 * extent of buffers to map. The function returns 1 if the caller can continue
1992 * by processing the next page, 0 if it should stop adding buffers to the
1993 * extent to map because we cannot extend it anymore. It can also return value
1994 * < 0 in case of error during IO submission.
1996 static int mpage_process_page_bufs(struct mpage_da_data
*mpd
,
1997 struct buffer_head
*head
,
1998 struct buffer_head
*bh
,
2001 struct inode
*inode
= mpd
->inode
;
2003 ext4_lblk_t blocks
= (i_size_read(inode
) + (1 << inode
->i_blkbits
) - 1)
2004 >> inode
->i_blkbits
;
2007 BUG_ON(buffer_locked(bh
));
2009 if (lblk
>= blocks
|| !mpage_add_bh_to_extent(mpd
, lblk
, bh
)) {
2010 /* Found extent to map? */
2013 /* Everything mapped so far and we hit EOF */
2016 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
2017 /* So far everything mapped? Submit the page for IO. */
2018 if (mpd
->map
.m_len
== 0) {
2019 err
= mpage_submit_page(mpd
, head
->b_page
);
2023 return lblk
< blocks
;
2027 * mpage_map_buffers - update buffers corresponding to changed extent and
2028 * submit fully mapped pages for IO
2030 * @mpd - description of extent to map, on return next extent to map
2032 * Scan buffers corresponding to changed extent (we expect corresponding pages
2033 * to be already locked) and update buffer state according to new extent state.
2034 * We map delalloc buffers to their physical location, clear unwritten bits,
2035 * and mark buffers as uninit when we perform writes to uninitialized extents
2036 * and do extent conversion after IO is finished. If the last page is not fully
2037 * mapped, we update @map to the next extent in the last page that needs
2038 * mapping. Otherwise we submit the page for IO.
2040 static int mpage_map_and_submit_buffers(struct mpage_da_data
*mpd
)
2042 struct pagevec pvec
;
2044 struct inode
*inode
= mpd
->inode
;
2045 struct buffer_head
*head
, *bh
;
2046 int bpp_bits
= PAGE_CACHE_SHIFT
- inode
->i_blkbits
;
2052 start
= mpd
->map
.m_lblk
>> bpp_bits
;
2053 end
= (mpd
->map
.m_lblk
+ mpd
->map
.m_len
- 1) >> bpp_bits
;
2054 lblk
= start
<< bpp_bits
;
2055 pblock
= mpd
->map
.m_pblk
;
2057 pagevec_init(&pvec
, 0);
2058 while (start
<= end
) {
2059 nr_pages
= pagevec_lookup(&pvec
, inode
->i_mapping
, start
,
2063 for (i
= 0; i
< nr_pages
; i
++) {
2064 struct page
*page
= pvec
.pages
[i
];
2066 if (page
->index
> end
)
2068 /* Up to 'end' pages must be contiguous */
2069 BUG_ON(page
->index
!= start
);
2070 bh
= head
= page_buffers(page
);
2072 if (lblk
< mpd
->map
.m_lblk
)
2074 if (lblk
>= mpd
->map
.m_lblk
+ mpd
->map
.m_len
) {
2076 * Buffer after end of mapped extent.
2077 * Find next buffer in the page to map.
2080 mpd
->map
.m_flags
= 0;
2082 * FIXME: If dioread_nolock supports
2083 * blocksize < pagesize, we need to make
2084 * sure we add size mapped so far to
2085 * io_end->size as the following call
2086 * can submit the page for IO.
2088 err
= mpage_process_page_bufs(mpd
, head
,
2090 pagevec_release(&pvec
);
2095 if (buffer_delay(bh
)) {
2096 clear_buffer_delay(bh
);
2097 bh
->b_blocknr
= pblock
++;
2099 clear_buffer_unwritten(bh
);
2100 } while (lblk
++, (bh
= bh
->b_this_page
) != head
);
2103 * FIXME: This is going to break if dioread_nolock
2104 * supports blocksize < pagesize as we will try to
2105 * convert potentially unmapped parts of inode.
2107 mpd
->io_submit
.io_end
->size
+= PAGE_CACHE_SIZE
;
2108 /* Page fully mapped - let IO run! */
2109 err
= mpage_submit_page(mpd
, page
);
2111 pagevec_release(&pvec
);
2116 pagevec_release(&pvec
);
2118 /* Extent fully mapped and matches with page boundary. We are done. */
2120 mpd
->map
.m_flags
= 0;
2124 static int mpage_map_one_extent(handle_t
*handle
, struct mpage_da_data
*mpd
)
2126 struct inode
*inode
= mpd
->inode
;
2127 struct ext4_map_blocks
*map
= &mpd
->map
;
2128 int get_blocks_flags
;
2131 trace_ext4_da_write_pages_extent(inode
, map
);
2133 * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
2134 * to convert an uninitialized extent to be initialized (in the case
2135 * where we have written into one or more preallocated blocks). It is
2136 * possible that we're going to need more metadata blocks than
2137 * previously reserved. However we must not fail because we're in
2138 * writeback and there is nothing we can do about it so it might result
2139 * in data loss. So use reserved blocks to allocate metadata if
2142 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if the blocks
2143 * in question are delalloc blocks. This affects functions in many
2144 * different parts of the allocation call path. This flag exists
2145 * primarily because we don't want to change *many* call functions, so
2146 * ext4_map_blocks() will set the EXT4_STATE_DELALLOC_RESERVED flag
2147 * once the inode's allocation semaphore is taken.
2149 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
2150 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
2151 if (ext4_should_dioread_nolock(inode
))
2152 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
2153 if (map
->m_flags
& (1 << BH_Delay
))
2154 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
2156 err
= ext4_map_blocks(handle
, inode
, map
, get_blocks_flags
);
2159 if (map
->m_flags
& EXT4_MAP_UNINIT
) {
2160 if (!mpd
->io_submit
.io_end
->handle
&&
2161 ext4_handle_valid(handle
)) {
2162 mpd
->io_submit
.io_end
->handle
= handle
->h_rsv_handle
;
2163 handle
->h_rsv_handle
= NULL
;
2165 ext4_set_io_unwritten_flag(inode
, mpd
->io_submit
.io_end
);
2168 BUG_ON(map
->m_len
== 0);
2169 if (map
->m_flags
& EXT4_MAP_NEW
) {
2170 struct block_device
*bdev
= inode
->i_sb
->s_bdev
;
2173 for (i
= 0; i
< map
->m_len
; i
++)
2174 unmap_underlying_metadata(bdev
, map
->m_pblk
+ i
);
2180 * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
2181 * mpd->len and submit pages underlying it for IO
2183 * @handle - handle for journal operations
2184 * @mpd - extent to map
2185 * @give_up_on_write - we set this to true iff there is a fatal error and there
2186 * is no hope of writing the data. The caller should discard
2187 * dirty pages to avoid infinite loops.
2189 * The function maps extent starting at mpd->lblk of length mpd->len. If it is
2190 * delayed, blocks are allocated, if it is unwritten, we may need to convert
2191 * them to initialized or split the described range from larger unwritten
2192 * extent. Note that we need not map all the described range since allocation
2193 * can return less blocks or the range is covered by more unwritten extents. We
2194 * cannot map more because we are limited by reserved transaction credits. On
2195 * the other hand we always make sure that the last touched page is fully
2196 * mapped so that it can be written out (and thus forward progress is
2197 * guaranteed). After mapping we submit all mapped pages for IO.
2199 static int mpage_map_and_submit_extent(handle_t
*handle
,
2200 struct mpage_da_data
*mpd
,
2201 bool *give_up_on_write
)
2203 struct inode
*inode
= mpd
->inode
;
2204 struct ext4_map_blocks
*map
= &mpd
->map
;
2208 mpd
->io_submit
.io_end
->offset
=
2209 ((loff_t
)map
->m_lblk
) << inode
->i_blkbits
;
2211 err
= mpage_map_one_extent(handle
, mpd
);
2213 struct super_block
*sb
= inode
->i_sb
;
2215 if (EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)
2216 goto invalidate_dirty_pages
;
2218 * Let the uper layers retry transient errors.
2219 * In the case of ENOSPC, if ext4_count_free_blocks()
2220 * is non-zero, a commit should free up blocks.
2222 if ((err
== -ENOMEM
) ||
2223 (err
== -ENOSPC
&& ext4_count_free_clusters(sb
)))
2225 ext4_msg(sb
, KERN_CRIT
,
2226 "Delayed block allocation failed for "
2227 "inode %lu at logical offset %llu with"
2228 " max blocks %u with error %d",
2230 (unsigned long long)map
->m_lblk
,
2231 (unsigned)map
->m_len
, -err
);
2232 ext4_msg(sb
, KERN_CRIT
,
2233 "This should not happen!! Data will "
2236 ext4_print_free_blocks(inode
);
2237 invalidate_dirty_pages
:
2238 *give_up_on_write
= true;
2242 * Update buffer state, submit mapped pages, and get us new
2245 err
= mpage_map_and_submit_buffers(mpd
);
2248 } while (map
->m_len
);
2251 * Update on-disk size after IO is submitted. Races with
2252 * truncate are avoided by checking i_size under i_data_sem.
2254 disksize
= ((loff_t
)mpd
->first_page
) << PAGE_CACHE_SHIFT
;
2255 if (disksize
> EXT4_I(inode
)->i_disksize
) {
2259 down_write(&EXT4_I(inode
)->i_data_sem
);
2260 i_size
= i_size_read(inode
);
2261 if (disksize
> i_size
)
2263 if (disksize
> EXT4_I(inode
)->i_disksize
)
2264 EXT4_I(inode
)->i_disksize
= disksize
;
2265 err2
= ext4_mark_inode_dirty(handle
, inode
);
2266 up_write(&EXT4_I(inode
)->i_data_sem
);
2268 ext4_error(inode
->i_sb
,
2269 "Failed to mark inode %lu dirty",
2278 * Calculate the total number of credits to reserve for one writepages
2279 * iteration. This is called from ext4_writepages(). We map an extent of
2280 * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
2281 * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
2282 * bpp - 1 blocks in bpp different extents.
2284 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2286 int bpp
= ext4_journal_blocks_per_page(inode
);
2288 return ext4_meta_trans_blocks(inode
,
2289 MAX_WRITEPAGES_EXTENT_LEN
+ bpp
- 1, bpp
);
2293 * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
2294 * and underlying extent to map
2296 * @mpd - where to look for pages
2298 * Walk dirty pages in the mapping. If they are fully mapped, submit them for
2299 * IO immediately. When we find a page which isn't mapped we start accumulating
2300 * extent of buffers underlying these pages that needs mapping (formed by
2301 * either delayed or unwritten buffers). We also lock the pages containing
2302 * these buffers. The extent found is returned in @mpd structure (starting at
2303 * mpd->lblk with length mpd->len blocks).
2305 * Note that this function can attach bios to one io_end structure which are
2306 * neither logically nor physically contiguous. Although it may seem as an
2307 * unnecessary complication, it is actually inevitable in blocksize < pagesize
2308 * case as we need to track IO to all buffers underlying a page in one io_end.
2310 static int mpage_prepare_extent_to_map(struct mpage_da_data
*mpd
)
2312 struct address_space
*mapping
= mpd
->inode
->i_mapping
;
2313 struct pagevec pvec
;
2314 unsigned int nr_pages
;
2315 long left
= mpd
->wbc
->nr_to_write
;
2316 pgoff_t index
= mpd
->first_page
;
2317 pgoff_t end
= mpd
->last_page
;
2320 int blkbits
= mpd
->inode
->i_blkbits
;
2322 struct buffer_head
*head
;
2324 if (mpd
->wbc
->sync_mode
== WB_SYNC_ALL
|| mpd
->wbc
->tagged_writepages
)
2325 tag
= PAGECACHE_TAG_TOWRITE
;
2327 tag
= PAGECACHE_TAG_DIRTY
;
2329 pagevec_init(&pvec
, 0);
2331 mpd
->next_page
= index
;
2332 while (index
<= end
) {
2333 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2334 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2338 for (i
= 0; i
< nr_pages
; i
++) {
2339 struct page
*page
= pvec
.pages
[i
];
2342 * At this point, the page may be truncated or
2343 * invalidated (changing page->mapping to NULL), or
2344 * even swizzled back from swapper_space to tmpfs file
2345 * mapping. However, page->index will not change
2346 * because we have a reference on the page.
2348 if (page
->index
> end
)
2352 * Accumulated enough dirty pages? This doesn't apply
2353 * to WB_SYNC_ALL mode. For integrity sync we have to
2354 * keep going because someone may be concurrently
2355 * dirtying pages, and we might have synced a lot of
2356 * newly appeared dirty pages, but have not synced all
2357 * of the old dirty pages.
2359 if (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
&& left
<= 0)
2362 /* If we can't merge this page, we are done. */
2363 if (mpd
->map
.m_len
> 0 && mpd
->next_page
!= page
->index
)
2368 * If the page is no longer dirty, or its mapping no
2369 * longer corresponds to inode we are writing (which
2370 * means it has been truncated or invalidated), or the
2371 * page is already under writeback and we are not doing
2372 * a data integrity writeback, skip the page
2374 if (!PageDirty(page
) ||
2375 (PageWriteback(page
) &&
2376 (mpd
->wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2377 unlikely(page
->mapping
!= mapping
)) {
2382 wait_on_page_writeback(page
);
2383 BUG_ON(PageWriteback(page
));
2385 if (mpd
->map
.m_len
== 0)
2386 mpd
->first_page
= page
->index
;
2387 mpd
->next_page
= page
->index
+ 1;
2388 /* Add all dirty buffers to mpd */
2389 lblk
= ((ext4_lblk_t
)page
->index
) <<
2390 (PAGE_CACHE_SHIFT
- blkbits
);
2391 head
= page_buffers(page
);
2392 err
= mpage_process_page_bufs(mpd
, head
, head
, lblk
);
2398 pagevec_release(&pvec
);
2403 pagevec_release(&pvec
);
2407 static int __writepage(struct page
*page
, struct writeback_control
*wbc
,
2410 struct address_space
*mapping
= data
;
2411 int ret
= ext4_writepage(page
, wbc
);
2412 mapping_set_error(mapping
, ret
);
2416 static int ext4_writepages(struct address_space
*mapping
,
2417 struct writeback_control
*wbc
)
2419 pgoff_t writeback_index
= 0;
2420 long nr_to_write
= wbc
->nr_to_write
;
2421 int range_whole
= 0;
2423 handle_t
*handle
= NULL
;
2424 struct mpage_da_data mpd
;
2425 struct inode
*inode
= mapping
->host
;
2426 int needed_blocks
, rsv_blocks
= 0, ret
= 0;
2427 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2429 struct blk_plug plug
;
2430 bool give_up_on_write
= false;
2432 trace_ext4_writepages(inode
, wbc
);
2435 * No pages to write? This is mainly a kludge to avoid starting
2436 * a transaction for special inodes like journal inode on last iput()
2437 * because that could violate lock ordering on umount
2439 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2440 goto out_writepages
;
2442 if (ext4_should_journal_data(inode
)) {
2443 struct blk_plug plug
;
2445 blk_start_plug(&plug
);
2446 ret
= write_cache_pages(mapping
, wbc
, __writepage
, mapping
);
2447 blk_finish_plug(&plug
);
2448 goto out_writepages
;
2452 * If the filesystem has aborted, it is read-only, so return
2453 * right away instead of dumping stack traces later on that
2454 * will obscure the real source of the problem. We test
2455 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2456 * the latter could be true if the filesystem is mounted
2457 * read-only, and in that case, ext4_writepages should
2458 * *never* be called, so if that ever happens, we would want
2461 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
2463 goto out_writepages
;
2466 if (ext4_should_dioread_nolock(inode
)) {
2468 * We may need to convert up to one extent per block in
2469 * the page and we may dirty the inode.
2471 rsv_blocks
= 1 + (PAGE_CACHE_SIZE
>> inode
->i_blkbits
);
2475 * If we have inline data and arrive here, it means that
2476 * we will soon create the block for the 1st page, so
2477 * we'd better clear the inline data here.
2479 if (ext4_has_inline_data(inode
)) {
2480 /* Just inode will be modified... */
2481 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
2482 if (IS_ERR(handle
)) {
2483 ret
= PTR_ERR(handle
);
2484 goto out_writepages
;
2486 BUG_ON(ext4_test_inode_state(inode
,
2487 EXT4_STATE_MAY_INLINE_DATA
));
2488 ext4_destroy_inline_data(handle
, inode
);
2489 ext4_journal_stop(handle
);
2492 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2495 if (wbc
->range_cyclic
) {
2496 writeback_index
= mapping
->writeback_index
;
2497 if (writeback_index
)
2499 mpd
.first_page
= writeback_index
;
2502 mpd
.first_page
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2503 mpd
.last_page
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2508 ext4_io_submit_init(&mpd
.io_submit
, wbc
);
2510 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2511 tag_pages_for_writeback(mapping
, mpd
.first_page
, mpd
.last_page
);
2513 blk_start_plug(&plug
);
2514 while (!done
&& mpd
.first_page
<= mpd
.last_page
) {
2515 /* For each extent of pages we use new io_end */
2516 mpd
.io_submit
.io_end
= ext4_init_io_end(inode
, GFP_KERNEL
);
2517 if (!mpd
.io_submit
.io_end
) {
2523 * We have two constraints: We find one extent to map and we
2524 * must always write out whole page (makes a difference when
2525 * blocksize < pagesize) so that we don't block on IO when we
2526 * try to write out the rest of the page. Journalled mode is
2527 * not supported by delalloc.
2529 BUG_ON(ext4_should_journal_data(inode
));
2530 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2532 /* start a new transaction */
2533 handle
= ext4_journal_start_with_reserve(inode
,
2534 EXT4_HT_WRITE_PAGE
, needed_blocks
, rsv_blocks
);
2535 if (IS_ERR(handle
)) {
2536 ret
= PTR_ERR(handle
);
2537 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2538 "%ld pages, ino %lu; err %d", __func__
,
2539 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2540 /* Release allocated io_end */
2541 ext4_put_io_end(mpd
.io_submit
.io_end
);
2545 trace_ext4_da_write_pages(inode
, mpd
.first_page
, mpd
.wbc
);
2546 ret
= mpage_prepare_extent_to_map(&mpd
);
2549 ret
= mpage_map_and_submit_extent(handle
, &mpd
,
2553 * We scanned the whole range (or exhausted
2554 * nr_to_write), submitted what was mapped and
2555 * didn't find anything needing mapping. We are
2561 ext4_journal_stop(handle
);
2562 /* Submit prepared bio */
2563 ext4_io_submit(&mpd
.io_submit
);
2564 /* Unlock pages we didn't use */
2565 mpage_release_unused_pages(&mpd
, give_up_on_write
);
2566 /* Drop our io_end reference we got from init */
2567 ext4_put_io_end(mpd
.io_submit
.io_end
);
2569 if (ret
== -ENOSPC
&& sbi
->s_journal
) {
2571 * Commit the transaction which would
2572 * free blocks released in the transaction
2575 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2579 /* Fatal error - ENOMEM, EIO... */
2583 blk_finish_plug(&plug
);
2584 if (!ret
&& !cycled
&& wbc
->nr_to_write
> 0) {
2586 mpd
.last_page
= writeback_index
- 1;
2592 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2594 * Set the writeback_index so that range_cyclic
2595 * mode will write it back later
2597 mapping
->writeback_index
= mpd
.first_page
;
2600 trace_ext4_writepages_result(inode
, wbc
, ret
,
2601 nr_to_write
- wbc
->nr_to_write
);
2605 static int ext4_nonda_switch(struct super_block
*sb
)
2607 s64 free_clusters
, dirty_clusters
;
2608 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2611 * switch to non delalloc mode if we are running low
2612 * on free block. The free block accounting via percpu
2613 * counters can get slightly wrong with percpu_counter_batch getting
2614 * accumulated on each CPU without updating global counters
2615 * Delalloc need an accurate free block accounting. So switch
2616 * to non delalloc when we are near to error range.
2619 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2621 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2623 * Start pushing delalloc when 1/2 of free blocks are dirty.
2625 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2626 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2628 if (2 * free_clusters
< 3 * dirty_clusters
||
2629 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2631 * free block count is less than 150% of dirty blocks
2632 * or free blocks is less than watermark
2639 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2640 loff_t pos
, unsigned len
, unsigned flags
,
2641 struct page
**pagep
, void **fsdata
)
2643 int ret
, retries
= 0;
2646 struct inode
*inode
= mapping
->host
;
2649 index
= pos
>> PAGE_CACHE_SHIFT
;
2651 if (ext4_nonda_switch(inode
->i_sb
)) {
2652 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2653 return ext4_write_begin(file
, mapping
, pos
,
2654 len
, flags
, pagep
, fsdata
);
2656 *fsdata
= (void *)0;
2657 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2659 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2660 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2670 * grab_cache_page_write_begin() can take a long time if the
2671 * system is thrashing due to memory pressure, or if the page
2672 * is being written back. So grab it first before we start
2673 * the transaction handle. This also allows us to allocate
2674 * the page (if needed) without using GFP_NOFS.
2677 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2683 * With delayed allocation, we don't log the i_disksize update
2684 * if there is delayed block allocation. But we still need
2685 * to journalling the i_disksize update if writes to the end
2686 * of file which has an already mapped buffer.
2689 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, 1);
2690 if (IS_ERR(handle
)) {
2691 page_cache_release(page
);
2692 return PTR_ERR(handle
);
2696 if (page
->mapping
!= mapping
) {
2697 /* The page got truncated from under us */
2699 page_cache_release(page
);
2700 ext4_journal_stop(handle
);
2703 /* In case writeback began while the page was unlocked */
2704 wait_for_stable_page(page
);
2706 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2709 ext4_journal_stop(handle
);
2711 * block_write_begin may have instantiated a few blocks
2712 * outside i_size. Trim these off again. Don't need
2713 * i_size_read because we hold i_mutex.
2715 if (pos
+ len
> inode
->i_size
)
2716 ext4_truncate_failed_write(inode
);
2718 if (ret
== -ENOSPC
&&
2719 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2722 page_cache_release(page
);
2731 * Check if we should update i_disksize
2732 * when write to the end of file but not require block allocation
2734 static int ext4_da_should_update_i_disksize(struct page
*page
,
2735 unsigned long offset
)
2737 struct buffer_head
*bh
;
2738 struct inode
*inode
= page
->mapping
->host
;
2742 bh
= page_buffers(page
);
2743 idx
= offset
>> inode
->i_blkbits
;
2745 for (i
= 0; i
< idx
; i
++)
2746 bh
= bh
->b_this_page
;
2748 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2753 static int ext4_da_write_end(struct file
*file
,
2754 struct address_space
*mapping
,
2755 loff_t pos
, unsigned len
, unsigned copied
,
2756 struct page
*page
, void *fsdata
)
2758 struct inode
*inode
= mapping
->host
;
2760 handle_t
*handle
= ext4_journal_current_handle();
2762 unsigned long start
, end
;
2763 int write_mode
= (int)(unsigned long)fsdata
;
2765 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2766 return ext4_write_end(file
, mapping
, pos
,
2767 len
, copied
, page
, fsdata
);
2769 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2770 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2771 end
= start
+ copied
- 1;
2774 * generic_write_end() will run mark_inode_dirty() if i_size
2775 * changes. So let's piggyback the i_disksize mark_inode_dirty
2778 new_i_size
= pos
+ copied
;
2779 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2780 if (ext4_has_inline_data(inode
) ||
2781 ext4_da_should_update_i_disksize(page
, end
)) {
2782 down_write(&EXT4_I(inode
)->i_data_sem
);
2783 if (new_i_size
> EXT4_I(inode
)->i_disksize
)
2784 EXT4_I(inode
)->i_disksize
= new_i_size
;
2785 up_write(&EXT4_I(inode
)->i_data_sem
);
2786 /* We need to mark inode dirty even if
2787 * new_i_size is less that inode->i_size
2788 * bu greater than i_disksize.(hint delalloc)
2790 ext4_mark_inode_dirty(handle
, inode
);
2794 if (write_mode
!= CONVERT_INLINE_DATA
&&
2795 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2796 ext4_has_inline_data(inode
))
2797 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2800 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2806 ret2
= ext4_journal_stop(handle
);
2810 return ret
? ret
: copied
;
2813 static void ext4_da_invalidatepage(struct page
*page
, unsigned int offset
,
2814 unsigned int length
)
2817 * Drop reserved blocks
2819 BUG_ON(!PageLocked(page
));
2820 if (!page_has_buffers(page
))
2823 ext4_da_page_release_reservation(page
, offset
, length
);
2826 ext4_invalidatepage(page
, offset
, length
);
2832 * Force all delayed allocation blocks to be allocated for a given inode.
2834 int ext4_alloc_da_blocks(struct inode
*inode
)
2836 trace_ext4_alloc_da_blocks(inode
);
2838 if (!EXT4_I(inode
)->i_reserved_data_blocks
&&
2839 !EXT4_I(inode
)->i_reserved_meta_blocks
)
2843 * We do something simple for now. The filemap_flush() will
2844 * also start triggering a write of the data blocks, which is
2845 * not strictly speaking necessary (and for users of
2846 * laptop_mode, not even desirable). However, to do otherwise
2847 * would require replicating code paths in:
2849 * ext4_writepages() ->
2850 * write_cache_pages() ---> (via passed in callback function)
2851 * __mpage_da_writepage() -->
2852 * mpage_add_bh_to_extent()
2853 * mpage_da_map_blocks()
2855 * The problem is that write_cache_pages(), located in
2856 * mm/page-writeback.c, marks pages clean in preparation for
2857 * doing I/O, which is not desirable if we're not planning on
2860 * We could call write_cache_pages(), and then redirty all of
2861 * the pages by calling redirty_page_for_writepage() but that
2862 * would be ugly in the extreme. So instead we would need to
2863 * replicate parts of the code in the above functions,
2864 * simplifying them because we wouldn't actually intend to
2865 * write out the pages, but rather only collect contiguous
2866 * logical block extents, call the multi-block allocator, and
2867 * then update the buffer heads with the block allocations.
2869 * For now, though, we'll cheat by calling filemap_flush(),
2870 * which will map the blocks, and start the I/O, but not
2871 * actually wait for the I/O to complete.
2873 return filemap_flush(inode
->i_mapping
);
2877 * bmap() is special. It gets used by applications such as lilo and by
2878 * the swapper to find the on-disk block of a specific piece of data.
2880 * Naturally, this is dangerous if the block concerned is still in the
2881 * journal. If somebody makes a swapfile on an ext4 data-journaling
2882 * filesystem and enables swap, then they may get a nasty shock when the
2883 * data getting swapped to that swapfile suddenly gets overwritten by
2884 * the original zero's written out previously to the journal and
2885 * awaiting writeback in the kernel's buffer cache.
2887 * So, if we see any bmap calls here on a modified, data-journaled file,
2888 * take extra steps to flush any blocks which might be in the cache.
2890 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2892 struct inode
*inode
= mapping
->host
;
2897 * We can get here for an inline file via the FIBMAP ioctl
2899 if (ext4_has_inline_data(inode
))
2902 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2903 test_opt(inode
->i_sb
, DELALLOC
)) {
2905 * With delalloc we want to sync the file
2906 * so that we can make sure we allocate
2909 filemap_write_and_wait(mapping
);
2912 if (EXT4_JOURNAL(inode
) &&
2913 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2915 * This is a REALLY heavyweight approach, but the use of
2916 * bmap on dirty files is expected to be extremely rare:
2917 * only if we run lilo or swapon on a freshly made file
2918 * do we expect this to happen.
2920 * (bmap requires CAP_SYS_RAWIO so this does not
2921 * represent an unprivileged user DOS attack --- we'd be
2922 * in trouble if mortal users could trigger this path at
2925 * NB. EXT4_STATE_JDATA is not set on files other than
2926 * regular files. If somebody wants to bmap a directory
2927 * or symlink and gets confused because the buffer
2928 * hasn't yet been flushed to disk, they deserve
2929 * everything they get.
2932 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2933 journal
= EXT4_JOURNAL(inode
);
2934 jbd2_journal_lock_updates(journal
);
2935 err
= jbd2_journal_flush(journal
);
2936 jbd2_journal_unlock_updates(journal
);
2942 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2945 static int ext4_readpage(struct file
*file
, struct page
*page
)
2948 struct inode
*inode
= page
->mapping
->host
;
2950 trace_ext4_readpage(page
);
2952 if (ext4_has_inline_data(inode
))
2953 ret
= ext4_readpage_inline(inode
, page
);
2956 return mpage_readpage(page
, ext4_get_block
);
2962 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2963 struct list_head
*pages
, unsigned nr_pages
)
2965 struct inode
*inode
= mapping
->host
;
2967 /* If the file has inline data, no need to do readpages. */
2968 if (ext4_has_inline_data(inode
))
2971 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
2974 static void ext4_invalidatepage(struct page
*page
, unsigned int offset
,
2975 unsigned int length
)
2977 trace_ext4_invalidatepage(page
, offset
, length
);
2979 /* No journalling happens on data buffers when this function is used */
2980 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
2982 block_invalidatepage(page
, offset
, length
);
2985 static int __ext4_journalled_invalidatepage(struct page
*page
,
2986 unsigned int offset
,
2987 unsigned int length
)
2989 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2991 trace_ext4_journalled_invalidatepage(page
, offset
, length
);
2994 * If it's a full truncate we just forget about the pending dirtying
2996 if (offset
== 0 && length
== PAGE_CACHE_SIZE
)
2997 ClearPageChecked(page
);
2999 return jbd2_journal_invalidatepage(journal
, page
, offset
, length
);
3002 /* Wrapper for aops... */
3003 static void ext4_journalled_invalidatepage(struct page
*page
,
3004 unsigned int offset
,
3005 unsigned int length
)
3007 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
, length
) < 0);
3010 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
3012 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
3014 trace_ext4_releasepage(page
);
3016 /* Page has dirty journalled data -> cannot release */
3017 if (PageChecked(page
))
3020 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
3022 return try_to_free_buffers(page
);
3026 * ext4_get_block used when preparing for a DIO write or buffer write.
3027 * We allocate an uinitialized extent if blocks haven't been allocated.
3028 * The extent will be converted to initialized after the IO is complete.
3030 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
3031 struct buffer_head
*bh_result
, int create
)
3033 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
3034 inode
->i_ino
, create
);
3035 return _ext4_get_block(inode
, iblock
, bh_result
,
3036 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
3039 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
3040 struct buffer_head
*bh_result
, int create
)
3042 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
3043 inode
->i_ino
, create
);
3044 return _ext4_get_block(inode
, iblock
, bh_result
,
3045 EXT4_GET_BLOCKS_NO_LOCK
);
3048 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
3049 ssize_t size
, void *private)
3051 ext4_io_end_t
*io_end
= iocb
->private;
3053 /* if not async direct IO just return */
3057 ext_debug("ext4_end_io_dio(): io_end 0x%p "
3058 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
3059 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
3062 iocb
->private = NULL
;
3063 io_end
->offset
= offset
;
3064 io_end
->size
= size
;
3065 ext4_put_io_end(io_end
);
3069 * For ext4 extent files, ext4 will do direct-io write to holes,
3070 * preallocated extents, and those write extend the file, no need to
3071 * fall back to buffered IO.
3073 * For holes, we fallocate those blocks, mark them as uninitialized
3074 * If those blocks were preallocated, we mark sure they are split, but
3075 * still keep the range to write as uninitialized.
3077 * The unwritten extents will be converted to written when DIO is completed.
3078 * For async direct IO, since the IO may still pending when return, we
3079 * set up an end_io call back function, which will do the conversion
3080 * when async direct IO completed.
3082 * If the O_DIRECT write will extend the file then add this inode to the
3083 * orphan list. So recovery will truncate it back to the original size
3084 * if the machine crashes during the write.
3087 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
3088 const struct iovec
*iov
, loff_t offset
,
3089 unsigned long nr_segs
)
3091 struct file
*file
= iocb
->ki_filp
;
3092 struct inode
*inode
= file
->f_mapping
->host
;
3094 size_t count
= iov_length(iov
, nr_segs
);
3096 get_block_t
*get_block_func
= NULL
;
3098 loff_t final_size
= offset
+ count
;
3099 ext4_io_end_t
*io_end
= NULL
;
3101 /* Use the old path for reads and writes beyond i_size. */
3102 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
3103 return ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3105 BUG_ON(iocb
->private == NULL
);
3108 * Make all waiters for direct IO properly wait also for extent
3109 * conversion. This also disallows race between truncate() and
3110 * overwrite DIO as i_dio_count needs to be incremented under i_mutex.
3113 atomic_inc(&inode
->i_dio_count
);
3115 /* If we do a overwrite dio, i_mutex locking can be released */
3116 overwrite
= *((int *)iocb
->private);
3119 down_read(&EXT4_I(inode
)->i_data_sem
);
3120 mutex_unlock(&inode
->i_mutex
);
3124 * We could direct write to holes and fallocate.
3126 * Allocated blocks to fill the hole are marked as
3127 * uninitialized to prevent parallel buffered read to expose
3128 * the stale data before DIO complete the data IO.
3130 * As to previously fallocated extents, ext4 get_block will
3131 * just simply mark the buffer mapped but still keep the
3132 * extents uninitialized.
3134 * For non AIO case, we will convert those unwritten extents
3135 * to written after return back from blockdev_direct_IO.
3137 * For async DIO, the conversion needs to be deferred when the
3138 * IO is completed. The ext4 end_io callback function will be
3139 * called to take care of the conversion work. Here for async
3140 * case, we allocate an io_end structure to hook to the iocb.
3142 iocb
->private = NULL
;
3143 ext4_inode_aio_set(inode
, NULL
);
3144 if (!is_sync_kiocb(iocb
)) {
3145 io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3151 * Grab reference for DIO. Will be dropped in ext4_end_io_dio()
3153 iocb
->private = ext4_get_io_end(io_end
);
3155 * we save the io structure for current async direct
3156 * IO, so that later ext4_map_blocks() could flag the
3157 * io structure whether there is a unwritten extents
3158 * needs to be converted when IO is completed.
3160 ext4_inode_aio_set(inode
, io_end
);
3164 get_block_func
= ext4_get_block_write_nolock
;
3166 get_block_func
= ext4_get_block_write
;
3167 dio_flags
= DIO_LOCKING
;
3169 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3170 inode
->i_sb
->s_bdev
, iov
,
3178 * Put our reference to io_end. This can free the io_end structure e.g.
3179 * in sync IO case or in case of error. It can even perform extent
3180 * conversion if all bios we submitted finished before we got here.
3181 * Note that in that case iocb->private can be already set to NULL
3185 ext4_inode_aio_set(inode
, NULL
);
3186 ext4_put_io_end(io_end
);
3188 * When no IO was submitted ext4_end_io_dio() was not
3189 * called so we have to put iocb's reference.
3191 if (ret
<= 0 && ret
!= -EIOCBQUEUED
&& iocb
->private) {
3192 WARN_ON(iocb
->private != io_end
);
3193 WARN_ON(io_end
->flag
& EXT4_IO_END_UNWRITTEN
);
3194 ext4_put_io_end(io_end
);
3195 iocb
->private = NULL
;
3198 if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3199 EXT4_STATE_DIO_UNWRITTEN
)) {
3202 * for non AIO case, since the IO is already
3203 * completed, we could do the conversion right here
3205 err
= ext4_convert_unwritten_extents(NULL
, inode
,
3209 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3214 inode_dio_done(inode
);
3215 /* take i_mutex locking again if we do a ovewrite dio */
3217 up_read(&EXT4_I(inode
)->i_data_sem
);
3218 mutex_lock(&inode
->i_mutex
);
3224 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3225 const struct iovec
*iov
, loff_t offset
,
3226 unsigned long nr_segs
)
3228 struct file
*file
= iocb
->ki_filp
;
3229 struct inode
*inode
= file
->f_mapping
->host
;
3233 * If we are doing data journalling we don't support O_DIRECT
3235 if (ext4_should_journal_data(inode
))
3238 /* Let buffer I/O handle the inline data case. */
3239 if (ext4_has_inline_data(inode
))
3242 trace_ext4_direct_IO_enter(inode
, offset
, iov_length(iov
, nr_segs
), rw
);
3243 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3244 ret
= ext4_ext_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3246 ret
= ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3247 trace_ext4_direct_IO_exit(inode
, offset
,
3248 iov_length(iov
, nr_segs
), rw
, ret
);
3253 * Pages can be marked dirty completely asynchronously from ext4's journalling
3254 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3255 * much here because ->set_page_dirty is called under VFS locks. The page is
3256 * not necessarily locked.
3258 * We cannot just dirty the page and leave attached buffers clean, because the
3259 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3260 * or jbddirty because all the journalling code will explode.
3262 * So what we do is to mark the page "pending dirty" and next time writepage
3263 * is called, propagate that into the buffers appropriately.
3265 static int ext4_journalled_set_page_dirty(struct page
*page
)
3267 SetPageChecked(page
);
3268 return __set_page_dirty_nobuffers(page
);
3271 static const struct address_space_operations ext4_aops
= {
3272 .readpage
= ext4_readpage
,
3273 .readpages
= ext4_readpages
,
3274 .writepage
= ext4_writepage
,
3275 .writepages
= ext4_writepages
,
3276 .write_begin
= ext4_write_begin
,
3277 .write_end
= ext4_write_end
,
3279 .invalidatepage
= ext4_invalidatepage
,
3280 .releasepage
= ext4_releasepage
,
3281 .direct_IO
= ext4_direct_IO
,
3282 .migratepage
= buffer_migrate_page
,
3283 .is_partially_uptodate
= block_is_partially_uptodate
,
3284 .error_remove_page
= generic_error_remove_page
,
3287 static const struct address_space_operations ext4_journalled_aops
= {
3288 .readpage
= ext4_readpage
,
3289 .readpages
= ext4_readpages
,
3290 .writepage
= ext4_writepage
,
3291 .writepages
= ext4_writepages
,
3292 .write_begin
= ext4_write_begin
,
3293 .write_end
= ext4_journalled_write_end
,
3294 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3296 .invalidatepage
= ext4_journalled_invalidatepage
,
3297 .releasepage
= ext4_releasepage
,
3298 .direct_IO
= ext4_direct_IO
,
3299 .is_partially_uptodate
= block_is_partially_uptodate
,
3300 .error_remove_page
= generic_error_remove_page
,
3303 static const struct address_space_operations ext4_da_aops
= {
3304 .readpage
= ext4_readpage
,
3305 .readpages
= ext4_readpages
,
3306 .writepage
= ext4_writepage
,
3307 .writepages
= ext4_writepages
,
3308 .write_begin
= ext4_da_write_begin
,
3309 .write_end
= ext4_da_write_end
,
3311 .invalidatepage
= ext4_da_invalidatepage
,
3312 .releasepage
= ext4_releasepage
,
3313 .direct_IO
= ext4_direct_IO
,
3314 .migratepage
= buffer_migrate_page
,
3315 .is_partially_uptodate
= block_is_partially_uptodate
,
3316 .error_remove_page
= generic_error_remove_page
,
3319 void ext4_set_aops(struct inode
*inode
)
3321 switch (ext4_inode_journal_mode(inode
)) {
3322 case EXT4_INODE_ORDERED_DATA_MODE
:
3323 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3325 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3326 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3328 case EXT4_INODE_JOURNAL_DATA_MODE
:
3329 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3334 if (test_opt(inode
->i_sb
, DELALLOC
))
3335 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3337 inode
->i_mapping
->a_ops
= &ext4_aops
;
3341 * ext4_block_zero_page_range() zeros out a mapping of length 'length'
3342 * starting from file offset 'from'. The range to be zero'd must
3343 * be contained with in one block. If the specified range exceeds
3344 * the end of the block it will be shortened to end of the block
3345 * that cooresponds to 'from'
3347 static int ext4_block_zero_page_range(handle_t
*handle
,
3348 struct address_space
*mapping
, loff_t from
, loff_t length
)
3350 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3351 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3352 unsigned blocksize
, max
, pos
;
3354 struct inode
*inode
= mapping
->host
;
3355 struct buffer_head
*bh
;
3359 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3360 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3364 blocksize
= inode
->i_sb
->s_blocksize
;
3365 max
= blocksize
- (offset
& (blocksize
- 1));
3368 * correct length if it does not fall between
3369 * 'from' and the end of the block
3371 if (length
> max
|| length
< 0)
3374 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3376 if (!page_has_buffers(page
))
3377 create_empty_buffers(page
, blocksize
, 0);
3379 /* Find the buffer that contains "offset" */
3380 bh
= page_buffers(page
);
3382 while (offset
>= pos
) {
3383 bh
= bh
->b_this_page
;
3387 if (buffer_freed(bh
)) {
3388 BUFFER_TRACE(bh
, "freed: skip");
3391 if (!buffer_mapped(bh
)) {
3392 BUFFER_TRACE(bh
, "unmapped");
3393 ext4_get_block(inode
, iblock
, bh
, 0);
3394 /* unmapped? It's a hole - nothing to do */
3395 if (!buffer_mapped(bh
)) {
3396 BUFFER_TRACE(bh
, "still unmapped");
3401 /* Ok, it's mapped. Make sure it's up-to-date */
3402 if (PageUptodate(page
))
3403 set_buffer_uptodate(bh
);
3405 if (!buffer_uptodate(bh
)) {
3407 ll_rw_block(READ
, 1, &bh
);
3409 /* Uhhuh. Read error. Complain and punt. */
3410 if (!buffer_uptodate(bh
))
3413 if (ext4_should_journal_data(inode
)) {
3414 BUFFER_TRACE(bh
, "get write access");
3415 err
= ext4_journal_get_write_access(handle
, bh
);
3419 zero_user(page
, offset
, length
);
3420 BUFFER_TRACE(bh
, "zeroed end of block");
3422 if (ext4_should_journal_data(inode
)) {
3423 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3426 mark_buffer_dirty(bh
);
3427 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
))
3428 err
= ext4_jbd2_file_inode(handle
, inode
);
3433 page_cache_release(page
);
3438 * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
3439 * up to the end of the block which corresponds to `from'.
3440 * This required during truncate. We need to physically zero the tail end
3441 * of that block so it doesn't yield old data if the file is later grown.
3443 int ext4_block_truncate_page(handle_t
*handle
,
3444 struct address_space
*mapping
, loff_t from
)
3446 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
3449 struct inode
*inode
= mapping
->host
;
3451 blocksize
= inode
->i_sb
->s_blocksize
;
3452 length
= blocksize
- (offset
& (blocksize
- 1));
3454 return ext4_block_zero_page_range(handle
, mapping
, from
, length
);
3457 int ext4_zero_partial_blocks(handle_t
*handle
, struct inode
*inode
,
3458 loff_t lstart
, loff_t length
)
3460 struct super_block
*sb
= inode
->i_sb
;
3461 struct address_space
*mapping
= inode
->i_mapping
;
3462 unsigned partial_start
, partial_end
;
3463 ext4_fsblk_t start
, end
;
3464 loff_t byte_end
= (lstart
+ length
- 1);
3467 partial_start
= lstart
& (sb
->s_blocksize
- 1);
3468 partial_end
= byte_end
& (sb
->s_blocksize
- 1);
3470 start
= lstart
>> sb
->s_blocksize_bits
;
3471 end
= byte_end
>> sb
->s_blocksize_bits
;
3473 /* Handle partial zero within the single block */
3475 (partial_start
|| (partial_end
!= sb
->s_blocksize
- 1))) {
3476 err
= ext4_block_zero_page_range(handle
, mapping
,
3480 /* Handle partial zero out on the start of the range */
3481 if (partial_start
) {
3482 err
= ext4_block_zero_page_range(handle
, mapping
,
3483 lstart
, sb
->s_blocksize
);
3487 /* Handle partial zero out on the end of the range */
3488 if (partial_end
!= sb
->s_blocksize
- 1)
3489 err
= ext4_block_zero_page_range(handle
, mapping
,
3490 byte_end
- partial_end
,
3495 int ext4_can_truncate(struct inode
*inode
)
3497 if (S_ISREG(inode
->i_mode
))
3499 if (S_ISDIR(inode
->i_mode
))
3501 if (S_ISLNK(inode
->i_mode
))
3502 return !ext4_inode_is_fast_symlink(inode
);
3507 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3508 * associated with the given offset and length
3510 * @inode: File inode
3511 * @offset: The offset where the hole will begin
3512 * @len: The length of the hole
3514 * Returns: 0 on success or negative on failure
3517 int ext4_punch_hole(struct inode
*inode
, loff_t offset
, loff_t length
)
3519 struct super_block
*sb
= inode
->i_sb
;
3520 ext4_lblk_t first_block
, stop_block
;
3521 struct address_space
*mapping
= inode
->i_mapping
;
3522 loff_t first_block_offset
, last_block_offset
;
3524 unsigned int credits
;
3527 if (!S_ISREG(inode
->i_mode
))
3530 trace_ext4_punch_hole(inode
, offset
, length
, 0);
3533 * Write out all dirty pages to avoid race conditions
3534 * Then release them.
3536 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3537 ret
= filemap_write_and_wait_range(mapping
, offset
,
3538 offset
+ length
- 1);
3543 mutex_lock(&inode
->i_mutex
);
3545 /* No need to punch hole beyond i_size */
3546 if (offset
>= inode
->i_size
)
3550 * If the hole extends beyond i_size, set the hole
3551 * to end after the page that contains i_size
3553 if (offset
+ length
> inode
->i_size
) {
3554 length
= inode
->i_size
+
3555 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3559 if (offset
& (sb
->s_blocksize
- 1) ||
3560 (offset
+ length
) & (sb
->s_blocksize
- 1)) {
3562 * Attach jinode to inode for jbd2 if we do any zeroing of
3565 ret
= ext4_inode_attach_jinode(inode
);
3571 first_block_offset
= round_up(offset
, sb
->s_blocksize
);
3572 last_block_offset
= round_down((offset
+ length
), sb
->s_blocksize
) - 1;
3574 /* Now release the pages and zero block aligned part of pages*/
3575 if (last_block_offset
> first_block_offset
)
3576 truncate_pagecache_range(inode
, first_block_offset
,
3579 /* Wait all existing dio workers, newcomers will block on i_mutex */
3580 ext4_inode_block_unlocked_dio(inode
);
3581 inode_dio_wait(inode
);
3583 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3584 credits
= ext4_writepage_trans_blocks(inode
);
3586 credits
= ext4_blocks_for_truncate(inode
);
3587 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3588 if (IS_ERR(handle
)) {
3589 ret
= PTR_ERR(handle
);
3590 ext4_std_error(sb
, ret
);
3594 ret
= ext4_zero_partial_blocks(handle
, inode
, offset
,
3599 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3600 EXT4_BLOCK_SIZE_BITS(sb
);
3601 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3603 /* If there are no blocks to remove, return now */
3604 if (first_block
>= stop_block
)
3607 down_write(&EXT4_I(inode
)->i_data_sem
);
3608 ext4_discard_preallocations(inode
);
3610 ret
= ext4_es_remove_extent(inode
, first_block
,
3611 stop_block
- first_block
);
3613 up_write(&EXT4_I(inode
)->i_data_sem
);
3617 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3618 ret
= ext4_ext_remove_space(inode
, first_block
,
3621 ret
= ext4_free_hole_blocks(handle
, inode
, first_block
,
3624 up_write(&EXT4_I(inode
)->i_data_sem
);
3626 ext4_handle_sync(handle
);
3628 /* Now release the pages again to reduce race window */
3629 if (last_block_offset
> first_block_offset
)
3630 truncate_pagecache_range(inode
, first_block_offset
,
3633 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3634 ext4_mark_inode_dirty(handle
, inode
);
3636 ext4_journal_stop(handle
);
3638 ext4_inode_resume_unlocked_dio(inode
);
3640 mutex_unlock(&inode
->i_mutex
);
3644 int ext4_inode_attach_jinode(struct inode
*inode
)
3646 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3647 struct jbd2_inode
*jinode
;
3649 if (ei
->jinode
|| !EXT4_SB(inode
->i_sb
)->s_journal
)
3652 jinode
= jbd2_alloc_inode(GFP_KERNEL
);
3653 spin_lock(&inode
->i_lock
);
3656 spin_unlock(&inode
->i_lock
);
3659 ei
->jinode
= jinode
;
3660 jbd2_journal_init_jbd_inode(ei
->jinode
, inode
);
3663 spin_unlock(&inode
->i_lock
);
3664 if (unlikely(jinode
!= NULL
))
3665 jbd2_free_inode(jinode
);
3672 * We block out ext4_get_block() block instantiations across the entire
3673 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3674 * simultaneously on behalf of the same inode.
3676 * As we work through the truncate and commit bits of it to the journal there
3677 * is one core, guiding principle: the file's tree must always be consistent on
3678 * disk. We must be able to restart the truncate after a crash.
3680 * The file's tree may be transiently inconsistent in memory (although it
3681 * probably isn't), but whenever we close off and commit a journal transaction,
3682 * the contents of (the filesystem + the journal) must be consistent and
3683 * restartable. It's pretty simple, really: bottom up, right to left (although
3684 * left-to-right works OK too).
3686 * Note that at recovery time, journal replay occurs *before* the restart of
3687 * truncate against the orphan inode list.
3689 * The committed inode has the new, desired i_size (which is the same as
3690 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3691 * that this inode's truncate did not complete and it will again call
3692 * ext4_truncate() to have another go. So there will be instantiated blocks
3693 * to the right of the truncation point in a crashed ext4 filesystem. But
3694 * that's fine - as long as they are linked from the inode, the post-crash
3695 * ext4_truncate() run will find them and release them.
3697 void ext4_truncate(struct inode
*inode
)
3699 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3700 unsigned int credits
;
3702 struct address_space
*mapping
= inode
->i_mapping
;
3705 * There is a possibility that we're either freeing the inode
3706 * or it's a completely new inode. In those cases we might not
3707 * have i_mutex locked because it's not necessary.
3709 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3710 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3711 trace_ext4_truncate_enter(inode
);
3713 if (!ext4_can_truncate(inode
))
3716 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3718 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3719 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3721 if (ext4_has_inline_data(inode
)) {
3724 ext4_inline_data_truncate(inode
, &has_inline
);
3729 /* If we zero-out tail of the page, we have to create jinode for jbd2 */
3730 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1)) {
3731 if (ext4_inode_attach_jinode(inode
) < 0)
3735 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3736 credits
= ext4_writepage_trans_blocks(inode
);
3738 credits
= ext4_blocks_for_truncate(inode
);
3740 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3741 if (IS_ERR(handle
)) {
3742 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3746 if (inode
->i_size
& (inode
->i_sb
->s_blocksize
- 1))
3747 ext4_block_truncate_page(handle
, mapping
, inode
->i_size
);
3750 * We add the inode to the orphan list, so that if this
3751 * truncate spans multiple transactions, and we crash, we will
3752 * resume the truncate when the filesystem recovers. It also
3753 * marks the inode dirty, to catch the new size.
3755 * Implication: the file must always be in a sane, consistent
3756 * truncatable state while each transaction commits.
3758 if (ext4_orphan_add(handle
, inode
))
3761 down_write(&EXT4_I(inode
)->i_data_sem
);
3763 ext4_discard_preallocations(inode
);
3765 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3766 ext4_ext_truncate(handle
, inode
);
3768 ext4_ind_truncate(handle
, inode
);
3770 up_write(&ei
->i_data_sem
);
3773 ext4_handle_sync(handle
);
3777 * If this was a simple ftruncate() and the file will remain alive,
3778 * then we need to clear up the orphan record which we created above.
3779 * However, if this was a real unlink then we were called by
3780 * ext4_delete_inode(), and we allow that function to clean up the
3781 * orphan info for us.
3784 ext4_orphan_del(handle
, inode
);
3786 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3787 ext4_mark_inode_dirty(handle
, inode
);
3788 ext4_journal_stop(handle
);
3790 trace_ext4_truncate_exit(inode
);
3794 * ext4_get_inode_loc returns with an extra refcount against the inode's
3795 * underlying buffer_head on success. If 'in_mem' is true, we have all
3796 * data in memory that is needed to recreate the on-disk version of this
3799 static int __ext4_get_inode_loc(struct inode
*inode
,
3800 struct ext4_iloc
*iloc
, int in_mem
)
3802 struct ext4_group_desc
*gdp
;
3803 struct buffer_head
*bh
;
3804 struct super_block
*sb
= inode
->i_sb
;
3806 int inodes_per_block
, inode_offset
;
3809 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3812 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3813 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3818 * Figure out the offset within the block group inode table
3820 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3821 inode_offset
= ((inode
->i_ino
- 1) %
3822 EXT4_INODES_PER_GROUP(sb
));
3823 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3824 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3826 bh
= sb_getblk(sb
, block
);
3829 if (!buffer_uptodate(bh
)) {
3833 * If the buffer has the write error flag, we have failed
3834 * to write out another inode in the same block. In this
3835 * case, we don't have to read the block because we may
3836 * read the old inode data successfully.
3838 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3839 set_buffer_uptodate(bh
);
3841 if (buffer_uptodate(bh
)) {
3842 /* someone brought it uptodate while we waited */
3848 * If we have all information of the inode in memory and this
3849 * is the only valid inode in the block, we need not read the
3853 struct buffer_head
*bitmap_bh
;
3856 start
= inode_offset
& ~(inodes_per_block
- 1);
3858 /* Is the inode bitmap in cache? */
3859 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3860 if (unlikely(!bitmap_bh
))
3864 * If the inode bitmap isn't in cache then the
3865 * optimisation may end up performing two reads instead
3866 * of one, so skip it.
3868 if (!buffer_uptodate(bitmap_bh
)) {
3872 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
3873 if (i
== inode_offset
)
3875 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
3879 if (i
== start
+ inodes_per_block
) {
3880 /* all other inodes are free, so skip I/O */
3881 memset(bh
->b_data
, 0, bh
->b_size
);
3882 set_buffer_uptodate(bh
);
3890 * If we need to do any I/O, try to pre-readahead extra
3891 * blocks from the inode table.
3893 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
3894 ext4_fsblk_t b
, end
, table
;
3896 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
3898 table
= ext4_inode_table(sb
, gdp
);
3899 /* s_inode_readahead_blks is always a power of 2 */
3900 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
3904 num
= EXT4_INODES_PER_GROUP(sb
);
3905 if (ext4_has_group_desc_csum(sb
))
3906 num
-= ext4_itable_unused_count(sb
, gdp
);
3907 table
+= num
/ inodes_per_block
;
3911 sb_breadahead(sb
, b
++);
3915 * There are other valid inodes in the buffer, this inode
3916 * has in-inode xattrs, or we don't have this inode in memory.
3917 * Read the block from disk.
3919 trace_ext4_load_inode(inode
);
3921 bh
->b_end_io
= end_buffer_read_sync
;
3922 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
3924 if (!buffer_uptodate(bh
)) {
3925 EXT4_ERROR_INODE_BLOCK(inode
, block
,
3926 "unable to read itable block");
3936 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
3938 /* We have all inode data except xattrs in memory here. */
3939 return __ext4_get_inode_loc(inode
, iloc
,
3940 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
3943 void ext4_set_inode_flags(struct inode
*inode
)
3945 unsigned int flags
= EXT4_I(inode
)->i_flags
;
3946 unsigned int new_fl
= 0;
3948 if (flags
& EXT4_SYNC_FL
)
3950 if (flags
& EXT4_APPEND_FL
)
3952 if (flags
& EXT4_IMMUTABLE_FL
)
3953 new_fl
|= S_IMMUTABLE
;
3954 if (flags
& EXT4_NOATIME_FL
)
3955 new_fl
|= S_NOATIME
;
3956 if (flags
& EXT4_DIRSYNC_FL
)
3957 new_fl
|= S_DIRSYNC
;
3958 inode_set_flags(inode
, new_fl
,
3959 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
);
3962 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
3963 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
3965 unsigned int vfs_fl
;
3966 unsigned long old_fl
, new_fl
;
3969 vfs_fl
= ei
->vfs_inode
.i_flags
;
3970 old_fl
= ei
->i_flags
;
3971 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
3972 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
3974 if (vfs_fl
& S_SYNC
)
3975 new_fl
|= EXT4_SYNC_FL
;
3976 if (vfs_fl
& S_APPEND
)
3977 new_fl
|= EXT4_APPEND_FL
;
3978 if (vfs_fl
& S_IMMUTABLE
)
3979 new_fl
|= EXT4_IMMUTABLE_FL
;
3980 if (vfs_fl
& S_NOATIME
)
3981 new_fl
|= EXT4_NOATIME_FL
;
3982 if (vfs_fl
& S_DIRSYNC
)
3983 new_fl
|= EXT4_DIRSYNC_FL
;
3984 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
3987 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
3988 struct ext4_inode_info
*ei
)
3991 struct inode
*inode
= &(ei
->vfs_inode
);
3992 struct super_block
*sb
= inode
->i_sb
;
3994 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
3995 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
3996 /* we are using combined 48 bit field */
3997 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
3998 le32_to_cpu(raw_inode
->i_blocks_lo
);
3999 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
4000 /* i_blocks represent file system block size */
4001 return i_blocks
<< (inode
->i_blkbits
- 9);
4006 return le32_to_cpu(raw_inode
->i_blocks_lo
);
4010 static inline void ext4_iget_extra_inode(struct inode
*inode
,
4011 struct ext4_inode
*raw_inode
,
4012 struct ext4_inode_info
*ei
)
4014 __le32
*magic
= (void *)raw_inode
+
4015 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
4016 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4017 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
4018 ext4_find_inline_data_nolock(inode
);
4020 EXT4_I(inode
)->i_inline_off
= 0;
4023 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
4025 struct ext4_iloc iloc
;
4026 struct ext4_inode
*raw_inode
;
4027 struct ext4_inode_info
*ei
;
4028 struct inode
*inode
;
4029 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
4035 inode
= iget_locked(sb
, ino
);
4037 return ERR_PTR(-ENOMEM
);
4038 if (!(inode
->i_state
& I_NEW
))
4044 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4047 raw_inode
= ext4_raw_inode(&iloc
);
4049 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4050 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
4051 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
4052 EXT4_INODE_SIZE(inode
->i_sb
)) {
4053 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
4054 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
4055 EXT4_INODE_SIZE(inode
->i_sb
));
4060 ei
->i_extra_isize
= 0;
4062 /* Precompute checksum seed for inode metadata */
4063 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4064 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
)) {
4065 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4067 __le32 inum
= cpu_to_le32(inode
->i_ino
);
4068 __le32 gen
= raw_inode
->i_generation
;
4069 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
4071 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
4075 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
4076 EXT4_ERROR_INODE(inode
, "checksum invalid");
4081 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
4082 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
4083 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
4084 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4085 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
4086 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
4088 i_uid_write(inode
, i_uid
);
4089 i_gid_write(inode
, i_gid
);
4090 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
4092 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
4093 ei
->i_inline_off
= 0;
4094 ei
->i_dir_start_lookup
= 0;
4095 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
4096 /* We now have enough fields to check if the inode was active or not.
4097 * This is needed because nfsd might try to access dead inodes
4098 * the test is that same one that e2fsck uses
4099 * NeilBrown 1999oct15
4101 if (inode
->i_nlink
== 0) {
4102 if ((inode
->i_mode
== 0 ||
4103 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
4104 ino
!= EXT4_BOOT_LOADER_INO
) {
4105 /* this inode is deleted */
4109 /* The only unlinked inodes we let through here have
4110 * valid i_mode and are being read by the orphan
4111 * recovery code: that's fine, we're about to complete
4112 * the process of deleting those.
4113 * OR it is the EXT4_BOOT_LOADER_INO which is
4114 * not initialized on a new filesystem. */
4116 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
4117 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
4118 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
4119 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
4121 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
4122 inode
->i_size
= ext4_isize(raw_inode
);
4123 ei
->i_disksize
= inode
->i_size
;
4125 ei
->i_reserved_quota
= 0;
4127 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4128 ei
->i_block_group
= iloc
.block_group
;
4129 ei
->i_last_alloc_group
= ~0;
4131 * NOTE! The in-memory inode i_data array is in little-endian order
4132 * even on big-endian machines: we do NOT byteswap the block numbers!
4134 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4135 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4136 INIT_LIST_HEAD(&ei
->i_orphan
);
4139 * Set transaction id's of transactions that have to be committed
4140 * to finish f[data]sync. We set them to currently running transaction
4141 * as we cannot be sure that the inode or some of its metadata isn't
4142 * part of the transaction - the inode could have been reclaimed and
4143 * now it is reread from disk.
4146 transaction_t
*transaction
;
4149 read_lock(&journal
->j_state_lock
);
4150 if (journal
->j_running_transaction
)
4151 transaction
= journal
->j_running_transaction
;
4153 transaction
= journal
->j_committing_transaction
;
4155 tid
= transaction
->t_tid
;
4157 tid
= journal
->j_commit_sequence
;
4158 read_unlock(&journal
->j_state_lock
);
4159 ei
->i_sync_tid
= tid
;
4160 ei
->i_datasync_tid
= tid
;
4163 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4164 if (ei
->i_extra_isize
== 0) {
4165 /* The extra space is currently unused. Use it. */
4166 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4167 EXT4_GOOD_OLD_INODE_SIZE
;
4169 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4173 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4174 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4175 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4176 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4178 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4179 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4180 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4181 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4183 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4188 if (ei
->i_file_acl
&&
4189 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4190 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4194 } else if (!ext4_has_inline_data(inode
)) {
4195 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4196 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4197 (S_ISLNK(inode
->i_mode
) &&
4198 !ext4_inode_is_fast_symlink(inode
))))
4199 /* Validate extent which is part of inode */
4200 ret
= ext4_ext_check_inode(inode
);
4201 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4202 (S_ISLNK(inode
->i_mode
) &&
4203 !ext4_inode_is_fast_symlink(inode
))) {
4204 /* Validate block references which are part of inode */
4205 ret
= ext4_ind_check_inode(inode
);
4211 if (S_ISREG(inode
->i_mode
)) {
4212 inode
->i_op
= &ext4_file_inode_operations
;
4213 inode
->i_fop
= &ext4_file_operations
;
4214 ext4_set_aops(inode
);
4215 } else if (S_ISDIR(inode
->i_mode
)) {
4216 inode
->i_op
= &ext4_dir_inode_operations
;
4217 inode
->i_fop
= &ext4_dir_operations
;
4218 } else if (S_ISLNK(inode
->i_mode
)) {
4219 if (ext4_inode_is_fast_symlink(inode
)) {
4220 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4221 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4222 sizeof(ei
->i_data
) - 1);
4224 inode
->i_op
= &ext4_symlink_inode_operations
;
4225 ext4_set_aops(inode
);
4227 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4228 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4229 inode
->i_op
= &ext4_special_inode_operations
;
4230 if (raw_inode
->i_block
[0])
4231 init_special_inode(inode
, inode
->i_mode
,
4232 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4234 init_special_inode(inode
, inode
->i_mode
,
4235 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4236 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4237 make_bad_inode(inode
);
4240 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4244 ext4_set_inode_flags(inode
);
4245 unlock_new_inode(inode
);
4251 return ERR_PTR(ret
);
4254 static int ext4_inode_blocks_set(handle_t
*handle
,
4255 struct ext4_inode
*raw_inode
,
4256 struct ext4_inode_info
*ei
)
4258 struct inode
*inode
= &(ei
->vfs_inode
);
4259 u64 i_blocks
= inode
->i_blocks
;
4260 struct super_block
*sb
= inode
->i_sb
;
4262 if (i_blocks
<= ~0U) {
4264 * i_blocks can be represented in a 32 bit variable
4265 * as multiple of 512 bytes
4267 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4268 raw_inode
->i_blocks_high
= 0;
4269 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4272 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4275 if (i_blocks
<= 0xffffffffffffULL
) {
4277 * i_blocks can be represented in a 48 bit variable
4278 * as multiple of 512 bytes
4280 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4281 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4282 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4284 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4285 /* i_block is stored in file system block size */
4286 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4287 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4288 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4294 * Post the struct inode info into an on-disk inode location in the
4295 * buffer-cache. This gobbles the caller's reference to the
4296 * buffer_head in the inode location struct.
4298 * The caller must have write access to iloc->bh.
4300 static int ext4_do_update_inode(handle_t
*handle
,
4301 struct inode
*inode
,
4302 struct ext4_iloc
*iloc
)
4304 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4305 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4306 struct buffer_head
*bh
= iloc
->bh
;
4307 int err
= 0, rc
, block
;
4308 int need_datasync
= 0;
4312 /* For fields not not tracking in the in-memory inode,
4313 * initialise them to zero for new inodes. */
4314 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4315 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4317 ext4_get_inode_flags(ei
);
4318 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4319 i_uid
= i_uid_read(inode
);
4320 i_gid
= i_gid_read(inode
);
4321 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4322 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4323 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4325 * Fix up interoperability with old kernels. Otherwise, old inodes get
4326 * re-used with the upper 16 bits of the uid/gid intact
4329 raw_inode
->i_uid_high
=
4330 cpu_to_le16(high_16_bits(i_uid
));
4331 raw_inode
->i_gid_high
=
4332 cpu_to_le16(high_16_bits(i_gid
));
4334 raw_inode
->i_uid_high
= 0;
4335 raw_inode
->i_gid_high
= 0;
4338 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4339 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4340 raw_inode
->i_uid_high
= 0;
4341 raw_inode
->i_gid_high
= 0;
4343 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4345 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4346 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4347 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4348 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4350 if (ext4_inode_blocks_set(handle
, raw_inode
, ei
))
4352 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4353 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4354 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
)))
4355 raw_inode
->i_file_acl_high
=
4356 cpu_to_le16(ei
->i_file_acl
>> 32);
4357 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4358 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4359 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4362 if (ei
->i_disksize
> 0x7fffffffULL
) {
4363 struct super_block
*sb
= inode
->i_sb
;
4364 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4365 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4366 EXT4_SB(sb
)->s_es
->s_rev_level
==
4367 cpu_to_le32(EXT4_GOOD_OLD_REV
)) {
4368 /* If this is the first large file
4369 * created, add a flag to the superblock.
4371 err
= ext4_journal_get_write_access(handle
,
4372 EXT4_SB(sb
)->s_sbh
);
4375 ext4_update_dynamic_rev(sb
);
4376 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4377 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4378 ext4_handle_sync(handle
);
4379 err
= ext4_handle_dirty_super(handle
, sb
);
4382 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4383 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4384 if (old_valid_dev(inode
->i_rdev
)) {
4385 raw_inode
->i_block
[0] =
4386 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4387 raw_inode
->i_block
[1] = 0;
4389 raw_inode
->i_block
[0] = 0;
4390 raw_inode
->i_block
[1] =
4391 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4392 raw_inode
->i_block
[2] = 0;
4394 } else if (!ext4_has_inline_data(inode
)) {
4395 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4396 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4399 if (likely(!test_opt2(inode
->i_sb
, HURD_COMPAT
))) {
4400 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4401 if (ei
->i_extra_isize
) {
4402 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4403 raw_inode
->i_version_hi
=
4404 cpu_to_le32(inode
->i_version
>> 32);
4405 raw_inode
->i_extra_isize
=
4406 cpu_to_le16(ei
->i_extra_isize
);
4410 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4412 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4413 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4416 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4418 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4421 ext4_std_error(inode
->i_sb
, err
);
4426 * ext4_write_inode()
4428 * We are called from a few places:
4430 * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files.
4431 * Here, there will be no transaction running. We wait for any running
4432 * transaction to commit.
4434 * - Within flush work (sys_sync(), kupdate and such).
4435 * We wait on commit, if told to.
4437 * - Within iput_final() -> write_inode_now()
4438 * We wait on commit, if told to.
4440 * In all cases it is actually safe for us to return without doing anything,
4441 * because the inode has been copied into a raw inode buffer in
4442 * ext4_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL
4445 * Note that we are absolutely dependent upon all inode dirtiers doing the
4446 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4447 * which we are interested.
4449 * It would be a bug for them to not do this. The code:
4451 * mark_inode_dirty(inode)
4453 * inode->i_size = expr;
4455 * is in error because write_inode() could occur while `stuff()' is running,
4456 * and the new i_size will be lost. Plus the inode will no longer be on the
4457 * superblock's dirty inode list.
4459 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4463 if (WARN_ON_ONCE(current
->flags
& PF_MEMALLOC
))
4466 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4467 if (ext4_journal_current_handle()) {
4468 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4474 * No need to force transaction in WB_SYNC_NONE mode. Also
4475 * ext4_sync_fs() will force the commit after everything is
4478 if (wbc
->sync_mode
!= WB_SYNC_ALL
|| wbc
->for_sync
)
4481 err
= ext4_force_commit(inode
->i_sb
);
4483 struct ext4_iloc iloc
;
4485 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4489 * sync(2) will flush the whole buffer cache. No need to do
4490 * it here separately for each inode.
4492 if (wbc
->sync_mode
== WB_SYNC_ALL
&& !wbc
->for_sync
)
4493 sync_dirty_buffer(iloc
.bh
);
4494 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4495 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4496 "IO error syncing inode");
4505 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4506 * buffers that are attached to a page stradding i_size and are undergoing
4507 * commit. In that case we have to wait for commit to finish and try again.
4509 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4513 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4514 tid_t commit_tid
= 0;
4517 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4519 * All buffers in the last page remain valid? Then there's nothing to
4520 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4523 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4526 page
= find_lock_page(inode
->i_mapping
,
4527 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4530 ret
= __ext4_journalled_invalidatepage(page
, offset
,
4531 PAGE_CACHE_SIZE
- offset
);
4533 page_cache_release(page
);
4537 read_lock(&journal
->j_state_lock
);
4538 if (journal
->j_committing_transaction
)
4539 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4540 read_unlock(&journal
->j_state_lock
);
4542 jbd2_log_wait_commit(journal
, commit_tid
);
4549 * Called from notify_change.
4551 * We want to trap VFS attempts to truncate the file as soon as
4552 * possible. In particular, we want to make sure that when the VFS
4553 * shrinks i_size, we put the inode on the orphan list and modify
4554 * i_disksize immediately, so that during the subsequent flushing of
4555 * dirty pages and freeing of disk blocks, we can guarantee that any
4556 * commit will leave the blocks being flushed in an unused state on
4557 * disk. (On recovery, the inode will get truncated and the blocks will
4558 * be freed, so we have a strong guarantee that no future commit will
4559 * leave these blocks visible to the user.)
4561 * Another thing we have to assure is that if we are in ordered mode
4562 * and inode is still attached to the committing transaction, we must
4563 * we start writeout of all the dirty pages which are being truncated.
4564 * This way we are sure that all the data written in the previous
4565 * transaction are already on disk (truncate waits for pages under
4568 * Called with inode->i_mutex down.
4570 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4572 struct inode
*inode
= dentry
->d_inode
;
4575 const unsigned int ia_valid
= attr
->ia_valid
;
4577 error
= inode_change_ok(inode
, attr
);
4581 if (is_quota_modification(inode
, attr
))
4582 dquot_initialize(inode
);
4583 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4584 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4587 /* (user+group)*(old+new) structure, inode write (sb,
4588 * inode block, ? - but truncate inode update has it) */
4589 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4590 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4591 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4592 if (IS_ERR(handle
)) {
4593 error
= PTR_ERR(handle
);
4596 error
= dquot_transfer(inode
, attr
);
4598 ext4_journal_stop(handle
);
4601 /* Update corresponding info in inode so that everything is in
4602 * one transaction */
4603 if (attr
->ia_valid
& ATTR_UID
)
4604 inode
->i_uid
= attr
->ia_uid
;
4605 if (attr
->ia_valid
& ATTR_GID
)
4606 inode
->i_gid
= attr
->ia_gid
;
4607 error
= ext4_mark_inode_dirty(handle
, inode
);
4608 ext4_journal_stop(handle
);
4611 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4614 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4615 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4617 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4621 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4622 inode_inc_iversion(inode
);
4624 if (S_ISREG(inode
->i_mode
) &&
4625 (attr
->ia_size
< inode
->i_size
)) {
4626 if (ext4_should_order_data(inode
)) {
4627 error
= ext4_begin_ordered_truncate(inode
,
4632 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4633 if (IS_ERR(handle
)) {
4634 error
= PTR_ERR(handle
);
4637 if (ext4_handle_valid(handle
)) {
4638 error
= ext4_orphan_add(handle
, inode
);
4641 down_write(&EXT4_I(inode
)->i_data_sem
);
4642 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4643 rc
= ext4_mark_inode_dirty(handle
, inode
);
4647 * We have to update i_size under i_data_sem together
4648 * with i_disksize to avoid races with writeback code
4649 * running ext4_wb_update_i_disksize().
4652 i_size_write(inode
, attr
->ia_size
);
4653 up_write(&EXT4_I(inode
)->i_data_sem
);
4654 ext4_journal_stop(handle
);
4656 ext4_orphan_del(NULL
, inode
);
4660 i_size_write(inode
, attr
->ia_size
);
4663 * Blocks are going to be removed from the inode. Wait
4664 * for dio in flight. Temporarily disable
4665 * dioread_nolock to prevent livelock.
4668 if (!ext4_should_journal_data(inode
)) {
4669 ext4_inode_block_unlocked_dio(inode
);
4670 inode_dio_wait(inode
);
4671 ext4_inode_resume_unlocked_dio(inode
);
4673 ext4_wait_for_tail_page_commit(inode
);
4676 * Truncate pagecache after we've waited for commit
4677 * in data=journal mode to make pages freeable.
4679 truncate_pagecache(inode
, inode
->i_size
);
4682 * We want to call ext4_truncate() even if attr->ia_size ==
4683 * inode->i_size for cases like truncation of fallocated space
4685 if (attr
->ia_valid
& ATTR_SIZE
)
4686 ext4_truncate(inode
);
4689 setattr_copy(inode
, attr
);
4690 mark_inode_dirty(inode
);
4694 * If the call to ext4_truncate failed to get a transaction handle at
4695 * all, we need to clean up the in-core orphan list manually.
4697 if (orphan
&& inode
->i_nlink
)
4698 ext4_orphan_del(NULL
, inode
);
4700 if (!rc
&& (ia_valid
& ATTR_MODE
))
4701 rc
= posix_acl_chmod(inode
, inode
->i_mode
);
4704 ext4_std_error(inode
->i_sb
, error
);
4710 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4713 struct inode
*inode
;
4714 unsigned long long delalloc_blocks
;
4716 inode
= dentry
->d_inode
;
4717 generic_fillattr(inode
, stat
);
4720 * If there is inline data in the inode, the inode will normally not
4721 * have data blocks allocated (it may have an external xattr block).
4722 * Report at least one sector for such files, so tools like tar, rsync,
4723 * others doen't incorrectly think the file is completely sparse.
4725 if (unlikely(ext4_has_inline_data(inode
)))
4726 stat
->blocks
+= (stat
->size
+ 511) >> 9;
4729 * We can't update i_blocks if the block allocation is delayed
4730 * otherwise in the case of system crash before the real block
4731 * allocation is done, we will have i_blocks inconsistent with
4732 * on-disk file blocks.
4733 * We always keep i_blocks updated together with real
4734 * allocation. But to not confuse with user, stat
4735 * will return the blocks that include the delayed allocation
4736 * blocks for this file.
4738 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4739 EXT4_I(inode
)->i_reserved_data_blocks
);
4740 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
- 9);
4744 static int ext4_index_trans_blocks(struct inode
*inode
, int lblocks
,
4747 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4748 return ext4_ind_trans_blocks(inode
, lblocks
);
4749 return ext4_ext_index_trans_blocks(inode
, pextents
);
4753 * Account for index blocks, block groups bitmaps and block group
4754 * descriptor blocks if modify datablocks and index blocks
4755 * worse case, the indexs blocks spread over different block groups
4757 * If datablocks are discontiguous, they are possible to spread over
4758 * different block groups too. If they are contiguous, with flexbg,
4759 * they could still across block group boundary.
4761 * Also account for superblock, inode, quota and xattr blocks
4763 static int ext4_meta_trans_blocks(struct inode
*inode
, int lblocks
,
4766 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4772 * How many index blocks need to touch to map @lblocks logical blocks
4773 * to @pextents physical extents?
4775 idxblocks
= ext4_index_trans_blocks(inode
, lblocks
, pextents
);
4780 * Now let's see how many group bitmaps and group descriptors need
4783 groups
= idxblocks
+ pextents
;
4785 if (groups
> ngroups
)
4787 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4788 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4790 /* bitmaps and block group descriptor blocks */
4791 ret
+= groups
+ gdpblocks
;
4793 /* Blocks for super block, inode, quota and xattr blocks */
4794 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4800 * Calculate the total number of credits to reserve to fit
4801 * the modification of a single pages into a single transaction,
4802 * which may include multiple chunks of block allocations.
4804 * This could be called via ext4_write_begin()
4806 * We need to consider the worse case, when
4807 * one new block per extent.
4809 int ext4_writepage_trans_blocks(struct inode
*inode
)
4811 int bpp
= ext4_journal_blocks_per_page(inode
);
4814 ret
= ext4_meta_trans_blocks(inode
, bpp
, bpp
);
4816 /* Account for data blocks for journalled mode */
4817 if (ext4_should_journal_data(inode
))
4823 * Calculate the journal credits for a chunk of data modification.
4825 * This is called from DIO, fallocate or whoever calling
4826 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4828 * journal buffers for data blocks are not included here, as DIO
4829 * and fallocate do no need to journal data buffers.
4831 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4833 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4837 * The caller must have previously called ext4_reserve_inode_write().
4838 * Give this, we know that the caller already has write access to iloc->bh.
4840 int ext4_mark_iloc_dirty(handle_t
*handle
,
4841 struct inode
*inode
, struct ext4_iloc
*iloc
)
4845 if (IS_I_VERSION(inode
))
4846 inode_inc_iversion(inode
);
4848 /* the do_update_inode consumes one bh->b_count */
4851 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4852 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4858 * On success, We end up with an outstanding reference count against
4859 * iloc->bh. This _must_ be cleaned up later.
4863 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4864 struct ext4_iloc
*iloc
)
4868 err
= ext4_get_inode_loc(inode
, iloc
);
4870 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4871 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4877 ext4_std_error(inode
->i_sb
, err
);
4882 * Expand an inode by new_extra_isize bytes.
4883 * Returns 0 on success or negative error number on failure.
4885 static int ext4_expand_extra_isize(struct inode
*inode
,
4886 unsigned int new_extra_isize
,
4887 struct ext4_iloc iloc
,
4890 struct ext4_inode
*raw_inode
;
4891 struct ext4_xattr_ibody_header
*header
;
4893 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
4896 raw_inode
= ext4_raw_inode(&iloc
);
4898 header
= IHDR(inode
, raw_inode
);
4900 /* No extended attributes present */
4901 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
4902 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4903 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
4905 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
4909 /* try to expand with EAs present */
4910 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
4915 * What we do here is to mark the in-core inode as clean with respect to inode
4916 * dirtiness (it may still be data-dirty).
4917 * This means that the in-core inode may be reaped by prune_icache
4918 * without having to perform any I/O. This is a very good thing,
4919 * because *any* task may call prune_icache - even ones which
4920 * have a transaction open against a different journal.
4922 * Is this cheating? Not really. Sure, we haven't written the
4923 * inode out, but prune_icache isn't a user-visible syncing function.
4924 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
4925 * we start and wait on commits.
4927 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
4929 struct ext4_iloc iloc
;
4930 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4931 static unsigned int mnt_count
;
4935 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
4936 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
4937 if (ext4_handle_valid(handle
) &&
4938 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
4939 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
4941 * We need extra buffer credits since we may write into EA block
4942 * with this same handle. If journal_extend fails, then it will
4943 * only result in a minor loss of functionality for that inode.
4944 * If this is felt to be critical, then e2fsck should be run to
4945 * force a large enough s_min_extra_isize.
4947 if ((jbd2_journal_extend(handle
,
4948 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
4949 ret
= ext4_expand_extra_isize(inode
,
4950 sbi
->s_want_extra_isize
,
4953 ext4_set_inode_state(inode
,
4954 EXT4_STATE_NO_EXPAND
);
4956 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
4957 ext4_warning(inode
->i_sb
,
4958 "Unable to expand inode %lu. Delete"
4959 " some EAs or run e2fsck.",
4962 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
4968 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
4973 * ext4_dirty_inode() is called from __mark_inode_dirty()
4975 * We're really interested in the case where a file is being extended.
4976 * i_size has been changed by generic_commit_write() and we thus need
4977 * to include the updated inode in the current transaction.
4979 * Also, dquot_alloc_block() will always dirty the inode when blocks
4980 * are allocated to the file.
4982 * If the inode is marked synchronous, we don't honour that here - doing
4983 * so would cause a commit on atime updates, which we don't bother doing.
4984 * We handle synchronous inodes at the highest possible level.
4986 void ext4_dirty_inode(struct inode
*inode
, int flags
)
4990 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
4994 ext4_mark_inode_dirty(handle
, inode
);
4996 ext4_journal_stop(handle
);
5003 * Bind an inode's backing buffer_head into this transaction, to prevent
5004 * it from being flushed to disk early. Unlike
5005 * ext4_reserve_inode_write, this leaves behind no bh reference and
5006 * returns no iloc structure, so the caller needs to repeat the iloc
5007 * lookup to mark the inode dirty later.
5009 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
5011 struct ext4_iloc iloc
;
5015 err
= ext4_get_inode_loc(inode
, &iloc
);
5017 BUFFER_TRACE(iloc
.bh
, "get_write_access");
5018 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
5020 err
= ext4_handle_dirty_metadata(handle
,
5026 ext4_std_error(inode
->i_sb
, err
);
5031 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
5038 * We have to be very careful here: changing a data block's
5039 * journaling status dynamically is dangerous. If we write a
5040 * data block to the journal, change the status and then delete
5041 * that block, we risk forgetting to revoke the old log record
5042 * from the journal and so a subsequent replay can corrupt data.
5043 * So, first we make sure that the journal is empty and that
5044 * nobody is changing anything.
5047 journal
= EXT4_JOURNAL(inode
);
5050 if (is_journal_aborted(journal
))
5052 /* We have to allocate physical blocks for delalloc blocks
5053 * before flushing journal. otherwise delalloc blocks can not
5054 * be allocated any more. even more truncate on delalloc blocks
5055 * could trigger BUG by flushing delalloc blocks in journal.
5056 * There is no delalloc block in non-journal data mode.
5058 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5059 err
= ext4_alloc_da_blocks(inode
);
5064 /* Wait for all existing dio workers */
5065 ext4_inode_block_unlocked_dio(inode
);
5066 inode_dio_wait(inode
);
5068 jbd2_journal_lock_updates(journal
);
5071 * OK, there are no updates running now, and all cached data is
5072 * synced to disk. We are now in a completely consistent state
5073 * which doesn't have anything in the journal, and we know that
5074 * no filesystem updates are running, so it is safe to modify
5075 * the inode's in-core data-journaling state flag now.
5079 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5081 jbd2_journal_flush(journal
);
5082 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5084 ext4_set_aops(inode
);
5086 jbd2_journal_unlock_updates(journal
);
5087 ext4_inode_resume_unlocked_dio(inode
);
5089 /* Finally we can mark the inode as dirty. */
5091 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5093 return PTR_ERR(handle
);
5095 err
= ext4_mark_inode_dirty(handle
, inode
);
5096 ext4_handle_sync(handle
);
5097 ext4_journal_stop(handle
);
5098 ext4_std_error(inode
->i_sb
, err
);
5103 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5105 return !buffer_mapped(bh
);
5108 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5110 struct page
*page
= vmf
->page
;
5114 struct file
*file
= vma
->vm_file
;
5115 struct inode
*inode
= file_inode(file
);
5116 struct address_space
*mapping
= inode
->i_mapping
;
5118 get_block_t
*get_block
;
5121 sb_start_pagefault(inode
->i_sb
);
5122 file_update_time(vma
->vm_file
);
5123 /* Delalloc case is easy... */
5124 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5125 !ext4_should_journal_data(inode
) &&
5126 !ext4_nonda_switch(inode
->i_sb
)) {
5128 ret
= __block_page_mkwrite(vma
, vmf
,
5129 ext4_da_get_block_prep
);
5130 } while (ret
== -ENOSPC
&&
5131 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5136 size
= i_size_read(inode
);
5137 /* Page got truncated from under us? */
5138 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5140 ret
= VM_FAULT_NOPAGE
;
5144 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5145 len
= size
& ~PAGE_CACHE_MASK
;
5147 len
= PAGE_CACHE_SIZE
;
5149 * Return if we have all the buffers mapped. This avoids the need to do
5150 * journal_start/journal_stop which can block and take a long time
5152 if (page_has_buffers(page
)) {
5153 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5155 ext4_bh_unmapped
)) {
5156 /* Wait so that we don't change page under IO */
5157 wait_for_stable_page(page
);
5158 ret
= VM_FAULT_LOCKED
;
5163 /* OK, we need to fill the hole... */
5164 if (ext4_should_dioread_nolock(inode
))
5165 get_block
= ext4_get_block_write
;
5167 get_block
= ext4_get_block
;
5169 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5170 ext4_writepage_trans_blocks(inode
));
5171 if (IS_ERR(handle
)) {
5172 ret
= VM_FAULT_SIGBUS
;
5175 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5176 if (!ret
&& ext4_should_journal_data(inode
)) {
5177 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5178 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5180 ret
= VM_FAULT_SIGBUS
;
5181 ext4_journal_stop(handle
);
5184 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5186 ext4_journal_stop(handle
);
5187 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5190 ret
= block_page_mkwrite_return(ret
);
5192 sb_end_pagefault(inode
->i_sb
);