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 long offset
);
137 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
138 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
139 static int ext4_discard_partial_page_buffers_no_lock(handle_t
*handle
,
140 struct inode
*inode
, struct page
*page
, loff_t from
,
141 loff_t length
, int flags
);
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 (inode
->i_sb
->s_blocksize
>> 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(&inode
->i_data
, 0);
219 ext4_ioend_shutdown(inode
);
223 if (!is_bad_inode(inode
))
224 dquot_initialize(inode
);
226 if (ext4_should_order_data(inode
))
227 ext4_begin_ordered_truncate(inode
, 0);
228 truncate_inode_pages(&inode
->i_data
, 0);
229 ext4_ioend_shutdown(inode
);
231 if (is_bad_inode(inode
))
235 * Protect us against freezing - iput() caller didn't have to have any
236 * protection against it
238 sb_start_intwrite(inode
->i_sb
);
239 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
,
240 ext4_blocks_for_truncate(inode
)+3);
241 if (IS_ERR(handle
)) {
242 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
244 * If we're going to skip the normal cleanup, we still need to
245 * make sure that the in-core orphan linked list is properly
248 ext4_orphan_del(NULL
, inode
);
249 sb_end_intwrite(inode
->i_sb
);
254 ext4_handle_sync(handle
);
256 err
= ext4_mark_inode_dirty(handle
, inode
);
258 ext4_warning(inode
->i_sb
,
259 "couldn't mark inode dirty (err %d)", err
);
263 ext4_truncate(inode
);
266 * ext4_ext_truncate() doesn't reserve any slop when it
267 * restarts journal transactions; therefore there may not be
268 * enough credits left in the handle to remove the inode from
269 * the orphan list and set the dtime field.
271 if (!ext4_handle_has_enough_credits(handle
, 3)) {
272 err
= ext4_journal_extend(handle
, 3);
274 err
= ext4_journal_restart(handle
, 3);
276 ext4_warning(inode
->i_sb
,
277 "couldn't extend journal (err %d)", err
);
279 ext4_journal_stop(handle
);
280 ext4_orphan_del(NULL
, inode
);
281 sb_end_intwrite(inode
->i_sb
);
287 * Kill off the orphan record which ext4_truncate created.
288 * AKPM: I think this can be inside the above `if'.
289 * Note that ext4_orphan_del() has to be able to cope with the
290 * deletion of a non-existent orphan - this is because we don't
291 * know if ext4_truncate() actually created an orphan record.
292 * (Well, we could do this if we need to, but heck - it works)
294 ext4_orphan_del(handle
, inode
);
295 EXT4_I(inode
)->i_dtime
= get_seconds();
298 * One subtle ordering requirement: if anything has gone wrong
299 * (transaction abort, IO errors, whatever), then we can still
300 * do these next steps (the fs will already have been marked as
301 * having errors), but we can't free the inode if the mark_dirty
304 if (ext4_mark_inode_dirty(handle
, inode
))
305 /* If that failed, just do the required in-core inode clear. */
306 ext4_clear_inode(inode
);
308 ext4_free_inode(handle
, inode
);
309 ext4_journal_stop(handle
);
310 sb_end_intwrite(inode
->i_sb
);
313 ext4_clear_inode(inode
); /* We must guarantee clearing of inode... */
317 qsize_t
*ext4_get_reserved_space(struct inode
*inode
)
319 return &EXT4_I(inode
)->i_reserved_quota
;
324 * Calculate the number of metadata blocks need to reserve
325 * to allocate a block located at @lblock
327 static int ext4_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
329 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
330 return ext4_ext_calc_metadata_amount(inode
, lblock
);
332 return ext4_ind_calc_metadata_amount(inode
, lblock
);
336 * Called with i_data_sem down, which is important since we can call
337 * ext4_discard_preallocations() from here.
339 void ext4_da_update_reserve_space(struct inode
*inode
,
340 int used
, int quota_claim
)
342 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
343 struct ext4_inode_info
*ei
= EXT4_I(inode
);
345 spin_lock(&ei
->i_block_reservation_lock
);
346 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
347 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
348 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
349 "with only %d reserved data blocks",
350 __func__
, inode
->i_ino
, used
,
351 ei
->i_reserved_data_blocks
);
353 used
= ei
->i_reserved_data_blocks
;
356 if (unlikely(ei
->i_allocated_meta_blocks
> ei
->i_reserved_meta_blocks
)) {
357 ext4_warning(inode
->i_sb
, "ino %lu, allocated %d "
358 "with only %d reserved metadata blocks "
359 "(releasing %d blocks with reserved %d data blocks)",
360 inode
->i_ino
, ei
->i_allocated_meta_blocks
,
361 ei
->i_reserved_meta_blocks
, used
,
362 ei
->i_reserved_data_blocks
);
364 ei
->i_allocated_meta_blocks
= ei
->i_reserved_meta_blocks
;
367 /* Update per-inode reservations */
368 ei
->i_reserved_data_blocks
-= used
;
369 ei
->i_reserved_meta_blocks
-= ei
->i_allocated_meta_blocks
;
370 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
371 used
+ ei
->i_allocated_meta_blocks
);
372 ei
->i_allocated_meta_blocks
= 0;
374 if (ei
->i_reserved_data_blocks
== 0) {
376 * We can release all of the reserved metadata blocks
377 * only when we have written all of the delayed
380 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
381 ei
->i_reserved_meta_blocks
);
382 ei
->i_reserved_meta_blocks
= 0;
383 ei
->i_da_metadata_calc_len
= 0;
385 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
387 /* Update quota subsystem for data blocks */
389 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
392 * We did fallocate with an offset that is already delayed
393 * allocated. So on delayed allocated writeback we should
394 * not re-claim the quota for fallocated blocks.
396 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
400 * If we have done all the pending block allocations and if
401 * there aren't any writers on the inode, we can discard the
402 * inode's preallocations.
404 if ((ei
->i_reserved_data_blocks
== 0) &&
405 (atomic_read(&inode
->i_writecount
) == 0))
406 ext4_discard_preallocations(inode
);
409 static int __check_block_validity(struct inode
*inode
, const char *func
,
411 struct ext4_map_blocks
*map
)
413 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
415 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
416 "lblock %lu mapped to illegal pblock "
417 "(length %d)", (unsigned long) map
->m_lblk
,
424 #define check_block_validity(inode, map) \
425 __check_block_validity((inode), __func__, __LINE__, (map))
428 * Return the number of contiguous dirty pages in a given inode
429 * starting at page frame idx.
431 static pgoff_t
ext4_num_dirty_pages(struct inode
*inode
, pgoff_t idx
,
432 unsigned int max_pages
)
434 struct address_space
*mapping
= inode
->i_mapping
;
438 int i
, nr_pages
, done
= 0;
442 pagevec_init(&pvec
, 0);
445 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
447 (pgoff_t
)PAGEVEC_SIZE
);
450 for (i
= 0; i
< nr_pages
; i
++) {
451 struct page
*page
= pvec
.pages
[i
];
452 struct buffer_head
*bh
, *head
;
455 if (unlikely(page
->mapping
!= mapping
) ||
457 PageWriteback(page
) ||
458 page
->index
!= idx
) {
463 if (page_has_buffers(page
)) {
464 bh
= head
= page_buffers(page
);
466 if (!buffer_delay(bh
) &&
467 !buffer_unwritten(bh
))
469 bh
= bh
->b_this_page
;
470 } while (!done
&& (bh
!= head
));
477 if (num
>= max_pages
) {
482 pagevec_release(&pvec
);
487 #ifdef ES_AGGRESSIVE_TEST
488 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
490 struct ext4_map_blocks
*es_map
,
491 struct ext4_map_blocks
*map
,
498 * There is a race window that the result is not the same.
499 * e.g. xfstests #223 when dioread_nolock enables. The reason
500 * is that we lookup a block mapping in extent status tree with
501 * out taking i_data_sem. So at the time the unwritten extent
502 * could be converted.
504 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
505 down_read((&EXT4_I(inode
)->i_data_sem
));
506 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
507 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
508 EXT4_GET_BLOCKS_KEEP_SIZE
);
510 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
511 EXT4_GET_BLOCKS_KEEP_SIZE
);
513 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
514 up_read((&EXT4_I(inode
)->i_data_sem
));
516 * Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
517 * because it shouldn't be marked in es_map->m_flags.
519 map
->m_flags
&= ~(EXT4_MAP_FROM_CLUSTER
| EXT4_MAP_BOUNDARY
);
522 * We don't check m_len because extent will be collpased in status
523 * tree. So the m_len might not equal.
525 if (es_map
->m_lblk
!= map
->m_lblk
||
526 es_map
->m_flags
!= map
->m_flags
||
527 es_map
->m_pblk
!= map
->m_pblk
) {
528 printk("ES cache assertation failed for inode: %lu "
529 "es_cached ex [%d/%d/%llu/%x] != "
530 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
531 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
532 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
533 map
->m_len
, map
->m_pblk
, map
->m_flags
,
537 #endif /* ES_AGGRESSIVE_TEST */
540 * The ext4_map_blocks() function tries to look up the requested blocks,
541 * and returns if the blocks are already mapped.
543 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
544 * and store the allocated blocks in the result buffer head and mark it
547 * If file type is extents based, it will call ext4_ext_map_blocks(),
548 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
551 * On success, it returns the number of blocks being mapped or allocate.
552 * if create==0 and the blocks are pre-allocated and uninitialized block,
553 * the result buffer head is unmapped. If the create ==1, it will make sure
554 * the buffer head is mapped.
556 * It returns 0 if plain look up failed (blocks have not been allocated), in
557 * that case, buffer head is unmapped
559 * It returns the error in case of allocation failure.
561 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
562 struct ext4_map_blocks
*map
, int flags
)
564 struct extent_status es
;
566 #ifdef ES_AGGRESSIVE_TEST
567 struct ext4_map_blocks orig_map
;
569 memcpy(&orig_map
, map
, sizeof(*map
));
573 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
574 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
575 (unsigned long) map
->m_lblk
);
577 /* Lookup extent status tree firstly */
578 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
579 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
580 map
->m_pblk
= ext4_es_pblock(&es
) +
581 map
->m_lblk
- es
.es_lblk
;
582 map
->m_flags
|= ext4_es_is_written(&es
) ?
583 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
584 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
585 if (retval
> map
->m_len
)
588 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
593 #ifdef ES_AGGRESSIVE_TEST
594 ext4_map_blocks_es_recheck(handle
, inode
, map
,
601 * Try to see if we can get the block without requesting a new
604 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
605 down_read((&EXT4_I(inode
)->i_data_sem
));
606 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
607 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
608 EXT4_GET_BLOCKS_KEEP_SIZE
);
610 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
611 EXT4_GET_BLOCKS_KEEP_SIZE
);
615 unsigned long long status
;
617 #ifdef ES_AGGRESSIVE_TEST
618 if (retval
!= map
->m_len
) {
619 printk("ES len assertation failed for inode: %lu "
620 "retval %d != map->m_len %d "
621 "in %s (lookup)\n", inode
->i_ino
, retval
,
622 map
->m_len
, __func__
);
626 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
627 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
628 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
629 ext4_find_delalloc_range(inode
, map
->m_lblk
,
630 map
->m_lblk
+ map
->m_len
- 1))
631 status
|= EXTENT_STATUS_DELAYED
;
632 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
633 map
->m_len
, map
->m_pblk
, status
);
637 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
638 up_read((&EXT4_I(inode
)->i_data_sem
));
641 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
642 int ret
= check_block_validity(inode
, map
);
647 /* If it is only a block(s) look up */
648 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
652 * Returns if the blocks have already allocated
654 * Note that if blocks have been preallocated
655 * ext4_ext_get_block() returns the create = 0
656 * with buffer head unmapped.
658 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
662 * Here we clear m_flags because after allocating an new extent,
663 * it will be set again.
665 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
668 * New blocks allocate and/or writing to uninitialized extent
669 * will possibly result in updating i_data, so we take
670 * the write lock of i_data_sem, and call get_blocks()
671 * with create == 1 flag.
673 down_write((&EXT4_I(inode
)->i_data_sem
));
676 * if the caller is from delayed allocation writeout path
677 * we have already reserved fs blocks for allocation
678 * let the underlying get_block() function know to
679 * avoid double accounting
681 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
682 ext4_set_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
684 * We need to check for EXT4 here because migrate
685 * could have changed the inode type in between
687 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
688 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
690 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
692 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
694 * We allocated new blocks which will result in
695 * i_data's format changing. Force the migrate
696 * to fail by clearing migrate flags
698 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
702 * Update reserved blocks/metadata blocks after successful
703 * block allocation which had been deferred till now. We don't
704 * support fallocate for non extent files. So we can update
705 * reserve space here.
708 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
709 ext4_da_update_reserve_space(inode
, retval
, 1);
711 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
712 ext4_clear_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
716 unsigned long long status
;
718 #ifdef ES_AGGRESSIVE_TEST
719 if (retval
!= map
->m_len
) {
720 printk("ES len assertation failed for inode: %lu "
721 "retval %d != map->m_len %d "
722 "in %s (allocation)\n", inode
->i_ino
, retval
,
723 map
->m_len
, __func__
);
728 * If the extent has been zeroed out, we don't need to update
729 * extent status tree.
731 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
732 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
733 if (ext4_es_is_written(&es
))
736 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
737 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
738 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
739 ext4_find_delalloc_range(inode
, map
->m_lblk
,
740 map
->m_lblk
+ map
->m_len
- 1))
741 status
|= EXTENT_STATUS_DELAYED
;
742 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
743 map
->m_pblk
, status
);
749 up_write((&EXT4_I(inode
)->i_data_sem
));
750 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
751 int ret
= check_block_validity(inode
, map
);
758 /* Maximum number of blocks we map for direct IO at once. */
759 #define DIO_MAX_BLOCKS 4096
761 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
762 struct buffer_head
*bh
, int flags
)
764 handle_t
*handle
= ext4_journal_current_handle();
765 struct ext4_map_blocks map
;
766 int ret
= 0, started
= 0;
769 if (ext4_has_inline_data(inode
))
773 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
775 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
776 /* Direct IO write... */
777 if (map
.m_len
> DIO_MAX_BLOCKS
)
778 map
.m_len
= DIO_MAX_BLOCKS
;
779 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
780 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
782 if (IS_ERR(handle
)) {
783 ret
= PTR_ERR(handle
);
789 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
791 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
792 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
793 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
797 ext4_journal_stop(handle
);
801 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
802 struct buffer_head
*bh
, int create
)
804 return _ext4_get_block(inode
, iblock
, bh
,
805 create
? EXT4_GET_BLOCKS_CREATE
: 0);
809 * `handle' can be NULL if create is zero
811 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
812 ext4_lblk_t block
, int create
, int *errp
)
814 struct ext4_map_blocks map
;
815 struct buffer_head
*bh
;
818 J_ASSERT(handle
!= NULL
|| create
== 0);
822 err
= ext4_map_blocks(handle
, inode
, &map
,
823 create
? EXT4_GET_BLOCKS_CREATE
: 0);
825 /* ensure we send some value back into *errp */
828 if (create
&& err
== 0)
829 err
= -ENOSPC
; /* should never happen */
835 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
840 if (map
.m_flags
& EXT4_MAP_NEW
) {
841 J_ASSERT(create
!= 0);
842 J_ASSERT(handle
!= NULL
);
845 * Now that we do not always journal data, we should
846 * keep in mind whether this should always journal the
847 * new buffer as metadata. For now, regular file
848 * writes use ext4_get_block instead, so it's not a
852 BUFFER_TRACE(bh
, "call get_create_access");
853 fatal
= ext4_journal_get_create_access(handle
, bh
);
854 if (!fatal
&& !buffer_uptodate(bh
)) {
855 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
856 set_buffer_uptodate(bh
);
859 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
860 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
864 BUFFER_TRACE(bh
, "not a new buffer");
874 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
875 ext4_lblk_t block
, int create
, int *err
)
877 struct buffer_head
*bh
;
879 bh
= ext4_getblk(handle
, inode
, block
, create
, err
);
882 if (buffer_uptodate(bh
))
884 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
886 if (buffer_uptodate(bh
))
893 int ext4_walk_page_buffers(handle_t
*handle
,
894 struct buffer_head
*head
,
898 int (*fn
)(handle_t
*handle
,
899 struct buffer_head
*bh
))
901 struct buffer_head
*bh
;
902 unsigned block_start
, block_end
;
903 unsigned blocksize
= head
->b_size
;
905 struct buffer_head
*next
;
907 for (bh
= head
, block_start
= 0;
908 ret
== 0 && (bh
!= head
|| !block_start
);
909 block_start
= block_end
, bh
= next
) {
910 next
= bh
->b_this_page
;
911 block_end
= block_start
+ blocksize
;
912 if (block_end
<= from
|| block_start
>= to
) {
913 if (partial
&& !buffer_uptodate(bh
))
917 err
= (*fn
)(handle
, bh
);
925 * To preserve ordering, it is essential that the hole instantiation and
926 * the data write be encapsulated in a single transaction. We cannot
927 * close off a transaction and start a new one between the ext4_get_block()
928 * and the commit_write(). So doing the jbd2_journal_start at the start of
929 * prepare_write() is the right place.
931 * Also, this function can nest inside ext4_writepage(). In that case, we
932 * *know* that ext4_writepage() has generated enough buffer credits to do the
933 * whole page. So we won't block on the journal in that case, which is good,
934 * because the caller may be PF_MEMALLOC.
936 * By accident, ext4 can be reentered when a transaction is open via
937 * quota file writes. If we were to commit the transaction while thus
938 * reentered, there can be a deadlock - we would be holding a quota
939 * lock, and the commit would never complete if another thread had a
940 * transaction open and was blocking on the quota lock - a ranking
943 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
944 * will _not_ run commit under these circumstances because handle->h_ref
945 * is elevated. We'll still have enough credits for the tiny quotafile
948 int do_journal_get_write_access(handle_t
*handle
,
949 struct buffer_head
*bh
)
951 int dirty
= buffer_dirty(bh
);
954 if (!buffer_mapped(bh
) || buffer_freed(bh
))
957 * __block_write_begin() could have dirtied some buffers. Clean
958 * the dirty bit as jbd2_journal_get_write_access() could complain
959 * otherwise about fs integrity issues. Setting of the dirty bit
960 * by __block_write_begin() isn't a real problem here as we clear
961 * the bit before releasing a page lock and thus writeback cannot
962 * ever write the buffer.
965 clear_buffer_dirty(bh
);
966 ret
= ext4_journal_get_write_access(handle
, bh
);
968 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
972 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
973 struct buffer_head
*bh_result
, int create
);
974 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
975 loff_t pos
, unsigned len
, unsigned flags
,
976 struct page
**pagep
, void **fsdata
)
978 struct inode
*inode
= mapping
->host
;
979 int ret
, needed_blocks
;
986 trace_ext4_write_begin(inode
, pos
, len
, flags
);
988 * Reserve one block more for addition to orphan list in case
989 * we allocate blocks but write fails for some reason
991 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
992 index
= pos
>> PAGE_CACHE_SHIFT
;
993 from
= pos
& (PAGE_CACHE_SIZE
- 1);
996 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
997 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
1006 * grab_cache_page_write_begin() can take a long time if the
1007 * system is thrashing due to memory pressure, or if the page
1008 * is being written back. So grab it first before we start
1009 * the transaction handle. This also allows us to allocate
1010 * the page (if needed) without using GFP_NOFS.
1013 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
1019 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
1020 if (IS_ERR(handle
)) {
1021 page_cache_release(page
);
1022 return PTR_ERR(handle
);
1026 if (page
->mapping
!= mapping
) {
1027 /* The page got truncated from under us */
1029 page_cache_release(page
);
1030 ext4_journal_stop(handle
);
1033 wait_on_page_writeback(page
);
1035 if (ext4_should_dioread_nolock(inode
))
1036 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
1038 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
1040 if (!ret
&& ext4_should_journal_data(inode
)) {
1041 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
1043 do_journal_get_write_access
);
1049 * __block_write_begin may have instantiated a few blocks
1050 * outside i_size. Trim these off again. Don't need
1051 * i_size_read because we hold i_mutex.
1053 * Add inode to orphan list in case we crash before
1056 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1057 ext4_orphan_add(handle
, inode
);
1059 ext4_journal_stop(handle
);
1060 if (pos
+ len
> inode
->i_size
) {
1061 ext4_truncate_failed_write(inode
);
1063 * If truncate failed early the inode might
1064 * still be on the orphan list; we need to
1065 * make sure the inode is removed from the
1066 * orphan list in that case.
1069 ext4_orphan_del(NULL
, inode
);
1072 if (ret
== -ENOSPC
&&
1073 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
1075 page_cache_release(page
);
1082 /* For write_end() in data=journal mode */
1083 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1086 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1088 set_buffer_uptodate(bh
);
1089 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1090 clear_buffer_meta(bh
);
1091 clear_buffer_prio(bh
);
1096 * We need to pick up the new inode size which generic_commit_write gave us
1097 * `file' can be NULL - eg, when called from page_symlink().
1099 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1100 * buffers are managed internally.
1102 static int ext4_write_end(struct file
*file
,
1103 struct address_space
*mapping
,
1104 loff_t pos
, unsigned len
, unsigned copied
,
1105 struct page
*page
, void *fsdata
)
1107 handle_t
*handle
= ext4_journal_current_handle();
1108 struct inode
*inode
= mapping
->host
;
1110 int i_size_changed
= 0;
1112 trace_ext4_write_end(inode
, pos
, len
, copied
);
1113 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1114 ret
= ext4_jbd2_file_inode(handle
, inode
);
1117 page_cache_release(page
);
1122 if (ext4_has_inline_data(inode
)) {
1123 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1129 copied
= block_write_end(file
, mapping
, pos
,
1130 len
, copied
, page
, fsdata
);
1133 * No need to use i_size_read() here, the i_size
1134 * cannot change under us because we hole i_mutex.
1136 * But it's important to update i_size while still holding page lock:
1137 * page writeout could otherwise come in and zero beyond i_size.
1139 if (pos
+ copied
> inode
->i_size
) {
1140 i_size_write(inode
, pos
+ copied
);
1144 if (pos
+ copied
> EXT4_I(inode
)->i_disksize
) {
1145 /* We need to mark inode dirty even if
1146 * new_i_size is less that inode->i_size
1147 * but greater than i_disksize. (hint delalloc)
1149 ext4_update_i_disksize(inode
, (pos
+ copied
));
1153 page_cache_release(page
);
1156 * Don't mark the inode dirty under page lock. First, it unnecessarily
1157 * makes the holding time of page lock longer. Second, it forces lock
1158 * ordering of page lock and transaction start for journaling
1162 ext4_mark_inode_dirty(handle
, inode
);
1166 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1167 /* if we have allocated more blocks and copied
1168 * less. We will have blocks allocated outside
1169 * inode->i_size. So truncate them
1171 ext4_orphan_add(handle
, inode
);
1173 ret2
= ext4_journal_stop(handle
);
1177 if (pos
+ len
> inode
->i_size
) {
1178 ext4_truncate_failed_write(inode
);
1180 * If truncate failed early the inode might still be
1181 * on the orphan list; we need to make sure the inode
1182 * is removed from the orphan list in that case.
1185 ext4_orphan_del(NULL
, inode
);
1188 return ret
? ret
: copied
;
1191 static int ext4_journalled_write_end(struct file
*file
,
1192 struct address_space
*mapping
,
1193 loff_t pos
, unsigned len
, unsigned copied
,
1194 struct page
*page
, void *fsdata
)
1196 handle_t
*handle
= ext4_journal_current_handle();
1197 struct inode
*inode
= mapping
->host
;
1203 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1204 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1207 BUG_ON(!ext4_handle_valid(handle
));
1209 if (ext4_has_inline_data(inode
))
1210 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1214 if (!PageUptodate(page
))
1216 page_zero_new_buffers(page
, from
+copied
, to
);
1219 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1220 to
, &partial
, write_end_fn
);
1222 SetPageUptodate(page
);
1224 new_i_size
= pos
+ copied
;
1225 if (new_i_size
> inode
->i_size
)
1226 i_size_write(inode
, pos
+copied
);
1227 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1228 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1229 if (new_i_size
> EXT4_I(inode
)->i_disksize
) {
1230 ext4_update_i_disksize(inode
, new_i_size
);
1231 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1237 page_cache_release(page
);
1238 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1239 /* if we have allocated more blocks and copied
1240 * less. We will have blocks allocated outside
1241 * inode->i_size. So truncate them
1243 ext4_orphan_add(handle
, inode
);
1245 ret2
= ext4_journal_stop(handle
);
1248 if (pos
+ len
> inode
->i_size
) {
1249 ext4_truncate_failed_write(inode
);
1251 * If truncate failed early the inode might still be
1252 * on the orphan list; we need to make sure the inode
1253 * is removed from the orphan list in that case.
1256 ext4_orphan_del(NULL
, inode
);
1259 return ret
? ret
: copied
;
1263 * Reserve a metadata for a single block located at lblock
1265 static int ext4_da_reserve_metadata(struct inode
*inode
, ext4_lblk_t lblock
)
1267 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1268 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1269 unsigned int md_needed
;
1270 ext4_lblk_t save_last_lblock
;
1274 * recalculate the amount of metadata blocks to reserve
1275 * in order to allocate nrblocks
1276 * worse case is one extent per block
1278 spin_lock(&ei
->i_block_reservation_lock
);
1280 * ext4_calc_metadata_amount() has side effects, which we have
1281 * to be prepared undo if we fail to claim space.
1283 save_len
= ei
->i_da_metadata_calc_len
;
1284 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1285 md_needed
= EXT4_NUM_B2C(sbi
,
1286 ext4_calc_metadata_amount(inode
, lblock
));
1287 trace_ext4_da_reserve_space(inode
, md_needed
);
1290 * We do still charge estimated metadata to the sb though;
1291 * we cannot afford to run out of free blocks.
1293 if (ext4_claim_free_clusters(sbi
, md_needed
, 0)) {
1294 ei
->i_da_metadata_calc_len
= save_len
;
1295 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1296 spin_unlock(&ei
->i_block_reservation_lock
);
1299 ei
->i_reserved_meta_blocks
+= md_needed
;
1300 spin_unlock(&ei
->i_block_reservation_lock
);
1302 return 0; /* success */
1306 * Reserve a single cluster located at lblock
1308 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1310 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1311 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1312 unsigned int md_needed
;
1314 ext4_lblk_t save_last_lblock
;
1318 * We will charge metadata quota at writeout time; this saves
1319 * us from metadata over-estimation, though we may go over by
1320 * a small amount in the end. Here we just reserve for data.
1322 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1327 * recalculate the amount of metadata blocks to reserve
1328 * in order to allocate nrblocks
1329 * worse case is one extent per block
1331 spin_lock(&ei
->i_block_reservation_lock
);
1333 * ext4_calc_metadata_amount() has side effects, which we have
1334 * to be prepared undo if we fail to claim space.
1336 save_len
= ei
->i_da_metadata_calc_len
;
1337 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1338 md_needed
= EXT4_NUM_B2C(sbi
,
1339 ext4_calc_metadata_amount(inode
, lblock
));
1340 trace_ext4_da_reserve_space(inode
, md_needed
);
1343 * We do still charge estimated metadata to the sb though;
1344 * we cannot afford to run out of free blocks.
1346 if (ext4_claim_free_clusters(sbi
, md_needed
+ 1, 0)) {
1347 ei
->i_da_metadata_calc_len
= save_len
;
1348 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1349 spin_unlock(&ei
->i_block_reservation_lock
);
1350 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1353 ei
->i_reserved_data_blocks
++;
1354 ei
->i_reserved_meta_blocks
+= md_needed
;
1355 spin_unlock(&ei
->i_block_reservation_lock
);
1357 return 0; /* success */
1360 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1362 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1363 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1366 return; /* Nothing to release, exit */
1368 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1370 trace_ext4_da_release_space(inode
, to_free
);
1371 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1373 * if there aren't enough reserved blocks, then the
1374 * counter is messed up somewhere. Since this
1375 * function is called from invalidate page, it's
1376 * harmless to return without any action.
1378 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1379 "ino %lu, to_free %d with only %d reserved "
1380 "data blocks", inode
->i_ino
, to_free
,
1381 ei
->i_reserved_data_blocks
);
1383 to_free
= ei
->i_reserved_data_blocks
;
1385 ei
->i_reserved_data_blocks
-= to_free
;
1387 if (ei
->i_reserved_data_blocks
== 0) {
1389 * We can release all of the reserved metadata blocks
1390 * only when we have written all of the delayed
1391 * allocation blocks.
1392 * Note that in case of bigalloc, i_reserved_meta_blocks,
1393 * i_reserved_data_blocks, etc. refer to number of clusters.
1395 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
1396 ei
->i_reserved_meta_blocks
);
1397 ei
->i_reserved_meta_blocks
= 0;
1398 ei
->i_da_metadata_calc_len
= 0;
1401 /* update fs dirty data blocks counter */
1402 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1404 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1406 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1409 static void ext4_da_page_release_reservation(struct page
*page
,
1410 unsigned long offset
)
1413 struct buffer_head
*head
, *bh
;
1414 unsigned int curr_off
= 0;
1415 struct inode
*inode
= page
->mapping
->host
;
1416 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1420 head
= page_buffers(page
);
1423 unsigned int next_off
= curr_off
+ bh
->b_size
;
1425 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1427 clear_buffer_delay(bh
);
1429 curr_off
= next_off
;
1430 } while ((bh
= bh
->b_this_page
) != head
);
1433 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1434 ext4_es_remove_extent(inode
, lblk
, to_release
);
1437 /* If we have released all the blocks belonging to a cluster, then we
1438 * need to release the reserved space for that cluster. */
1439 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1440 while (num_clusters
> 0) {
1441 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1442 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1443 if (sbi
->s_cluster_ratio
== 1 ||
1444 !ext4_find_delalloc_cluster(inode
, lblk
))
1445 ext4_da_release_space(inode
, 1);
1452 * Delayed allocation stuff
1456 * mpage_da_submit_io - walks through extent of pages and try to write
1457 * them with writepage() call back
1459 * @mpd->inode: inode
1460 * @mpd->first_page: first page of the extent
1461 * @mpd->next_page: page after the last page of the extent
1463 * By the time mpage_da_submit_io() is called we expect all blocks
1464 * to be allocated. this may be wrong if allocation failed.
1466 * As pages are already locked by write_cache_pages(), we can't use it
1468 static int mpage_da_submit_io(struct mpage_da_data
*mpd
,
1469 struct ext4_map_blocks
*map
)
1471 struct pagevec pvec
;
1472 unsigned long index
, end
;
1473 int ret
= 0, err
, nr_pages
, i
;
1474 struct inode
*inode
= mpd
->inode
;
1475 struct address_space
*mapping
= inode
->i_mapping
;
1476 loff_t size
= i_size_read(inode
);
1477 unsigned int len
, block_start
;
1478 struct buffer_head
*bh
, *page_bufs
= NULL
;
1479 sector_t pblock
= 0, cur_logical
= 0;
1480 struct ext4_io_submit io_submit
;
1482 BUG_ON(mpd
->next_page
<= mpd
->first_page
);
1483 memset(&io_submit
, 0, sizeof(io_submit
));
1485 * We need to start from the first_page to the next_page - 1
1486 * to make sure we also write the mapped dirty buffer_heads.
1487 * If we look at mpd->b_blocknr we would only be looking
1488 * at the currently mapped buffer_heads.
1490 index
= mpd
->first_page
;
1491 end
= mpd
->next_page
- 1;
1493 pagevec_init(&pvec
, 0);
1494 while (index
<= end
) {
1495 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1498 for (i
= 0; i
< nr_pages
; i
++) {
1500 struct page
*page
= pvec
.pages
[i
];
1502 index
= page
->index
;
1506 if (index
== size
>> PAGE_CACHE_SHIFT
)
1507 len
= size
& ~PAGE_CACHE_MASK
;
1509 len
= PAGE_CACHE_SIZE
;
1511 cur_logical
= index
<< (PAGE_CACHE_SHIFT
-
1513 pblock
= map
->m_pblk
+ (cur_logical
-
1518 BUG_ON(!PageLocked(page
));
1519 BUG_ON(PageWriteback(page
));
1521 bh
= page_bufs
= page_buffers(page
);
1524 if (map
&& (cur_logical
>= map
->m_lblk
) &&
1525 (cur_logical
<= (map
->m_lblk
+
1526 (map
->m_len
- 1)))) {
1527 if (buffer_delay(bh
)) {
1528 clear_buffer_delay(bh
);
1529 bh
->b_blocknr
= pblock
;
1531 if (buffer_unwritten(bh
) ||
1533 BUG_ON(bh
->b_blocknr
!= pblock
);
1534 if (map
->m_flags
& EXT4_MAP_UNINIT
)
1535 set_buffer_uninit(bh
);
1536 clear_buffer_unwritten(bh
);
1540 * skip page if block allocation undone and
1543 if (ext4_bh_delay_or_unwritten(NULL
, bh
))
1545 bh
= bh
->b_this_page
;
1546 block_start
+= bh
->b_size
;
1549 } while (bh
!= page_bufs
);
1556 clear_page_dirty_for_io(page
);
1557 err
= ext4_bio_write_page(&io_submit
, page
, len
,
1560 mpd
->pages_written
++;
1562 * In error case, we have to continue because
1563 * remaining pages are still locked
1568 pagevec_release(&pvec
);
1570 ext4_io_submit(&io_submit
);
1574 static void ext4_da_block_invalidatepages(struct mpage_da_data
*mpd
)
1578 struct pagevec pvec
;
1579 struct inode
*inode
= mpd
->inode
;
1580 struct address_space
*mapping
= inode
->i_mapping
;
1581 ext4_lblk_t start
, last
;
1583 index
= mpd
->first_page
;
1584 end
= mpd
->next_page
- 1;
1586 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1587 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1588 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1590 pagevec_init(&pvec
, 0);
1591 while (index
<= end
) {
1592 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1595 for (i
= 0; i
< nr_pages
; i
++) {
1596 struct page
*page
= pvec
.pages
[i
];
1597 if (page
->index
> end
)
1599 BUG_ON(!PageLocked(page
));
1600 BUG_ON(PageWriteback(page
));
1601 block_invalidatepage(page
, 0);
1602 ClearPageUptodate(page
);
1605 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1606 pagevec_release(&pvec
);
1611 static void ext4_print_free_blocks(struct inode
*inode
)
1613 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1614 struct super_block
*sb
= inode
->i_sb
;
1615 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1617 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1618 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1619 ext4_count_free_clusters(sb
)));
1620 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1621 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1622 (long long) EXT4_C2B(EXT4_SB(sb
),
1623 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1624 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1625 (long long) EXT4_C2B(EXT4_SB(sb
),
1626 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1627 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1628 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1629 ei
->i_reserved_data_blocks
);
1630 ext4_msg(sb
, KERN_CRIT
, "i_reserved_meta_blocks=%u",
1631 ei
->i_reserved_meta_blocks
);
1632 ext4_msg(sb
, KERN_CRIT
, "i_allocated_meta_blocks=%u",
1633 ei
->i_allocated_meta_blocks
);
1638 * mpage_da_map_and_submit - go through given space, map them
1639 * if necessary, and then submit them for I/O
1641 * @mpd - bh describing space
1643 * The function skips space we know is already mapped to disk blocks.
1646 static void mpage_da_map_and_submit(struct mpage_da_data
*mpd
)
1648 int err
, blks
, get_blocks_flags
;
1649 struct ext4_map_blocks map
, *mapp
= NULL
;
1650 sector_t next
= mpd
->b_blocknr
;
1651 unsigned max_blocks
= mpd
->b_size
>> mpd
->inode
->i_blkbits
;
1652 loff_t disksize
= EXT4_I(mpd
->inode
)->i_disksize
;
1653 handle_t
*handle
= NULL
;
1656 * If the blocks are mapped already, or we couldn't accumulate
1657 * any blocks, then proceed immediately to the submission stage.
1659 if ((mpd
->b_size
== 0) ||
1660 ((mpd
->b_state
& (1 << BH_Mapped
)) &&
1661 !(mpd
->b_state
& (1 << BH_Delay
)) &&
1662 !(mpd
->b_state
& (1 << BH_Unwritten
))))
1665 handle
= ext4_journal_current_handle();
1669 * Call ext4_map_blocks() to allocate any delayed allocation
1670 * blocks, or to convert an uninitialized extent to be
1671 * initialized (in the case where we have written into
1672 * one or more preallocated blocks).
1674 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to
1675 * indicate that we are on the delayed allocation path. This
1676 * affects functions in many different parts of the allocation
1677 * call path. This flag exists primarily because we don't
1678 * want to change *many* call functions, so ext4_map_blocks()
1679 * will set the EXT4_STATE_DELALLOC_RESERVED flag once the
1680 * inode's allocation semaphore is taken.
1682 * If the blocks in questions were delalloc blocks, set
1683 * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
1684 * variables are updated after the blocks have been allocated.
1687 map
.m_len
= max_blocks
;
1689 * We're in delalloc path and it is possible that we're going to
1690 * need more metadata blocks than previously reserved. However
1691 * we must not fail because we're in writeback and there is
1692 * nothing we can do about it so it might result in data loss.
1693 * So use reserved blocks to allocate metadata if possible.
1695 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
1696 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
1697 if (ext4_should_dioread_nolock(mpd
->inode
))
1698 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
1699 if (mpd
->b_state
& (1 << BH_Delay
))
1700 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
1703 blks
= ext4_map_blocks(handle
, mpd
->inode
, &map
, get_blocks_flags
);
1705 struct super_block
*sb
= mpd
->inode
->i_sb
;
1709 * If get block returns EAGAIN or ENOSPC and there
1710 * appears to be free blocks we will just let
1711 * mpage_da_submit_io() unlock all of the pages.
1716 if (err
== -ENOSPC
&& ext4_count_free_clusters(sb
)) {
1722 * get block failure will cause us to loop in
1723 * writepages, because a_ops->writepage won't be able
1724 * to make progress. The page will be redirtied by
1725 * writepage and writepages will again try to write
1728 if (!(EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
1729 ext4_msg(sb
, KERN_CRIT
,
1730 "delayed block allocation failed for inode %lu "
1731 "at logical offset %llu with max blocks %zd "
1732 "with error %d", mpd
->inode
->i_ino
,
1733 (unsigned long long) next
,
1734 mpd
->b_size
>> mpd
->inode
->i_blkbits
, err
);
1735 ext4_msg(sb
, KERN_CRIT
,
1736 "This should not happen!! Data will be lost");
1738 ext4_print_free_blocks(mpd
->inode
);
1740 /* invalidate all the pages */
1741 ext4_da_block_invalidatepages(mpd
);
1743 /* Mark this page range as having been completed */
1750 if (map
.m_flags
& EXT4_MAP_NEW
) {
1751 struct block_device
*bdev
= mpd
->inode
->i_sb
->s_bdev
;
1754 for (i
= 0; i
< map
.m_len
; i
++)
1755 unmap_underlying_metadata(bdev
, map
.m_pblk
+ i
);
1759 * Update on-disk size along with block allocation.
1761 disksize
= ((loff_t
) next
+ blks
) << mpd
->inode
->i_blkbits
;
1762 if (disksize
> i_size_read(mpd
->inode
))
1763 disksize
= i_size_read(mpd
->inode
);
1764 if (disksize
> EXT4_I(mpd
->inode
)->i_disksize
) {
1765 ext4_update_i_disksize(mpd
->inode
, disksize
);
1766 err
= ext4_mark_inode_dirty(handle
, mpd
->inode
);
1768 ext4_error(mpd
->inode
->i_sb
,
1769 "Failed to mark inode %lu dirty",
1774 mpage_da_submit_io(mpd
, mapp
);
1778 #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
1779 (1 << BH_Delay) | (1 << BH_Unwritten))
1782 * mpage_add_bh_to_extent - try to add one more block to extent of blocks
1784 * @mpd->lbh - extent of blocks
1785 * @logical - logical number of the block in the file
1786 * @b_state - b_state of the buffer head added
1788 * the function is used to collect contig. blocks in same state
1790 static void mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, sector_t logical
,
1791 unsigned long b_state
)
1794 int blkbits
= mpd
->inode
->i_blkbits
;
1795 int nrblocks
= mpd
->b_size
>> blkbits
;
1798 * XXX Don't go larger than mballoc is willing to allocate
1799 * This is a stopgap solution. We eventually need to fold
1800 * mpage_da_submit_io() into this function and then call
1801 * ext4_map_blocks() multiple times in a loop
1803 if (nrblocks
>= (8*1024*1024 >> blkbits
))
1806 /* check if the reserved journal credits might overflow */
1807 if (!ext4_test_inode_flag(mpd
->inode
, EXT4_INODE_EXTENTS
)) {
1808 if (nrblocks
>= EXT4_MAX_TRANS_DATA
) {
1810 * With non-extent format we are limited by the journal
1811 * credit available. Total credit needed to insert
1812 * nrblocks contiguous blocks is dependent on the
1813 * nrblocks. So limit nrblocks.
1819 * First block in the extent
1821 if (mpd
->b_size
== 0) {
1822 mpd
->b_blocknr
= logical
;
1823 mpd
->b_size
= 1 << blkbits
;
1824 mpd
->b_state
= b_state
& BH_FLAGS
;
1828 next
= mpd
->b_blocknr
+ nrblocks
;
1830 * Can we merge the block to our big extent?
1832 if (logical
== next
&& (b_state
& BH_FLAGS
) == mpd
->b_state
) {
1833 mpd
->b_size
+= 1 << blkbits
;
1839 * We couldn't merge the block to our extent, so we
1840 * need to flush current extent and start new one
1842 mpage_da_map_and_submit(mpd
);
1846 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1848 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1852 * This function is grabs code from the very beginning of
1853 * ext4_map_blocks, but assumes that the caller is from delayed write
1854 * time. This function looks up the requested blocks and sets the
1855 * buffer delay bit under the protection of i_data_sem.
1857 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1858 struct ext4_map_blocks
*map
,
1859 struct buffer_head
*bh
)
1861 struct extent_status es
;
1863 sector_t invalid_block
= ~((sector_t
) 0xffff);
1864 #ifdef ES_AGGRESSIVE_TEST
1865 struct ext4_map_blocks orig_map
;
1867 memcpy(&orig_map
, map
, sizeof(*map
));
1870 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1874 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1875 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1876 (unsigned long) map
->m_lblk
);
1878 /* Lookup extent status tree firstly */
1879 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1881 if (ext4_es_is_hole(&es
)) {
1883 down_read((&EXT4_I(inode
)->i_data_sem
));
1888 * Delayed extent could be allocated by fallocate.
1889 * So we need to check it.
1891 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1892 map_bh(bh
, inode
->i_sb
, invalid_block
);
1894 set_buffer_delay(bh
);
1898 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1899 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1900 if (retval
> map
->m_len
)
1901 retval
= map
->m_len
;
1902 map
->m_len
= retval
;
1903 if (ext4_es_is_written(&es
))
1904 map
->m_flags
|= EXT4_MAP_MAPPED
;
1905 else if (ext4_es_is_unwritten(&es
))
1906 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1910 #ifdef ES_AGGRESSIVE_TEST
1911 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1917 * Try to see if we can get the block without requesting a new
1918 * file system block.
1920 down_read((&EXT4_I(inode
)->i_data_sem
));
1921 if (ext4_has_inline_data(inode
)) {
1923 * We will soon create blocks for this page, and let
1924 * us pretend as if the blocks aren't allocated yet.
1925 * In case of clusters, we have to handle the work
1926 * of mapping from cluster so that the reserved space
1927 * is calculated properly.
1929 if ((EXT4_SB(inode
->i_sb
)->s_cluster_ratio
> 1) &&
1930 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
1931 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
1933 } else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1934 retval
= ext4_ext_map_blocks(NULL
, inode
, map
,
1935 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1937 retval
= ext4_ind_map_blocks(NULL
, inode
, map
,
1938 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1944 * XXX: __block_prepare_write() unmaps passed block,
1948 * If the block was allocated from previously allocated cluster,
1949 * then we don't need to reserve it again. However we still need
1950 * to reserve metadata for every block we're going to write.
1952 if (!(map
->m_flags
& EXT4_MAP_FROM_CLUSTER
)) {
1953 ret
= ext4_da_reserve_space(inode
, iblock
);
1955 /* not enough space to reserve */
1960 ret
= ext4_da_reserve_metadata(inode
, iblock
);
1962 /* not enough space to reserve */
1968 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1969 ~0, EXTENT_STATUS_DELAYED
);
1975 /* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
1976 * and it should not appear on the bh->b_state.
1978 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
1980 map_bh(bh
, inode
->i_sb
, invalid_block
);
1982 set_buffer_delay(bh
);
1983 } else if (retval
> 0) {
1985 unsigned long long status
;
1987 #ifdef ES_AGGRESSIVE_TEST
1988 if (retval
!= map
->m_len
) {
1989 printk("ES len assertation failed for inode: %lu "
1990 "retval %d != map->m_len %d "
1991 "in %s (lookup)\n", inode
->i_ino
, retval
,
1992 map
->m_len
, __func__
);
1996 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
1997 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
1998 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1999 map
->m_pblk
, status
);
2005 up_read((&EXT4_I(inode
)->i_data_sem
));
2011 * This is a special get_blocks_t callback which is used by
2012 * ext4_da_write_begin(). It will either return mapped block or
2013 * reserve space for a single block.
2015 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
2016 * We also have b_blocknr = -1 and b_bdev initialized properly
2018 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
2019 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
2020 * initialized properly.
2022 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
2023 struct buffer_head
*bh
, int create
)
2025 struct ext4_map_blocks map
;
2028 BUG_ON(create
== 0);
2029 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
2031 map
.m_lblk
= iblock
;
2035 * first, we need to know whether the block is allocated already
2036 * preallocated blocks are unmapped but should treated
2037 * the same as allocated blocks.
2039 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
2043 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
2044 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
2046 if (buffer_unwritten(bh
)) {
2047 /* A delayed write to unwritten bh should be marked
2048 * new and mapped. Mapped ensures that we don't do
2049 * get_block multiple times when we write to the same
2050 * offset and new ensures that we do proper zero out
2051 * for partial write.
2054 set_buffer_mapped(bh
);
2059 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
2065 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
2071 static int __ext4_journalled_writepage(struct page
*page
,
2074 struct address_space
*mapping
= page
->mapping
;
2075 struct inode
*inode
= mapping
->host
;
2076 struct buffer_head
*page_bufs
= NULL
;
2077 handle_t
*handle
= NULL
;
2078 int ret
= 0, err
= 0;
2079 int inline_data
= ext4_has_inline_data(inode
);
2080 struct buffer_head
*inode_bh
= NULL
;
2082 ClearPageChecked(page
);
2085 BUG_ON(page
->index
!= 0);
2086 BUG_ON(len
> ext4_get_max_inline_size(inode
));
2087 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
2088 if (inode_bh
== NULL
)
2091 page_bufs
= page_buffers(page
);
2096 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
2099 /* As soon as we unlock the page, it can go away, but we have
2100 * references to buffers so we are safe */
2103 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2104 ext4_writepage_trans_blocks(inode
));
2105 if (IS_ERR(handle
)) {
2106 ret
= PTR_ERR(handle
);
2110 BUG_ON(!ext4_handle_valid(handle
));
2113 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
2115 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
2118 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
2119 do_journal_get_write_access
);
2121 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
2126 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
2127 err
= ext4_journal_stop(handle
);
2131 if (!ext4_has_inline_data(inode
))
2132 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
2134 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
2141 * Note that we don't need to start a transaction unless we're journaling data
2142 * because we should have holes filled from ext4_page_mkwrite(). We even don't
2143 * need to file the inode to the transaction's list in ordered mode because if
2144 * we are writing back data added by write(), the inode is already there and if
2145 * we are writing back data modified via mmap(), no one guarantees in which
2146 * transaction the data will hit the disk. In case we are journaling data, we
2147 * cannot start transaction directly because transaction start ranks above page
2148 * lock so we have to do some magic.
2150 * This function can get called via...
2151 * - ext4_da_writepages after taking page lock (have journal handle)
2152 * - journal_submit_inode_data_buffers (no journal handle)
2153 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
2154 * - grab_page_cache when doing write_begin (have journal handle)
2156 * We don't do any block allocation in this function. If we have page with
2157 * multiple blocks we need to write those buffer_heads that are mapped. This
2158 * is important for mmaped based write. So if we do with blocksize 1K
2159 * truncate(f, 1024);
2160 * a = mmap(f, 0, 4096);
2162 * truncate(f, 4096);
2163 * we have in the page first buffer_head mapped via page_mkwrite call back
2164 * but other buffer_heads would be unmapped but dirty (dirty done via the
2165 * do_wp_page). So writepage should write the first block. If we modify
2166 * the mmap area beyond 1024 we will again get a page_fault and the
2167 * page_mkwrite callback will do the block allocation and mark the
2168 * buffer_heads mapped.
2170 * We redirty the page if we have any buffer_heads that is either delay or
2171 * unwritten in the page.
2173 * We can get recursively called as show below.
2175 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
2178 * But since we don't do any block allocation we should not deadlock.
2179 * Page also have the dirty flag cleared so we don't get recurive page_lock.
2181 static int ext4_writepage(struct page
*page
,
2182 struct writeback_control
*wbc
)
2187 struct buffer_head
*page_bufs
= NULL
;
2188 struct inode
*inode
= page
->mapping
->host
;
2189 struct ext4_io_submit io_submit
;
2191 trace_ext4_writepage(page
);
2192 size
= i_size_read(inode
);
2193 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
2194 len
= size
& ~PAGE_CACHE_MASK
;
2196 len
= PAGE_CACHE_SIZE
;
2198 page_bufs
= page_buffers(page
);
2200 * We cannot do block allocation or other extent handling in this
2201 * function. If there are buffers needing that, we have to redirty
2202 * the page. But we may reach here when we do a journal commit via
2203 * journal_submit_inode_data_buffers() and in that case we must write
2204 * allocated buffers to achieve data=ordered mode guarantees.
2206 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
2207 ext4_bh_delay_or_unwritten
)) {
2208 redirty_page_for_writepage(wbc
, page
);
2209 if (current
->flags
& PF_MEMALLOC
) {
2211 * For memory cleaning there's no point in writing only
2212 * some buffers. So just bail out. Warn if we came here
2213 * from direct reclaim.
2215 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
2222 if (PageChecked(page
) && ext4_should_journal_data(inode
))
2224 * It's mmapped pagecache. Add buffers and journal it. There
2225 * doesn't seem much point in redirtying the page here.
2227 return __ext4_journalled_writepage(page
, len
);
2229 memset(&io_submit
, 0, sizeof(io_submit
));
2230 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
);
2231 ext4_io_submit(&io_submit
);
2236 * This is called via ext4_da_writepages() to
2237 * calculate the total number of credits to reserve to fit
2238 * a single extent allocation into a single transaction,
2239 * ext4_da_writpeages() will loop calling this before
2240 * the block allocation.
2243 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2245 int max_blocks
= EXT4_I(inode
)->i_reserved_data_blocks
;
2248 * With non-extent format the journal credit needed to
2249 * insert nrblocks contiguous block is dependent on
2250 * number of contiguous block. So we will limit
2251 * number of contiguous block to a sane value
2253 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) &&
2254 (max_blocks
> EXT4_MAX_TRANS_DATA
))
2255 max_blocks
= EXT4_MAX_TRANS_DATA
;
2257 return ext4_chunk_trans_blocks(inode
, max_blocks
);
2261 * write_cache_pages_da - walk the list of dirty pages of the given
2262 * address space and accumulate pages that need writing, and call
2263 * mpage_da_map_and_submit to map a single contiguous memory region
2264 * and then write them.
2266 static int write_cache_pages_da(handle_t
*handle
,
2267 struct address_space
*mapping
,
2268 struct writeback_control
*wbc
,
2269 struct mpage_da_data
*mpd
,
2270 pgoff_t
*done_index
)
2272 struct buffer_head
*bh
, *head
;
2273 struct inode
*inode
= mapping
->host
;
2274 struct pagevec pvec
;
2275 unsigned int nr_pages
;
2278 long nr_to_write
= wbc
->nr_to_write
;
2279 int i
, tag
, ret
= 0;
2281 memset(mpd
, 0, sizeof(struct mpage_da_data
));
2284 pagevec_init(&pvec
, 0);
2285 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2286 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2288 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2289 tag
= PAGECACHE_TAG_TOWRITE
;
2291 tag
= PAGECACHE_TAG_DIRTY
;
2293 *done_index
= index
;
2294 while (index
<= end
) {
2295 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2296 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2300 for (i
= 0; i
< nr_pages
; i
++) {
2301 struct page
*page
= pvec
.pages
[i
];
2304 * At this point, the page may be truncated or
2305 * invalidated (changing page->mapping to NULL), or
2306 * even swizzled back from swapper_space to tmpfs file
2307 * mapping. However, page->index will not change
2308 * because we have a reference on the page.
2310 if (page
->index
> end
)
2313 *done_index
= page
->index
+ 1;
2316 * If we can't merge this page, and we have
2317 * accumulated an contiguous region, write it
2319 if ((mpd
->next_page
!= page
->index
) &&
2320 (mpd
->next_page
!= mpd
->first_page
)) {
2321 mpage_da_map_and_submit(mpd
);
2322 goto ret_extent_tail
;
2328 * If the page is no longer dirty, or its
2329 * mapping no longer corresponds to inode we
2330 * are writing (which means it has been
2331 * truncated or invalidated), or the page is
2332 * already under writeback and we are not
2333 * doing a data integrity writeback, skip the page
2335 if (!PageDirty(page
) ||
2336 (PageWriteback(page
) &&
2337 (wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2338 unlikely(page
->mapping
!= mapping
)) {
2343 wait_on_page_writeback(page
);
2344 BUG_ON(PageWriteback(page
));
2347 * If we have inline data and arrive here, it means that
2348 * we will soon create the block for the 1st page, so
2349 * we'd better clear the inline data here.
2351 if (ext4_has_inline_data(inode
)) {
2352 BUG_ON(ext4_test_inode_state(inode
,
2353 EXT4_STATE_MAY_INLINE_DATA
));
2354 ext4_destroy_inline_data(handle
, inode
);
2357 if (mpd
->next_page
!= page
->index
)
2358 mpd
->first_page
= page
->index
;
2359 mpd
->next_page
= page
->index
+ 1;
2360 logical
= (sector_t
) page
->index
<<
2361 (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
2363 /* Add all dirty buffers to mpd */
2364 head
= page_buffers(page
);
2367 BUG_ON(buffer_locked(bh
));
2369 * We need to try to allocate unmapped blocks
2370 * in the same page. Otherwise we won't make
2371 * progress with the page in ext4_writepage
2373 if (ext4_bh_delay_or_unwritten(NULL
, bh
)) {
2374 mpage_add_bh_to_extent(mpd
, logical
,
2377 goto ret_extent_tail
;
2378 } else if (buffer_dirty(bh
) &&
2379 buffer_mapped(bh
)) {
2381 * mapped dirty buffer. We need to
2382 * update the b_state because we look
2383 * at b_state in mpage_da_map_blocks.
2384 * We don't update b_size because if we
2385 * find an unmapped buffer_head later
2386 * we need to use the b_state flag of
2389 if (mpd
->b_size
== 0)
2391 bh
->b_state
& BH_FLAGS
;
2394 } while ((bh
= bh
->b_this_page
) != head
);
2396 if (nr_to_write
> 0) {
2398 if (nr_to_write
== 0 &&
2399 wbc
->sync_mode
== WB_SYNC_NONE
)
2401 * We stop writing back only if we are
2402 * not doing integrity sync. In case of
2403 * integrity sync we have to keep going
2404 * because someone may be concurrently
2405 * dirtying pages, and we might have
2406 * synced a lot of newly appeared dirty
2407 * pages, but have not synced all of the
2413 pagevec_release(&pvec
);
2418 ret
= MPAGE_DA_EXTENT_TAIL
;
2420 pagevec_release(&pvec
);
2426 static int ext4_da_writepages(struct address_space
*mapping
,
2427 struct writeback_control
*wbc
)
2430 int range_whole
= 0;
2431 handle_t
*handle
= NULL
;
2432 struct mpage_da_data mpd
;
2433 struct inode
*inode
= mapping
->host
;
2434 int pages_written
= 0;
2435 unsigned int max_pages
;
2436 int range_cyclic
, cycled
= 1, io_done
= 0;
2437 int needed_blocks
, ret
= 0;
2438 long desired_nr_to_write
, nr_to_writebump
= 0;
2439 loff_t range_start
= wbc
->range_start
;
2440 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2441 pgoff_t done_index
= 0;
2443 struct blk_plug plug
;
2445 trace_ext4_da_writepages(inode
, wbc
);
2448 * No pages to write? This is mainly a kludge to avoid starting
2449 * a transaction for special inodes like journal inode on last iput()
2450 * because that could violate lock ordering on umount
2452 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2456 * If the filesystem has aborted, it is read-only, so return
2457 * right away instead of dumping stack traces later on that
2458 * will obscure the real source of the problem. We test
2459 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2460 * the latter could be true if the filesystem is mounted
2461 * read-only, and in that case, ext4_da_writepages should
2462 * *never* be called, so if that ever happens, we would want
2465 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
))
2468 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2471 range_cyclic
= wbc
->range_cyclic
;
2472 if (wbc
->range_cyclic
) {
2473 index
= mapping
->writeback_index
;
2476 wbc
->range_start
= index
<< PAGE_CACHE_SHIFT
;
2477 wbc
->range_end
= LLONG_MAX
;
2478 wbc
->range_cyclic
= 0;
2481 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2482 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2486 * This works around two forms of stupidity. The first is in
2487 * the writeback code, which caps the maximum number of pages
2488 * written to be 1024 pages. This is wrong on multiple
2489 * levels; different architectues have a different page size,
2490 * which changes the maximum amount of data which gets
2491 * written. Secondly, 4 megabytes is way too small. XFS
2492 * forces this value to be 16 megabytes by multiplying
2493 * nr_to_write parameter by four, and then relies on its
2494 * allocator to allocate larger extents to make them
2495 * contiguous. Unfortunately this brings us to the second
2496 * stupidity, which is that ext4's mballoc code only allocates
2497 * at most 2048 blocks. So we force contiguous writes up to
2498 * the number of dirty blocks in the inode, or
2499 * sbi->max_writeback_mb_bump whichever is smaller.
2501 max_pages
= sbi
->s_max_writeback_mb_bump
<< (20 - PAGE_CACHE_SHIFT
);
2502 if (!range_cyclic
&& range_whole
) {
2503 if (wbc
->nr_to_write
== LONG_MAX
)
2504 desired_nr_to_write
= wbc
->nr_to_write
;
2506 desired_nr_to_write
= wbc
->nr_to_write
* 8;
2508 desired_nr_to_write
= ext4_num_dirty_pages(inode
, index
,
2510 if (desired_nr_to_write
> max_pages
)
2511 desired_nr_to_write
= max_pages
;
2513 if (wbc
->nr_to_write
< desired_nr_to_write
) {
2514 nr_to_writebump
= desired_nr_to_write
- wbc
->nr_to_write
;
2515 wbc
->nr_to_write
= desired_nr_to_write
;
2519 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2520 tag_pages_for_writeback(mapping
, index
, end
);
2522 blk_start_plug(&plug
);
2523 while (!ret
&& wbc
->nr_to_write
> 0) {
2526 * we insert one extent at a time. So we need
2527 * credit needed for single extent allocation.
2528 * journalled mode is currently not supported
2531 BUG_ON(ext4_should_journal_data(inode
));
2532 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2534 /* start a new transaction*/
2535 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2537 if (IS_ERR(handle
)) {
2538 ret
= PTR_ERR(handle
);
2539 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2540 "%ld pages, ino %lu; err %d", __func__
,
2541 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2542 blk_finish_plug(&plug
);
2543 goto out_writepages
;
2547 * Now call write_cache_pages_da() to find the next
2548 * contiguous region of logical blocks that need
2549 * blocks to be allocated by ext4 and submit them.
2551 ret
= write_cache_pages_da(handle
, mapping
,
2552 wbc
, &mpd
, &done_index
);
2554 * If we have a contiguous extent of pages and we
2555 * haven't done the I/O yet, map the blocks and submit
2558 if (!mpd
.io_done
&& mpd
.next_page
!= mpd
.first_page
) {
2559 mpage_da_map_and_submit(&mpd
);
2560 ret
= MPAGE_DA_EXTENT_TAIL
;
2562 trace_ext4_da_write_pages(inode
, &mpd
);
2563 wbc
->nr_to_write
-= mpd
.pages_written
;
2565 ext4_journal_stop(handle
);
2567 if ((mpd
.retval
== -ENOSPC
) && sbi
->s_journal
) {
2568 /* commit the transaction which would
2569 * free blocks released in the transaction
2572 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2574 } else if (ret
== MPAGE_DA_EXTENT_TAIL
) {
2576 * Got one extent now try with rest of the pages.
2577 * If mpd.retval is set -EIO, journal is aborted.
2578 * So we don't need to write any more.
2580 pages_written
+= mpd
.pages_written
;
2583 } else if (wbc
->nr_to_write
)
2585 * There is no more writeout needed
2586 * or we requested for a noblocking writeout
2587 * and we found the device congested
2591 blk_finish_plug(&plug
);
2592 if (!io_done
&& !cycled
) {
2595 wbc
->range_start
= index
<< PAGE_CACHE_SHIFT
;
2596 wbc
->range_end
= mapping
->writeback_index
- 1;
2601 wbc
->range_cyclic
= range_cyclic
;
2602 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2604 * set the writeback_index so that range_cyclic
2605 * mode will write it back later
2607 mapping
->writeback_index
= done_index
;
2610 wbc
->nr_to_write
-= nr_to_writebump
;
2611 wbc
->range_start
= range_start
;
2612 trace_ext4_da_writepages_result(inode
, wbc
, ret
, pages_written
);
2616 static int ext4_nonda_switch(struct super_block
*sb
)
2618 s64 free_clusters
, dirty_clusters
;
2619 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2622 * switch to non delalloc mode if we are running low
2623 * on free block. The free block accounting via percpu
2624 * counters can get slightly wrong with percpu_counter_batch getting
2625 * accumulated on each CPU without updating global counters
2626 * Delalloc need an accurate free block accounting. So switch
2627 * to non delalloc when we are near to error range.
2630 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2632 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2634 * Start pushing delalloc when 1/2 of free blocks are dirty.
2636 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2637 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2639 if (2 * free_clusters
< 3 * dirty_clusters
||
2640 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2642 * free block count is less than 150% of dirty blocks
2643 * or free blocks is less than watermark
2650 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2651 loff_t pos
, unsigned len
, unsigned flags
,
2652 struct page
**pagep
, void **fsdata
)
2654 int ret
, retries
= 0;
2657 struct inode
*inode
= mapping
->host
;
2660 index
= pos
>> PAGE_CACHE_SHIFT
;
2662 if (ext4_nonda_switch(inode
->i_sb
)) {
2663 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2664 return ext4_write_begin(file
, mapping
, pos
,
2665 len
, flags
, pagep
, fsdata
);
2667 *fsdata
= (void *)0;
2668 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2670 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2671 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2681 * grab_cache_page_write_begin() can take a long time if the
2682 * system is thrashing due to memory pressure, or if the page
2683 * is being written back. So grab it first before we start
2684 * the transaction handle. This also allows us to allocate
2685 * the page (if needed) without using GFP_NOFS.
2688 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2694 * With delayed allocation, we don't log the i_disksize update
2695 * if there is delayed block allocation. But we still need
2696 * to journalling the i_disksize update if writes to the end
2697 * of file which has an already mapped buffer.
2700 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, 1);
2701 if (IS_ERR(handle
)) {
2702 page_cache_release(page
);
2703 return PTR_ERR(handle
);
2707 if (page
->mapping
!= mapping
) {
2708 /* The page got truncated from under us */
2710 page_cache_release(page
);
2711 ext4_journal_stop(handle
);
2714 /* In case writeback began while the page was unlocked */
2715 wait_on_page_writeback(page
);
2717 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2720 ext4_journal_stop(handle
);
2722 * block_write_begin may have instantiated a few blocks
2723 * outside i_size. Trim these off again. Don't need
2724 * i_size_read because we hold i_mutex.
2726 if (pos
+ len
> inode
->i_size
)
2727 ext4_truncate_failed_write(inode
);
2729 if (ret
== -ENOSPC
&&
2730 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2733 page_cache_release(page
);
2742 * Check if we should update i_disksize
2743 * when write to the end of file but not require block allocation
2745 static int ext4_da_should_update_i_disksize(struct page
*page
,
2746 unsigned long offset
)
2748 struct buffer_head
*bh
;
2749 struct inode
*inode
= page
->mapping
->host
;
2753 bh
= page_buffers(page
);
2754 idx
= offset
>> inode
->i_blkbits
;
2756 for (i
= 0; i
< idx
; i
++)
2757 bh
= bh
->b_this_page
;
2759 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2764 static int ext4_da_write_end(struct file
*file
,
2765 struct address_space
*mapping
,
2766 loff_t pos
, unsigned len
, unsigned copied
,
2767 struct page
*page
, void *fsdata
)
2769 struct inode
*inode
= mapping
->host
;
2771 handle_t
*handle
= ext4_journal_current_handle();
2773 unsigned long start
, end
;
2774 int write_mode
= (int)(unsigned long)fsdata
;
2776 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2777 return ext4_write_end(file
, mapping
, pos
,
2778 len
, copied
, page
, fsdata
);
2780 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2781 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2782 end
= start
+ copied
- 1;
2785 * generic_write_end() will run mark_inode_dirty() if i_size
2786 * changes. So let's piggyback the i_disksize mark_inode_dirty
2789 new_i_size
= pos
+ copied
;
2790 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2791 if (ext4_has_inline_data(inode
) ||
2792 ext4_da_should_update_i_disksize(page
, end
)) {
2793 down_write(&EXT4_I(inode
)->i_data_sem
);
2794 if (new_i_size
> EXT4_I(inode
)->i_disksize
)
2795 EXT4_I(inode
)->i_disksize
= new_i_size
;
2796 up_write(&EXT4_I(inode
)->i_data_sem
);
2797 /* We need to mark inode dirty even if
2798 * new_i_size is less that inode->i_size
2799 * bu greater than i_disksize.(hint delalloc)
2801 ext4_mark_inode_dirty(handle
, inode
);
2805 if (write_mode
!= CONVERT_INLINE_DATA
&&
2806 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2807 ext4_has_inline_data(inode
))
2808 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2811 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2817 ret2
= ext4_journal_stop(handle
);
2821 return ret
? ret
: copied
;
2824 static void ext4_da_invalidatepage(struct page
*page
, unsigned long offset
)
2827 * Drop reserved blocks
2829 BUG_ON(!PageLocked(page
));
2830 if (!page_has_buffers(page
))
2833 ext4_da_page_release_reservation(page
, offset
);
2836 ext4_invalidatepage(page
, offset
);
2842 * Force all delayed allocation blocks to be allocated for a given inode.
2844 int ext4_alloc_da_blocks(struct inode
*inode
)
2846 trace_ext4_alloc_da_blocks(inode
);
2848 if (!EXT4_I(inode
)->i_reserved_data_blocks
&&
2849 !EXT4_I(inode
)->i_reserved_meta_blocks
)
2853 * We do something simple for now. The filemap_flush() will
2854 * also start triggering a write of the data blocks, which is
2855 * not strictly speaking necessary (and for users of
2856 * laptop_mode, not even desirable). However, to do otherwise
2857 * would require replicating code paths in:
2859 * ext4_da_writepages() ->
2860 * write_cache_pages() ---> (via passed in callback function)
2861 * __mpage_da_writepage() -->
2862 * mpage_add_bh_to_extent()
2863 * mpage_da_map_blocks()
2865 * The problem is that write_cache_pages(), located in
2866 * mm/page-writeback.c, marks pages clean in preparation for
2867 * doing I/O, which is not desirable if we're not planning on
2870 * We could call write_cache_pages(), and then redirty all of
2871 * the pages by calling redirty_page_for_writepage() but that
2872 * would be ugly in the extreme. So instead we would need to
2873 * replicate parts of the code in the above functions,
2874 * simplifying them because we wouldn't actually intend to
2875 * write out the pages, but rather only collect contiguous
2876 * logical block extents, call the multi-block allocator, and
2877 * then update the buffer heads with the block allocations.
2879 * For now, though, we'll cheat by calling filemap_flush(),
2880 * which will map the blocks, and start the I/O, but not
2881 * actually wait for the I/O to complete.
2883 return filemap_flush(inode
->i_mapping
);
2887 * bmap() is special. It gets used by applications such as lilo and by
2888 * the swapper to find the on-disk block of a specific piece of data.
2890 * Naturally, this is dangerous if the block concerned is still in the
2891 * journal. If somebody makes a swapfile on an ext4 data-journaling
2892 * filesystem and enables swap, then they may get a nasty shock when the
2893 * data getting swapped to that swapfile suddenly gets overwritten by
2894 * the original zero's written out previously to the journal and
2895 * awaiting writeback in the kernel's buffer cache.
2897 * So, if we see any bmap calls here on a modified, data-journaled file,
2898 * take extra steps to flush any blocks which might be in the cache.
2900 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2902 struct inode
*inode
= mapping
->host
;
2907 * We can get here for an inline file via the FIBMAP ioctl
2909 if (ext4_has_inline_data(inode
))
2912 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2913 test_opt(inode
->i_sb
, DELALLOC
)) {
2915 * With delalloc we want to sync the file
2916 * so that we can make sure we allocate
2919 filemap_write_and_wait(mapping
);
2922 if (EXT4_JOURNAL(inode
) &&
2923 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2925 * This is a REALLY heavyweight approach, but the use of
2926 * bmap on dirty files is expected to be extremely rare:
2927 * only if we run lilo or swapon on a freshly made file
2928 * do we expect this to happen.
2930 * (bmap requires CAP_SYS_RAWIO so this does not
2931 * represent an unprivileged user DOS attack --- we'd be
2932 * in trouble if mortal users could trigger this path at
2935 * NB. EXT4_STATE_JDATA is not set on files other than
2936 * regular files. If somebody wants to bmap a directory
2937 * or symlink and gets confused because the buffer
2938 * hasn't yet been flushed to disk, they deserve
2939 * everything they get.
2942 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2943 journal
= EXT4_JOURNAL(inode
);
2944 jbd2_journal_lock_updates(journal
);
2945 err
= jbd2_journal_flush(journal
);
2946 jbd2_journal_unlock_updates(journal
);
2952 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2955 static int ext4_readpage(struct file
*file
, struct page
*page
)
2958 struct inode
*inode
= page
->mapping
->host
;
2960 trace_ext4_readpage(page
);
2962 if (ext4_has_inline_data(inode
))
2963 ret
= ext4_readpage_inline(inode
, page
);
2966 return mpage_readpage(page
, ext4_get_block
);
2972 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2973 struct list_head
*pages
, unsigned nr_pages
)
2975 struct inode
*inode
= mapping
->host
;
2977 /* If the file has inline data, no need to do readpages. */
2978 if (ext4_has_inline_data(inode
))
2981 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
2984 static void ext4_invalidatepage(struct page
*page
, unsigned long offset
)
2986 trace_ext4_invalidatepage(page
, offset
);
2988 /* No journalling happens on data buffers when this function is used */
2989 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
2991 block_invalidatepage(page
, offset
);
2994 static int __ext4_journalled_invalidatepage(struct page
*page
,
2995 unsigned long offset
)
2997 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
2999 trace_ext4_journalled_invalidatepage(page
, offset
);
3002 * If it's a full truncate we just forget about the pending dirtying
3005 ClearPageChecked(page
);
3007 return jbd2_journal_invalidatepage(journal
, page
, offset
);
3010 /* Wrapper for aops... */
3011 static void ext4_journalled_invalidatepage(struct page
*page
,
3012 unsigned long offset
)
3014 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
) < 0);
3017 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
3019 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
3021 trace_ext4_releasepage(page
);
3023 /* Page has dirty journalled data -> cannot release */
3024 if (PageChecked(page
))
3027 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
3029 return try_to_free_buffers(page
);
3033 * ext4_get_block used when preparing for a DIO write or buffer write.
3034 * We allocate an uinitialized extent if blocks haven't been allocated.
3035 * The extent will be converted to initialized after the IO is complete.
3037 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
3038 struct buffer_head
*bh_result
, int create
)
3040 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
3041 inode
->i_ino
, create
);
3042 return _ext4_get_block(inode
, iblock
, bh_result
,
3043 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
3046 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
3047 struct buffer_head
*bh_result
, int create
)
3049 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
3050 inode
->i_ino
, create
);
3051 return _ext4_get_block(inode
, iblock
, bh_result
,
3052 EXT4_GET_BLOCKS_NO_LOCK
);
3055 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
3056 ssize_t size
, void *private, int ret
,
3059 struct inode
*inode
= file_inode(iocb
->ki_filp
);
3060 ext4_io_end_t
*io_end
= iocb
->private;
3062 /* if not async direct IO or dio with 0 bytes write, just return */
3063 if (!io_end
|| !size
)
3066 ext_debug("ext4_end_io_dio(): io_end 0x%p "
3067 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
3068 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
3071 iocb
->private = NULL
;
3073 /* if not aio dio with unwritten extents, just free io and return */
3074 if (!(io_end
->flag
& EXT4_IO_END_UNWRITTEN
)) {
3075 ext4_free_io_end(io_end
);
3077 inode_dio_done(inode
);
3079 aio_complete(iocb
, ret
, 0);
3083 io_end
->offset
= offset
;
3084 io_end
->size
= size
;
3086 io_end
->iocb
= iocb
;
3087 io_end
->result
= ret
;
3090 ext4_add_complete_io(io_end
);
3094 * For ext4 extent files, ext4 will do direct-io write to holes,
3095 * preallocated extents, and those write extend the file, no need to
3096 * fall back to buffered IO.
3098 * For holes, we fallocate those blocks, mark them as uninitialized
3099 * If those blocks were preallocated, we mark sure they are split, but
3100 * still keep the range to write as uninitialized.
3102 * The unwritten extents will be converted to written when DIO is completed.
3103 * For async direct IO, since the IO may still pending when return, we
3104 * set up an end_io call back function, which will do the conversion
3105 * when async direct IO completed.
3107 * If the O_DIRECT write will extend the file then add this inode to the
3108 * orphan list. So recovery will truncate it back to the original size
3109 * if the machine crashes during the write.
3112 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
3113 const struct iovec
*iov
, loff_t offset
,
3114 unsigned long nr_segs
)
3116 struct file
*file
= iocb
->ki_filp
;
3117 struct inode
*inode
= file
->f_mapping
->host
;
3119 size_t count
= iov_length(iov
, nr_segs
);
3121 get_block_t
*get_block_func
= NULL
;
3123 loff_t final_size
= offset
+ count
;
3125 /* Use the old path for reads and writes beyond i_size. */
3126 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
3127 return ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3129 BUG_ON(iocb
->private == NULL
);
3131 /* If we do a overwrite dio, i_mutex locking can be released */
3132 overwrite
= *((int *)iocb
->private);
3135 atomic_inc(&inode
->i_dio_count
);
3136 down_read(&EXT4_I(inode
)->i_data_sem
);
3137 mutex_unlock(&inode
->i_mutex
);
3141 * We could direct write to holes and fallocate.
3143 * Allocated blocks to fill the hole are marked as
3144 * uninitialized to prevent parallel buffered read to expose
3145 * the stale data before DIO complete the data IO.
3147 * As to previously fallocated extents, ext4 get_block will
3148 * just simply mark the buffer mapped but still keep the
3149 * extents uninitialized.
3151 * For non AIO case, we will convert those unwritten extents
3152 * to written after return back from blockdev_direct_IO.
3154 * For async DIO, the conversion needs to be deferred when the
3155 * IO is completed. The ext4 end_io callback function will be
3156 * called to take care of the conversion work. Here for async
3157 * case, we allocate an io_end structure to hook to the iocb.
3159 iocb
->private = NULL
;
3160 ext4_inode_aio_set(inode
, NULL
);
3161 if (!is_sync_kiocb(iocb
)) {
3162 ext4_io_end_t
*io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3167 io_end
->flag
|= EXT4_IO_END_DIRECT
;
3168 iocb
->private = io_end
;
3170 * we save the io structure for current async direct
3171 * IO, so that later ext4_map_blocks() could flag the
3172 * io structure whether there is a unwritten extents
3173 * needs to be converted when IO is completed.
3175 ext4_inode_aio_set(inode
, io_end
);
3179 get_block_func
= ext4_get_block_write_nolock
;
3181 get_block_func
= ext4_get_block_write
;
3182 dio_flags
= DIO_LOCKING
;
3184 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3185 inode
->i_sb
->s_bdev
, iov
,
3193 ext4_inode_aio_set(inode
, NULL
);
3195 * The io_end structure takes a reference to the inode, that
3196 * structure needs to be destroyed and the reference to the
3197 * inode need to be dropped, when IO is complete, even with 0
3198 * byte write, or failed.
3200 * In the successful AIO DIO case, the io_end structure will
3201 * be destroyed and the reference to the inode will be dropped
3202 * after the end_io call back function is called.
3204 * In the case there is 0 byte write, or error case, since VFS
3205 * direct IO won't invoke the end_io call back function, we
3206 * need to free the end_io structure here.
3208 if (ret
!= -EIOCBQUEUED
&& ret
<= 0 && iocb
->private) {
3209 ext4_free_io_end(iocb
->private);
3210 iocb
->private = NULL
;
3211 } else if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3212 EXT4_STATE_DIO_UNWRITTEN
)) {
3215 * for non AIO case, since the IO is already
3216 * completed, we could do the conversion right here
3218 err
= ext4_convert_unwritten_extents(inode
,
3222 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3226 /* take i_mutex locking again if we do a ovewrite dio */
3228 inode_dio_done(inode
);
3229 up_read(&EXT4_I(inode
)->i_data_sem
);
3230 mutex_lock(&inode
->i_mutex
);
3236 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3237 const struct iovec
*iov
, loff_t offset
,
3238 unsigned long nr_segs
)
3240 struct file
*file
= iocb
->ki_filp
;
3241 struct inode
*inode
= file
->f_mapping
->host
;
3245 * If we are doing data journalling we don't support O_DIRECT
3247 if (ext4_should_journal_data(inode
))
3250 /* Let buffer I/O handle the inline data case. */
3251 if (ext4_has_inline_data(inode
))
3254 trace_ext4_direct_IO_enter(inode
, offset
, iov_length(iov
, nr_segs
), rw
);
3255 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3256 ret
= ext4_ext_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3258 ret
= ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3259 trace_ext4_direct_IO_exit(inode
, offset
,
3260 iov_length(iov
, nr_segs
), rw
, ret
);
3265 * Pages can be marked dirty completely asynchronously from ext4's journalling
3266 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3267 * much here because ->set_page_dirty is called under VFS locks. The page is
3268 * not necessarily locked.
3270 * We cannot just dirty the page and leave attached buffers clean, because the
3271 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3272 * or jbddirty because all the journalling code will explode.
3274 * So what we do is to mark the page "pending dirty" and next time writepage
3275 * is called, propagate that into the buffers appropriately.
3277 static int ext4_journalled_set_page_dirty(struct page
*page
)
3279 SetPageChecked(page
);
3280 return __set_page_dirty_nobuffers(page
);
3283 static const struct address_space_operations ext4_aops
= {
3284 .readpage
= ext4_readpage
,
3285 .readpages
= ext4_readpages
,
3286 .writepage
= ext4_writepage
,
3287 .write_begin
= ext4_write_begin
,
3288 .write_end
= ext4_write_end
,
3290 .invalidatepage
= ext4_invalidatepage
,
3291 .releasepage
= ext4_releasepage
,
3292 .direct_IO
= ext4_direct_IO
,
3293 .migratepage
= buffer_migrate_page
,
3294 .is_partially_uptodate
= block_is_partially_uptodate
,
3295 .error_remove_page
= generic_error_remove_page
,
3298 static const struct address_space_operations ext4_journalled_aops
= {
3299 .readpage
= ext4_readpage
,
3300 .readpages
= ext4_readpages
,
3301 .writepage
= ext4_writepage
,
3302 .write_begin
= ext4_write_begin
,
3303 .write_end
= ext4_journalled_write_end
,
3304 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3306 .invalidatepage
= ext4_journalled_invalidatepage
,
3307 .releasepage
= ext4_releasepage
,
3308 .direct_IO
= ext4_direct_IO
,
3309 .is_partially_uptodate
= block_is_partially_uptodate
,
3310 .error_remove_page
= generic_error_remove_page
,
3313 static const struct address_space_operations ext4_da_aops
= {
3314 .readpage
= ext4_readpage
,
3315 .readpages
= ext4_readpages
,
3316 .writepage
= ext4_writepage
,
3317 .writepages
= ext4_da_writepages
,
3318 .write_begin
= ext4_da_write_begin
,
3319 .write_end
= ext4_da_write_end
,
3321 .invalidatepage
= ext4_da_invalidatepage
,
3322 .releasepage
= ext4_releasepage
,
3323 .direct_IO
= ext4_direct_IO
,
3324 .migratepage
= buffer_migrate_page
,
3325 .is_partially_uptodate
= block_is_partially_uptodate
,
3326 .error_remove_page
= generic_error_remove_page
,
3329 void ext4_set_aops(struct inode
*inode
)
3331 switch (ext4_inode_journal_mode(inode
)) {
3332 case EXT4_INODE_ORDERED_DATA_MODE
:
3333 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3335 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3336 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3338 case EXT4_INODE_JOURNAL_DATA_MODE
:
3339 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3344 if (test_opt(inode
->i_sb
, DELALLOC
))
3345 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3347 inode
->i_mapping
->a_ops
= &ext4_aops
;
3352 * ext4_discard_partial_page_buffers()
3353 * Wrapper function for ext4_discard_partial_page_buffers_no_lock.
3354 * This function finds and locks the page containing the offset
3355 * "from" and passes it to ext4_discard_partial_page_buffers_no_lock.
3356 * Calling functions that already have the page locked should call
3357 * ext4_discard_partial_page_buffers_no_lock directly.
3359 int ext4_discard_partial_page_buffers(handle_t
*handle
,
3360 struct address_space
*mapping
, loff_t from
,
3361 loff_t length
, int flags
)
3363 struct inode
*inode
= mapping
->host
;
3367 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3368 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3372 err
= ext4_discard_partial_page_buffers_no_lock(handle
, inode
, page
,
3373 from
, length
, flags
);
3376 page_cache_release(page
);
3381 * ext4_discard_partial_page_buffers_no_lock()
3382 * Zeros a page range of length 'length' starting from offset 'from'.
3383 * Buffer heads that correspond to the block aligned regions of the
3384 * zeroed range will be unmapped. Unblock aligned regions
3385 * will have the corresponding buffer head mapped if needed so that
3386 * that region of the page can be updated with the partial zero out.
3388 * This function assumes that the page has already been locked. The
3389 * The range to be discarded must be contained with in the given page.
3390 * If the specified range exceeds the end of the page it will be shortened
3391 * to the end of the page that corresponds to 'from'. This function is
3392 * appropriate for updating a page and it buffer heads to be unmapped and
3393 * zeroed for blocks that have been either released, or are going to be
3396 * handle: The journal handle
3397 * inode: The files inode
3398 * page: A locked page that contains the offset "from"
3399 * from: The starting byte offset (from the beginning of the file)
3400 * to begin discarding
3401 * len: The length of bytes to discard
3402 * flags: Optional flags that may be used:
3404 * EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
3405 * Only zero the regions of the page whose buffer heads
3406 * have already been unmapped. This flag is appropriate
3407 * for updating the contents of a page whose blocks may
3408 * have already been released, and we only want to zero
3409 * out the regions that correspond to those released blocks.
3411 * Returns zero on success or negative on failure.
3413 static int ext4_discard_partial_page_buffers_no_lock(handle_t
*handle
,
3414 struct inode
*inode
, struct page
*page
, loff_t from
,
3415 loff_t length
, int flags
)
3417 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3418 unsigned int offset
= from
& (PAGE_CACHE_SIZE
-1);
3419 unsigned int blocksize
, max
, pos
;
3421 struct buffer_head
*bh
;
3424 blocksize
= inode
->i_sb
->s_blocksize
;
3425 max
= PAGE_CACHE_SIZE
- offset
;
3427 if (index
!= page
->index
)
3431 * correct length if it does not fall between
3432 * 'from' and the end of the page
3434 if (length
> max
|| length
< 0)
3437 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3439 if (!page_has_buffers(page
))
3440 create_empty_buffers(page
, blocksize
, 0);
3442 /* Find the buffer that contains "offset" */
3443 bh
= page_buffers(page
);
3445 while (offset
>= pos
) {
3446 bh
= bh
->b_this_page
;
3452 while (pos
< offset
+ length
) {
3453 unsigned int end_of_block
, range_to_discard
;
3457 /* The length of space left to zero and unmap */
3458 range_to_discard
= offset
+ length
- pos
;
3460 /* The length of space until the end of the block */
3461 end_of_block
= blocksize
- (pos
& (blocksize
-1));
3464 * Do not unmap or zero past end of block
3465 * for this buffer head
3467 if (range_to_discard
> end_of_block
)
3468 range_to_discard
= end_of_block
;
3472 * Skip this buffer head if we are only zeroing unampped
3473 * regions of the page
3475 if (flags
& EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
&&
3479 /* If the range is block aligned, unmap */
3480 if (range_to_discard
== blocksize
) {
3481 clear_buffer_dirty(bh
);
3483 clear_buffer_mapped(bh
);
3484 clear_buffer_req(bh
);
3485 clear_buffer_new(bh
);
3486 clear_buffer_delay(bh
);
3487 clear_buffer_unwritten(bh
);
3488 clear_buffer_uptodate(bh
);
3489 zero_user(page
, pos
, range_to_discard
);
3490 BUFFER_TRACE(bh
, "Buffer discarded");
3495 * If this block is not completely contained in the range
3496 * to be discarded, then it is not going to be released. Because
3497 * we need to keep this block, we need to make sure this part
3498 * of the page is uptodate before we modify it by writeing
3499 * partial zeros on it.
3501 if (!buffer_mapped(bh
)) {
3503 * Buffer head must be mapped before we can read
3506 BUFFER_TRACE(bh
, "unmapped");
3507 ext4_get_block(inode
, iblock
, bh
, 0);
3508 /* unmapped? It's a hole - nothing to do */
3509 if (!buffer_mapped(bh
)) {
3510 BUFFER_TRACE(bh
, "still unmapped");
3515 /* Ok, it's mapped. Make sure it's up-to-date */
3516 if (PageUptodate(page
))
3517 set_buffer_uptodate(bh
);
3519 if (!buffer_uptodate(bh
)) {
3521 ll_rw_block(READ
, 1, &bh
);
3523 /* Uhhuh. Read error. Complain and punt.*/
3524 if (!buffer_uptodate(bh
))
3528 if (ext4_should_journal_data(inode
)) {
3529 BUFFER_TRACE(bh
, "get write access");
3530 err
= ext4_journal_get_write_access(handle
, bh
);
3535 zero_user(page
, pos
, range_to_discard
);
3538 if (ext4_should_journal_data(inode
)) {
3539 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3541 mark_buffer_dirty(bh
);
3543 BUFFER_TRACE(bh
, "Partial buffer zeroed");
3545 bh
= bh
->b_this_page
;
3547 pos
+= range_to_discard
;
3553 int ext4_can_truncate(struct inode
*inode
)
3555 if (S_ISREG(inode
->i_mode
))
3557 if (S_ISDIR(inode
->i_mode
))
3559 if (S_ISLNK(inode
->i_mode
))
3560 return !ext4_inode_is_fast_symlink(inode
);
3565 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3566 * associated with the given offset and length
3568 * @inode: File inode
3569 * @offset: The offset where the hole will begin
3570 * @len: The length of the hole
3572 * Returns: 0 on success or negative on failure
3575 int ext4_punch_hole(struct file
*file
, loff_t offset
, loff_t length
)
3577 struct inode
*inode
= file_inode(file
);
3578 struct super_block
*sb
= inode
->i_sb
;
3579 ext4_lblk_t first_block
, stop_block
;
3580 struct address_space
*mapping
= inode
->i_mapping
;
3581 loff_t first_page
, last_page
, page_len
;
3582 loff_t first_page_offset
, last_page_offset
;
3584 unsigned int credits
;
3587 if (!S_ISREG(inode
->i_mode
))
3590 if (EXT4_SB(sb
)->s_cluster_ratio
> 1) {
3591 /* TODO: Add support for bigalloc file systems */
3595 trace_ext4_punch_hole(inode
, offset
, length
);
3598 * Write out all dirty pages to avoid race conditions
3599 * Then release them.
3601 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3602 ret
= filemap_write_and_wait_range(mapping
, offset
,
3603 offset
+ length
- 1);
3608 mutex_lock(&inode
->i_mutex
);
3609 /* It's not possible punch hole on append only file */
3610 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
)) {
3614 if (IS_SWAPFILE(inode
)) {
3619 /* No need to punch hole beyond i_size */
3620 if (offset
>= inode
->i_size
)
3624 * If the hole extends beyond i_size, set the hole
3625 * to end after the page that contains i_size
3627 if (offset
+ length
> inode
->i_size
) {
3628 length
= inode
->i_size
+
3629 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3633 first_page
= (offset
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
3634 last_page
= (offset
+ length
) >> PAGE_CACHE_SHIFT
;
3636 first_page_offset
= first_page
<< PAGE_CACHE_SHIFT
;
3637 last_page_offset
= last_page
<< PAGE_CACHE_SHIFT
;
3639 /* Now release the pages */
3640 if (last_page_offset
> first_page_offset
) {
3641 truncate_pagecache_range(inode
, first_page_offset
,
3642 last_page_offset
- 1);
3645 /* Wait all existing dio workers, newcomers will block on i_mutex */
3646 ext4_inode_block_unlocked_dio(inode
);
3647 ret
= ext4_flush_unwritten_io(inode
);
3650 inode_dio_wait(inode
);
3652 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3653 credits
= ext4_writepage_trans_blocks(inode
);
3655 credits
= ext4_blocks_for_truncate(inode
);
3656 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3657 if (IS_ERR(handle
)) {
3658 ret
= PTR_ERR(handle
);
3659 ext4_std_error(sb
, ret
);
3664 * Now we need to zero out the non-page-aligned data in the
3665 * pages at the start and tail of the hole, and unmap the
3666 * buffer heads for the block aligned regions of the page that
3667 * were completely zeroed.
3669 if (first_page
> last_page
) {
3671 * If the file space being truncated is contained
3672 * within a page just zero out and unmap the middle of
3675 ret
= ext4_discard_partial_page_buffers(handle
,
3676 mapping
, offset
, length
, 0);
3682 * zero out and unmap the partial page that contains
3683 * the start of the hole
3685 page_len
= first_page_offset
- offset
;
3687 ret
= ext4_discard_partial_page_buffers(handle
, mapping
,
3688 offset
, page_len
, 0);
3694 * zero out and unmap the partial page that contains
3695 * the end of the hole
3697 page_len
= offset
+ length
- last_page_offset
;
3699 ret
= ext4_discard_partial_page_buffers(handle
, mapping
,
3700 last_page_offset
, page_len
, 0);
3707 * If i_size is contained in the last page, we need to
3708 * unmap and zero the partial page after i_size
3710 if (inode
->i_size
>> PAGE_CACHE_SHIFT
== last_page
&&
3711 inode
->i_size
% PAGE_CACHE_SIZE
!= 0) {
3712 page_len
= PAGE_CACHE_SIZE
-
3713 (inode
->i_size
& (PAGE_CACHE_SIZE
- 1));
3716 ret
= ext4_discard_partial_page_buffers(handle
,
3717 mapping
, inode
->i_size
, page_len
, 0);
3724 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3725 EXT4_BLOCK_SIZE_BITS(sb
);
3726 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3728 /* If there are no blocks to remove, return now */
3729 if (first_block
>= stop_block
)
3732 down_write(&EXT4_I(inode
)->i_data_sem
);
3733 ext4_discard_preallocations(inode
);
3735 ret
= ext4_es_remove_extent(inode
, first_block
,
3736 stop_block
- first_block
);
3738 up_write(&EXT4_I(inode
)->i_data_sem
);
3742 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3743 ret
= ext4_ext_remove_space(inode
, first_block
,
3746 ret
= ext4_free_hole_blocks(handle
, inode
, first_block
,
3749 ext4_discard_preallocations(inode
);
3750 up_write(&EXT4_I(inode
)->i_data_sem
);
3752 ext4_handle_sync(handle
);
3753 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3754 ext4_mark_inode_dirty(handle
, inode
);
3756 ext4_journal_stop(handle
);
3758 ext4_inode_resume_unlocked_dio(inode
);
3760 mutex_unlock(&inode
->i_mutex
);
3767 * We block out ext4_get_block() block instantiations across the entire
3768 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3769 * simultaneously on behalf of the same inode.
3771 * As we work through the truncate and commit bits of it to the journal there
3772 * is one core, guiding principle: the file's tree must always be consistent on
3773 * disk. We must be able to restart the truncate after a crash.
3775 * The file's tree may be transiently inconsistent in memory (although it
3776 * probably isn't), but whenever we close off and commit a journal transaction,
3777 * the contents of (the filesystem + the journal) must be consistent and
3778 * restartable. It's pretty simple, really: bottom up, right to left (although
3779 * left-to-right works OK too).
3781 * Note that at recovery time, journal replay occurs *before* the restart of
3782 * truncate against the orphan inode list.
3784 * The committed inode has the new, desired i_size (which is the same as
3785 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3786 * that this inode's truncate did not complete and it will again call
3787 * ext4_truncate() to have another go. So there will be instantiated blocks
3788 * to the right of the truncation point in a crashed ext4 filesystem. But
3789 * that's fine - as long as they are linked from the inode, the post-crash
3790 * ext4_truncate() run will find them and release them.
3792 void ext4_truncate(struct inode
*inode
)
3794 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3795 unsigned int credits
;
3797 struct address_space
*mapping
= inode
->i_mapping
;
3801 * There is a possibility that we're either freeing the inode
3802 * or it completely new indode. In those cases we might not
3803 * have i_mutex locked because it's not necessary.
3805 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3806 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3807 trace_ext4_truncate_enter(inode
);
3809 if (!ext4_can_truncate(inode
))
3812 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3814 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3815 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3817 if (ext4_has_inline_data(inode
)) {
3820 ext4_inline_data_truncate(inode
, &has_inline
);
3826 * finish any pending end_io work so we won't run the risk of
3827 * converting any truncated blocks to initialized later
3829 ext4_flush_unwritten_io(inode
);
3831 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3832 credits
= ext4_writepage_trans_blocks(inode
);
3834 credits
= ext4_blocks_for_truncate(inode
);
3836 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3837 if (IS_ERR(handle
)) {
3838 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3842 if (inode
->i_size
% PAGE_CACHE_SIZE
!= 0) {
3843 page_len
= PAGE_CACHE_SIZE
-
3844 (inode
->i_size
& (PAGE_CACHE_SIZE
- 1));
3846 if (ext4_discard_partial_page_buffers(handle
,
3847 mapping
, inode
->i_size
, page_len
, 0))
3852 * We add the inode to the orphan list, so that if this
3853 * truncate spans multiple transactions, and we crash, we will
3854 * resume the truncate when the filesystem recovers. It also
3855 * marks the inode dirty, to catch the new size.
3857 * Implication: the file must always be in a sane, consistent
3858 * truncatable state while each transaction commits.
3860 if (ext4_orphan_add(handle
, inode
))
3863 down_write(&EXT4_I(inode
)->i_data_sem
);
3865 ext4_discard_preallocations(inode
);
3867 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3868 ext4_ext_truncate(handle
, inode
);
3870 ext4_ind_truncate(handle
, inode
);
3872 up_write(&ei
->i_data_sem
);
3875 ext4_handle_sync(handle
);
3879 * If this was a simple ftruncate() and the file will remain alive,
3880 * then we need to clear up the orphan record which we created above.
3881 * However, if this was a real unlink then we were called by
3882 * ext4_delete_inode(), and we allow that function to clean up the
3883 * orphan info for us.
3886 ext4_orphan_del(handle
, inode
);
3888 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3889 ext4_mark_inode_dirty(handle
, inode
);
3890 ext4_journal_stop(handle
);
3892 trace_ext4_truncate_exit(inode
);
3896 * ext4_get_inode_loc returns with an extra refcount against the inode's
3897 * underlying buffer_head on success. If 'in_mem' is true, we have all
3898 * data in memory that is needed to recreate the on-disk version of this
3901 static int __ext4_get_inode_loc(struct inode
*inode
,
3902 struct ext4_iloc
*iloc
, int in_mem
)
3904 struct ext4_group_desc
*gdp
;
3905 struct buffer_head
*bh
;
3906 struct super_block
*sb
= inode
->i_sb
;
3908 int inodes_per_block
, inode_offset
;
3911 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3914 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3915 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3920 * Figure out the offset within the block group inode table
3922 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3923 inode_offset
= ((inode
->i_ino
- 1) %
3924 EXT4_INODES_PER_GROUP(sb
));
3925 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3926 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3928 bh
= sb_getblk(sb
, block
);
3931 if (!buffer_uptodate(bh
)) {
3935 * If the buffer has the write error flag, we have failed
3936 * to write out another inode in the same block. In this
3937 * case, we don't have to read the block because we may
3938 * read the old inode data successfully.
3940 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3941 set_buffer_uptodate(bh
);
3943 if (buffer_uptodate(bh
)) {
3944 /* someone brought it uptodate while we waited */
3950 * If we have all information of the inode in memory and this
3951 * is the only valid inode in the block, we need not read the
3955 struct buffer_head
*bitmap_bh
;
3958 start
= inode_offset
& ~(inodes_per_block
- 1);
3960 /* Is the inode bitmap in cache? */
3961 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3962 if (unlikely(!bitmap_bh
))
3966 * If the inode bitmap isn't in cache then the
3967 * optimisation may end up performing two reads instead
3968 * of one, so skip it.
3970 if (!buffer_uptodate(bitmap_bh
)) {
3974 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
3975 if (i
== inode_offset
)
3977 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
3981 if (i
== start
+ inodes_per_block
) {
3982 /* all other inodes are free, so skip I/O */
3983 memset(bh
->b_data
, 0, bh
->b_size
);
3984 set_buffer_uptodate(bh
);
3992 * If we need to do any I/O, try to pre-readahead extra
3993 * blocks from the inode table.
3995 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
3996 ext4_fsblk_t b
, end
, table
;
3998 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
4000 table
= ext4_inode_table(sb
, gdp
);
4001 /* s_inode_readahead_blks is always a power of 2 */
4002 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
4006 num
= EXT4_INODES_PER_GROUP(sb
);
4007 if (ext4_has_group_desc_csum(sb
))
4008 num
-= ext4_itable_unused_count(sb
, gdp
);
4009 table
+= num
/ inodes_per_block
;
4013 sb_breadahead(sb
, b
++);
4017 * There are other valid inodes in the buffer, this inode
4018 * has in-inode xattrs, or we don't have this inode in memory.
4019 * Read the block from disk.
4021 trace_ext4_load_inode(inode
);
4023 bh
->b_end_io
= end_buffer_read_sync
;
4024 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
4026 if (!buffer_uptodate(bh
)) {
4027 EXT4_ERROR_INODE_BLOCK(inode
, block
,
4028 "unable to read itable block");
4038 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
4040 /* We have all inode data except xattrs in memory here. */
4041 return __ext4_get_inode_loc(inode
, iloc
,
4042 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
4045 void ext4_set_inode_flags(struct inode
*inode
)
4047 unsigned int flags
= EXT4_I(inode
)->i_flags
;
4048 unsigned int new_fl
= 0;
4050 if (flags
& EXT4_SYNC_FL
)
4052 if (flags
& EXT4_APPEND_FL
)
4054 if (flags
& EXT4_IMMUTABLE_FL
)
4055 new_fl
|= S_IMMUTABLE
;
4056 if (flags
& EXT4_NOATIME_FL
)
4057 new_fl
|= S_NOATIME
;
4058 if (flags
& EXT4_DIRSYNC_FL
)
4059 new_fl
|= S_DIRSYNC
;
4060 set_mask_bits(&inode
->i_flags
,
4061 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
, new_fl
);
4064 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
4065 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
4067 unsigned int vfs_fl
;
4068 unsigned long old_fl
, new_fl
;
4071 vfs_fl
= ei
->vfs_inode
.i_flags
;
4072 old_fl
= ei
->i_flags
;
4073 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
4074 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
4076 if (vfs_fl
& S_SYNC
)
4077 new_fl
|= EXT4_SYNC_FL
;
4078 if (vfs_fl
& S_APPEND
)
4079 new_fl
|= EXT4_APPEND_FL
;
4080 if (vfs_fl
& S_IMMUTABLE
)
4081 new_fl
|= EXT4_IMMUTABLE_FL
;
4082 if (vfs_fl
& S_NOATIME
)
4083 new_fl
|= EXT4_NOATIME_FL
;
4084 if (vfs_fl
& S_DIRSYNC
)
4085 new_fl
|= EXT4_DIRSYNC_FL
;
4086 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
4089 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
4090 struct ext4_inode_info
*ei
)
4093 struct inode
*inode
= &(ei
->vfs_inode
);
4094 struct super_block
*sb
= inode
->i_sb
;
4096 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4097 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
4098 /* we are using combined 48 bit field */
4099 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
4100 le32_to_cpu(raw_inode
->i_blocks_lo
);
4101 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
4102 /* i_blocks represent file system block size */
4103 return i_blocks
<< (inode
->i_blkbits
- 9);
4108 return le32_to_cpu(raw_inode
->i_blocks_lo
);
4112 static inline void ext4_iget_extra_inode(struct inode
*inode
,
4113 struct ext4_inode
*raw_inode
,
4114 struct ext4_inode_info
*ei
)
4116 __le32
*magic
= (void *)raw_inode
+
4117 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
4118 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4119 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
4120 ext4_find_inline_data_nolock(inode
);
4122 EXT4_I(inode
)->i_inline_off
= 0;
4125 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
4127 struct ext4_iloc iloc
;
4128 struct ext4_inode
*raw_inode
;
4129 struct ext4_inode_info
*ei
;
4130 struct inode
*inode
;
4131 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
4137 inode
= iget_locked(sb
, ino
);
4139 return ERR_PTR(-ENOMEM
);
4140 if (!(inode
->i_state
& I_NEW
))
4146 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4149 raw_inode
= ext4_raw_inode(&iloc
);
4151 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4152 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
4153 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
4154 EXT4_INODE_SIZE(inode
->i_sb
)) {
4155 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
4156 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
4157 EXT4_INODE_SIZE(inode
->i_sb
));
4162 ei
->i_extra_isize
= 0;
4164 /* Precompute checksum seed for inode metadata */
4165 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4166 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
)) {
4167 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4169 __le32 inum
= cpu_to_le32(inode
->i_ino
);
4170 __le32 gen
= raw_inode
->i_generation
;
4171 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
4173 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
4177 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
4178 EXT4_ERROR_INODE(inode
, "checksum invalid");
4183 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
4184 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
4185 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
4186 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4187 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
4188 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
4190 i_uid_write(inode
, i_uid
);
4191 i_gid_write(inode
, i_gid
);
4192 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
4194 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
4195 ei
->i_inline_off
= 0;
4196 ei
->i_dir_start_lookup
= 0;
4197 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
4198 /* We now have enough fields to check if the inode was active or not.
4199 * This is needed because nfsd might try to access dead inodes
4200 * the test is that same one that e2fsck uses
4201 * NeilBrown 1999oct15
4203 if (inode
->i_nlink
== 0) {
4204 if ((inode
->i_mode
== 0 ||
4205 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
4206 ino
!= EXT4_BOOT_LOADER_INO
) {
4207 /* this inode is deleted */
4211 /* The only unlinked inodes we let through here have
4212 * valid i_mode and are being read by the orphan
4213 * recovery code: that's fine, we're about to complete
4214 * the process of deleting those.
4215 * OR it is the EXT4_BOOT_LOADER_INO which is
4216 * not initialized on a new filesystem. */
4218 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
4219 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
4220 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
4221 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
4223 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
4224 inode
->i_size
= ext4_isize(raw_inode
);
4225 ei
->i_disksize
= inode
->i_size
;
4227 ei
->i_reserved_quota
= 0;
4229 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4230 ei
->i_block_group
= iloc
.block_group
;
4231 ei
->i_last_alloc_group
= ~0;
4233 * NOTE! The in-memory inode i_data array is in little-endian order
4234 * even on big-endian machines: we do NOT byteswap the block numbers!
4236 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4237 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4238 INIT_LIST_HEAD(&ei
->i_orphan
);
4241 * Set transaction id's of transactions that have to be committed
4242 * to finish f[data]sync. We set them to currently running transaction
4243 * as we cannot be sure that the inode or some of its metadata isn't
4244 * part of the transaction - the inode could have been reclaimed and
4245 * now it is reread from disk.
4248 transaction_t
*transaction
;
4251 read_lock(&journal
->j_state_lock
);
4252 if (journal
->j_running_transaction
)
4253 transaction
= journal
->j_running_transaction
;
4255 transaction
= journal
->j_committing_transaction
;
4257 tid
= transaction
->t_tid
;
4259 tid
= journal
->j_commit_sequence
;
4260 read_unlock(&journal
->j_state_lock
);
4261 ei
->i_sync_tid
= tid
;
4262 ei
->i_datasync_tid
= tid
;
4265 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4266 if (ei
->i_extra_isize
== 0) {
4267 /* The extra space is currently unused. Use it. */
4268 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4269 EXT4_GOOD_OLD_INODE_SIZE
;
4271 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4275 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4276 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4277 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4278 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4280 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4281 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4282 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4284 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4288 if (ei
->i_file_acl
&&
4289 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4290 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4294 } else if (!ext4_has_inline_data(inode
)) {
4295 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4296 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4297 (S_ISLNK(inode
->i_mode
) &&
4298 !ext4_inode_is_fast_symlink(inode
))))
4299 /* Validate extent which is part of inode */
4300 ret
= ext4_ext_check_inode(inode
);
4301 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4302 (S_ISLNK(inode
->i_mode
) &&
4303 !ext4_inode_is_fast_symlink(inode
))) {
4304 /* Validate block references which are part of inode */
4305 ret
= ext4_ind_check_inode(inode
);
4311 if (S_ISREG(inode
->i_mode
)) {
4312 inode
->i_op
= &ext4_file_inode_operations
;
4313 inode
->i_fop
= &ext4_file_operations
;
4314 ext4_set_aops(inode
);
4315 } else if (S_ISDIR(inode
->i_mode
)) {
4316 inode
->i_op
= &ext4_dir_inode_operations
;
4317 inode
->i_fop
= &ext4_dir_operations
;
4318 } else if (S_ISLNK(inode
->i_mode
)) {
4319 if (ext4_inode_is_fast_symlink(inode
)) {
4320 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4321 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4322 sizeof(ei
->i_data
) - 1);
4324 inode
->i_op
= &ext4_symlink_inode_operations
;
4325 ext4_set_aops(inode
);
4327 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4328 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4329 inode
->i_op
= &ext4_special_inode_operations
;
4330 if (raw_inode
->i_block
[0])
4331 init_special_inode(inode
, inode
->i_mode
,
4332 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4334 init_special_inode(inode
, inode
->i_mode
,
4335 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4336 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4337 make_bad_inode(inode
);
4340 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4344 ext4_set_inode_flags(inode
);
4345 unlock_new_inode(inode
);
4351 return ERR_PTR(ret
);
4354 struct inode
*ext4_iget_normal(struct super_block
*sb
, unsigned long ino
)
4356 if (ino
< EXT4_FIRST_INO(sb
) && ino
!= EXT4_ROOT_INO
)
4357 return ERR_PTR(-EIO
);
4358 return ext4_iget(sb
, ino
);
4361 static int ext4_inode_blocks_set(handle_t
*handle
,
4362 struct ext4_inode
*raw_inode
,
4363 struct ext4_inode_info
*ei
)
4365 struct inode
*inode
= &(ei
->vfs_inode
);
4366 u64 i_blocks
= inode
->i_blocks
;
4367 struct super_block
*sb
= inode
->i_sb
;
4369 if (i_blocks
<= ~0U) {
4371 * i_blocks can be represented in a 32 bit variable
4372 * as multiple of 512 bytes
4374 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4375 raw_inode
->i_blocks_high
= 0;
4376 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4379 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4382 if (i_blocks
<= 0xffffffffffffULL
) {
4384 * i_blocks can be represented in a 48 bit variable
4385 * as multiple of 512 bytes
4387 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4388 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4389 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4391 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4392 /* i_block is stored in file system block size */
4393 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4394 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4395 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4401 * Post the struct inode info into an on-disk inode location in the
4402 * buffer-cache. This gobbles the caller's reference to the
4403 * buffer_head in the inode location struct.
4405 * The caller must have write access to iloc->bh.
4407 static int ext4_do_update_inode(handle_t
*handle
,
4408 struct inode
*inode
,
4409 struct ext4_iloc
*iloc
)
4411 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4412 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4413 struct buffer_head
*bh
= iloc
->bh
;
4414 int err
= 0, rc
, block
;
4415 int need_datasync
= 0;
4419 /* For fields not not tracking in the in-memory inode,
4420 * initialise them to zero for new inodes. */
4421 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4422 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4424 ext4_get_inode_flags(ei
);
4425 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4426 i_uid
= i_uid_read(inode
);
4427 i_gid
= i_gid_read(inode
);
4428 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4429 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4430 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4432 * Fix up interoperability with old kernels. Otherwise, old inodes get
4433 * re-used with the upper 16 bits of the uid/gid intact
4436 raw_inode
->i_uid_high
=
4437 cpu_to_le16(high_16_bits(i_uid
));
4438 raw_inode
->i_gid_high
=
4439 cpu_to_le16(high_16_bits(i_gid
));
4441 raw_inode
->i_uid_high
= 0;
4442 raw_inode
->i_gid_high
= 0;
4445 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4446 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4447 raw_inode
->i_uid_high
= 0;
4448 raw_inode
->i_gid_high
= 0;
4450 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4452 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4453 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4454 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4455 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4457 if (ext4_inode_blocks_set(handle
, raw_inode
, ei
))
4459 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4460 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4461 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
4462 cpu_to_le32(EXT4_OS_HURD
))
4463 raw_inode
->i_file_acl_high
=
4464 cpu_to_le16(ei
->i_file_acl
>> 32);
4465 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4466 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4467 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4470 if (ei
->i_disksize
> 0x7fffffffULL
) {
4471 struct super_block
*sb
= inode
->i_sb
;
4472 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4473 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4474 EXT4_SB(sb
)->s_es
->s_rev_level
==
4475 cpu_to_le32(EXT4_GOOD_OLD_REV
)) {
4476 /* If this is the first large file
4477 * created, add a flag to the superblock.
4479 err
= ext4_journal_get_write_access(handle
,
4480 EXT4_SB(sb
)->s_sbh
);
4483 ext4_update_dynamic_rev(sb
);
4484 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4485 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4486 ext4_handle_sync(handle
);
4487 err
= ext4_handle_dirty_super(handle
, sb
);
4490 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4491 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4492 if (old_valid_dev(inode
->i_rdev
)) {
4493 raw_inode
->i_block
[0] =
4494 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4495 raw_inode
->i_block
[1] = 0;
4497 raw_inode
->i_block
[0] = 0;
4498 raw_inode
->i_block
[1] =
4499 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4500 raw_inode
->i_block
[2] = 0;
4502 } else if (!ext4_has_inline_data(inode
)) {
4503 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4504 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4507 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4508 if (ei
->i_extra_isize
) {
4509 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4510 raw_inode
->i_version_hi
=
4511 cpu_to_le32(inode
->i_version
>> 32);
4512 raw_inode
->i_extra_isize
= cpu_to_le16(ei
->i_extra_isize
);
4515 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4517 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4518 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4521 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4523 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4526 ext4_std_error(inode
->i_sb
, err
);
4531 * ext4_write_inode()
4533 * We are called from a few places:
4535 * - Within generic_file_write() for O_SYNC files.
4536 * Here, there will be no transaction running. We wait for any running
4537 * transaction to commit.
4539 * - Within sys_sync(), kupdate and such.
4540 * We wait on commit, if tol to.
4542 * - Within prune_icache() (PF_MEMALLOC == true)
4543 * Here we simply return. We can't afford to block kswapd on the
4546 * In all cases it is actually safe for us to return without doing anything,
4547 * because the inode has been copied into a raw inode buffer in
4548 * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
4551 * Note that we are absolutely dependent upon all inode dirtiers doing the
4552 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4553 * which we are interested.
4555 * It would be a bug for them to not do this. The code:
4557 * mark_inode_dirty(inode)
4559 * inode->i_size = expr;
4561 * is in error because a kswapd-driven write_inode() could occur while
4562 * `stuff()' is running, and the new i_size will be lost. Plus the inode
4563 * will no longer be on the superblock's dirty inode list.
4565 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4569 if (current
->flags
& PF_MEMALLOC
)
4572 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4573 if (ext4_journal_current_handle()) {
4574 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4579 if (wbc
->sync_mode
!= WB_SYNC_ALL
)
4582 err
= ext4_force_commit(inode
->i_sb
);
4584 struct ext4_iloc iloc
;
4586 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4589 if (wbc
->sync_mode
== WB_SYNC_ALL
)
4590 sync_dirty_buffer(iloc
.bh
);
4591 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4592 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4593 "IO error syncing inode");
4602 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4603 * buffers that are attached to a page stradding i_size and are undergoing
4604 * commit. In that case we have to wait for commit to finish and try again.
4606 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4610 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4611 tid_t commit_tid
= 0;
4614 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4616 * All buffers in the last page remain valid? Then there's nothing to
4617 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4620 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4623 page
= find_lock_page(inode
->i_mapping
,
4624 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4627 ret
= __ext4_journalled_invalidatepage(page
, offset
);
4629 page_cache_release(page
);
4633 read_lock(&journal
->j_state_lock
);
4634 if (journal
->j_committing_transaction
)
4635 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4636 read_unlock(&journal
->j_state_lock
);
4638 jbd2_log_wait_commit(journal
, commit_tid
);
4645 * Called from notify_change.
4647 * We want to trap VFS attempts to truncate the file as soon as
4648 * possible. In particular, we want to make sure that when the VFS
4649 * shrinks i_size, we put the inode on the orphan list and modify
4650 * i_disksize immediately, so that during the subsequent flushing of
4651 * dirty pages and freeing of disk blocks, we can guarantee that any
4652 * commit will leave the blocks being flushed in an unused state on
4653 * disk. (On recovery, the inode will get truncated and the blocks will
4654 * be freed, so we have a strong guarantee that no future commit will
4655 * leave these blocks visible to the user.)
4657 * Another thing we have to assure is that if we are in ordered mode
4658 * and inode is still attached to the committing transaction, we must
4659 * we start writeout of all the dirty pages which are being truncated.
4660 * This way we are sure that all the data written in the previous
4661 * transaction are already on disk (truncate waits for pages under
4664 * Called with inode->i_mutex down.
4666 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4668 struct inode
*inode
= dentry
->d_inode
;
4671 const unsigned int ia_valid
= attr
->ia_valid
;
4673 error
= inode_change_ok(inode
, attr
);
4677 if (is_quota_modification(inode
, attr
))
4678 dquot_initialize(inode
);
4679 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4680 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4683 /* (user+group)*(old+new) structure, inode write (sb,
4684 * inode block, ? - but truncate inode update has it) */
4685 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4686 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4687 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4688 if (IS_ERR(handle
)) {
4689 error
= PTR_ERR(handle
);
4692 error
= dquot_transfer(inode
, attr
);
4694 ext4_journal_stop(handle
);
4697 /* Update corresponding info in inode so that everything is in
4698 * one transaction */
4699 if (attr
->ia_valid
& ATTR_UID
)
4700 inode
->i_uid
= attr
->ia_uid
;
4701 if (attr
->ia_valid
& ATTR_GID
)
4702 inode
->i_gid
= attr
->ia_gid
;
4703 error
= ext4_mark_inode_dirty(handle
, inode
);
4704 ext4_journal_stop(handle
);
4707 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4709 loff_t oldsize
= inode
->i_size
;
4711 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4712 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4714 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4718 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4719 inode_inc_iversion(inode
);
4721 if (S_ISREG(inode
->i_mode
) &&
4722 (attr
->ia_size
< inode
->i_size
)) {
4723 if (ext4_should_order_data(inode
)) {
4724 error
= ext4_begin_ordered_truncate(inode
,
4729 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4730 if (IS_ERR(handle
)) {
4731 error
= PTR_ERR(handle
);
4734 if (ext4_handle_valid(handle
)) {
4735 error
= ext4_orphan_add(handle
, inode
);
4738 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4739 rc
= ext4_mark_inode_dirty(handle
, inode
);
4742 ext4_journal_stop(handle
);
4744 ext4_orphan_del(NULL
, inode
);
4749 i_size_write(inode
, attr
->ia_size
);
4751 * Blocks are going to be removed from the inode. Wait
4752 * for dio in flight. Temporarily disable
4753 * dioread_nolock to prevent livelock.
4756 if (!ext4_should_journal_data(inode
)) {
4757 ext4_inode_block_unlocked_dio(inode
);
4758 inode_dio_wait(inode
);
4759 ext4_inode_resume_unlocked_dio(inode
);
4761 ext4_wait_for_tail_page_commit(inode
);
4764 * Truncate pagecache after we've waited for commit
4765 * in data=journal mode to make pages freeable.
4767 truncate_pagecache(inode
, oldsize
, inode
->i_size
);
4770 * We want to call ext4_truncate() even if attr->ia_size ==
4771 * inode->i_size for cases like truncation of fallocated space
4773 if (attr
->ia_valid
& ATTR_SIZE
)
4774 ext4_truncate(inode
);
4777 setattr_copy(inode
, attr
);
4778 mark_inode_dirty(inode
);
4782 * If the call to ext4_truncate failed to get a transaction handle at
4783 * all, we need to clean up the in-core orphan list manually.
4785 if (orphan
&& inode
->i_nlink
)
4786 ext4_orphan_del(NULL
, inode
);
4788 if (!rc
&& (ia_valid
& ATTR_MODE
))
4789 rc
= ext4_acl_chmod(inode
);
4792 ext4_std_error(inode
->i_sb
, error
);
4798 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4801 struct inode
*inode
;
4802 unsigned long long delalloc_blocks
;
4804 inode
= dentry
->d_inode
;
4805 generic_fillattr(inode
, stat
);
4808 * We can't update i_blocks if the block allocation is delayed
4809 * otherwise in the case of system crash before the real block
4810 * allocation is done, we will have i_blocks inconsistent with
4811 * on-disk file blocks.
4812 * We always keep i_blocks updated together with real
4813 * allocation. But to not confuse with user, stat
4814 * will return the blocks that include the delayed allocation
4815 * blocks for this file.
4817 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4818 EXT4_I(inode
)->i_reserved_data_blocks
);
4820 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
-9);
4824 static int ext4_index_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
4826 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4827 return ext4_ind_trans_blocks(inode
, nrblocks
, chunk
);
4828 return ext4_ext_index_trans_blocks(inode
, nrblocks
, chunk
);
4832 * Account for index blocks, block groups bitmaps and block group
4833 * descriptor blocks if modify datablocks and index blocks
4834 * worse case, the indexs blocks spread over different block groups
4836 * If datablocks are discontiguous, they are possible to spread over
4837 * different block groups too. If they are contiguous, with flexbg,
4838 * they could still across block group boundary.
4840 * Also account for superblock, inode, quota and xattr blocks
4842 static int ext4_meta_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
4844 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4850 * How many index blocks need to touch to modify nrblocks?
4851 * The "Chunk" flag indicating whether the nrblocks is
4852 * physically contiguous on disk
4854 * For Direct IO and fallocate, they calls get_block to allocate
4855 * one single extent at a time, so they could set the "Chunk" flag
4857 idxblocks
= ext4_index_trans_blocks(inode
, nrblocks
, chunk
);
4862 * Now let's see how many group bitmaps and group descriptors need
4872 if (groups
> ngroups
)
4874 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4875 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4877 /* bitmaps and block group descriptor blocks */
4878 ret
+= groups
+ gdpblocks
;
4880 /* Blocks for super block, inode, quota and xattr blocks */
4881 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4887 * Calculate the total number of credits to reserve to fit
4888 * the modification of a single pages into a single transaction,
4889 * which may include multiple chunks of block allocations.
4891 * This could be called via ext4_write_begin()
4893 * We need to consider the worse case, when
4894 * one new block per extent.
4896 int ext4_writepage_trans_blocks(struct inode
*inode
)
4898 int bpp
= ext4_journal_blocks_per_page(inode
);
4901 ret
= ext4_meta_trans_blocks(inode
, bpp
, 0);
4903 /* Account for data blocks for journalled mode */
4904 if (ext4_should_journal_data(inode
))
4910 * Calculate the journal credits for a chunk of data modification.
4912 * This is called from DIO, fallocate or whoever calling
4913 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4915 * journal buffers for data blocks are not included here, as DIO
4916 * and fallocate do no need to journal data buffers.
4918 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4920 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4924 * The caller must have previously called ext4_reserve_inode_write().
4925 * Give this, we know that the caller already has write access to iloc->bh.
4927 int ext4_mark_iloc_dirty(handle_t
*handle
,
4928 struct inode
*inode
, struct ext4_iloc
*iloc
)
4932 if (IS_I_VERSION(inode
))
4933 inode_inc_iversion(inode
);
4935 /* the do_update_inode consumes one bh->b_count */
4938 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4939 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4945 * On success, We end up with an outstanding reference count against
4946 * iloc->bh. This _must_ be cleaned up later.
4950 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4951 struct ext4_iloc
*iloc
)
4955 err
= ext4_get_inode_loc(inode
, iloc
);
4957 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4958 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4964 ext4_std_error(inode
->i_sb
, err
);
4969 * Expand an inode by new_extra_isize bytes.
4970 * Returns 0 on success or negative error number on failure.
4972 static int ext4_expand_extra_isize(struct inode
*inode
,
4973 unsigned int new_extra_isize
,
4974 struct ext4_iloc iloc
,
4977 struct ext4_inode
*raw_inode
;
4978 struct ext4_xattr_ibody_header
*header
;
4980 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
4983 raw_inode
= ext4_raw_inode(&iloc
);
4985 header
= IHDR(inode
, raw_inode
);
4987 /* No extended attributes present */
4988 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
4989 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4990 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
4992 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
4996 /* try to expand with EAs present */
4997 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
5002 * What we do here is to mark the in-core inode as clean with respect to inode
5003 * dirtiness (it may still be data-dirty).
5004 * This means that the in-core inode may be reaped by prune_icache
5005 * without having to perform any I/O. This is a very good thing,
5006 * because *any* task may call prune_icache - even ones which
5007 * have a transaction open against a different journal.
5009 * Is this cheating? Not really. Sure, we haven't written the
5010 * inode out, but prune_icache isn't a user-visible syncing function.
5011 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
5012 * we start and wait on commits.
5014 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
5016 struct ext4_iloc iloc
;
5017 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
5018 static unsigned int mnt_count
;
5022 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
5023 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
5024 if (ext4_handle_valid(handle
) &&
5025 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
5026 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
5028 * We need extra buffer credits since we may write into EA block
5029 * with this same handle. If journal_extend fails, then it will
5030 * only result in a minor loss of functionality for that inode.
5031 * If this is felt to be critical, then e2fsck should be run to
5032 * force a large enough s_min_extra_isize.
5034 if ((jbd2_journal_extend(handle
,
5035 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
5036 ret
= ext4_expand_extra_isize(inode
,
5037 sbi
->s_want_extra_isize
,
5040 ext4_set_inode_state(inode
,
5041 EXT4_STATE_NO_EXPAND
);
5043 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
5044 ext4_warning(inode
->i_sb
,
5045 "Unable to expand inode %lu. Delete"
5046 " some EAs or run e2fsck.",
5049 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
5055 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
5060 * ext4_dirty_inode() is called from __mark_inode_dirty()
5062 * We're really interested in the case where a file is being extended.
5063 * i_size has been changed by generic_commit_write() and we thus need
5064 * to include the updated inode in the current transaction.
5066 * Also, dquot_alloc_block() will always dirty the inode when blocks
5067 * are allocated to the file.
5069 * If the inode is marked synchronous, we don't honour that here - doing
5070 * so would cause a commit on atime updates, which we don't bother doing.
5071 * We handle synchronous inodes at the highest possible level.
5073 void ext4_dirty_inode(struct inode
*inode
, int flags
)
5077 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
5081 ext4_mark_inode_dirty(handle
, inode
);
5083 ext4_journal_stop(handle
);
5090 * Bind an inode's backing buffer_head into this transaction, to prevent
5091 * it from being flushed to disk early. Unlike
5092 * ext4_reserve_inode_write, this leaves behind no bh reference and
5093 * returns no iloc structure, so the caller needs to repeat the iloc
5094 * lookup to mark the inode dirty later.
5096 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
5098 struct ext4_iloc iloc
;
5102 err
= ext4_get_inode_loc(inode
, &iloc
);
5104 BUFFER_TRACE(iloc
.bh
, "get_write_access");
5105 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
5107 err
= ext4_handle_dirty_metadata(handle
,
5113 ext4_std_error(inode
->i_sb
, err
);
5118 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
5125 * We have to be very careful here: changing a data block's
5126 * journaling status dynamically is dangerous. If we write a
5127 * data block to the journal, change the status and then delete
5128 * that block, we risk forgetting to revoke the old log record
5129 * from the journal and so a subsequent replay can corrupt data.
5130 * So, first we make sure that the journal is empty and that
5131 * nobody is changing anything.
5134 journal
= EXT4_JOURNAL(inode
);
5137 if (is_journal_aborted(journal
))
5139 /* We have to allocate physical blocks for delalloc blocks
5140 * before flushing journal. otherwise delalloc blocks can not
5141 * be allocated any more. even more truncate on delalloc blocks
5142 * could trigger BUG by flushing delalloc blocks in journal.
5143 * There is no delalloc block in non-journal data mode.
5145 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5146 err
= ext4_alloc_da_blocks(inode
);
5151 /* Wait for all existing dio workers */
5152 ext4_inode_block_unlocked_dio(inode
);
5153 inode_dio_wait(inode
);
5155 jbd2_journal_lock_updates(journal
);
5158 * OK, there are no updates running now, and all cached data is
5159 * synced to disk. We are now in a completely consistent state
5160 * which doesn't have anything in the journal, and we know that
5161 * no filesystem updates are running, so it is safe to modify
5162 * the inode's in-core data-journaling state flag now.
5166 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5168 jbd2_journal_flush(journal
);
5169 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5171 ext4_set_aops(inode
);
5173 jbd2_journal_unlock_updates(journal
);
5174 ext4_inode_resume_unlocked_dio(inode
);
5176 /* Finally we can mark the inode as dirty. */
5178 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5180 return PTR_ERR(handle
);
5182 err
= ext4_mark_inode_dirty(handle
, inode
);
5183 ext4_handle_sync(handle
);
5184 ext4_journal_stop(handle
);
5185 ext4_std_error(inode
->i_sb
, err
);
5190 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5192 return !buffer_mapped(bh
);
5195 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5197 struct page
*page
= vmf
->page
;
5201 struct file
*file
= vma
->vm_file
;
5202 struct inode
*inode
= file_inode(file
);
5203 struct address_space
*mapping
= inode
->i_mapping
;
5205 get_block_t
*get_block
;
5208 sb_start_pagefault(inode
->i_sb
);
5209 file_update_time(vma
->vm_file
);
5210 /* Delalloc case is easy... */
5211 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5212 !ext4_should_journal_data(inode
) &&
5213 !ext4_nonda_switch(inode
->i_sb
)) {
5215 ret
= __block_page_mkwrite(vma
, vmf
,
5216 ext4_da_get_block_prep
);
5217 } while (ret
== -ENOSPC
&&
5218 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5223 size
= i_size_read(inode
);
5224 /* Page got truncated from under us? */
5225 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5227 ret
= VM_FAULT_NOPAGE
;
5231 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5232 len
= size
& ~PAGE_CACHE_MASK
;
5234 len
= PAGE_CACHE_SIZE
;
5236 * Return if we have all the buffers mapped. This avoids the need to do
5237 * journal_start/journal_stop which can block and take a long time
5239 if (page_has_buffers(page
)) {
5240 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5242 ext4_bh_unmapped
)) {
5243 /* Wait so that we don't change page under IO */
5244 wait_for_stable_page(page
);
5245 ret
= VM_FAULT_LOCKED
;
5250 /* OK, we need to fill the hole... */
5251 if (ext4_should_dioread_nolock(inode
))
5252 get_block
= ext4_get_block_write
;
5254 get_block
= ext4_get_block
;
5256 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5257 ext4_writepage_trans_blocks(inode
));
5258 if (IS_ERR(handle
)) {
5259 ret
= VM_FAULT_SIGBUS
;
5262 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5263 if (!ret
&& ext4_should_journal_data(inode
)) {
5264 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5265 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5267 ret
= VM_FAULT_SIGBUS
;
5268 ext4_journal_stop(handle
);
5271 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5273 ext4_journal_stop(handle
);
5274 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5277 ret
= block_page_mkwrite_return(ret
);
5279 sb_end_pagefault(inode
->i_sb
);