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>
49 #include <linux/blkdev.h>
51 #define MPAGE_DA_EXTENT_TAIL 0x01
53 static __u32
ext4_inode_csum(struct inode
*inode
, struct ext4_inode
*raw
,
54 struct ext4_inode_info
*ei
)
56 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
61 csum_lo
= le16_to_cpu(raw
->i_checksum_lo
);
62 raw
->i_checksum_lo
= 0;
63 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
64 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
)) {
65 csum_hi
= le16_to_cpu(raw
->i_checksum_hi
);
66 raw
->i_checksum_hi
= 0;
69 csum
= ext4_chksum(sbi
, ei
->i_csum_seed
, (__u8
*)raw
,
70 EXT4_INODE_SIZE(inode
->i_sb
));
72 raw
->i_checksum_lo
= cpu_to_le16(csum_lo
);
73 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
74 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
75 raw
->i_checksum_hi
= cpu_to_le16(csum_hi
);
80 static int ext4_inode_csum_verify(struct inode
*inode
, struct ext4_inode
*raw
,
81 struct ext4_inode_info
*ei
)
83 __u32 provided
, calculated
;
85 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
86 cpu_to_le32(EXT4_OS_LINUX
) ||
87 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
88 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
91 provided
= le16_to_cpu(raw
->i_checksum_lo
);
92 calculated
= ext4_inode_csum(inode
, raw
, ei
);
93 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
94 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
95 provided
|= ((__u32
)le16_to_cpu(raw
->i_checksum_hi
)) << 16;
99 return provided
== calculated
;
102 static void ext4_inode_csum_set(struct inode
*inode
, struct ext4_inode
*raw
,
103 struct ext4_inode_info
*ei
)
107 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
108 cpu_to_le32(EXT4_OS_LINUX
) ||
109 !EXT4_HAS_RO_COMPAT_FEATURE(inode
->i_sb
,
110 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
))
113 csum
= ext4_inode_csum(inode
, raw
, ei
);
114 raw
->i_checksum_lo
= cpu_to_le16(csum
& 0xFFFF);
115 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
&&
116 EXT4_FITS_IN_INODE(raw
, ei
, i_checksum_hi
))
117 raw
->i_checksum_hi
= cpu_to_le16(csum
>> 16);
120 static inline int ext4_begin_ordered_truncate(struct inode
*inode
,
123 trace_ext4_begin_ordered_truncate(inode
, new_size
);
125 * If jinode is zero, then we never opened the file for
126 * writing, so there's no need to call
127 * jbd2_journal_begin_ordered_truncate() since there's no
128 * outstanding writes we need to flush.
130 if (!EXT4_I(inode
)->jinode
)
132 return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode
),
133 EXT4_I(inode
)->jinode
,
137 static void ext4_invalidatepage(struct page
*page
, unsigned long offset
);
138 static int __ext4_journalled_writepage(struct page
*page
, unsigned int len
);
139 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
);
140 static int ext4_discard_partial_page_buffers_no_lock(handle_t
*handle
,
141 struct inode
*inode
, struct page
*page
, loff_t from
,
142 loff_t length
, int flags
);
145 * Test whether an inode is a fast symlink.
147 static int ext4_inode_is_fast_symlink(struct inode
*inode
)
149 int ea_blocks
= EXT4_I(inode
)->i_file_acl
?
150 (inode
->i_sb
->s_blocksize
>> 9) : 0;
152 return (S_ISLNK(inode
->i_mode
) && inode
->i_blocks
- ea_blocks
== 0);
156 * Restart the transaction associated with *handle. This does a commit,
157 * so before we call here everything must be consistently dirtied against
160 int ext4_truncate_restart_trans(handle_t
*handle
, struct inode
*inode
,
166 * Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
167 * moment, get_block can be called only for blocks inside i_size since
168 * page cache has been already dropped and writes are blocked by
169 * i_mutex. So we can safely drop the i_data_sem here.
171 BUG_ON(EXT4_JOURNAL(inode
) == NULL
);
172 jbd_debug(2, "restarting handle %p\n", handle
);
173 up_write(&EXT4_I(inode
)->i_data_sem
);
174 ret
= ext4_journal_restart(handle
, nblocks
);
175 down_write(&EXT4_I(inode
)->i_data_sem
);
176 ext4_discard_preallocations(inode
);
182 * Called at the last iput() if i_nlink is zero.
184 void ext4_evict_inode(struct inode
*inode
)
189 trace_ext4_evict_inode(inode
);
191 if (inode
->i_nlink
) {
193 * When journalling data dirty buffers are tracked only in the
194 * journal. So although mm thinks everything is clean and
195 * ready for reaping the inode might still have some pages to
196 * write in the running transaction or waiting to be
197 * checkpointed. Thus calling jbd2_journal_invalidatepage()
198 * (via truncate_inode_pages()) to discard these buffers can
199 * cause data loss. Also even if we did not discard these
200 * buffers, we would have no way to find them after the inode
201 * is reaped and thus user could see stale data if he tries to
202 * read them before the transaction is checkpointed. So be
203 * careful and force everything to disk here... We use
204 * ei->i_datasync_tid to store the newest transaction
205 * containing inode's data.
207 * Note that directories do not have this problem because they
208 * don't use page cache.
210 if (ext4_should_journal_data(inode
) &&
211 (S_ISLNK(inode
->i_mode
) || S_ISREG(inode
->i_mode
)) &&
212 inode
->i_ino
!= EXT4_JOURNAL_INO
) {
213 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
214 tid_t commit_tid
= EXT4_I(inode
)->i_datasync_tid
;
216 jbd2_complete_transaction(journal
, commit_tid
);
217 filemap_write_and_wait(&inode
->i_data
);
219 truncate_inode_pages(&inode
->i_data
, 0);
220 ext4_ioend_shutdown(inode
);
224 if (!is_bad_inode(inode
))
225 dquot_initialize(inode
);
227 if (ext4_should_order_data(inode
))
228 ext4_begin_ordered_truncate(inode
, 0);
229 truncate_inode_pages(&inode
->i_data
, 0);
230 ext4_ioend_shutdown(inode
);
232 if (is_bad_inode(inode
))
236 * Protect us against freezing - iput() caller didn't have to have any
237 * protection against it
239 sb_start_intwrite(inode
->i_sb
);
240 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
,
241 ext4_blocks_for_truncate(inode
)+3);
242 if (IS_ERR(handle
)) {
243 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
245 * If we're going to skip the normal cleanup, we still need to
246 * make sure that the in-core orphan linked list is properly
249 ext4_orphan_del(NULL
, inode
);
250 sb_end_intwrite(inode
->i_sb
);
255 ext4_handle_sync(handle
);
257 err
= ext4_mark_inode_dirty(handle
, inode
);
259 ext4_warning(inode
->i_sb
,
260 "couldn't mark inode dirty (err %d)", err
);
264 ext4_truncate(inode
);
267 * ext4_ext_truncate() doesn't reserve any slop when it
268 * restarts journal transactions; therefore there may not be
269 * enough credits left in the handle to remove the inode from
270 * the orphan list and set the dtime field.
272 if (!ext4_handle_has_enough_credits(handle
, 3)) {
273 err
= ext4_journal_extend(handle
, 3);
275 err
= ext4_journal_restart(handle
, 3);
277 ext4_warning(inode
->i_sb
,
278 "couldn't extend journal (err %d)", err
);
280 ext4_journal_stop(handle
);
281 ext4_orphan_del(NULL
, inode
);
282 sb_end_intwrite(inode
->i_sb
);
288 * Kill off the orphan record which ext4_truncate created.
289 * AKPM: I think this can be inside the above `if'.
290 * Note that ext4_orphan_del() has to be able to cope with the
291 * deletion of a non-existent orphan - this is because we don't
292 * know if ext4_truncate() actually created an orphan record.
293 * (Well, we could do this if we need to, but heck - it works)
295 ext4_orphan_del(handle
, inode
);
296 EXT4_I(inode
)->i_dtime
= get_seconds();
299 * One subtle ordering requirement: if anything has gone wrong
300 * (transaction abort, IO errors, whatever), then we can still
301 * do these next steps (the fs will already have been marked as
302 * having errors), but we can't free the inode if the mark_dirty
305 if (ext4_mark_inode_dirty(handle
, inode
))
306 /* If that failed, just do the required in-core inode clear. */
307 ext4_clear_inode(inode
);
309 ext4_free_inode(handle
, inode
);
310 ext4_journal_stop(handle
);
311 sb_end_intwrite(inode
->i_sb
);
314 ext4_clear_inode(inode
); /* We must guarantee clearing of inode... */
318 qsize_t
*ext4_get_reserved_space(struct inode
*inode
)
320 return &EXT4_I(inode
)->i_reserved_quota
;
325 * Calculate the number of metadata blocks need to reserve
326 * to allocate a block located at @lblock
328 static int ext4_calc_metadata_amount(struct inode
*inode
, ext4_lblk_t lblock
)
330 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
331 return ext4_ext_calc_metadata_amount(inode
, lblock
);
333 return ext4_ind_calc_metadata_amount(inode
, lblock
);
337 * Called with i_data_sem down, which is important since we can call
338 * ext4_discard_preallocations() from here.
340 void ext4_da_update_reserve_space(struct inode
*inode
,
341 int used
, int quota_claim
)
343 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
344 struct ext4_inode_info
*ei
= EXT4_I(inode
);
346 spin_lock(&ei
->i_block_reservation_lock
);
347 trace_ext4_da_update_reserve_space(inode
, used
, quota_claim
);
348 if (unlikely(used
> ei
->i_reserved_data_blocks
)) {
349 ext4_warning(inode
->i_sb
, "%s: ino %lu, used %d "
350 "with only %d reserved data blocks",
351 __func__
, inode
->i_ino
, used
,
352 ei
->i_reserved_data_blocks
);
354 used
= ei
->i_reserved_data_blocks
;
357 if (unlikely(ei
->i_allocated_meta_blocks
> ei
->i_reserved_meta_blocks
)) {
358 ext4_warning(inode
->i_sb
, "ino %lu, allocated %d "
359 "with only %d reserved metadata blocks "
360 "(releasing %d blocks with reserved %d data blocks)",
361 inode
->i_ino
, ei
->i_allocated_meta_blocks
,
362 ei
->i_reserved_meta_blocks
, used
,
363 ei
->i_reserved_data_blocks
);
365 ei
->i_allocated_meta_blocks
= ei
->i_reserved_meta_blocks
;
368 /* Update per-inode reservations */
369 ei
->i_reserved_data_blocks
-= used
;
370 ei
->i_reserved_meta_blocks
-= ei
->i_allocated_meta_blocks
;
371 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
372 used
+ ei
->i_allocated_meta_blocks
);
373 ei
->i_allocated_meta_blocks
= 0;
375 if (ei
->i_reserved_data_blocks
== 0) {
377 * We can release all of the reserved metadata blocks
378 * only when we have written all of the delayed
381 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
382 ei
->i_reserved_meta_blocks
);
383 ei
->i_reserved_meta_blocks
= 0;
384 ei
->i_da_metadata_calc_len
= 0;
386 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
388 /* Update quota subsystem for data blocks */
390 dquot_claim_block(inode
, EXT4_C2B(sbi
, used
));
393 * We did fallocate with an offset that is already delayed
394 * allocated. So on delayed allocated writeback we should
395 * not re-claim the quota for fallocated blocks.
397 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, used
));
401 * If we have done all the pending block allocations and if
402 * there aren't any writers on the inode, we can discard the
403 * inode's preallocations.
405 if ((ei
->i_reserved_data_blocks
== 0) &&
406 (atomic_read(&inode
->i_writecount
) == 0))
407 ext4_discard_preallocations(inode
);
410 static int __check_block_validity(struct inode
*inode
, const char *func
,
412 struct ext4_map_blocks
*map
)
414 if (!ext4_data_block_valid(EXT4_SB(inode
->i_sb
), map
->m_pblk
,
416 ext4_error_inode(inode
, func
, line
, map
->m_pblk
,
417 "lblock %lu mapped to illegal pblock "
418 "(length %d)", (unsigned long) map
->m_lblk
,
425 #define check_block_validity(inode, map) \
426 __check_block_validity((inode), __func__, __LINE__, (map))
429 * Return the number of contiguous dirty pages in a given inode
430 * starting at page frame idx.
432 static pgoff_t
ext4_num_dirty_pages(struct inode
*inode
, pgoff_t idx
,
433 unsigned int max_pages
)
435 struct address_space
*mapping
= inode
->i_mapping
;
439 int i
, nr_pages
, done
= 0;
443 pagevec_init(&pvec
, 0);
446 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
448 (pgoff_t
)PAGEVEC_SIZE
);
451 for (i
= 0; i
< nr_pages
; i
++) {
452 struct page
*page
= pvec
.pages
[i
];
453 struct buffer_head
*bh
, *head
;
456 if (unlikely(page
->mapping
!= mapping
) ||
458 PageWriteback(page
) ||
459 page
->index
!= idx
) {
464 if (page_has_buffers(page
)) {
465 bh
= head
= page_buffers(page
);
467 if (!buffer_delay(bh
) &&
468 !buffer_unwritten(bh
))
470 bh
= bh
->b_this_page
;
471 } while (!done
&& (bh
!= head
));
478 if (num
>= max_pages
) {
483 pagevec_release(&pvec
);
488 #ifdef ES_AGGRESSIVE_TEST
489 static void ext4_map_blocks_es_recheck(handle_t
*handle
,
491 struct ext4_map_blocks
*es_map
,
492 struct ext4_map_blocks
*map
,
499 * There is a race window that the result is not the same.
500 * e.g. xfstests #223 when dioread_nolock enables. The reason
501 * is that we lookup a block mapping in extent status tree with
502 * out taking i_data_sem. So at the time the unwritten extent
503 * could be converted.
505 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
506 down_read((&EXT4_I(inode
)->i_data_sem
));
507 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
508 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
509 EXT4_GET_BLOCKS_KEEP_SIZE
);
511 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
512 EXT4_GET_BLOCKS_KEEP_SIZE
);
514 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
515 up_read((&EXT4_I(inode
)->i_data_sem
));
517 * Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
518 * because it shouldn't be marked in es_map->m_flags.
520 map
->m_flags
&= ~(EXT4_MAP_FROM_CLUSTER
| EXT4_MAP_BOUNDARY
);
523 * We don't check m_len because extent will be collpased in status
524 * tree. So the m_len might not equal.
526 if (es_map
->m_lblk
!= map
->m_lblk
||
527 es_map
->m_flags
!= map
->m_flags
||
528 es_map
->m_pblk
!= map
->m_pblk
) {
529 printk("ES cache assertation failed for inode: %lu "
530 "es_cached ex [%d/%d/%llu/%x] != "
531 "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
532 inode
->i_ino
, es_map
->m_lblk
, es_map
->m_len
,
533 es_map
->m_pblk
, es_map
->m_flags
, map
->m_lblk
,
534 map
->m_len
, map
->m_pblk
, map
->m_flags
,
538 #endif /* ES_AGGRESSIVE_TEST */
541 * The ext4_map_blocks() function tries to look up the requested blocks,
542 * and returns if the blocks are already mapped.
544 * Otherwise it takes the write lock of the i_data_sem and allocate blocks
545 * and store the allocated blocks in the result buffer head and mark it
548 * If file type is extents based, it will call ext4_ext_map_blocks(),
549 * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
552 * On success, it returns the number of blocks being mapped or allocate.
553 * if create==0 and the blocks are pre-allocated and uninitialized block,
554 * the result buffer head is unmapped. If the create ==1, it will make sure
555 * the buffer head is mapped.
557 * It returns 0 if plain look up failed (blocks have not been allocated), in
558 * that case, buffer head is unmapped
560 * It returns the error in case of allocation failure.
562 int ext4_map_blocks(handle_t
*handle
, struct inode
*inode
,
563 struct ext4_map_blocks
*map
, int flags
)
565 struct extent_status es
;
567 #ifdef ES_AGGRESSIVE_TEST
568 struct ext4_map_blocks orig_map
;
570 memcpy(&orig_map
, map
, sizeof(*map
));
574 ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
575 "logical block %lu\n", inode
->i_ino
, flags
, map
->m_len
,
576 (unsigned long) map
->m_lblk
);
578 /* Lookup extent status tree firstly */
579 if (ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
580 if (ext4_es_is_written(&es
) || ext4_es_is_unwritten(&es
)) {
581 map
->m_pblk
= ext4_es_pblock(&es
) +
582 map
->m_lblk
- es
.es_lblk
;
583 map
->m_flags
|= ext4_es_is_written(&es
) ?
584 EXT4_MAP_MAPPED
: EXT4_MAP_UNWRITTEN
;
585 retval
= es
.es_len
- (map
->m_lblk
- es
.es_lblk
);
586 if (retval
> map
->m_len
)
589 } else if (ext4_es_is_delayed(&es
) || ext4_es_is_hole(&es
)) {
594 #ifdef ES_AGGRESSIVE_TEST
595 ext4_map_blocks_es_recheck(handle
, inode
, map
,
602 * Try to see if we can get the block without requesting a new
605 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
606 down_read((&EXT4_I(inode
)->i_data_sem
));
607 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
608 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
&
609 EXT4_GET_BLOCKS_KEEP_SIZE
);
611 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
&
612 EXT4_GET_BLOCKS_KEEP_SIZE
);
616 unsigned long long status
;
618 #ifdef ES_AGGRESSIVE_TEST
619 if (retval
!= map
->m_len
) {
620 printk("ES len assertation failed for inode: %lu "
621 "retval %d != map->m_len %d "
622 "in %s (lookup)\n", inode
->i_ino
, retval
,
623 map
->m_len
, __func__
);
627 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
628 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
629 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
630 ext4_find_delalloc_range(inode
, map
->m_lblk
,
631 map
->m_lblk
+ map
->m_len
- 1))
632 status
|= EXTENT_STATUS_DELAYED
;
633 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
,
634 map
->m_len
, map
->m_pblk
, status
);
638 if (!(flags
& EXT4_GET_BLOCKS_NO_LOCK
))
639 up_read((&EXT4_I(inode
)->i_data_sem
));
642 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
643 int ret
= check_block_validity(inode
, map
);
648 /* If it is only a block(s) look up */
649 if ((flags
& EXT4_GET_BLOCKS_CREATE
) == 0)
653 * Returns if the blocks have already allocated
655 * Note that if blocks have been preallocated
656 * ext4_ext_get_block() returns the create = 0
657 * with buffer head unmapped.
659 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
)
663 * Here we clear m_flags because after allocating an new extent,
664 * it will be set again.
666 map
->m_flags
&= ~EXT4_MAP_FLAGS
;
669 * New blocks allocate and/or writing to uninitialized extent
670 * will possibly result in updating i_data, so we take
671 * the write lock of i_data_sem, and call get_blocks()
672 * with create == 1 flag.
674 down_write((&EXT4_I(inode
)->i_data_sem
));
677 * if the caller is from delayed allocation writeout path
678 * we have already reserved fs blocks for allocation
679 * let the underlying get_block() function know to
680 * avoid double accounting
682 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
683 ext4_set_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
685 * We need to check for EXT4 here because migrate
686 * could have changed the inode type in between
688 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
689 retval
= ext4_ext_map_blocks(handle
, inode
, map
, flags
);
691 retval
= ext4_ind_map_blocks(handle
, inode
, map
, flags
);
693 if (retval
> 0 && map
->m_flags
& EXT4_MAP_NEW
) {
695 * We allocated new blocks which will result in
696 * i_data's format changing. Force the migrate
697 * to fail by clearing migrate flags
699 ext4_clear_inode_state(inode
, EXT4_STATE_EXT_MIGRATE
);
703 * Update reserved blocks/metadata blocks after successful
704 * block allocation which had been deferred till now. We don't
705 * support fallocate for non extent files. So we can update
706 * reserve space here.
709 (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
))
710 ext4_da_update_reserve_space(inode
, retval
, 1);
712 if (flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
)
713 ext4_clear_inode_state(inode
, EXT4_STATE_DELALLOC_RESERVED
);
717 unsigned long long status
;
719 #ifdef ES_AGGRESSIVE_TEST
720 if (retval
!= map
->m_len
) {
721 printk("ES len assertation failed for inode: %lu "
722 "retval %d != map->m_len %d "
723 "in %s (allocation)\n", inode
->i_ino
, retval
,
724 map
->m_len
, __func__
);
729 * If the extent has been zeroed out, we don't need to update
730 * extent status tree.
732 if ((flags
& EXT4_GET_BLOCKS_PRE_IO
) &&
733 ext4_es_lookup_extent(inode
, map
->m_lblk
, &es
)) {
734 if (ext4_es_is_written(&es
))
737 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
738 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
739 if (!(flags
& EXT4_GET_BLOCKS_DELALLOC_RESERVE
) &&
740 ext4_find_delalloc_range(inode
, map
->m_lblk
,
741 map
->m_lblk
+ map
->m_len
- 1))
742 status
|= EXTENT_STATUS_DELAYED
;
743 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
744 map
->m_pblk
, status
);
750 up_write((&EXT4_I(inode
)->i_data_sem
));
751 if (retval
> 0 && map
->m_flags
& EXT4_MAP_MAPPED
) {
752 int ret
= check_block_validity(inode
, map
);
759 /* Maximum number of blocks we map for direct IO at once. */
760 #define DIO_MAX_BLOCKS 4096
762 static int _ext4_get_block(struct inode
*inode
, sector_t iblock
,
763 struct buffer_head
*bh
, int flags
)
765 handle_t
*handle
= ext4_journal_current_handle();
766 struct ext4_map_blocks map
;
767 int ret
= 0, started
= 0;
770 if (ext4_has_inline_data(inode
))
774 map
.m_len
= bh
->b_size
>> inode
->i_blkbits
;
776 if (flags
&& !(flags
& EXT4_GET_BLOCKS_NO_LOCK
) && !handle
) {
777 /* Direct IO write... */
778 if (map
.m_len
> DIO_MAX_BLOCKS
)
779 map
.m_len
= DIO_MAX_BLOCKS
;
780 dio_credits
= ext4_chunk_trans_blocks(inode
, map
.m_len
);
781 handle
= ext4_journal_start(inode
, EXT4_HT_MAP_BLOCKS
,
783 if (IS_ERR(handle
)) {
784 ret
= PTR_ERR(handle
);
790 ret
= ext4_map_blocks(handle
, inode
, &map
, flags
);
792 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
793 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
794 bh
->b_size
= inode
->i_sb
->s_blocksize
* map
.m_len
;
798 ext4_journal_stop(handle
);
802 int ext4_get_block(struct inode
*inode
, sector_t iblock
,
803 struct buffer_head
*bh
, int create
)
805 return _ext4_get_block(inode
, iblock
, bh
,
806 create
? EXT4_GET_BLOCKS_CREATE
: 0);
810 * `handle' can be NULL if create is zero
812 struct buffer_head
*ext4_getblk(handle_t
*handle
, struct inode
*inode
,
813 ext4_lblk_t block
, int create
, int *errp
)
815 struct ext4_map_blocks map
;
816 struct buffer_head
*bh
;
819 J_ASSERT(handle
!= NULL
|| create
== 0);
823 err
= ext4_map_blocks(handle
, inode
, &map
,
824 create
? EXT4_GET_BLOCKS_CREATE
: 0);
826 /* ensure we send some value back into *errp */
829 if (create
&& err
== 0)
830 err
= -ENOSPC
; /* should never happen */
836 bh
= sb_getblk(inode
->i_sb
, map
.m_pblk
);
841 if (map
.m_flags
& EXT4_MAP_NEW
) {
842 J_ASSERT(create
!= 0);
843 J_ASSERT(handle
!= NULL
);
846 * Now that we do not always journal data, we should
847 * keep in mind whether this should always journal the
848 * new buffer as metadata. For now, regular file
849 * writes use ext4_get_block instead, so it's not a
853 BUFFER_TRACE(bh
, "call get_create_access");
854 fatal
= ext4_journal_get_create_access(handle
, bh
);
855 if (!fatal
&& !buffer_uptodate(bh
)) {
856 memset(bh
->b_data
, 0, inode
->i_sb
->s_blocksize
);
857 set_buffer_uptodate(bh
);
860 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
861 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
865 BUFFER_TRACE(bh
, "not a new buffer");
875 struct buffer_head
*ext4_bread(handle_t
*handle
, struct inode
*inode
,
876 ext4_lblk_t block
, int create
, int *err
)
878 struct buffer_head
*bh
;
880 bh
= ext4_getblk(handle
, inode
, block
, create
, err
);
883 if (buffer_uptodate(bh
))
885 ll_rw_block(READ
| REQ_META
| REQ_PRIO
, 1, &bh
);
887 if (buffer_uptodate(bh
))
894 int ext4_walk_page_buffers(handle_t
*handle
,
895 struct buffer_head
*head
,
899 int (*fn
)(handle_t
*handle
,
900 struct buffer_head
*bh
))
902 struct buffer_head
*bh
;
903 unsigned block_start
, block_end
;
904 unsigned blocksize
= head
->b_size
;
906 struct buffer_head
*next
;
908 for (bh
= head
, block_start
= 0;
909 ret
== 0 && (bh
!= head
|| !block_start
);
910 block_start
= block_end
, bh
= next
) {
911 next
= bh
->b_this_page
;
912 block_end
= block_start
+ blocksize
;
913 if (block_end
<= from
|| block_start
>= to
) {
914 if (partial
&& !buffer_uptodate(bh
))
918 err
= (*fn
)(handle
, bh
);
926 * To preserve ordering, it is essential that the hole instantiation and
927 * the data write be encapsulated in a single transaction. We cannot
928 * close off a transaction and start a new one between the ext4_get_block()
929 * and the commit_write(). So doing the jbd2_journal_start at the start of
930 * prepare_write() is the right place.
932 * Also, this function can nest inside ext4_writepage(). In that case, we
933 * *know* that ext4_writepage() has generated enough buffer credits to do the
934 * whole page. So we won't block on the journal in that case, which is good,
935 * because the caller may be PF_MEMALLOC.
937 * By accident, ext4 can be reentered when a transaction is open via
938 * quota file writes. If we were to commit the transaction while thus
939 * reentered, there can be a deadlock - we would be holding a quota
940 * lock, and the commit would never complete if another thread had a
941 * transaction open and was blocking on the quota lock - a ranking
944 * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
945 * will _not_ run commit under these circumstances because handle->h_ref
946 * is elevated. We'll still have enough credits for the tiny quotafile
949 int do_journal_get_write_access(handle_t
*handle
,
950 struct buffer_head
*bh
)
952 int dirty
= buffer_dirty(bh
);
955 if (!buffer_mapped(bh
) || buffer_freed(bh
))
958 * __block_write_begin() could have dirtied some buffers. Clean
959 * the dirty bit as jbd2_journal_get_write_access() could complain
960 * otherwise about fs integrity issues. Setting of the dirty bit
961 * by __block_write_begin() isn't a real problem here as we clear
962 * the bit before releasing a page lock and thus writeback cannot
963 * ever write the buffer.
966 clear_buffer_dirty(bh
);
967 ret
= ext4_journal_get_write_access(handle
, bh
);
969 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
973 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
974 struct buffer_head
*bh_result
, int create
);
975 static int ext4_write_begin(struct file
*file
, struct address_space
*mapping
,
976 loff_t pos
, unsigned len
, unsigned flags
,
977 struct page
**pagep
, void **fsdata
)
979 struct inode
*inode
= mapping
->host
;
980 int ret
, needed_blocks
;
986 #if defined(FEATURE_STORAGE_PID_LOGGER)
987 extern unsigned char *page_logger
;
988 struct page_pid_logger
*tmp_logger
;
989 unsigned long page_index
;
990 extern spinlock_t g_locker
;
991 unsigned long g_flags
;
994 trace_ext4_write_begin(inode
, pos
, len
, flags
);
996 * Reserve one block more for addition to orphan list in case
997 * we allocate blocks but write fails for some reason
999 needed_blocks
= ext4_writepage_trans_blocks(inode
) + 1;
1000 index
= pos
>> PAGE_CACHE_SHIFT
;
1001 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1004 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
1005 ret
= ext4_try_to_write_inline_data(mapping
, inode
, pos
, len
,
1014 * grab_cache_page_write_begin() can take a long time if the
1015 * system is thrashing due to memory pressure, or if the page
1016 * is being written back. So grab it first before we start
1017 * the transaction handle. This also allows us to allocate
1018 * the page (if needed) without using GFP_NOFS.
1021 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
1027 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, needed_blocks
);
1028 if (IS_ERR(handle
)) {
1029 page_cache_release(page
);
1030 return PTR_ERR(handle
);
1034 if (page
->mapping
!= mapping
) {
1035 /* The page got truncated from under us */
1037 page_cache_release(page
);
1038 ext4_journal_stop(handle
);
1041 wait_on_page_writeback(page
);
1043 if (ext4_should_dioread_nolock(inode
))
1044 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block_write
);
1046 ret
= __block_write_begin(page
, pos
, len
, ext4_get_block
);
1048 if (!ret
&& ext4_should_journal_data(inode
)) {
1049 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
),
1051 do_journal_get_write_access
);
1057 * __block_write_begin may have instantiated a few blocks
1058 * outside i_size. Trim these off again. Don't need
1059 * i_size_read because we hold i_mutex.
1061 * Add inode to orphan list in case we crash before
1064 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1065 ext4_orphan_add(handle
, inode
);
1067 ext4_journal_stop(handle
);
1068 if (pos
+ len
> inode
->i_size
) {
1069 ext4_truncate_failed_write(inode
);
1071 * If truncate failed early the inode might
1072 * still be on the orphan list; we need to
1073 * make sure the inode is removed from the
1074 * orphan list in that case.
1077 ext4_orphan_del(NULL
, inode
);
1080 if (ret
== -ENOSPC
&&
1081 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
1083 page_cache_release(page
);
1087 #if defined(FEATURE_STORAGE_PID_LOGGER)
1088 if( page_logger
&& (*pagep
)) {
1089 //#if defined(CONFIG_FLATMEM)
1090 //page_index = (unsigned long)((*pagep) - mem_map) ;
1092 page_index
= (unsigned long)(__page_to_pfn(*pagep
))- PHYS_PFN_OFFSET
;
1094 tmp_logger
=((struct page_pid_logger
*)page_logger
) + page_index
;
1095 spin_lock_irqsave(&g_locker
, g_flags
);
1096 if( page_index
< num_physpages
) {
1097 if( tmp_logger
->pid1
== 0XFFFF)
1098 tmp_logger
->pid1
= current
->pid
;
1099 else if( tmp_logger
->pid1
!= current
->pid
)
1100 tmp_logger
->pid2
= current
->pid
;
1102 spin_unlock_irqrestore(&g_locker
, g_flags
);
1108 /* For write_end() in data=journal mode */
1109 static int write_end_fn(handle_t
*handle
, struct buffer_head
*bh
)
1112 if (!buffer_mapped(bh
) || buffer_freed(bh
))
1114 set_buffer_uptodate(bh
);
1115 ret
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1116 clear_buffer_meta(bh
);
1117 clear_buffer_prio(bh
);
1122 * We need to pick up the new inode size which generic_commit_write gave us
1123 * `file' can be NULL - eg, when called from page_symlink().
1125 * ext4 never places buffers on inode->i_mapping->private_list. metadata
1126 * buffers are managed internally.
1128 static int ext4_write_end(struct file
*file
,
1129 struct address_space
*mapping
,
1130 loff_t pos
, unsigned len
, unsigned copied
,
1131 struct page
*page
, void *fsdata
)
1133 handle_t
*handle
= ext4_journal_current_handle();
1134 struct inode
*inode
= mapping
->host
;
1136 int i_size_changed
= 0;
1138 trace_ext4_write_end(inode
, pos
, len
, copied
);
1139 if (ext4_test_inode_state(inode
, EXT4_STATE_ORDERED_MODE
)) {
1140 ret
= ext4_jbd2_file_inode(handle
, inode
);
1143 page_cache_release(page
);
1148 if (ext4_has_inline_data(inode
)) {
1149 ret
= ext4_write_inline_data_end(inode
, pos
, len
,
1155 copied
= block_write_end(file
, mapping
, pos
,
1156 len
, copied
, page
, fsdata
);
1159 * No need to use i_size_read() here, the i_size
1160 * cannot change under us because we hole i_mutex.
1162 * But it's important to update i_size while still holding page lock:
1163 * page writeout could otherwise come in and zero beyond i_size.
1165 if (pos
+ copied
> inode
->i_size
) {
1166 i_size_write(inode
, pos
+ copied
);
1170 if (pos
+ copied
> EXT4_I(inode
)->i_disksize
) {
1171 /* We need to mark inode dirty even if
1172 * new_i_size is less that inode->i_size
1173 * but greater than i_disksize. (hint delalloc)
1175 ext4_update_i_disksize(inode
, (pos
+ copied
));
1179 page_cache_release(page
);
1182 * Don't mark the inode dirty under page lock. First, it unnecessarily
1183 * makes the holding time of page lock longer. Second, it forces lock
1184 * ordering of page lock and transaction start for journaling
1188 ext4_mark_inode_dirty(handle
, inode
);
1192 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1193 /* if we have allocated more blocks and copied
1194 * less. We will have blocks allocated outside
1195 * inode->i_size. So truncate them
1197 ext4_orphan_add(handle
, inode
);
1199 ret2
= ext4_journal_stop(handle
);
1203 if (pos
+ len
> inode
->i_size
) {
1204 ext4_truncate_failed_write(inode
);
1206 * If truncate failed early the inode might still be
1207 * on the orphan list; we need to make sure the inode
1208 * is removed from the orphan list in that case.
1211 ext4_orphan_del(NULL
, inode
);
1214 return ret
? ret
: copied
;
1217 static int ext4_journalled_write_end(struct file
*file
,
1218 struct address_space
*mapping
,
1219 loff_t pos
, unsigned len
, unsigned copied
,
1220 struct page
*page
, void *fsdata
)
1222 handle_t
*handle
= ext4_journal_current_handle();
1223 struct inode
*inode
= mapping
->host
;
1229 trace_ext4_journalled_write_end(inode
, pos
, len
, copied
);
1230 from
= pos
& (PAGE_CACHE_SIZE
- 1);
1233 BUG_ON(!ext4_handle_valid(handle
));
1235 if (ext4_has_inline_data(inode
))
1236 copied
= ext4_write_inline_data_end(inode
, pos
, len
,
1240 if (!PageUptodate(page
))
1242 page_zero_new_buffers(page
, from
+copied
, to
);
1245 ret
= ext4_walk_page_buffers(handle
, page_buffers(page
), from
,
1246 to
, &partial
, write_end_fn
);
1248 SetPageUptodate(page
);
1250 new_i_size
= pos
+ copied
;
1251 if (new_i_size
> inode
->i_size
)
1252 i_size_write(inode
, pos
+copied
);
1253 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
1254 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1255 if (new_i_size
> EXT4_I(inode
)->i_disksize
) {
1256 ext4_update_i_disksize(inode
, new_i_size
);
1257 ret2
= ext4_mark_inode_dirty(handle
, inode
);
1263 page_cache_release(page
);
1264 if (pos
+ len
> inode
->i_size
&& ext4_can_truncate(inode
))
1265 /* if we have allocated more blocks and copied
1266 * less. We will have blocks allocated outside
1267 * inode->i_size. So truncate them
1269 ext4_orphan_add(handle
, inode
);
1271 ret2
= ext4_journal_stop(handle
);
1274 if (pos
+ len
> inode
->i_size
) {
1275 ext4_truncate_failed_write(inode
);
1277 * If truncate failed early the inode might still be
1278 * on the orphan list; we need to make sure the inode
1279 * is removed from the orphan list in that case.
1282 ext4_orphan_del(NULL
, inode
);
1285 return ret
? ret
: copied
;
1289 * Reserve a metadata for a single block located at lblock
1291 static int ext4_da_reserve_metadata(struct inode
*inode
, ext4_lblk_t lblock
)
1293 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1294 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1295 unsigned int md_needed
;
1296 ext4_lblk_t save_last_lblock
;
1300 * recalculate the amount of metadata blocks to reserve
1301 * in order to allocate nrblocks
1302 * worse case is one extent per block
1304 spin_lock(&ei
->i_block_reservation_lock
);
1306 * ext4_calc_metadata_amount() has side effects, which we have
1307 * to be prepared undo if we fail to claim space.
1309 save_len
= ei
->i_da_metadata_calc_len
;
1310 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1311 md_needed
= EXT4_NUM_B2C(sbi
,
1312 ext4_calc_metadata_amount(inode
, lblock
));
1313 trace_ext4_da_reserve_space(inode
, md_needed
);
1316 * We do still charge estimated metadata to the sb though;
1317 * we cannot afford to run out of free blocks.
1319 if (ext4_claim_free_clusters(sbi
, md_needed
, 0)) {
1320 ei
->i_da_metadata_calc_len
= save_len
;
1321 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1322 spin_unlock(&ei
->i_block_reservation_lock
);
1325 ei
->i_reserved_meta_blocks
+= md_needed
;
1326 spin_unlock(&ei
->i_block_reservation_lock
);
1328 return 0; /* success */
1332 * Reserve a single cluster located at lblock
1334 static int ext4_da_reserve_space(struct inode
*inode
, ext4_lblk_t lblock
)
1336 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1337 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1338 unsigned int md_needed
;
1340 ext4_lblk_t save_last_lblock
;
1344 * We will charge metadata quota at writeout time; this saves
1345 * us from metadata over-estimation, though we may go over by
1346 * a small amount in the end. Here we just reserve for data.
1348 ret
= dquot_reserve_block(inode
, EXT4_C2B(sbi
, 1));
1353 * recalculate the amount of metadata blocks to reserve
1354 * in order to allocate nrblocks
1355 * worse case is one extent per block
1357 spin_lock(&ei
->i_block_reservation_lock
);
1359 * ext4_calc_metadata_amount() has side effects, which we have
1360 * to be prepared undo if we fail to claim space.
1362 save_len
= ei
->i_da_metadata_calc_len
;
1363 save_last_lblock
= ei
->i_da_metadata_calc_last_lblock
;
1364 md_needed
= EXT4_NUM_B2C(sbi
,
1365 ext4_calc_metadata_amount(inode
, lblock
));
1366 trace_ext4_da_reserve_space(inode
, md_needed
);
1369 * We do still charge estimated metadata to the sb though;
1370 * we cannot afford to run out of free blocks.
1372 if (ext4_claim_free_clusters(sbi
, md_needed
+ 1, 0)) {
1373 ei
->i_da_metadata_calc_len
= save_len
;
1374 ei
->i_da_metadata_calc_last_lblock
= save_last_lblock
;
1375 spin_unlock(&ei
->i_block_reservation_lock
);
1376 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, 1));
1379 ei
->i_reserved_data_blocks
++;
1380 ei
->i_reserved_meta_blocks
+= md_needed
;
1381 spin_unlock(&ei
->i_block_reservation_lock
);
1383 return 0; /* success */
1386 static void ext4_da_release_space(struct inode
*inode
, int to_free
)
1388 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1389 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1392 return; /* Nothing to release, exit */
1394 spin_lock(&EXT4_I(inode
)->i_block_reservation_lock
);
1396 trace_ext4_da_release_space(inode
, to_free
);
1397 if (unlikely(to_free
> ei
->i_reserved_data_blocks
)) {
1399 * if there aren't enough reserved blocks, then the
1400 * counter is messed up somewhere. Since this
1401 * function is called from invalidate page, it's
1402 * harmless to return without any action.
1404 ext4_warning(inode
->i_sb
, "ext4_da_release_space: "
1405 "ino %lu, to_free %d with only %d reserved "
1406 "data blocks", inode
->i_ino
, to_free
,
1407 ei
->i_reserved_data_blocks
);
1409 to_free
= ei
->i_reserved_data_blocks
;
1411 ei
->i_reserved_data_blocks
-= to_free
;
1413 if (ei
->i_reserved_data_blocks
== 0) {
1415 * We can release all of the reserved metadata blocks
1416 * only when we have written all of the delayed
1417 * allocation blocks.
1418 * Note that in case of bigalloc, i_reserved_meta_blocks,
1419 * i_reserved_data_blocks, etc. refer to number of clusters.
1421 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
,
1422 ei
->i_reserved_meta_blocks
);
1423 ei
->i_reserved_meta_blocks
= 0;
1424 ei
->i_da_metadata_calc_len
= 0;
1427 /* update fs dirty data blocks counter */
1428 percpu_counter_sub(&sbi
->s_dirtyclusters_counter
, to_free
);
1430 spin_unlock(&EXT4_I(inode
)->i_block_reservation_lock
);
1432 dquot_release_reservation_block(inode
, EXT4_C2B(sbi
, to_free
));
1435 static void ext4_da_page_release_reservation(struct page
*page
,
1436 unsigned long offset
)
1439 struct buffer_head
*head
, *bh
;
1440 unsigned int curr_off
= 0;
1441 struct inode
*inode
= page
->mapping
->host
;
1442 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1446 head
= page_buffers(page
);
1449 unsigned int next_off
= curr_off
+ bh
->b_size
;
1451 if ((offset
<= curr_off
) && (buffer_delay(bh
))) {
1453 clear_buffer_delay(bh
);
1455 curr_off
= next_off
;
1456 } while ((bh
= bh
->b_this_page
) != head
);
1459 lblk
= page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1460 ext4_es_remove_extent(inode
, lblk
, to_release
);
1463 /* If we have released all the blocks belonging to a cluster, then we
1464 * need to release the reserved space for that cluster. */
1465 num_clusters
= EXT4_NUM_B2C(sbi
, to_release
);
1466 while (num_clusters
> 0) {
1467 lblk
= (page
->index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
)) +
1468 ((num_clusters
- 1) << sbi
->s_cluster_bits
);
1469 if (sbi
->s_cluster_ratio
== 1 ||
1470 !ext4_find_delalloc_cluster(inode
, lblk
))
1471 ext4_da_release_space(inode
, 1);
1478 * Delayed allocation stuff
1482 * mpage_da_submit_io - walks through extent of pages and try to write
1483 * them with writepage() call back
1485 * @mpd->inode: inode
1486 * @mpd->first_page: first page of the extent
1487 * @mpd->next_page: page after the last page of the extent
1489 * By the time mpage_da_submit_io() is called we expect all blocks
1490 * to be allocated. this may be wrong if allocation failed.
1492 * As pages are already locked by write_cache_pages(), we can't use it
1494 static int mpage_da_submit_io(struct mpage_da_data
*mpd
,
1495 struct ext4_map_blocks
*map
)
1497 struct pagevec pvec
;
1498 unsigned long index
, end
;
1499 int ret
= 0, err
, nr_pages
, i
;
1500 struct inode
*inode
= mpd
->inode
;
1501 struct address_space
*mapping
= inode
->i_mapping
;
1502 loff_t size
= i_size_read(inode
);
1503 unsigned int len
, block_start
;
1504 struct buffer_head
*bh
, *page_bufs
= NULL
;
1505 sector_t pblock
= 0, cur_logical
= 0;
1506 struct ext4_io_submit io_submit
;
1508 BUG_ON(mpd
->next_page
<= mpd
->first_page
);
1509 memset(&io_submit
, 0, sizeof(io_submit
));
1511 * We need to start from the first_page to the next_page - 1
1512 * to make sure we also write the mapped dirty buffer_heads.
1513 * If we look at mpd->b_blocknr we would only be looking
1514 * at the currently mapped buffer_heads.
1516 index
= mpd
->first_page
;
1517 end
= mpd
->next_page
- 1;
1519 pagevec_init(&pvec
, 0);
1520 while (index
<= end
) {
1521 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1524 for (i
= 0; i
< nr_pages
; i
++) {
1526 struct page
*page
= pvec
.pages
[i
];
1528 index
= page
->index
;
1532 if (index
== size
>> PAGE_CACHE_SHIFT
)
1533 len
= size
& ~PAGE_CACHE_MASK
;
1535 len
= PAGE_CACHE_SIZE
;
1537 cur_logical
= index
<< (PAGE_CACHE_SHIFT
-
1539 pblock
= map
->m_pblk
+ (cur_logical
-
1544 BUG_ON(!PageLocked(page
));
1545 BUG_ON(PageWriteback(page
));
1547 bh
= page_bufs
= page_buffers(page
);
1550 if (map
&& (cur_logical
>= map
->m_lblk
) &&
1551 (cur_logical
<= (map
->m_lblk
+
1552 (map
->m_len
- 1)))) {
1553 if (buffer_delay(bh
)) {
1554 clear_buffer_delay(bh
);
1555 bh
->b_blocknr
= pblock
;
1557 if (buffer_unwritten(bh
) ||
1559 BUG_ON(bh
->b_blocknr
!= pblock
);
1560 if (map
->m_flags
& EXT4_MAP_UNINIT
)
1561 set_buffer_uninit(bh
);
1562 clear_buffer_unwritten(bh
);
1566 * skip page if block allocation undone and
1569 if (ext4_bh_delay_or_unwritten(NULL
, bh
))
1571 bh
= bh
->b_this_page
;
1572 block_start
+= bh
->b_size
;
1575 } while (bh
!= page_bufs
);
1582 clear_page_dirty_for_io(page
);
1583 err
= ext4_bio_write_page(&io_submit
, page
, len
,
1586 mpd
->pages_written
++;
1588 * In error case, we have to continue because
1589 * remaining pages are still locked
1594 pagevec_release(&pvec
);
1596 ext4_io_submit(&io_submit
);
1600 static void ext4_da_block_invalidatepages(struct mpage_da_data
*mpd
)
1604 struct pagevec pvec
;
1605 struct inode
*inode
= mpd
->inode
;
1606 struct address_space
*mapping
= inode
->i_mapping
;
1607 ext4_lblk_t start
, last
;
1609 index
= mpd
->first_page
;
1610 end
= mpd
->next_page
- 1;
1612 start
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1613 last
= end
<< (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
1614 ext4_es_remove_extent(inode
, start
, last
- start
+ 1);
1616 pagevec_init(&pvec
, 0);
1617 while (index
<= end
) {
1618 nr_pages
= pagevec_lookup(&pvec
, mapping
, index
, PAGEVEC_SIZE
);
1621 for (i
= 0; i
< nr_pages
; i
++) {
1622 struct page
*page
= pvec
.pages
[i
];
1623 if (page
->index
> end
)
1625 BUG_ON(!PageLocked(page
));
1626 BUG_ON(PageWriteback(page
));
1627 block_invalidatepage(page
, 0);
1628 ClearPageUptodate(page
);
1631 index
= pvec
.pages
[nr_pages
- 1]->index
+ 1;
1632 pagevec_release(&pvec
);
1637 static void ext4_print_free_blocks(struct inode
*inode
)
1639 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
1640 struct super_block
*sb
= inode
->i_sb
;
1641 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1643 ext4_msg(sb
, KERN_CRIT
, "Total free blocks count %lld",
1644 EXT4_C2B(EXT4_SB(inode
->i_sb
),
1645 ext4_count_free_clusters(sb
)));
1646 ext4_msg(sb
, KERN_CRIT
, "Free/Dirty block details");
1647 ext4_msg(sb
, KERN_CRIT
, "free_blocks=%lld",
1648 (long long) EXT4_C2B(EXT4_SB(sb
),
1649 percpu_counter_sum(&sbi
->s_freeclusters_counter
)));
1650 ext4_msg(sb
, KERN_CRIT
, "dirty_blocks=%lld",
1651 (long long) EXT4_C2B(EXT4_SB(sb
),
1652 percpu_counter_sum(&sbi
->s_dirtyclusters_counter
)));
1653 ext4_msg(sb
, KERN_CRIT
, "Block reservation details");
1654 ext4_msg(sb
, KERN_CRIT
, "i_reserved_data_blocks=%u",
1655 ei
->i_reserved_data_blocks
);
1656 ext4_msg(sb
, KERN_CRIT
, "i_reserved_meta_blocks=%u",
1657 ei
->i_reserved_meta_blocks
);
1658 ext4_msg(sb
, KERN_CRIT
, "i_allocated_meta_blocks=%u",
1659 ei
->i_allocated_meta_blocks
);
1664 * mpage_da_map_and_submit - go through given space, map them
1665 * if necessary, and then submit them for I/O
1667 * @mpd - bh describing space
1669 * The function skips space we know is already mapped to disk blocks.
1672 static void mpage_da_map_and_submit(struct mpage_da_data
*mpd
)
1674 int err
, blks
, get_blocks_flags
;
1675 struct ext4_map_blocks map
, *mapp
= NULL
;
1676 sector_t next
= mpd
->b_blocknr
;
1677 unsigned max_blocks
= mpd
->b_size
>> mpd
->inode
->i_blkbits
;
1678 loff_t disksize
= EXT4_I(mpd
->inode
)->i_disksize
;
1679 handle_t
*handle
= NULL
;
1682 * If the blocks are mapped already, or we couldn't accumulate
1683 * any blocks, then proceed immediately to the submission stage.
1685 if ((mpd
->b_size
== 0) ||
1686 ((mpd
->b_state
& (1 << BH_Mapped
)) &&
1687 !(mpd
->b_state
& (1 << BH_Delay
)) &&
1688 !(mpd
->b_state
& (1 << BH_Unwritten
))))
1691 handle
= ext4_journal_current_handle();
1695 * Call ext4_map_blocks() to allocate any delayed allocation
1696 * blocks, or to convert an uninitialized extent to be
1697 * initialized (in the case where we have written into
1698 * one or more preallocated blocks).
1700 * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to
1701 * indicate that we are on the delayed allocation path. This
1702 * affects functions in many different parts of the allocation
1703 * call path. This flag exists primarily because we don't
1704 * want to change *many* call functions, so ext4_map_blocks()
1705 * will set the EXT4_STATE_DELALLOC_RESERVED flag once the
1706 * inode's allocation semaphore is taken.
1708 * If the blocks in questions were delalloc blocks, set
1709 * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
1710 * variables are updated after the blocks have been allocated.
1713 map
.m_len
= max_blocks
;
1715 * We're in delalloc path and it is possible that we're going to
1716 * need more metadata blocks than previously reserved. However
1717 * we must not fail because we're in writeback and there is
1718 * nothing we can do about it so it might result in data loss.
1719 * So use reserved blocks to allocate metadata if possible.
1721 get_blocks_flags
= EXT4_GET_BLOCKS_CREATE
|
1722 EXT4_GET_BLOCKS_METADATA_NOFAIL
;
1723 if (ext4_should_dioread_nolock(mpd
->inode
))
1724 get_blocks_flags
|= EXT4_GET_BLOCKS_IO_CREATE_EXT
;
1725 if (mpd
->b_state
& (1 << BH_Delay
))
1726 get_blocks_flags
|= EXT4_GET_BLOCKS_DELALLOC_RESERVE
;
1729 blks
= ext4_map_blocks(handle
, mpd
->inode
, &map
, get_blocks_flags
);
1731 struct super_block
*sb
= mpd
->inode
->i_sb
;
1735 * If get block returns EAGAIN or ENOSPC and there
1736 * appears to be free blocks we will just let
1737 * mpage_da_submit_io() unlock all of the pages.
1742 if (err
== -ENOSPC
&& ext4_count_free_clusters(sb
)) {
1748 * get block failure will cause us to loop in
1749 * writepages, because a_ops->writepage won't be able
1750 * to make progress. The page will be redirtied by
1751 * writepage and writepages will again try to write
1754 if (!(EXT4_SB(sb
)->s_mount_flags
& EXT4_MF_FS_ABORTED
)) {
1755 ext4_msg(sb
, KERN_CRIT
,
1756 "delayed block allocation failed for inode %lu "
1757 "at logical offset %llu with max blocks %zd "
1758 "with error %d", mpd
->inode
->i_ino
,
1759 (unsigned long long) next
,
1760 mpd
->b_size
>> mpd
->inode
->i_blkbits
, err
);
1761 ext4_msg(sb
, KERN_CRIT
,
1762 "This should not happen!! Data will be lost");
1764 ext4_print_free_blocks(mpd
->inode
);
1766 /* invalidate all the pages */
1767 ext4_da_block_invalidatepages(mpd
);
1769 /* Mark this page range as having been completed */
1776 if (map
.m_flags
& EXT4_MAP_NEW
) {
1777 struct block_device
*bdev
= mpd
->inode
->i_sb
->s_bdev
;
1780 for (i
= 0; i
< map
.m_len
; i
++)
1781 unmap_underlying_metadata(bdev
, map
.m_pblk
+ i
);
1785 * Update on-disk size along with block allocation.
1787 disksize
= ((loff_t
) next
+ blks
) << mpd
->inode
->i_blkbits
;
1788 if (disksize
> i_size_read(mpd
->inode
))
1789 disksize
= i_size_read(mpd
->inode
);
1790 if (disksize
> EXT4_I(mpd
->inode
)->i_disksize
) {
1791 ext4_update_i_disksize(mpd
->inode
, disksize
);
1792 err
= ext4_mark_inode_dirty(handle
, mpd
->inode
);
1794 ext4_error(mpd
->inode
->i_sb
,
1795 "Failed to mark inode %lu dirty",
1800 mpage_da_submit_io(mpd
, mapp
);
1804 #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
1805 (1 << BH_Delay) | (1 << BH_Unwritten))
1808 * mpage_add_bh_to_extent - try to add one more block to extent of blocks
1810 * @mpd->lbh - extent of blocks
1811 * @logical - logical number of the block in the file
1812 * @b_state - b_state of the buffer head added
1814 * the function is used to collect contig. blocks in same state
1816 static void mpage_add_bh_to_extent(struct mpage_da_data
*mpd
, sector_t logical
,
1817 unsigned long b_state
)
1820 int blkbits
= mpd
->inode
->i_blkbits
;
1821 int nrblocks
= mpd
->b_size
>> blkbits
;
1824 * XXX Don't go larger than mballoc is willing to allocate
1825 * This is a stopgap solution. We eventually need to fold
1826 * mpage_da_submit_io() into this function and then call
1827 * ext4_map_blocks() multiple times in a loop
1829 if (nrblocks
>= (8*1024*1024 >> blkbits
))
1832 /* check if the reserved journal credits might overflow */
1833 if (!ext4_test_inode_flag(mpd
->inode
, EXT4_INODE_EXTENTS
)) {
1834 if (nrblocks
>= EXT4_MAX_TRANS_DATA
) {
1836 * With non-extent format we are limited by the journal
1837 * credit available. Total credit needed to insert
1838 * nrblocks contiguous blocks is dependent on the
1839 * nrblocks. So limit nrblocks.
1845 * First block in the extent
1847 if (mpd
->b_size
== 0) {
1848 mpd
->b_blocknr
= logical
;
1849 mpd
->b_size
= 1 << blkbits
;
1850 mpd
->b_state
= b_state
& BH_FLAGS
;
1854 next
= mpd
->b_blocknr
+ nrblocks
;
1856 * Can we merge the block to our big extent?
1858 if (logical
== next
&& (b_state
& BH_FLAGS
) == mpd
->b_state
) {
1859 mpd
->b_size
+= 1 << blkbits
;
1865 * We couldn't merge the block to our extent, so we
1866 * need to flush current extent and start new one
1868 mpage_da_map_and_submit(mpd
);
1872 static int ext4_bh_delay_or_unwritten(handle_t
*handle
, struct buffer_head
*bh
)
1874 return (buffer_delay(bh
) || buffer_unwritten(bh
)) && buffer_dirty(bh
);
1878 * This function is grabs code from the very beginning of
1879 * ext4_map_blocks, but assumes that the caller is from delayed write
1880 * time. This function looks up the requested blocks and sets the
1881 * buffer delay bit under the protection of i_data_sem.
1883 static int ext4_da_map_blocks(struct inode
*inode
, sector_t iblock
,
1884 struct ext4_map_blocks
*map
,
1885 struct buffer_head
*bh
)
1887 struct extent_status es
;
1889 sector_t invalid_block
= ~((sector_t
) 0xffff);
1890 #ifdef ES_AGGRESSIVE_TEST
1891 struct ext4_map_blocks orig_map
;
1893 memcpy(&orig_map
, map
, sizeof(*map
));
1896 if (invalid_block
< ext4_blocks_count(EXT4_SB(inode
->i_sb
)->s_es
))
1900 ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
1901 "logical block %lu\n", inode
->i_ino
, map
->m_len
,
1902 (unsigned long) map
->m_lblk
);
1904 /* Lookup extent status tree firstly */
1905 if (ext4_es_lookup_extent(inode
, iblock
, &es
)) {
1907 if (ext4_es_is_hole(&es
)) {
1909 down_read((&EXT4_I(inode
)->i_data_sem
));
1914 * Delayed extent could be allocated by fallocate.
1915 * So we need to check it.
1917 if (ext4_es_is_delayed(&es
) && !ext4_es_is_unwritten(&es
)) {
1918 map_bh(bh
, inode
->i_sb
, invalid_block
);
1920 set_buffer_delay(bh
);
1924 map
->m_pblk
= ext4_es_pblock(&es
) + iblock
- es
.es_lblk
;
1925 retval
= es
.es_len
- (iblock
- es
.es_lblk
);
1926 if (retval
> map
->m_len
)
1927 retval
= map
->m_len
;
1928 map
->m_len
= retval
;
1929 if (ext4_es_is_written(&es
))
1930 map
->m_flags
|= EXT4_MAP_MAPPED
;
1931 else if (ext4_es_is_unwritten(&es
))
1932 map
->m_flags
|= EXT4_MAP_UNWRITTEN
;
1936 #ifdef ES_AGGRESSIVE_TEST
1937 ext4_map_blocks_es_recheck(NULL
, inode
, map
, &orig_map
, 0);
1943 * Try to see if we can get the block without requesting a new
1944 * file system block.
1946 down_read((&EXT4_I(inode
)->i_data_sem
));
1947 if (ext4_has_inline_data(inode
)) {
1949 * We will soon create blocks for this page, and let
1950 * us pretend as if the blocks aren't allocated yet.
1951 * In case of clusters, we have to handle the work
1952 * of mapping from cluster so that the reserved space
1953 * is calculated properly.
1955 if ((EXT4_SB(inode
->i_sb
)->s_cluster_ratio
> 1) &&
1956 ext4_find_delalloc_cluster(inode
, map
->m_lblk
))
1957 map
->m_flags
|= EXT4_MAP_FROM_CLUSTER
;
1959 } else if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
1960 retval
= ext4_ext_map_blocks(NULL
, inode
, map
,
1961 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1963 retval
= ext4_ind_map_blocks(NULL
, inode
, map
,
1964 EXT4_GET_BLOCKS_NO_PUT_HOLE
);
1970 * XXX: __block_prepare_write() unmaps passed block,
1974 * If the block was allocated from previously allocated cluster,
1975 * then we don't need to reserve it again. However we still need
1976 * to reserve metadata for every block we're going to write.
1978 if (!(map
->m_flags
& EXT4_MAP_FROM_CLUSTER
)) {
1979 ret
= ext4_da_reserve_space(inode
, iblock
);
1981 /* not enough space to reserve */
1986 ret
= ext4_da_reserve_metadata(inode
, iblock
);
1988 /* not enough space to reserve */
1994 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
1995 ~0, EXTENT_STATUS_DELAYED
);
2001 /* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
2002 * and it should not appear on the bh->b_state.
2004 map
->m_flags
&= ~EXT4_MAP_FROM_CLUSTER
;
2006 map_bh(bh
, inode
->i_sb
, invalid_block
);
2008 set_buffer_delay(bh
);
2009 } else if (retval
> 0) {
2011 unsigned long long status
;
2013 #ifdef ES_AGGRESSIVE_TEST
2014 if (retval
!= map
->m_len
) {
2015 printk("ES len assertation failed for inode: %lu "
2016 "retval %d != map->m_len %d "
2017 "in %s (lookup)\n", inode
->i_ino
, retval
,
2018 map
->m_len
, __func__
);
2022 status
= map
->m_flags
& EXT4_MAP_UNWRITTEN
?
2023 EXTENT_STATUS_UNWRITTEN
: EXTENT_STATUS_WRITTEN
;
2024 ret
= ext4_es_insert_extent(inode
, map
->m_lblk
, map
->m_len
,
2025 map
->m_pblk
, status
);
2031 up_read((&EXT4_I(inode
)->i_data_sem
));
2037 * This is a special get_blocks_t callback which is used by
2038 * ext4_da_write_begin(). It will either return mapped block or
2039 * reserve space for a single block.
2041 * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
2042 * We also have b_blocknr = -1 and b_bdev initialized properly
2044 * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
2045 * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
2046 * initialized properly.
2048 int ext4_da_get_block_prep(struct inode
*inode
, sector_t iblock
,
2049 struct buffer_head
*bh
, int create
)
2051 struct ext4_map_blocks map
;
2054 BUG_ON(create
== 0);
2055 BUG_ON(bh
->b_size
!= inode
->i_sb
->s_blocksize
);
2057 map
.m_lblk
= iblock
;
2061 * first, we need to know whether the block is allocated already
2062 * preallocated blocks are unmapped but should treated
2063 * the same as allocated blocks.
2065 ret
= ext4_da_map_blocks(inode
, iblock
, &map
, bh
);
2069 map_bh(bh
, inode
->i_sb
, map
.m_pblk
);
2070 bh
->b_state
= (bh
->b_state
& ~EXT4_MAP_FLAGS
) | map
.m_flags
;
2072 if (buffer_unwritten(bh
)) {
2073 /* A delayed write to unwritten bh should be marked
2074 * new and mapped. Mapped ensures that we don't do
2075 * get_block multiple times when we write to the same
2076 * offset and new ensures that we do proper zero out
2077 * for partial write.
2080 set_buffer_mapped(bh
);
2085 static int bget_one(handle_t
*handle
, struct buffer_head
*bh
)
2091 static int bput_one(handle_t
*handle
, struct buffer_head
*bh
)
2097 static int __ext4_journalled_writepage(struct page
*page
,
2100 struct address_space
*mapping
= page
->mapping
;
2101 struct inode
*inode
= mapping
->host
;
2102 struct buffer_head
*page_bufs
= NULL
;
2103 handle_t
*handle
= NULL
;
2104 int ret
= 0, err
= 0;
2105 int inline_data
= ext4_has_inline_data(inode
);
2106 struct buffer_head
*inode_bh
= NULL
;
2108 ClearPageChecked(page
);
2111 BUG_ON(page
->index
!= 0);
2112 BUG_ON(len
> ext4_get_max_inline_size(inode
));
2113 inode_bh
= ext4_journalled_write_inline_data(inode
, len
, page
);
2114 if (inode_bh
== NULL
)
2117 page_bufs
= page_buffers(page
);
2122 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
2125 /* As soon as we unlock the page, it can go away, but we have
2126 * references to buffers so we are safe */
2129 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2130 ext4_writepage_trans_blocks(inode
));
2131 if (IS_ERR(handle
)) {
2132 ret
= PTR_ERR(handle
);
2136 BUG_ON(!ext4_handle_valid(handle
));
2139 ret
= ext4_journal_get_write_access(handle
, inode_bh
);
2141 err
= ext4_handle_dirty_metadata(handle
, inode
, inode_bh
);
2144 ret
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
2145 do_journal_get_write_access
);
2147 err
= ext4_walk_page_buffers(handle
, page_bufs
, 0, len
, NULL
,
2152 EXT4_I(inode
)->i_datasync_tid
= handle
->h_transaction
->t_tid
;
2153 err
= ext4_journal_stop(handle
);
2157 if (!ext4_has_inline_data(inode
))
2158 ext4_walk_page_buffers(handle
, page_bufs
, 0, len
,
2160 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
2167 * Note that we don't need to start a transaction unless we're journaling data
2168 * because we should have holes filled from ext4_page_mkwrite(). We even don't
2169 * need to file the inode to the transaction's list in ordered mode because if
2170 * we are writing back data added by write(), the inode is already there and if
2171 * we are writing back data modified via mmap(), no one guarantees in which
2172 * transaction the data will hit the disk. In case we are journaling data, we
2173 * cannot start transaction directly because transaction start ranks above page
2174 * lock so we have to do some magic.
2176 * This function can get called via...
2177 * - ext4_da_writepages after taking page lock (have journal handle)
2178 * - journal_submit_inode_data_buffers (no journal handle)
2179 * - shrink_page_list via the kswapd/direct reclaim (no journal handle)
2180 * - grab_page_cache when doing write_begin (have journal handle)
2182 * We don't do any block allocation in this function. If we have page with
2183 * multiple blocks we need to write those buffer_heads that are mapped. This
2184 * is important for mmaped based write. So if we do with blocksize 1K
2185 * truncate(f, 1024);
2186 * a = mmap(f, 0, 4096);
2188 * truncate(f, 4096);
2189 * we have in the page first buffer_head mapped via page_mkwrite call back
2190 * but other buffer_heads would be unmapped but dirty (dirty done via the
2191 * do_wp_page). So writepage should write the first block. If we modify
2192 * the mmap area beyond 1024 we will again get a page_fault and the
2193 * page_mkwrite callback will do the block allocation and mark the
2194 * buffer_heads mapped.
2196 * We redirty the page if we have any buffer_heads that is either delay or
2197 * unwritten in the page.
2199 * We can get recursively called as show below.
2201 * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
2204 * But since we don't do any block allocation we should not deadlock.
2205 * Page also have the dirty flag cleared so we don't get recurive page_lock.
2207 static int ext4_writepage(struct page
*page
,
2208 struct writeback_control
*wbc
)
2213 struct buffer_head
*page_bufs
= NULL
;
2214 struct inode
*inode
= page
->mapping
->host
;
2215 struct ext4_io_submit io_submit
;
2217 trace_ext4_writepage(page
);
2218 size
= i_size_read(inode
);
2219 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
2220 len
= size
& ~PAGE_CACHE_MASK
;
2222 len
= PAGE_CACHE_SIZE
;
2224 page_bufs
= page_buffers(page
);
2226 * We cannot do block allocation or other extent handling in this
2227 * function. If there are buffers needing that, we have to redirty
2228 * the page. But we may reach here when we do a journal commit via
2229 * journal_submit_inode_data_buffers() and in that case we must write
2230 * allocated buffers to achieve data=ordered mode guarantees.
2232 if (ext4_walk_page_buffers(NULL
, page_bufs
, 0, len
, NULL
,
2233 ext4_bh_delay_or_unwritten
)) {
2234 redirty_page_for_writepage(wbc
, page
);
2235 if (current
->flags
& PF_MEMALLOC
) {
2237 * For memory cleaning there's no point in writing only
2238 * some buffers. So just bail out. Warn if we came here
2239 * from direct reclaim.
2241 WARN_ON_ONCE((current
->flags
& (PF_MEMALLOC
|PF_KSWAPD
))
2248 if (PageChecked(page
) && ext4_should_journal_data(inode
))
2250 * It's mmapped pagecache. Add buffers and journal it. There
2251 * doesn't seem much point in redirtying the page here.
2253 return __ext4_journalled_writepage(page
, len
);
2255 memset(&io_submit
, 0, sizeof(io_submit
));
2256 ret
= ext4_bio_write_page(&io_submit
, page
, len
, wbc
);
2257 ext4_io_submit(&io_submit
);
2262 * This is called via ext4_da_writepages() to
2263 * calculate the total number of credits to reserve to fit
2264 * a single extent allocation into a single transaction,
2265 * ext4_da_writpeages() will loop calling this before
2266 * the block allocation.
2269 static int ext4_da_writepages_trans_blocks(struct inode
*inode
)
2271 int max_blocks
= EXT4_I(inode
)->i_reserved_data_blocks
;
2274 * With non-extent format the journal credit needed to
2275 * insert nrblocks contiguous block is dependent on
2276 * number of contiguous block. So we will limit
2277 * number of contiguous block to a sane value
2279 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) &&
2280 (max_blocks
> EXT4_MAX_TRANS_DATA
))
2281 max_blocks
= EXT4_MAX_TRANS_DATA
;
2283 return ext4_chunk_trans_blocks(inode
, max_blocks
);
2287 * write_cache_pages_da - walk the list of dirty pages of the given
2288 * address space and accumulate pages that need writing, and call
2289 * mpage_da_map_and_submit to map a single contiguous memory region
2290 * and then write them.
2292 static int write_cache_pages_da(handle_t
*handle
,
2293 struct address_space
*mapping
,
2294 struct writeback_control
*wbc
,
2295 struct mpage_da_data
*mpd
,
2296 pgoff_t
*done_index
)
2298 struct buffer_head
*bh
, *head
;
2299 struct inode
*inode
= mapping
->host
;
2300 struct pagevec pvec
;
2301 unsigned int nr_pages
;
2304 long nr_to_write
= wbc
->nr_to_write
;
2305 int i
, tag
, ret
= 0;
2307 memset(mpd
, 0, sizeof(struct mpage_da_data
));
2310 pagevec_init(&pvec
, 0);
2311 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2312 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2314 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2315 tag
= PAGECACHE_TAG_TOWRITE
;
2317 tag
= PAGECACHE_TAG_DIRTY
;
2319 *done_index
= index
;
2320 while (index
<= end
) {
2321 nr_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
, tag
,
2322 min(end
- index
, (pgoff_t
)PAGEVEC_SIZE
-1) + 1);
2326 for (i
= 0; i
< nr_pages
; i
++) {
2327 struct page
*page
= pvec
.pages
[i
];
2330 * At this point, the page may be truncated or
2331 * invalidated (changing page->mapping to NULL), or
2332 * even swizzled back from swapper_space to tmpfs file
2333 * mapping. However, page->index will not change
2334 * because we have a reference on the page.
2336 if (page
->index
> end
)
2339 *done_index
= page
->index
+ 1;
2342 * If we can't merge this page, and we have
2343 * accumulated an contiguous region, write it
2345 if ((mpd
->next_page
!= page
->index
) &&
2346 (mpd
->next_page
!= mpd
->first_page
)) {
2347 mpage_da_map_and_submit(mpd
);
2348 goto ret_extent_tail
;
2354 * If the page is no longer dirty, or its
2355 * mapping no longer corresponds to inode we
2356 * are writing (which means it has been
2357 * truncated or invalidated), or the page is
2358 * already under writeback and we are not
2359 * doing a data integrity writeback, skip the page
2361 if (!PageDirty(page
) ||
2362 (PageWriteback(page
) &&
2363 (wbc
->sync_mode
== WB_SYNC_NONE
)) ||
2364 unlikely(page
->mapping
!= mapping
)) {
2369 wait_on_page_writeback(page
);
2370 BUG_ON(PageWriteback(page
));
2373 * If we have inline data and arrive here, it means that
2374 * we will soon create the block for the 1st page, so
2375 * we'd better clear the inline data here.
2377 if (ext4_has_inline_data(inode
)) {
2378 BUG_ON(ext4_test_inode_state(inode
,
2379 EXT4_STATE_MAY_INLINE_DATA
));
2380 ext4_destroy_inline_data(handle
, inode
);
2383 if (mpd
->next_page
!= page
->index
)
2384 mpd
->first_page
= page
->index
;
2385 mpd
->next_page
= page
->index
+ 1;
2386 logical
= (sector_t
) page
->index
<<
2387 (PAGE_CACHE_SHIFT
- inode
->i_blkbits
);
2389 /* Add all dirty buffers to mpd */
2390 head
= page_buffers(page
);
2393 BUG_ON(buffer_locked(bh
));
2395 * We need to try to allocate unmapped blocks
2396 * in the same page. Otherwise we won't make
2397 * progress with the page in ext4_writepage
2399 if (ext4_bh_delay_or_unwritten(NULL
, bh
)) {
2400 mpage_add_bh_to_extent(mpd
, logical
,
2403 goto ret_extent_tail
;
2404 } else if (buffer_dirty(bh
) &&
2405 buffer_mapped(bh
)) {
2407 * mapped dirty buffer. We need to
2408 * update the b_state because we look
2409 * at b_state in mpage_da_map_blocks.
2410 * We don't update b_size because if we
2411 * find an unmapped buffer_head later
2412 * we need to use the b_state flag of
2415 if (mpd
->b_size
== 0)
2417 bh
->b_state
& BH_FLAGS
;
2420 } while ((bh
= bh
->b_this_page
) != head
);
2422 if (nr_to_write
> 0) {
2424 if (nr_to_write
== 0 &&
2425 wbc
->sync_mode
== WB_SYNC_NONE
)
2427 * We stop writing back only if we are
2428 * not doing integrity sync. In case of
2429 * integrity sync we have to keep going
2430 * because someone may be concurrently
2431 * dirtying pages, and we might have
2432 * synced a lot of newly appeared dirty
2433 * pages, but have not synced all of the
2439 pagevec_release(&pvec
);
2444 ret
= MPAGE_DA_EXTENT_TAIL
;
2446 pagevec_release(&pvec
);
2452 static int ext4_da_writepages(struct address_space
*mapping
,
2453 struct writeback_control
*wbc
)
2456 int range_whole
= 0;
2457 handle_t
*handle
= NULL
;
2458 struct mpage_da_data mpd
;
2459 struct inode
*inode
= mapping
->host
;
2460 int pages_written
= 0;
2461 unsigned int max_pages
;
2462 int range_cyclic
, cycled
= 1, io_done
= 0;
2463 int needed_blocks
, ret
= 0;
2464 long desired_nr_to_write
, nr_to_writebump
= 0;
2465 loff_t range_start
= wbc
->range_start
;
2466 struct ext4_sb_info
*sbi
= EXT4_SB(mapping
->host
->i_sb
);
2467 pgoff_t done_index
= 0;
2469 struct blk_plug plug
;
2471 trace_ext4_da_writepages(inode
, wbc
);
2474 * No pages to write? This is mainly a kludge to avoid starting
2475 * a transaction for special inodes like journal inode on last iput()
2476 * because that could violate lock ordering on umount
2478 if (!mapping
->nrpages
|| !mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
))
2482 * If the filesystem has aborted, it is read-only, so return
2483 * right away instead of dumping stack traces later on that
2484 * will obscure the real source of the problem. We test
2485 * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
2486 * the latter could be true if the filesystem is mounted
2487 * read-only, and in that case, ext4_da_writepages should
2488 * *never* be called, so if that ever happens, we would want
2491 if (unlikely(sbi
->s_mount_flags
& EXT4_MF_FS_ABORTED
))
2494 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
2497 range_cyclic
= wbc
->range_cyclic
;
2498 if (wbc
->range_cyclic
) {
2499 index
= mapping
->writeback_index
;
2502 wbc
->range_start
= index
<< PAGE_CACHE_SHIFT
;
2503 wbc
->range_end
= LLONG_MAX
;
2504 wbc
->range_cyclic
= 0;
2507 index
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
2508 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
2512 * This works around two forms of stupidity. The first is in
2513 * the writeback code, which caps the maximum number of pages
2514 * written to be 1024 pages. This is wrong on multiple
2515 * levels; different architectues have a different page size,
2516 * which changes the maximum amount of data which gets
2517 * written. Secondly, 4 megabytes is way too small. XFS
2518 * forces this value to be 16 megabytes by multiplying
2519 * nr_to_write parameter by four, and then relies on its
2520 * allocator to allocate larger extents to make them
2521 * contiguous. Unfortunately this brings us to the second
2522 * stupidity, which is that ext4's mballoc code only allocates
2523 * at most 2048 blocks. So we force contiguous writes up to
2524 * the number of dirty blocks in the inode, or
2525 * sbi->max_writeback_mb_bump whichever is smaller.
2527 max_pages
= sbi
->s_max_writeback_mb_bump
<< (20 - PAGE_CACHE_SHIFT
);
2528 if (!range_cyclic
&& range_whole
) {
2529 if (wbc
->nr_to_write
== LONG_MAX
)
2530 desired_nr_to_write
= wbc
->nr_to_write
;
2532 desired_nr_to_write
= wbc
->nr_to_write
* 8;
2534 desired_nr_to_write
= ext4_num_dirty_pages(inode
, index
,
2536 if (desired_nr_to_write
> max_pages
)
2537 desired_nr_to_write
= max_pages
;
2539 if (wbc
->nr_to_write
< desired_nr_to_write
) {
2540 nr_to_writebump
= desired_nr_to_write
- wbc
->nr_to_write
;
2541 wbc
->nr_to_write
= desired_nr_to_write
;
2545 if (wbc
->sync_mode
== WB_SYNC_ALL
|| wbc
->tagged_writepages
)
2546 tag_pages_for_writeback(mapping
, index
, end
);
2548 blk_start_plug(&plug
);
2549 while (!ret
&& wbc
->nr_to_write
> 0) {
2552 * we insert one extent at a time. So we need
2553 * credit needed for single extent allocation.
2554 * journalled mode is currently not supported
2557 BUG_ON(ext4_should_journal_data(inode
));
2558 needed_blocks
= ext4_da_writepages_trans_blocks(inode
);
2560 /* start a new transaction*/
2561 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
2563 if (IS_ERR(handle
)) {
2564 ret
= PTR_ERR(handle
);
2565 ext4_msg(inode
->i_sb
, KERN_CRIT
, "%s: jbd2_start: "
2566 "%ld pages, ino %lu; err %d", __func__
,
2567 wbc
->nr_to_write
, inode
->i_ino
, ret
);
2568 blk_finish_plug(&plug
);
2569 goto out_writepages
;
2573 * Now call write_cache_pages_da() to find the next
2574 * contiguous region of logical blocks that need
2575 * blocks to be allocated by ext4 and submit them.
2577 ret
= write_cache_pages_da(handle
, mapping
,
2578 wbc
, &mpd
, &done_index
);
2580 * If we have a contiguous extent of pages and we
2581 * haven't done the I/O yet, map the blocks and submit
2584 if (!mpd
.io_done
&& mpd
.next_page
!= mpd
.first_page
) {
2585 mpage_da_map_and_submit(&mpd
);
2586 ret
= MPAGE_DA_EXTENT_TAIL
;
2588 trace_ext4_da_write_pages(inode
, &mpd
);
2589 wbc
->nr_to_write
-= mpd
.pages_written
;
2591 ext4_journal_stop(handle
);
2593 if ((mpd
.retval
== -ENOSPC
) && sbi
->s_journal
) {
2594 /* commit the transaction which would
2595 * free blocks released in the transaction
2598 jbd2_journal_force_commit_nested(sbi
->s_journal
);
2600 } else if (ret
== MPAGE_DA_EXTENT_TAIL
) {
2602 * Got one extent now try with rest of the pages.
2603 * If mpd.retval is set -EIO, journal is aborted.
2604 * So we don't need to write any more.
2606 pages_written
+= mpd
.pages_written
;
2609 } else if (wbc
->nr_to_write
)
2611 * There is no more writeout needed
2612 * or we requested for a noblocking writeout
2613 * and we found the device congested
2617 blk_finish_plug(&plug
);
2618 if (!io_done
&& !cycled
) {
2621 wbc
->range_start
= index
<< PAGE_CACHE_SHIFT
;
2622 wbc
->range_end
= mapping
->writeback_index
- 1;
2627 wbc
->range_cyclic
= range_cyclic
;
2628 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
2630 * set the writeback_index so that range_cyclic
2631 * mode will write it back later
2633 mapping
->writeback_index
= done_index
;
2636 wbc
->nr_to_write
-= nr_to_writebump
;
2637 wbc
->range_start
= range_start
;
2638 trace_ext4_da_writepages_result(inode
, wbc
, ret
, pages_written
);
2642 static int ext4_nonda_switch(struct super_block
*sb
)
2644 s64 free_clusters
, dirty_clusters
;
2645 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
2648 * switch to non delalloc mode if we are running low
2649 * on free block. The free block accounting via percpu
2650 * counters can get slightly wrong with percpu_counter_batch getting
2651 * accumulated on each CPU without updating global counters
2652 * Delalloc need an accurate free block accounting. So switch
2653 * to non delalloc when we are near to error range.
2656 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
);
2658 percpu_counter_read_positive(&sbi
->s_dirtyclusters_counter
);
2660 * Start pushing delalloc when 1/2 of free blocks are dirty.
2662 if (dirty_clusters
&& (free_clusters
< 2 * dirty_clusters
))
2663 try_to_writeback_inodes_sb(sb
, WB_REASON_FS_FREE_SPACE
);
2665 if (2 * free_clusters
< 3 * dirty_clusters
||
2666 free_clusters
< (dirty_clusters
+ EXT4_FREECLUSTERS_WATERMARK
)) {
2668 * free block count is less than 150% of dirty blocks
2669 * or free blocks is less than watermark
2676 static int ext4_da_write_begin(struct file
*file
, struct address_space
*mapping
,
2677 loff_t pos
, unsigned len
, unsigned flags
,
2678 struct page
**pagep
, void **fsdata
)
2680 int ret
, retries
= 0;
2683 struct inode
*inode
= mapping
->host
;
2686 index
= pos
>> PAGE_CACHE_SHIFT
;
2688 if (ext4_nonda_switch(inode
->i_sb
)) {
2689 *fsdata
= (void *)FALL_BACK_TO_NONDELALLOC
;
2690 return ext4_write_begin(file
, mapping
, pos
,
2691 len
, flags
, pagep
, fsdata
);
2693 *fsdata
= (void *)0;
2694 trace_ext4_da_write_begin(inode
, pos
, len
, flags
);
2696 if (ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
)) {
2697 ret
= ext4_da_write_inline_data_begin(mapping
, inode
,
2707 * grab_cache_page_write_begin() can take a long time if the
2708 * system is thrashing due to memory pressure, or if the page
2709 * is being written back. So grab it first before we start
2710 * the transaction handle. This also allows us to allocate
2711 * the page (if needed) without using GFP_NOFS.
2714 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
2720 * With delayed allocation, we don't log the i_disksize update
2721 * if there is delayed block allocation. But we still need
2722 * to journalling the i_disksize update if writes to the end
2723 * of file which has an already mapped buffer.
2726 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
, 1);
2727 if (IS_ERR(handle
)) {
2728 page_cache_release(page
);
2729 return PTR_ERR(handle
);
2733 if (page
->mapping
!= mapping
) {
2734 /* The page got truncated from under us */
2736 page_cache_release(page
);
2737 ext4_journal_stop(handle
);
2740 /* In case writeback began while the page was unlocked */
2741 wait_on_page_writeback(page
);
2743 ret
= __block_write_begin(page
, pos
, len
, ext4_da_get_block_prep
);
2746 ext4_journal_stop(handle
);
2748 * block_write_begin may have instantiated a few blocks
2749 * outside i_size. Trim these off again. Don't need
2750 * i_size_read because we hold i_mutex.
2752 if (pos
+ len
> inode
->i_size
)
2753 ext4_truncate_failed_write(inode
);
2755 if (ret
== -ENOSPC
&&
2756 ext4_should_retry_alloc(inode
->i_sb
, &retries
))
2759 page_cache_release(page
);
2768 * Check if we should update i_disksize
2769 * when write to the end of file but not require block allocation
2771 static int ext4_da_should_update_i_disksize(struct page
*page
,
2772 unsigned long offset
)
2774 struct buffer_head
*bh
;
2775 struct inode
*inode
= page
->mapping
->host
;
2779 bh
= page_buffers(page
);
2780 idx
= offset
>> inode
->i_blkbits
;
2782 for (i
= 0; i
< idx
; i
++)
2783 bh
= bh
->b_this_page
;
2785 if (!buffer_mapped(bh
) || (buffer_delay(bh
)) || buffer_unwritten(bh
))
2790 static int ext4_da_write_end(struct file
*file
,
2791 struct address_space
*mapping
,
2792 loff_t pos
, unsigned len
, unsigned copied
,
2793 struct page
*page
, void *fsdata
)
2795 struct inode
*inode
= mapping
->host
;
2797 handle_t
*handle
= ext4_journal_current_handle();
2799 unsigned long start
, end
;
2800 int write_mode
= (int)(unsigned long)fsdata
;
2802 if (write_mode
== FALL_BACK_TO_NONDELALLOC
)
2803 return ext4_write_end(file
, mapping
, pos
,
2804 len
, copied
, page
, fsdata
);
2806 trace_ext4_da_write_end(inode
, pos
, len
, copied
);
2807 start
= pos
& (PAGE_CACHE_SIZE
- 1);
2808 end
= start
+ copied
- 1;
2811 * generic_write_end() will run mark_inode_dirty() if i_size
2812 * changes. So let's piggyback the i_disksize mark_inode_dirty
2815 new_i_size
= pos
+ copied
;
2816 if (copied
&& new_i_size
> EXT4_I(inode
)->i_disksize
) {
2817 if (ext4_has_inline_data(inode
) ||
2818 ext4_da_should_update_i_disksize(page
, end
)) {
2819 down_write(&EXT4_I(inode
)->i_data_sem
);
2820 if (new_i_size
> EXT4_I(inode
)->i_disksize
)
2821 EXT4_I(inode
)->i_disksize
= new_i_size
;
2822 up_write(&EXT4_I(inode
)->i_data_sem
);
2823 /* We need to mark inode dirty even if
2824 * new_i_size is less that inode->i_size
2825 * bu greater than i_disksize.(hint delalloc)
2827 ext4_mark_inode_dirty(handle
, inode
);
2831 if (write_mode
!= CONVERT_INLINE_DATA
&&
2832 ext4_test_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
) &&
2833 ext4_has_inline_data(inode
))
2834 ret2
= ext4_da_write_inline_data_end(inode
, pos
, len
, copied
,
2837 ret2
= generic_write_end(file
, mapping
, pos
, len
, copied
,
2843 ret2
= ext4_journal_stop(handle
);
2847 return ret
? ret
: copied
;
2850 static void ext4_da_invalidatepage(struct page
*page
, unsigned long offset
)
2853 * Drop reserved blocks
2855 BUG_ON(!PageLocked(page
));
2856 if (!page_has_buffers(page
))
2859 ext4_da_page_release_reservation(page
, offset
);
2862 ext4_invalidatepage(page
, offset
);
2868 * Force all delayed allocation blocks to be allocated for a given inode.
2870 int ext4_alloc_da_blocks(struct inode
*inode
)
2872 trace_ext4_alloc_da_blocks(inode
);
2874 if (!EXT4_I(inode
)->i_reserved_data_blocks
&&
2875 !EXT4_I(inode
)->i_reserved_meta_blocks
)
2879 * We do something simple for now. The filemap_flush() will
2880 * also start triggering a write of the data blocks, which is
2881 * not strictly speaking necessary (and for users of
2882 * laptop_mode, not even desirable). However, to do otherwise
2883 * would require replicating code paths in:
2885 * ext4_da_writepages() ->
2886 * write_cache_pages() ---> (via passed in callback function)
2887 * __mpage_da_writepage() -->
2888 * mpage_add_bh_to_extent()
2889 * mpage_da_map_blocks()
2891 * The problem is that write_cache_pages(), located in
2892 * mm/page-writeback.c, marks pages clean in preparation for
2893 * doing I/O, which is not desirable if we're not planning on
2896 * We could call write_cache_pages(), and then redirty all of
2897 * the pages by calling redirty_page_for_writepage() but that
2898 * would be ugly in the extreme. So instead we would need to
2899 * replicate parts of the code in the above functions,
2900 * simplifying them because we wouldn't actually intend to
2901 * write out the pages, but rather only collect contiguous
2902 * logical block extents, call the multi-block allocator, and
2903 * then update the buffer heads with the block allocations.
2905 * For now, though, we'll cheat by calling filemap_flush(),
2906 * which will map the blocks, and start the I/O, but not
2907 * actually wait for the I/O to complete.
2909 return filemap_flush(inode
->i_mapping
);
2913 * bmap() is special. It gets used by applications such as lilo and by
2914 * the swapper to find the on-disk block of a specific piece of data.
2916 * Naturally, this is dangerous if the block concerned is still in the
2917 * journal. If somebody makes a swapfile on an ext4 data-journaling
2918 * filesystem and enables swap, then they may get a nasty shock when the
2919 * data getting swapped to that swapfile suddenly gets overwritten by
2920 * the original zero's written out previously to the journal and
2921 * awaiting writeback in the kernel's buffer cache.
2923 * So, if we see any bmap calls here on a modified, data-journaled file,
2924 * take extra steps to flush any blocks which might be in the cache.
2926 static sector_t
ext4_bmap(struct address_space
*mapping
, sector_t block
)
2928 struct inode
*inode
= mapping
->host
;
2933 * We can get here for an inline file via the FIBMAP ioctl
2935 if (ext4_has_inline_data(inode
))
2938 if (mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
) &&
2939 test_opt(inode
->i_sb
, DELALLOC
)) {
2941 * With delalloc we want to sync the file
2942 * so that we can make sure we allocate
2945 filemap_write_and_wait(mapping
);
2948 if (EXT4_JOURNAL(inode
) &&
2949 ext4_test_inode_state(inode
, EXT4_STATE_JDATA
)) {
2951 * This is a REALLY heavyweight approach, but the use of
2952 * bmap on dirty files is expected to be extremely rare:
2953 * only if we run lilo or swapon on a freshly made file
2954 * do we expect this to happen.
2956 * (bmap requires CAP_SYS_RAWIO so this does not
2957 * represent an unprivileged user DOS attack --- we'd be
2958 * in trouble if mortal users could trigger this path at
2961 * NB. EXT4_STATE_JDATA is not set on files other than
2962 * regular files. If somebody wants to bmap a directory
2963 * or symlink and gets confused because the buffer
2964 * hasn't yet been flushed to disk, they deserve
2965 * everything they get.
2968 ext4_clear_inode_state(inode
, EXT4_STATE_JDATA
);
2969 journal
= EXT4_JOURNAL(inode
);
2970 jbd2_journal_lock_updates(journal
);
2971 err
= jbd2_journal_flush(journal
);
2972 jbd2_journal_unlock_updates(journal
);
2978 return generic_block_bmap(mapping
, block
, ext4_get_block
);
2981 static int ext4_readpage(struct file
*file
, struct page
*page
)
2984 struct inode
*inode
= page
->mapping
->host
;
2986 trace_ext4_readpage(page
);
2988 if (ext4_has_inline_data(inode
))
2989 ret
= ext4_readpage_inline(inode
, page
);
2992 return mpage_readpage(page
, ext4_get_block
);
2998 ext4_readpages(struct file
*file
, struct address_space
*mapping
,
2999 struct list_head
*pages
, unsigned nr_pages
)
3001 struct inode
*inode
= mapping
->host
;
3003 /* If the file has inline data, no need to do readpages. */
3004 if (ext4_has_inline_data(inode
))
3007 return mpage_readpages(mapping
, pages
, nr_pages
, ext4_get_block
);
3010 static void ext4_invalidatepage(struct page
*page
, unsigned long offset
)
3012 trace_ext4_invalidatepage(page
, offset
);
3014 /* No journalling happens on data buffers when this function is used */
3015 WARN_ON(page_has_buffers(page
) && buffer_jbd(page_buffers(page
)));
3017 block_invalidatepage(page
, offset
);
3020 static int __ext4_journalled_invalidatepage(struct page
*page
,
3021 unsigned long offset
)
3023 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
3025 trace_ext4_journalled_invalidatepage(page
, offset
);
3028 * If it's a full truncate we just forget about the pending dirtying
3031 ClearPageChecked(page
);
3033 return jbd2_journal_invalidatepage(journal
, page
, offset
);
3036 /* Wrapper for aops... */
3037 static void ext4_journalled_invalidatepage(struct page
*page
,
3038 unsigned long offset
)
3040 WARN_ON(__ext4_journalled_invalidatepage(page
, offset
) < 0);
3043 static int ext4_releasepage(struct page
*page
, gfp_t wait
)
3045 journal_t
*journal
= EXT4_JOURNAL(page
->mapping
->host
);
3047 trace_ext4_releasepage(page
);
3049 /* Page has dirty journalled data -> cannot release */
3050 if (PageChecked(page
))
3053 return jbd2_journal_try_to_free_buffers(journal
, page
, wait
);
3055 return try_to_free_buffers(page
);
3059 * ext4_get_block used when preparing for a DIO write or buffer write.
3060 * We allocate an uinitialized extent if blocks haven't been allocated.
3061 * The extent will be converted to initialized after the IO is complete.
3063 int ext4_get_block_write(struct inode
*inode
, sector_t iblock
,
3064 struct buffer_head
*bh_result
, int create
)
3066 ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
3067 inode
->i_ino
, create
);
3068 return _ext4_get_block(inode
, iblock
, bh_result
,
3069 EXT4_GET_BLOCKS_IO_CREATE_EXT
);
3072 static int ext4_get_block_write_nolock(struct inode
*inode
, sector_t iblock
,
3073 struct buffer_head
*bh_result
, int create
)
3075 ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
3076 inode
->i_ino
, create
);
3077 return _ext4_get_block(inode
, iblock
, bh_result
,
3078 EXT4_GET_BLOCKS_NO_LOCK
);
3081 static void ext4_end_io_dio(struct kiocb
*iocb
, loff_t offset
,
3082 ssize_t size
, void *private, int ret
,
3085 struct inode
*inode
= file_inode(iocb
->ki_filp
);
3086 ext4_io_end_t
*io_end
= iocb
->private;
3088 /* if not async direct IO or dio with 0 bytes write, just return */
3089 if (!io_end
|| !size
)
3092 ext_debug("ext4_end_io_dio(): io_end 0x%p "
3093 "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
3094 iocb
->private, io_end
->inode
->i_ino
, iocb
, offset
,
3097 iocb
->private = NULL
;
3099 /* if not aio dio with unwritten extents, just free io and return */
3100 if (!(io_end
->flag
& EXT4_IO_END_UNWRITTEN
)) {
3101 ext4_free_io_end(io_end
);
3103 inode_dio_done(inode
);
3105 aio_complete(iocb
, ret
, 0);
3109 io_end
->offset
= offset
;
3110 io_end
->size
= size
;
3112 io_end
->iocb
= iocb
;
3113 io_end
->result
= ret
;
3116 ext4_add_complete_io(io_end
);
3120 * For ext4 extent files, ext4 will do direct-io write to holes,
3121 * preallocated extents, and those write extend the file, no need to
3122 * fall back to buffered IO.
3124 * For holes, we fallocate those blocks, mark them as uninitialized
3125 * If those blocks were preallocated, we mark sure they are split, but
3126 * still keep the range to write as uninitialized.
3128 * The unwritten extents will be converted to written when DIO is completed.
3129 * For async direct IO, since the IO may still pending when return, we
3130 * set up an end_io call back function, which will do the conversion
3131 * when async direct IO completed.
3133 * If the O_DIRECT write will extend the file then add this inode to the
3134 * orphan list. So recovery will truncate it back to the original size
3135 * if the machine crashes during the write.
3138 static ssize_t
ext4_ext_direct_IO(int rw
, struct kiocb
*iocb
,
3139 const struct iovec
*iov
, loff_t offset
,
3140 unsigned long nr_segs
)
3142 struct file
*file
= iocb
->ki_filp
;
3143 struct inode
*inode
= file
->f_mapping
->host
;
3145 size_t count
= iov_length(iov
, nr_segs
);
3147 get_block_t
*get_block_func
= NULL
;
3149 loff_t final_size
= offset
+ count
;
3151 /* Use the old path for reads and writes beyond i_size. */
3152 if (rw
!= WRITE
|| final_size
> inode
->i_size
)
3153 return ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3155 BUG_ON(iocb
->private == NULL
);
3157 /* If we do a overwrite dio, i_mutex locking can be released */
3158 overwrite
= *((int *)iocb
->private);
3161 atomic_inc(&inode
->i_dio_count
);
3162 down_read(&EXT4_I(inode
)->i_data_sem
);
3163 mutex_unlock(&inode
->i_mutex
);
3167 * We could direct write to holes and fallocate.
3169 * Allocated blocks to fill the hole are marked as
3170 * uninitialized to prevent parallel buffered read to expose
3171 * the stale data before DIO complete the data IO.
3173 * As to previously fallocated extents, ext4 get_block will
3174 * just simply mark the buffer mapped but still keep the
3175 * extents uninitialized.
3177 * For non AIO case, we will convert those unwritten extents
3178 * to written after return back from blockdev_direct_IO.
3180 * For async DIO, the conversion needs to be deferred when the
3181 * IO is completed. The ext4 end_io callback function will be
3182 * called to take care of the conversion work. Here for async
3183 * case, we allocate an io_end structure to hook to the iocb.
3185 iocb
->private = NULL
;
3186 ext4_inode_aio_set(inode
, NULL
);
3187 if (!is_sync_kiocb(iocb
)) {
3188 ext4_io_end_t
*io_end
= ext4_init_io_end(inode
, GFP_NOFS
);
3193 io_end
->flag
|= EXT4_IO_END_DIRECT
;
3194 iocb
->private = io_end
;
3196 * we save the io structure for current async direct
3197 * IO, so that later ext4_map_blocks() could flag the
3198 * io structure whether there is a unwritten extents
3199 * needs to be converted when IO is completed.
3201 ext4_inode_aio_set(inode
, io_end
);
3205 get_block_func
= ext4_get_block_write_nolock
;
3207 get_block_func
= ext4_get_block_write
;
3208 dio_flags
= DIO_LOCKING
;
3210 ret
= __blockdev_direct_IO(rw
, iocb
, inode
,
3211 inode
->i_sb
->s_bdev
, iov
,
3219 ext4_inode_aio_set(inode
, NULL
);
3221 * The io_end structure takes a reference to the inode, that
3222 * structure needs to be destroyed and the reference to the
3223 * inode need to be dropped, when IO is complete, even with 0
3224 * byte write, or failed.
3226 * In the successful AIO DIO case, the io_end structure will
3227 * be destroyed and the reference to the inode will be dropped
3228 * after the end_io call back function is called.
3230 * In the case there is 0 byte write, or error case, since VFS
3231 * direct IO won't invoke the end_io call back function, we
3232 * need to free the end_io structure here.
3234 if (ret
!= -EIOCBQUEUED
&& ret
<= 0 && iocb
->private) {
3235 ext4_free_io_end(iocb
->private);
3236 iocb
->private = NULL
;
3237 } else if (ret
> 0 && !overwrite
&& ext4_test_inode_state(inode
,
3238 EXT4_STATE_DIO_UNWRITTEN
)) {
3241 * for non AIO case, since the IO is already
3242 * completed, we could do the conversion right here
3244 err
= ext4_convert_unwritten_extents(inode
,
3248 ext4_clear_inode_state(inode
, EXT4_STATE_DIO_UNWRITTEN
);
3252 /* take i_mutex locking again if we do a ovewrite dio */
3254 inode_dio_done(inode
);
3255 up_read(&EXT4_I(inode
)->i_data_sem
);
3256 mutex_lock(&inode
->i_mutex
);
3262 static ssize_t
ext4_direct_IO(int rw
, struct kiocb
*iocb
,
3263 const struct iovec
*iov
, loff_t offset
,
3264 unsigned long nr_segs
)
3266 struct file
*file
= iocb
->ki_filp
;
3267 struct inode
*inode
= file
->f_mapping
->host
;
3271 * If we are doing data journalling we don't support O_DIRECT
3273 if (ext4_should_journal_data(inode
))
3276 /* Let buffer I/O handle the inline data case. */
3277 if (ext4_has_inline_data(inode
))
3280 trace_ext4_direct_IO_enter(inode
, offset
, iov_length(iov
, nr_segs
), rw
);
3281 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3282 ret
= ext4_ext_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3284 ret
= ext4_ind_direct_IO(rw
, iocb
, iov
, offset
, nr_segs
);
3285 trace_ext4_direct_IO_exit(inode
, offset
,
3286 iov_length(iov
, nr_segs
), rw
, ret
);
3291 * Pages can be marked dirty completely asynchronously from ext4's journalling
3292 * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
3293 * much here because ->set_page_dirty is called under VFS locks. The page is
3294 * not necessarily locked.
3296 * We cannot just dirty the page and leave attached buffers clean, because the
3297 * buffers' dirty state is "definitive". We cannot just set the buffers dirty
3298 * or jbddirty because all the journalling code will explode.
3300 * So what we do is to mark the page "pending dirty" and next time writepage
3301 * is called, propagate that into the buffers appropriately.
3303 static int ext4_journalled_set_page_dirty(struct page
*page
)
3305 SetPageChecked(page
);
3306 return __set_page_dirty_nobuffers(page
);
3309 static const struct address_space_operations ext4_aops
= {
3310 .readpage
= ext4_readpage
,
3311 .readpages
= ext4_readpages
,
3312 .writepage
= ext4_writepage
,
3313 .write_begin
= ext4_write_begin
,
3314 .write_end
= ext4_write_end
,
3316 .invalidatepage
= ext4_invalidatepage
,
3317 .releasepage
= ext4_releasepage
,
3318 .direct_IO
= ext4_direct_IO
,
3319 .migratepage
= buffer_migrate_page
,
3320 .is_partially_uptodate
= block_is_partially_uptodate
,
3321 .error_remove_page
= generic_error_remove_page
,
3324 static const struct address_space_operations ext4_journalled_aops
= {
3325 .readpage
= ext4_readpage
,
3326 .readpages
= ext4_readpages
,
3327 .writepage
= ext4_writepage
,
3328 .write_begin
= ext4_write_begin
,
3329 .write_end
= ext4_journalled_write_end
,
3330 .set_page_dirty
= ext4_journalled_set_page_dirty
,
3332 .invalidatepage
= ext4_journalled_invalidatepage
,
3333 .releasepage
= ext4_releasepage
,
3334 .direct_IO
= ext4_direct_IO
,
3335 .is_partially_uptodate
= block_is_partially_uptodate
,
3336 .error_remove_page
= generic_error_remove_page
,
3339 static const struct address_space_operations ext4_da_aops
= {
3340 .readpage
= ext4_readpage
,
3341 .readpages
= ext4_readpages
,
3342 .writepage
= ext4_writepage
,
3343 .writepages
= ext4_da_writepages
,
3344 .write_begin
= ext4_da_write_begin
,
3345 .write_end
= ext4_da_write_end
,
3347 .invalidatepage
= ext4_da_invalidatepage
,
3348 .releasepage
= ext4_releasepage
,
3349 .direct_IO
= ext4_direct_IO
,
3350 .migratepage
= buffer_migrate_page
,
3351 .is_partially_uptodate
= block_is_partially_uptodate
,
3352 .error_remove_page
= generic_error_remove_page
,
3355 void ext4_set_aops(struct inode
*inode
)
3357 switch (ext4_inode_journal_mode(inode
)) {
3358 case EXT4_INODE_ORDERED_DATA_MODE
:
3359 ext4_set_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3361 case EXT4_INODE_WRITEBACK_DATA_MODE
:
3362 ext4_clear_inode_state(inode
, EXT4_STATE_ORDERED_MODE
);
3364 case EXT4_INODE_JOURNAL_DATA_MODE
:
3365 inode
->i_mapping
->a_ops
= &ext4_journalled_aops
;
3370 if (test_opt(inode
->i_sb
, DELALLOC
))
3371 inode
->i_mapping
->a_ops
= &ext4_da_aops
;
3373 inode
->i_mapping
->a_ops
= &ext4_aops
;
3378 * ext4_discard_partial_page_buffers()
3379 * Wrapper function for ext4_discard_partial_page_buffers_no_lock.
3380 * This function finds and locks the page containing the offset
3381 * "from" and passes it to ext4_discard_partial_page_buffers_no_lock.
3382 * Calling functions that already have the page locked should call
3383 * ext4_discard_partial_page_buffers_no_lock directly.
3385 int ext4_discard_partial_page_buffers(handle_t
*handle
,
3386 struct address_space
*mapping
, loff_t from
,
3387 loff_t length
, int flags
)
3389 struct inode
*inode
= mapping
->host
;
3393 page
= find_or_create_page(mapping
, from
>> PAGE_CACHE_SHIFT
,
3394 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
3398 err
= ext4_discard_partial_page_buffers_no_lock(handle
, inode
, page
,
3399 from
, length
, flags
);
3402 page_cache_release(page
);
3407 * ext4_discard_partial_page_buffers_no_lock()
3408 * Zeros a page range of length 'length' starting from offset 'from'.
3409 * Buffer heads that correspond to the block aligned regions of the
3410 * zeroed range will be unmapped. Unblock aligned regions
3411 * will have the corresponding buffer head mapped if needed so that
3412 * that region of the page can be updated with the partial zero out.
3414 * This function assumes that the page has already been locked. The
3415 * The range to be discarded must be contained with in the given page.
3416 * If the specified range exceeds the end of the page it will be shortened
3417 * to the end of the page that corresponds to 'from'. This function is
3418 * appropriate for updating a page and it buffer heads to be unmapped and
3419 * zeroed for blocks that have been either released, or are going to be
3422 * handle: The journal handle
3423 * inode: The files inode
3424 * page: A locked page that contains the offset "from"
3425 * from: The starting byte offset (from the beginning of the file)
3426 * to begin discarding
3427 * len: The length of bytes to discard
3428 * flags: Optional flags that may be used:
3430 * EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
3431 * Only zero the regions of the page whose buffer heads
3432 * have already been unmapped. This flag is appropriate
3433 * for updating the contents of a page whose blocks may
3434 * have already been released, and we only want to zero
3435 * out the regions that correspond to those released blocks.
3437 * Returns zero on success or negative on failure.
3439 static int ext4_discard_partial_page_buffers_no_lock(handle_t
*handle
,
3440 struct inode
*inode
, struct page
*page
, loff_t from
,
3441 loff_t length
, int flags
)
3443 ext4_fsblk_t index
= from
>> PAGE_CACHE_SHIFT
;
3444 unsigned int offset
= from
& (PAGE_CACHE_SIZE
-1);
3445 unsigned int blocksize
, max
, pos
;
3447 struct buffer_head
*bh
;
3450 blocksize
= inode
->i_sb
->s_blocksize
;
3451 max
= PAGE_CACHE_SIZE
- offset
;
3453 if (index
!= page
->index
)
3457 * correct length if it does not fall between
3458 * 'from' and the end of the page
3460 if (length
> max
|| length
< 0)
3463 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
3465 if (!page_has_buffers(page
))
3466 create_empty_buffers(page
, blocksize
, 0);
3468 /* Find the buffer that contains "offset" */
3469 bh
= page_buffers(page
);
3471 while (offset
>= pos
) {
3472 bh
= bh
->b_this_page
;
3478 while (pos
< offset
+ length
) {
3479 unsigned int end_of_block
, range_to_discard
;
3483 /* The length of space left to zero and unmap */
3484 range_to_discard
= offset
+ length
- pos
;
3486 /* The length of space until the end of the block */
3487 end_of_block
= blocksize
- (pos
& (blocksize
-1));
3490 * Do not unmap or zero past end of block
3491 * for this buffer head
3493 if (range_to_discard
> end_of_block
)
3494 range_to_discard
= end_of_block
;
3498 * Skip this buffer head if we are only zeroing unampped
3499 * regions of the page
3501 if (flags
& EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
&&
3505 /* If the range is block aligned, unmap */
3506 if (range_to_discard
== blocksize
) {
3507 clear_buffer_dirty(bh
);
3509 clear_buffer_mapped(bh
);
3510 clear_buffer_req(bh
);
3511 clear_buffer_new(bh
);
3512 clear_buffer_delay(bh
);
3513 clear_buffer_unwritten(bh
);
3514 clear_buffer_uptodate(bh
);
3515 zero_user(page
, pos
, range_to_discard
);
3516 BUFFER_TRACE(bh
, "Buffer discarded");
3521 * If this block is not completely contained in the range
3522 * to be discarded, then it is not going to be released. Because
3523 * we need to keep this block, we need to make sure this part
3524 * of the page is uptodate before we modify it by writeing
3525 * partial zeros on it.
3527 if (!buffer_mapped(bh
)) {
3529 * Buffer head must be mapped before we can read
3532 BUFFER_TRACE(bh
, "unmapped");
3533 ext4_get_block(inode
, iblock
, bh
, 0);
3534 /* unmapped? It's a hole - nothing to do */
3535 if (!buffer_mapped(bh
)) {
3536 BUFFER_TRACE(bh
, "still unmapped");
3541 /* Ok, it's mapped. Make sure it's up-to-date */
3542 if (PageUptodate(page
))
3543 set_buffer_uptodate(bh
);
3545 if (!buffer_uptodate(bh
)) {
3547 ll_rw_block(READ
, 1, &bh
);
3549 /* Uhhuh. Read error. Complain and punt.*/
3550 if (!buffer_uptodate(bh
))
3554 if (ext4_should_journal_data(inode
)) {
3555 BUFFER_TRACE(bh
, "get write access");
3556 err
= ext4_journal_get_write_access(handle
, bh
);
3561 zero_user(page
, pos
, range_to_discard
);
3564 if (ext4_should_journal_data(inode
)) {
3565 err
= ext4_handle_dirty_metadata(handle
, inode
, bh
);
3567 mark_buffer_dirty(bh
);
3569 BUFFER_TRACE(bh
, "Partial buffer zeroed");
3571 bh
= bh
->b_this_page
;
3573 pos
+= range_to_discard
;
3579 int ext4_can_truncate(struct inode
*inode
)
3581 if (S_ISREG(inode
->i_mode
))
3583 if (S_ISDIR(inode
->i_mode
))
3585 if (S_ISLNK(inode
->i_mode
))
3586 return !ext4_inode_is_fast_symlink(inode
);
3591 * ext4_punch_hole: punches a hole in a file by releaseing the blocks
3592 * associated with the given offset and length
3594 * @inode: File inode
3595 * @offset: The offset where the hole will begin
3596 * @len: The length of the hole
3598 * Returns: 0 on success or negative on failure
3601 int ext4_punch_hole(struct file
*file
, loff_t offset
, loff_t length
)
3604 struct inode
*inode
= file_inode(file
);
3605 struct super_block
*sb
= inode
->i_sb
;
3606 ext4_lblk_t first_block
, stop_block
;
3607 struct address_space
*mapping
= inode
->i_mapping
;
3608 loff_t first_page
, last_page
, page_len
;
3609 loff_t first_page_offset
, last_page_offset
;
3611 unsigned int credits
;
3614 if (!S_ISREG(inode
->i_mode
))
3617 if (EXT4_SB(sb
)->s_cluster_ratio
> 1) {
3618 /* TODO: Add support for bigalloc file systems */
3622 trace_ext4_punch_hole(inode
, offset
, length
);
3625 * Write out all dirty pages to avoid race conditions
3626 * Then release them.
3628 if (mapping
->nrpages
&& mapping_tagged(mapping
, PAGECACHE_TAG_DIRTY
)) {
3629 ret
= filemap_write_and_wait_range(mapping
, offset
,
3630 offset
+ length
- 1);
3635 mutex_lock(&inode
->i_mutex
);
3636 /* It's not possible punch hole on append only file */
3637 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
)) {
3641 if (IS_SWAPFILE(inode
)) {
3646 /* No need to punch hole beyond i_size */
3647 if (offset
>= inode
->i_size
)
3651 * If the hole extends beyond i_size, set the hole
3652 * to end after the page that contains i_size
3654 if (offset
+ length
> inode
->i_size
) {
3655 length
= inode
->i_size
+
3656 PAGE_CACHE_SIZE
- (inode
->i_size
& (PAGE_CACHE_SIZE
- 1)) -
3660 first_page
= (offset
+ PAGE_CACHE_SIZE
- 1) >> PAGE_CACHE_SHIFT
;
3661 last_page
= (offset
+ length
) >> PAGE_CACHE_SHIFT
;
3663 first_page_offset
= first_page
<< PAGE_CACHE_SHIFT
;
3664 last_page_offset
= last_page
<< PAGE_CACHE_SHIFT
;
3666 /* Now release the pages */
3667 if (last_page_offset
> first_page_offset
) {
3668 truncate_pagecache_range(inode
, first_page_offset
,
3669 last_page_offset
- 1);
3672 /* Wait all existing dio workers, newcomers will block on i_mutex */
3673 ext4_inode_block_unlocked_dio(inode
);
3674 ret
= ext4_flush_unwritten_io(inode
);
3677 inode_dio_wait(inode
);
3679 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3680 credits
= ext4_writepage_trans_blocks(inode
);
3682 credits
= ext4_blocks_for_truncate(inode
);
3683 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3684 if (IS_ERR(handle
)) {
3685 ret
= PTR_ERR(handle
);
3686 ext4_std_error(sb
, ret
);
3691 * Now we need to zero out the non-page-aligned data in the
3692 * pages at the start and tail of the hole, and unmap the
3693 * buffer heads for the block aligned regions of the page that
3694 * were completely zeroed.
3696 if (first_page
> last_page
) {
3698 * If the file space being truncated is contained
3699 * within a page just zero out and unmap the middle of
3702 ret
= ext4_discard_partial_page_buffers(handle
,
3703 mapping
, offset
, length
, 0);
3709 * zero out and unmap the partial page that contains
3710 * the start of the hole
3712 page_len
= first_page_offset
- offset
;
3714 ret
= ext4_discard_partial_page_buffers(handle
, mapping
,
3715 offset
, page_len
, 0);
3721 * zero out and unmap the partial page that contains
3722 * the end of the hole
3724 page_len
= offset
+ length
- last_page_offset
;
3726 ret
= ext4_discard_partial_page_buffers(handle
, mapping
,
3727 last_page_offset
, page_len
, 0);
3734 * If i_size is contained in the last page, we need to
3735 * unmap and zero the partial page after i_size
3737 if (inode
->i_size
>> PAGE_CACHE_SHIFT
== last_page
&&
3738 inode
->i_size
% PAGE_CACHE_SIZE
!= 0) {
3739 page_len
= PAGE_CACHE_SIZE
-
3740 (inode
->i_size
& (PAGE_CACHE_SIZE
- 1));
3743 ret
= ext4_discard_partial_page_buffers(handle
,
3744 mapping
, inode
->i_size
, page_len
, 0);
3751 first_block
= (offset
+ sb
->s_blocksize
- 1) >>
3752 EXT4_BLOCK_SIZE_BITS(sb
);
3753 stop_block
= (offset
+ length
) >> EXT4_BLOCK_SIZE_BITS(sb
);
3755 /* If there are no blocks to remove, return now */
3756 if (first_block
>= stop_block
)
3759 down_write(&EXT4_I(inode
)->i_data_sem
);
3760 ext4_discard_preallocations(inode
);
3762 ret
= ext4_es_remove_extent(inode
, first_block
,
3763 stop_block
- first_block
);
3765 up_write(&EXT4_I(inode
)->i_data_sem
);
3769 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3770 ret
= ext4_ext_remove_space(inode
, first_block
,
3773 ret
= ext4_free_hole_blocks(handle
, inode
, first_block
,
3776 ext4_discard_preallocations(inode
);
3777 up_write(&EXT4_I(inode
)->i_data_sem
);
3779 ext4_handle_sync(handle
);
3780 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3781 ext4_mark_inode_dirty(handle
, inode
);
3783 ext4_journal_stop(handle
);
3785 ext4_inode_resume_unlocked_dio(inode
);
3787 mutex_unlock(&inode
->i_mutex
);
3791 * Disabled as per b/28760453
3800 * We block out ext4_get_block() block instantiations across the entire
3801 * transaction, and VFS/VM ensures that ext4_truncate() cannot run
3802 * simultaneously on behalf of the same inode.
3804 * As we work through the truncate and commit bits of it to the journal there
3805 * is one core, guiding principle: the file's tree must always be consistent on
3806 * disk. We must be able to restart the truncate after a crash.
3808 * The file's tree may be transiently inconsistent in memory (although it
3809 * probably isn't), but whenever we close off and commit a journal transaction,
3810 * the contents of (the filesystem + the journal) must be consistent and
3811 * restartable. It's pretty simple, really: bottom up, right to left (although
3812 * left-to-right works OK too).
3814 * Note that at recovery time, journal replay occurs *before* the restart of
3815 * truncate against the orphan inode list.
3817 * The committed inode has the new, desired i_size (which is the same as
3818 * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
3819 * that this inode's truncate did not complete and it will again call
3820 * ext4_truncate() to have another go. So there will be instantiated blocks
3821 * to the right of the truncation point in a crashed ext4 filesystem. But
3822 * that's fine - as long as they are linked from the inode, the post-crash
3823 * ext4_truncate() run will find them and release them.
3825 void ext4_truncate(struct inode
*inode
)
3827 struct ext4_inode_info
*ei
= EXT4_I(inode
);
3828 unsigned int credits
;
3830 struct address_space
*mapping
= inode
->i_mapping
;
3834 * There is a possibility that we're either freeing the inode
3835 * or it completely new indode. In those cases we might not
3836 * have i_mutex locked because it's not necessary.
3838 if (!(inode
->i_state
& (I_NEW
|I_FREEING
)))
3839 WARN_ON(!mutex_is_locked(&inode
->i_mutex
));
3840 trace_ext4_truncate_enter(inode
);
3842 if (!ext4_can_truncate(inode
))
3845 ext4_clear_inode_flag(inode
, EXT4_INODE_EOFBLOCKS
);
3847 if (inode
->i_size
== 0 && !test_opt(inode
->i_sb
, NO_AUTO_DA_ALLOC
))
3848 ext4_set_inode_state(inode
, EXT4_STATE_DA_ALLOC_CLOSE
);
3850 if (ext4_has_inline_data(inode
)) {
3853 ext4_inline_data_truncate(inode
, &has_inline
);
3859 * finish any pending end_io work so we won't run the risk of
3860 * converting any truncated blocks to initialized later
3862 ext4_flush_unwritten_io(inode
);
3864 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3865 credits
= ext4_writepage_trans_blocks(inode
);
3867 credits
= ext4_blocks_for_truncate(inode
);
3869 handle
= ext4_journal_start(inode
, EXT4_HT_TRUNCATE
, credits
);
3870 if (IS_ERR(handle
)) {
3871 ext4_std_error(inode
->i_sb
, PTR_ERR(handle
));
3875 if (inode
->i_size
% PAGE_CACHE_SIZE
!= 0) {
3876 page_len
= PAGE_CACHE_SIZE
-
3877 (inode
->i_size
& (PAGE_CACHE_SIZE
- 1));
3879 if (ext4_discard_partial_page_buffers(handle
,
3880 mapping
, inode
->i_size
, page_len
, 0))
3885 * We add the inode to the orphan list, so that if this
3886 * truncate spans multiple transactions, and we crash, we will
3887 * resume the truncate when the filesystem recovers. It also
3888 * marks the inode dirty, to catch the new size.
3890 * Implication: the file must always be in a sane, consistent
3891 * truncatable state while each transaction commits.
3893 if (ext4_orphan_add(handle
, inode
))
3896 down_write(&EXT4_I(inode
)->i_data_sem
);
3898 ext4_discard_preallocations(inode
);
3900 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))
3901 ext4_ext_truncate(handle
, inode
);
3903 ext4_ind_truncate(handle
, inode
);
3905 up_write(&ei
->i_data_sem
);
3908 ext4_handle_sync(handle
);
3912 * If this was a simple ftruncate() and the file will remain alive,
3913 * then we need to clear up the orphan record which we created above.
3914 * However, if this was a real unlink then we were called by
3915 * ext4_delete_inode(), and we allow that function to clean up the
3916 * orphan info for us.
3919 ext4_orphan_del(handle
, inode
);
3921 inode
->i_mtime
= inode
->i_ctime
= ext4_current_time(inode
);
3922 ext4_mark_inode_dirty(handle
, inode
);
3923 ext4_journal_stop(handle
);
3925 trace_ext4_truncate_exit(inode
);
3929 * ext4_get_inode_loc returns with an extra refcount against the inode's
3930 * underlying buffer_head on success. If 'in_mem' is true, we have all
3931 * data in memory that is needed to recreate the on-disk version of this
3934 static int __ext4_get_inode_loc(struct inode
*inode
,
3935 struct ext4_iloc
*iloc
, int in_mem
)
3937 struct ext4_group_desc
*gdp
;
3938 struct buffer_head
*bh
;
3939 struct super_block
*sb
= inode
->i_sb
;
3941 int inodes_per_block
, inode_offset
;
3944 if (!ext4_valid_inum(sb
, inode
->i_ino
))
3947 iloc
->block_group
= (inode
->i_ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
3948 gdp
= ext4_get_group_desc(sb
, iloc
->block_group
, NULL
);
3953 * Figure out the offset within the block group inode table
3955 inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
3956 inode_offset
= ((inode
->i_ino
- 1) %
3957 EXT4_INODES_PER_GROUP(sb
));
3958 block
= ext4_inode_table(sb
, gdp
) + (inode_offset
/ inodes_per_block
);
3959 iloc
->offset
= (inode_offset
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
3961 bh
= sb_getblk(sb
, block
);
3964 if (!buffer_uptodate(bh
)) {
3968 * If the buffer has the write error flag, we have failed
3969 * to write out another inode in the same block. In this
3970 * case, we don't have to read the block because we may
3971 * read the old inode data successfully.
3973 if (buffer_write_io_error(bh
) && !buffer_uptodate(bh
))
3974 set_buffer_uptodate(bh
);
3976 if (buffer_uptodate(bh
)) {
3977 /* someone brought it uptodate while we waited */
3983 * If we have all information of the inode in memory and this
3984 * is the only valid inode in the block, we need not read the
3988 struct buffer_head
*bitmap_bh
;
3991 start
= inode_offset
& ~(inodes_per_block
- 1);
3993 /* Is the inode bitmap in cache? */
3994 bitmap_bh
= sb_getblk(sb
, ext4_inode_bitmap(sb
, gdp
));
3995 if (unlikely(!bitmap_bh
))
3999 * If the inode bitmap isn't in cache then the
4000 * optimisation may end up performing two reads instead
4001 * of one, so skip it.
4003 if (!buffer_uptodate(bitmap_bh
)) {
4007 for (i
= start
; i
< start
+ inodes_per_block
; i
++) {
4008 if (i
== inode_offset
)
4010 if (ext4_test_bit(i
, bitmap_bh
->b_data
))
4014 if (i
== start
+ inodes_per_block
) {
4015 /* all other inodes are free, so skip I/O */
4016 memset(bh
->b_data
, 0, bh
->b_size
);
4017 set_buffer_uptodate(bh
);
4025 * If we need to do any I/O, try to pre-readahead extra
4026 * blocks from the inode table.
4028 if (EXT4_SB(sb
)->s_inode_readahead_blks
) {
4029 ext4_fsblk_t b
, end
, table
;
4031 __u32 ra_blks
= EXT4_SB(sb
)->s_inode_readahead_blks
;
4033 table
= ext4_inode_table(sb
, gdp
);
4034 /* s_inode_readahead_blks is always a power of 2 */
4035 b
= block
& ~((ext4_fsblk_t
) ra_blks
- 1);
4039 num
= EXT4_INODES_PER_GROUP(sb
);
4040 if (ext4_has_group_desc_csum(sb
))
4041 num
-= ext4_itable_unused_count(sb
, gdp
);
4042 table
+= num
/ inodes_per_block
;
4046 sb_breadahead(sb
, b
++);
4050 * There are other valid inodes in the buffer, this inode
4051 * has in-inode xattrs, or we don't have this inode in memory.
4052 * Read the block from disk.
4054 trace_ext4_load_inode(inode
);
4056 bh
->b_end_io
= end_buffer_read_sync
;
4057 #ifdef FEATURE_STORAGE_META_LOG
4058 if( bh
&& bh
->b_bdev
&& bh
->b_bdev
->bd_disk
)
4059 set_metadata_rw_status(bh
->b_bdev
->bd_disk
->first_minor
, WAIT_READ_CNT
);
4061 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
4063 if (!buffer_uptodate(bh
)) {
4064 EXT4_ERROR_INODE_BLOCK(inode
, block
,
4065 "unable to read itable block");
4075 int ext4_get_inode_loc(struct inode
*inode
, struct ext4_iloc
*iloc
)
4077 /* We have all inode data except xattrs in memory here. */
4078 return __ext4_get_inode_loc(inode
, iloc
,
4079 !ext4_test_inode_state(inode
, EXT4_STATE_XATTR
));
4082 void ext4_set_inode_flags(struct inode
*inode
)
4084 unsigned int flags
= EXT4_I(inode
)->i_flags
;
4085 unsigned int new_fl
= 0;
4087 if (flags
& EXT4_SYNC_FL
)
4089 if (flags
& EXT4_APPEND_FL
)
4091 if (flags
& EXT4_IMMUTABLE_FL
)
4092 new_fl
|= S_IMMUTABLE
;
4093 if (flags
& EXT4_NOATIME_FL
)
4094 new_fl
|= S_NOATIME
;
4095 if (flags
& EXT4_DIRSYNC_FL
)
4096 new_fl
|= S_DIRSYNC
;
4097 set_mask_bits(&inode
->i_flags
,
4098 S_SYNC
|S_APPEND
|S_IMMUTABLE
|S_NOATIME
|S_DIRSYNC
, new_fl
);
4101 /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
4102 void ext4_get_inode_flags(struct ext4_inode_info
*ei
)
4104 unsigned int vfs_fl
;
4105 unsigned long old_fl
, new_fl
;
4108 vfs_fl
= ei
->vfs_inode
.i_flags
;
4109 old_fl
= ei
->i_flags
;
4110 new_fl
= old_fl
& ~(EXT4_SYNC_FL
|EXT4_APPEND_FL
|
4111 EXT4_IMMUTABLE_FL
|EXT4_NOATIME_FL
|
4113 if (vfs_fl
& S_SYNC
)
4114 new_fl
|= EXT4_SYNC_FL
;
4115 if (vfs_fl
& S_APPEND
)
4116 new_fl
|= EXT4_APPEND_FL
;
4117 if (vfs_fl
& S_IMMUTABLE
)
4118 new_fl
|= EXT4_IMMUTABLE_FL
;
4119 if (vfs_fl
& S_NOATIME
)
4120 new_fl
|= EXT4_NOATIME_FL
;
4121 if (vfs_fl
& S_DIRSYNC
)
4122 new_fl
|= EXT4_DIRSYNC_FL
;
4123 } while (cmpxchg(&ei
->i_flags
, old_fl
, new_fl
) != old_fl
);
4126 static blkcnt_t
ext4_inode_blocks(struct ext4_inode
*raw_inode
,
4127 struct ext4_inode_info
*ei
)
4130 struct inode
*inode
= &(ei
->vfs_inode
);
4131 struct super_block
*sb
= inode
->i_sb
;
4133 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4134 EXT4_FEATURE_RO_COMPAT_HUGE_FILE
)) {
4135 /* we are using combined 48 bit field */
4136 i_blocks
= ((u64
)le16_to_cpu(raw_inode
->i_blocks_high
)) << 32 |
4137 le32_to_cpu(raw_inode
->i_blocks_lo
);
4138 if (ext4_test_inode_flag(inode
, EXT4_INODE_HUGE_FILE
)) {
4139 /* i_blocks represent file system block size */
4140 return i_blocks
<< (inode
->i_blkbits
- 9);
4145 return le32_to_cpu(raw_inode
->i_blocks_lo
);
4149 static inline void ext4_iget_extra_inode(struct inode
*inode
,
4150 struct ext4_inode
*raw_inode
,
4151 struct ext4_inode_info
*ei
)
4153 __le32
*magic
= (void *)raw_inode
+
4154 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
;
4155 if (*magic
== cpu_to_le32(EXT4_XATTR_MAGIC
)) {
4156 ext4_set_inode_state(inode
, EXT4_STATE_XATTR
);
4157 ext4_find_inline_data_nolock(inode
);
4159 EXT4_I(inode
)->i_inline_off
= 0;
4162 struct inode
*ext4_iget(struct super_block
*sb
, unsigned long ino
)
4164 struct ext4_iloc iloc
;
4165 struct ext4_inode
*raw_inode
;
4166 struct ext4_inode_info
*ei
;
4167 struct inode
*inode
;
4168 journal_t
*journal
= EXT4_SB(sb
)->s_journal
;
4174 inode
= iget_locked(sb
, ino
);
4176 return ERR_PTR(-ENOMEM
);
4177 if (!(inode
->i_state
& I_NEW
))
4183 ret
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4186 raw_inode
= ext4_raw_inode(&iloc
);
4188 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4189 ei
->i_extra_isize
= le16_to_cpu(raw_inode
->i_extra_isize
);
4190 if (EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
>
4191 EXT4_INODE_SIZE(inode
->i_sb
)) {
4192 EXT4_ERROR_INODE(inode
, "bad extra_isize (%u != %u)",
4193 EXT4_GOOD_OLD_INODE_SIZE
+ ei
->i_extra_isize
,
4194 EXT4_INODE_SIZE(inode
->i_sb
));
4199 ei
->i_extra_isize
= 0;
4201 /* Precompute checksum seed for inode metadata */
4202 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4203 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
)) {
4204 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4206 __le32 inum
= cpu_to_le32(inode
->i_ino
);
4207 __le32 gen
= raw_inode
->i_generation
;
4208 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
4210 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
4214 if (!ext4_inode_csum_verify(inode
, raw_inode
, ei
)) {
4215 EXT4_ERROR_INODE(inode
, "checksum invalid");
4220 inode
->i_mode
= le16_to_cpu(raw_inode
->i_mode
);
4221 i_uid
= (uid_t
)le16_to_cpu(raw_inode
->i_uid_low
);
4222 i_gid
= (gid_t
)le16_to_cpu(raw_inode
->i_gid_low
);
4223 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4224 i_uid
|= le16_to_cpu(raw_inode
->i_uid_high
) << 16;
4225 i_gid
|= le16_to_cpu(raw_inode
->i_gid_high
) << 16;
4227 i_uid_write(inode
, i_uid
);
4228 i_gid_write(inode
, i_gid
);
4229 set_nlink(inode
, le16_to_cpu(raw_inode
->i_links_count
));
4231 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
4232 ei
->i_inline_off
= 0;
4233 ei
->i_dir_start_lookup
= 0;
4234 ei
->i_dtime
= le32_to_cpu(raw_inode
->i_dtime
);
4235 /* We now have enough fields to check if the inode was active or not.
4236 * This is needed because nfsd might try to access dead inodes
4237 * the test is that same one that e2fsck uses
4238 * NeilBrown 1999oct15
4240 if (inode
->i_nlink
== 0) {
4241 if ((inode
->i_mode
== 0 ||
4242 !(EXT4_SB(inode
->i_sb
)->s_mount_state
& EXT4_ORPHAN_FS
)) &&
4243 ino
!= EXT4_BOOT_LOADER_INO
) {
4244 /* this inode is deleted */
4248 /* The only unlinked inodes we let through here have
4249 * valid i_mode and are being read by the orphan
4250 * recovery code: that's fine, we're about to complete
4251 * the process of deleting those.
4252 * OR it is the EXT4_BOOT_LOADER_INO which is
4253 * not initialized on a new filesystem. */
4255 ei
->i_flags
= le32_to_cpu(raw_inode
->i_flags
);
4256 inode
->i_blocks
= ext4_inode_blocks(raw_inode
, ei
);
4257 ei
->i_file_acl
= le32_to_cpu(raw_inode
->i_file_acl_lo
);
4258 if (EXT4_HAS_INCOMPAT_FEATURE(sb
, EXT4_FEATURE_INCOMPAT_64BIT
))
4260 ((__u64
)le16_to_cpu(raw_inode
->i_file_acl_high
)) << 32;
4261 inode
->i_size
= ext4_isize(raw_inode
);
4262 ei
->i_disksize
= inode
->i_size
;
4264 ei
->i_reserved_quota
= 0;
4266 inode
->i_generation
= le32_to_cpu(raw_inode
->i_generation
);
4267 ei
->i_block_group
= iloc
.block_group
;
4268 ei
->i_last_alloc_group
= ~0;
4270 * NOTE! The in-memory inode i_data array is in little-endian order
4271 * even on big-endian machines: we do NOT byteswap the block numbers!
4273 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4274 ei
->i_data
[block
] = raw_inode
->i_block
[block
];
4275 INIT_LIST_HEAD(&ei
->i_orphan
);
4278 * Set transaction id's of transactions that have to be committed
4279 * to finish f[data]sync. We set them to currently running transaction
4280 * as we cannot be sure that the inode or some of its metadata isn't
4281 * part of the transaction - the inode could have been reclaimed and
4282 * now it is reread from disk.
4285 transaction_t
*transaction
;
4288 read_lock(&journal
->j_state_lock
);
4289 if (journal
->j_running_transaction
)
4290 transaction
= journal
->j_running_transaction
;
4292 transaction
= journal
->j_committing_transaction
;
4294 tid
= transaction
->t_tid
;
4296 tid
= journal
->j_commit_sequence
;
4297 read_unlock(&journal
->j_state_lock
);
4298 ei
->i_sync_tid
= tid
;
4299 ei
->i_datasync_tid
= tid
;
4302 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4303 if (ei
->i_extra_isize
== 0) {
4304 /* The extra space is currently unused. Use it. */
4305 ei
->i_extra_isize
= sizeof(struct ext4_inode
) -
4306 EXT4_GOOD_OLD_INODE_SIZE
;
4308 ext4_iget_extra_inode(inode
, raw_inode
, ei
);
4312 EXT4_INODE_GET_XTIME(i_ctime
, inode
, raw_inode
);
4313 EXT4_INODE_GET_XTIME(i_mtime
, inode
, raw_inode
);
4314 EXT4_INODE_GET_XTIME(i_atime
, inode
, raw_inode
);
4315 EXT4_EINODE_GET_XTIME(i_crtime
, ei
, raw_inode
);
4317 inode
->i_version
= le32_to_cpu(raw_inode
->i_disk_version
);
4318 if (EXT4_INODE_SIZE(inode
->i_sb
) > EXT4_GOOD_OLD_INODE_SIZE
) {
4319 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4321 (__u64
)(le32_to_cpu(raw_inode
->i_version_hi
)) << 32;
4325 if (ei
->i_file_acl
&&
4326 !ext4_data_block_valid(EXT4_SB(sb
), ei
->i_file_acl
, 1)) {
4327 EXT4_ERROR_INODE(inode
, "bad extended attribute block %llu",
4331 } else if (!ext4_has_inline_data(inode
)) {
4332 if (ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)) {
4333 if ((S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4334 (S_ISLNK(inode
->i_mode
) &&
4335 !ext4_inode_is_fast_symlink(inode
))))
4336 /* Validate extent which is part of inode */
4337 ret
= ext4_ext_check_inode(inode
);
4338 } else if (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) ||
4339 (S_ISLNK(inode
->i_mode
) &&
4340 !ext4_inode_is_fast_symlink(inode
))) {
4341 /* Validate block references which are part of inode */
4342 ret
= ext4_ind_check_inode(inode
);
4348 if (S_ISREG(inode
->i_mode
)) {
4349 inode
->i_op
= &ext4_file_inode_operations
;
4350 inode
->i_fop
= &ext4_file_operations
;
4351 ext4_set_aops(inode
);
4352 } else if (S_ISDIR(inode
->i_mode
)) {
4353 inode
->i_op
= &ext4_dir_inode_operations
;
4354 inode
->i_fop
= &ext4_dir_operations
;
4355 } else if (S_ISLNK(inode
->i_mode
)) {
4356 if (ext4_inode_is_fast_symlink(inode
)) {
4357 inode
->i_op
= &ext4_fast_symlink_inode_operations
;
4358 nd_terminate_link(ei
->i_data
, inode
->i_size
,
4359 sizeof(ei
->i_data
) - 1);
4361 inode
->i_op
= &ext4_symlink_inode_operations
;
4362 ext4_set_aops(inode
);
4364 } else if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
) ||
4365 S_ISFIFO(inode
->i_mode
) || S_ISSOCK(inode
->i_mode
)) {
4366 inode
->i_op
= &ext4_special_inode_operations
;
4367 if (raw_inode
->i_block
[0])
4368 init_special_inode(inode
, inode
->i_mode
,
4369 old_decode_dev(le32_to_cpu(raw_inode
->i_block
[0])));
4371 init_special_inode(inode
, inode
->i_mode
,
4372 new_decode_dev(le32_to_cpu(raw_inode
->i_block
[1])));
4373 } else if (ino
== EXT4_BOOT_LOADER_INO
) {
4374 make_bad_inode(inode
);
4377 EXT4_ERROR_INODE(inode
, "bogus i_mode (%o)", inode
->i_mode
);
4381 ext4_set_inode_flags(inode
);
4382 unlock_new_inode(inode
);
4388 return ERR_PTR(ret
);
4391 static int ext4_inode_blocks_set(handle_t
*handle
,
4392 struct ext4_inode
*raw_inode
,
4393 struct ext4_inode_info
*ei
)
4395 struct inode
*inode
= &(ei
->vfs_inode
);
4396 u64 i_blocks
= inode
->i_blocks
;
4397 struct super_block
*sb
= inode
->i_sb
;
4399 if (i_blocks
<= ~0U) {
4401 * i_blocks can be represented in a 32 bit variable
4402 * as multiple of 512 bytes
4404 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4405 raw_inode
->i_blocks_high
= 0;
4406 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4409 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_HUGE_FILE
))
4412 if (i_blocks
<= 0xffffffffffffULL
) {
4414 * i_blocks can be represented in a 48 bit variable
4415 * as multiple of 512 bytes
4417 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4418 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4419 ext4_clear_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4421 ext4_set_inode_flag(inode
, EXT4_INODE_HUGE_FILE
);
4422 /* i_block is stored in file system block size */
4423 i_blocks
= i_blocks
>> (inode
->i_blkbits
- 9);
4424 raw_inode
->i_blocks_lo
= cpu_to_le32(i_blocks
);
4425 raw_inode
->i_blocks_high
= cpu_to_le16(i_blocks
>> 32);
4431 * Post the struct inode info into an on-disk inode location in the
4432 * buffer-cache. This gobbles the caller's reference to the
4433 * buffer_head in the inode location struct.
4435 * The caller must have write access to iloc->bh.
4437 static int ext4_do_update_inode(handle_t
*handle
,
4438 struct inode
*inode
,
4439 struct ext4_iloc
*iloc
)
4441 struct ext4_inode
*raw_inode
= ext4_raw_inode(iloc
);
4442 struct ext4_inode_info
*ei
= EXT4_I(inode
);
4443 struct buffer_head
*bh
= iloc
->bh
;
4444 int err
= 0, rc
, block
;
4445 int need_datasync
= 0;
4449 /* For fields not not tracking in the in-memory inode,
4450 * initialise them to zero for new inodes. */
4451 if (ext4_test_inode_state(inode
, EXT4_STATE_NEW
))
4452 memset(raw_inode
, 0, EXT4_SB(inode
->i_sb
)->s_inode_size
);
4454 ext4_get_inode_flags(ei
);
4455 raw_inode
->i_mode
= cpu_to_le16(inode
->i_mode
);
4456 i_uid
= i_uid_read(inode
);
4457 i_gid
= i_gid_read(inode
);
4458 if (!(test_opt(inode
->i_sb
, NO_UID32
))) {
4459 raw_inode
->i_uid_low
= cpu_to_le16(low_16_bits(i_uid
));
4460 raw_inode
->i_gid_low
= cpu_to_le16(low_16_bits(i_gid
));
4462 * Fix up interoperability with old kernels. Otherwise, old inodes get
4463 * re-used with the upper 16 bits of the uid/gid intact
4466 raw_inode
->i_uid_high
=
4467 cpu_to_le16(high_16_bits(i_uid
));
4468 raw_inode
->i_gid_high
=
4469 cpu_to_le16(high_16_bits(i_gid
));
4471 raw_inode
->i_uid_high
= 0;
4472 raw_inode
->i_gid_high
= 0;
4475 raw_inode
->i_uid_low
= cpu_to_le16(fs_high2lowuid(i_uid
));
4476 raw_inode
->i_gid_low
= cpu_to_le16(fs_high2lowgid(i_gid
));
4477 raw_inode
->i_uid_high
= 0;
4478 raw_inode
->i_gid_high
= 0;
4480 raw_inode
->i_links_count
= cpu_to_le16(inode
->i_nlink
);
4482 EXT4_INODE_SET_XTIME(i_ctime
, inode
, raw_inode
);
4483 EXT4_INODE_SET_XTIME(i_mtime
, inode
, raw_inode
);
4484 EXT4_INODE_SET_XTIME(i_atime
, inode
, raw_inode
);
4485 EXT4_EINODE_SET_XTIME(i_crtime
, ei
, raw_inode
);
4487 if (ext4_inode_blocks_set(handle
, raw_inode
, ei
))
4489 raw_inode
->i_dtime
= cpu_to_le32(ei
->i_dtime
);
4490 raw_inode
->i_flags
= cpu_to_le32(ei
->i_flags
& 0xFFFFFFFF);
4491 if (EXT4_SB(inode
->i_sb
)->s_es
->s_creator_os
!=
4492 cpu_to_le32(EXT4_OS_HURD
))
4493 raw_inode
->i_file_acl_high
=
4494 cpu_to_le16(ei
->i_file_acl
>> 32);
4495 raw_inode
->i_file_acl_lo
= cpu_to_le32(ei
->i_file_acl
);
4496 if (ei
->i_disksize
!= ext4_isize(raw_inode
)) {
4497 ext4_isize_set(raw_inode
, ei
->i_disksize
);
4500 if (ei
->i_disksize
> 0x7fffffffULL
) {
4501 struct super_block
*sb
= inode
->i_sb
;
4502 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb
,
4503 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
) ||
4504 EXT4_SB(sb
)->s_es
->s_rev_level
==
4505 cpu_to_le32(EXT4_GOOD_OLD_REV
)) {
4506 /* If this is the first large file
4507 * created, add a flag to the superblock.
4509 err
= ext4_journal_get_write_access(handle
,
4510 EXT4_SB(sb
)->s_sbh
);
4513 ext4_update_dynamic_rev(sb
);
4514 EXT4_SET_RO_COMPAT_FEATURE(sb
,
4515 EXT4_FEATURE_RO_COMPAT_LARGE_FILE
);
4516 ext4_handle_sync(handle
);
4517 err
= ext4_handle_dirty_super(handle
, sb
);
4520 raw_inode
->i_generation
= cpu_to_le32(inode
->i_generation
);
4521 if (S_ISCHR(inode
->i_mode
) || S_ISBLK(inode
->i_mode
)) {
4522 if (old_valid_dev(inode
->i_rdev
)) {
4523 raw_inode
->i_block
[0] =
4524 cpu_to_le32(old_encode_dev(inode
->i_rdev
));
4525 raw_inode
->i_block
[1] = 0;
4527 raw_inode
->i_block
[0] = 0;
4528 raw_inode
->i_block
[1] =
4529 cpu_to_le32(new_encode_dev(inode
->i_rdev
));
4530 raw_inode
->i_block
[2] = 0;
4532 } else if (!ext4_has_inline_data(inode
)) {
4533 for (block
= 0; block
< EXT4_N_BLOCKS
; block
++)
4534 raw_inode
->i_block
[block
] = ei
->i_data
[block
];
4537 raw_inode
->i_disk_version
= cpu_to_le32(inode
->i_version
);
4538 if (ei
->i_extra_isize
) {
4539 if (EXT4_FITS_IN_INODE(raw_inode
, ei
, i_version_hi
))
4540 raw_inode
->i_version_hi
=
4541 cpu_to_le32(inode
->i_version
>> 32);
4542 raw_inode
->i_extra_isize
= cpu_to_le16(ei
->i_extra_isize
);
4545 ext4_inode_csum_set(inode
, raw_inode
, ei
);
4547 BUFFER_TRACE(bh
, "call ext4_handle_dirty_metadata");
4548 rc
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
4551 ext4_clear_inode_state(inode
, EXT4_STATE_NEW
);
4553 ext4_update_inode_fsync_trans(handle
, inode
, need_datasync
);
4556 ext4_std_error(inode
->i_sb
, err
);
4561 * ext4_write_inode()
4563 * We are called from a few places:
4565 * - Within generic_file_write() for O_SYNC files.
4566 * Here, there will be no transaction running. We wait for any running
4567 * transaction to commit.
4569 * - Within sys_sync(), kupdate and such.
4570 * We wait on commit, if tol to.
4572 * - Within prune_icache() (PF_MEMALLOC == true)
4573 * Here we simply return. We can't afford to block kswapd on the
4576 * In all cases it is actually safe for us to return without doing anything,
4577 * because the inode has been copied into a raw inode buffer in
4578 * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
4581 * Note that we are absolutely dependent upon all inode dirtiers doing the
4582 * right thing: they *must* call mark_inode_dirty() after dirtying info in
4583 * which we are interested.
4585 * It would be a bug for them to not do this. The code:
4587 * mark_inode_dirty(inode)
4589 * inode->i_size = expr;
4591 * is in error because a kswapd-driven write_inode() could occur while
4592 * `stuff()' is running, and the new i_size will be lost. Plus the inode
4593 * will no longer be on the superblock's dirty inode list.
4595 int ext4_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
4599 if (current
->flags
& PF_MEMALLOC
)
4602 if (EXT4_SB(inode
->i_sb
)->s_journal
) {
4603 if (ext4_journal_current_handle()) {
4604 jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
4609 if (wbc
->sync_mode
!= WB_SYNC_ALL
)
4612 err
= ext4_force_commit(inode
->i_sb
);
4614 struct ext4_iloc iloc
;
4616 err
= __ext4_get_inode_loc(inode
, &iloc
, 0);
4619 if (wbc
->sync_mode
== WB_SYNC_ALL
)
4620 sync_dirty_buffer(iloc
.bh
);
4621 if (buffer_req(iloc
.bh
) && !buffer_uptodate(iloc
.bh
)) {
4622 EXT4_ERROR_INODE_BLOCK(inode
, iloc
.bh
->b_blocknr
,
4623 "IO error syncing inode");
4632 * In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
4633 * buffers that are attached to a page stradding i_size and are undergoing
4634 * commit. In that case we have to wait for commit to finish and try again.
4636 static void ext4_wait_for_tail_page_commit(struct inode
*inode
)
4640 journal_t
*journal
= EXT4_SB(inode
->i_sb
)->s_journal
;
4641 tid_t commit_tid
= 0;
4644 offset
= inode
->i_size
& (PAGE_CACHE_SIZE
- 1);
4646 * All buffers in the last page remain valid? Then there's nothing to
4647 * do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
4650 if (offset
> PAGE_CACHE_SIZE
- (1 << inode
->i_blkbits
))
4653 page
= find_lock_page(inode
->i_mapping
,
4654 inode
->i_size
>> PAGE_CACHE_SHIFT
);
4657 ret
= __ext4_journalled_invalidatepage(page
, offset
);
4659 page_cache_release(page
);
4663 read_lock(&journal
->j_state_lock
);
4664 if (journal
->j_committing_transaction
)
4665 commit_tid
= journal
->j_committing_transaction
->t_tid
;
4666 read_unlock(&journal
->j_state_lock
);
4668 jbd2_log_wait_commit(journal
, commit_tid
);
4675 * Called from notify_change.
4677 * We want to trap VFS attempts to truncate the file as soon as
4678 * possible. In particular, we want to make sure that when the VFS
4679 * shrinks i_size, we put the inode on the orphan list and modify
4680 * i_disksize immediately, so that during the subsequent flushing of
4681 * dirty pages and freeing of disk blocks, we can guarantee that any
4682 * commit will leave the blocks being flushed in an unused state on
4683 * disk. (On recovery, the inode will get truncated and the blocks will
4684 * be freed, so we have a strong guarantee that no future commit will
4685 * leave these blocks visible to the user.)
4687 * Another thing we have to assure is that if we are in ordered mode
4688 * and inode is still attached to the committing transaction, we must
4689 * we start writeout of all the dirty pages which are being truncated.
4690 * This way we are sure that all the data written in the previous
4691 * transaction are already on disk (truncate waits for pages under
4694 * Called with inode->i_mutex down.
4696 int ext4_setattr(struct dentry
*dentry
, struct iattr
*attr
)
4698 struct inode
*inode
= dentry
->d_inode
;
4701 const unsigned int ia_valid
= attr
->ia_valid
;
4703 error
= inode_change_ok(inode
, attr
);
4707 if (is_quota_modification(inode
, attr
))
4708 dquot_initialize(inode
);
4709 if ((ia_valid
& ATTR_UID
&& !uid_eq(attr
->ia_uid
, inode
->i_uid
)) ||
4710 (ia_valid
& ATTR_GID
&& !gid_eq(attr
->ia_gid
, inode
->i_gid
))) {
4713 /* (user+group)*(old+new) structure, inode write (sb,
4714 * inode block, ? - but truncate inode update has it) */
4715 handle
= ext4_journal_start(inode
, EXT4_HT_QUOTA
,
4716 (EXT4_MAXQUOTAS_INIT_BLOCKS(inode
->i_sb
) +
4717 EXT4_MAXQUOTAS_DEL_BLOCKS(inode
->i_sb
)) + 3);
4718 if (IS_ERR(handle
)) {
4719 error
= PTR_ERR(handle
);
4722 error
= dquot_transfer(inode
, attr
);
4724 ext4_journal_stop(handle
);
4727 /* Update corresponding info in inode so that everything is in
4728 * one transaction */
4729 if (attr
->ia_valid
& ATTR_UID
)
4730 inode
->i_uid
= attr
->ia_uid
;
4731 if (attr
->ia_valid
& ATTR_GID
)
4732 inode
->i_gid
= attr
->ia_gid
;
4733 error
= ext4_mark_inode_dirty(handle
, inode
);
4734 ext4_journal_stop(handle
);
4737 if (attr
->ia_valid
& ATTR_SIZE
&& attr
->ia_size
!= inode
->i_size
) {
4739 loff_t oldsize
= inode
->i_size
;
4741 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
))) {
4742 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
4744 if (attr
->ia_size
> sbi
->s_bitmap_maxbytes
)
4748 if (IS_I_VERSION(inode
) && attr
->ia_size
!= inode
->i_size
)
4749 inode_inc_iversion(inode
);
4751 if (S_ISREG(inode
->i_mode
) &&
4752 (attr
->ia_size
< inode
->i_size
)) {
4753 if (ext4_should_order_data(inode
)) {
4754 error
= ext4_begin_ordered_truncate(inode
,
4759 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 3);
4760 if (IS_ERR(handle
)) {
4761 error
= PTR_ERR(handle
);
4764 if (ext4_handle_valid(handle
)) {
4765 error
= ext4_orphan_add(handle
, inode
);
4768 EXT4_I(inode
)->i_disksize
= attr
->ia_size
;
4769 rc
= ext4_mark_inode_dirty(handle
, inode
);
4772 ext4_journal_stop(handle
);
4774 ext4_orphan_del(NULL
, inode
);
4779 i_size_write(inode
, attr
->ia_size
);
4781 * Blocks are going to be removed from the inode. Wait
4782 * for dio in flight. Temporarily disable
4783 * dioread_nolock to prevent livelock.
4786 if (!ext4_should_journal_data(inode
)) {
4787 ext4_inode_block_unlocked_dio(inode
);
4788 inode_dio_wait(inode
);
4789 ext4_inode_resume_unlocked_dio(inode
);
4791 ext4_wait_for_tail_page_commit(inode
);
4794 * Truncate pagecache after we've waited for commit
4795 * in data=journal mode to make pages freeable.
4797 truncate_pagecache(inode
, oldsize
, inode
->i_size
);
4800 * We want to call ext4_truncate() even if attr->ia_size ==
4801 * inode->i_size for cases like truncation of fallocated space
4803 if (attr
->ia_valid
& ATTR_SIZE
)
4804 ext4_truncate(inode
);
4807 setattr_copy(inode
, attr
);
4808 mark_inode_dirty(inode
);
4812 * If the call to ext4_truncate failed to get a transaction handle at
4813 * all, we need to clean up the in-core orphan list manually.
4815 if (orphan
&& inode
->i_nlink
)
4816 ext4_orphan_del(NULL
, inode
);
4818 if (!rc
&& (ia_valid
& ATTR_MODE
))
4819 rc
= ext4_acl_chmod(inode
);
4822 ext4_std_error(inode
->i_sb
, error
);
4828 int ext4_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
4831 struct inode
*inode
;
4832 unsigned long long delalloc_blocks
;
4834 inode
= dentry
->d_inode
;
4835 generic_fillattr(inode
, stat
);
4838 * We can't update i_blocks if the block allocation is delayed
4839 * otherwise in the case of system crash before the real block
4840 * allocation is done, we will have i_blocks inconsistent with
4841 * on-disk file blocks.
4842 * We always keep i_blocks updated together with real
4843 * allocation. But to not confuse with user, stat
4844 * will return the blocks that include the delayed allocation
4845 * blocks for this file.
4847 delalloc_blocks
= EXT4_C2B(EXT4_SB(inode
->i_sb
),
4848 EXT4_I(inode
)->i_reserved_data_blocks
);
4850 stat
->blocks
+= delalloc_blocks
<< (inode
->i_sb
->s_blocksize_bits
-9);
4854 static int ext4_index_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
4856 if (!(ext4_test_inode_flag(inode
, EXT4_INODE_EXTENTS
)))
4857 return ext4_ind_trans_blocks(inode
, nrblocks
, chunk
);
4858 return ext4_ext_index_trans_blocks(inode
, nrblocks
, chunk
);
4862 * Account for index blocks, block groups bitmaps and block group
4863 * descriptor blocks if modify datablocks and index blocks
4864 * worse case, the indexs blocks spread over different block groups
4866 * If datablocks are discontiguous, they are possible to spread over
4867 * different block groups too. If they are contiguous, with flexbg,
4868 * they could still across block group boundary.
4870 * Also account for superblock, inode, quota and xattr blocks
4872 static int ext4_meta_trans_blocks(struct inode
*inode
, int nrblocks
, int chunk
)
4874 ext4_group_t groups
, ngroups
= ext4_get_groups_count(inode
->i_sb
);
4880 * How many index blocks need to touch to modify nrblocks?
4881 * The "Chunk" flag indicating whether the nrblocks is
4882 * physically contiguous on disk
4884 * For Direct IO and fallocate, they calls get_block to allocate
4885 * one single extent at a time, so they could set the "Chunk" flag
4887 idxblocks
= ext4_index_trans_blocks(inode
, nrblocks
, chunk
);
4892 * Now let's see how many group bitmaps and group descriptors need
4902 if (groups
> ngroups
)
4904 if (groups
> EXT4_SB(inode
->i_sb
)->s_gdb_count
)
4905 gdpblocks
= EXT4_SB(inode
->i_sb
)->s_gdb_count
;
4907 /* bitmaps and block group descriptor blocks */
4908 ret
+= groups
+ gdpblocks
;
4910 /* Blocks for super block, inode, quota and xattr blocks */
4911 ret
+= EXT4_META_TRANS_BLOCKS(inode
->i_sb
);
4917 * Calculate the total number of credits to reserve to fit
4918 * the modification of a single pages into a single transaction,
4919 * which may include multiple chunks of block allocations.
4921 * This could be called via ext4_write_begin()
4923 * We need to consider the worse case, when
4924 * one new block per extent.
4926 int ext4_writepage_trans_blocks(struct inode
*inode
)
4928 int bpp
= ext4_journal_blocks_per_page(inode
);
4931 ret
= ext4_meta_trans_blocks(inode
, bpp
, 0);
4933 /* Account for data blocks for journalled mode */
4934 if (ext4_should_journal_data(inode
))
4940 * Calculate the journal credits for a chunk of data modification.
4942 * This is called from DIO, fallocate or whoever calling
4943 * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
4945 * journal buffers for data blocks are not included here, as DIO
4946 * and fallocate do no need to journal data buffers.
4948 int ext4_chunk_trans_blocks(struct inode
*inode
, int nrblocks
)
4950 return ext4_meta_trans_blocks(inode
, nrblocks
, 1);
4954 * The caller must have previously called ext4_reserve_inode_write().
4955 * Give this, we know that the caller already has write access to iloc->bh.
4957 int ext4_mark_iloc_dirty(handle_t
*handle
,
4958 struct inode
*inode
, struct ext4_iloc
*iloc
)
4962 if (IS_I_VERSION(inode
))
4963 inode_inc_iversion(inode
);
4965 /* the do_update_inode consumes one bh->b_count */
4968 /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
4969 err
= ext4_do_update_inode(handle
, inode
, iloc
);
4975 * On success, We end up with an outstanding reference count against
4976 * iloc->bh. This _must_ be cleaned up later.
4980 ext4_reserve_inode_write(handle_t
*handle
, struct inode
*inode
,
4981 struct ext4_iloc
*iloc
)
4985 err
= ext4_get_inode_loc(inode
, iloc
);
4987 BUFFER_TRACE(iloc
->bh
, "get_write_access");
4988 err
= ext4_journal_get_write_access(handle
, iloc
->bh
);
4994 ext4_std_error(inode
->i_sb
, err
);
4999 * Expand an inode by new_extra_isize bytes.
5000 * Returns 0 on success or negative error number on failure.
5002 static int ext4_expand_extra_isize(struct inode
*inode
,
5003 unsigned int new_extra_isize
,
5004 struct ext4_iloc iloc
,
5007 struct ext4_inode
*raw_inode
;
5008 struct ext4_xattr_ibody_header
*header
;
5010 if (EXT4_I(inode
)->i_extra_isize
>= new_extra_isize
)
5013 raw_inode
= ext4_raw_inode(&iloc
);
5015 header
= IHDR(inode
, raw_inode
);
5017 /* No extended attributes present */
5018 if (!ext4_test_inode_state(inode
, EXT4_STATE_XATTR
) ||
5019 header
->h_magic
!= cpu_to_le32(EXT4_XATTR_MAGIC
)) {
5020 memset((void *)raw_inode
+ EXT4_GOOD_OLD_INODE_SIZE
, 0,
5022 EXT4_I(inode
)->i_extra_isize
= new_extra_isize
;
5026 /* try to expand with EAs present */
5027 return ext4_expand_extra_isize_ea(inode
, new_extra_isize
,
5032 * What we do here is to mark the in-core inode as clean with respect to inode
5033 * dirtiness (it may still be data-dirty).
5034 * This means that the in-core inode may be reaped by prune_icache
5035 * without having to perform any I/O. This is a very good thing,
5036 * because *any* task may call prune_icache - even ones which
5037 * have a transaction open against a different journal.
5039 * Is this cheating? Not really. Sure, we haven't written the
5040 * inode out, but prune_icache isn't a user-visible syncing function.
5041 * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
5042 * we start and wait on commits.
5044 int ext4_mark_inode_dirty(handle_t
*handle
, struct inode
*inode
)
5046 struct ext4_iloc iloc
;
5047 struct ext4_sb_info
*sbi
= EXT4_SB(inode
->i_sb
);
5048 static unsigned int mnt_count
;
5052 trace_ext4_mark_inode_dirty(inode
, _RET_IP_
);
5053 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
5054 if (ext4_handle_valid(handle
) &&
5055 EXT4_I(inode
)->i_extra_isize
< sbi
->s_want_extra_isize
&&
5056 !ext4_test_inode_state(inode
, EXT4_STATE_NO_EXPAND
)) {
5058 * We need extra buffer credits since we may write into EA block
5059 * with this same handle. If journal_extend fails, then it will
5060 * only result in a minor loss of functionality for that inode.
5061 * If this is felt to be critical, then e2fsck should be run to
5062 * force a large enough s_min_extra_isize.
5064 if ((jbd2_journal_extend(handle
,
5065 EXT4_DATA_TRANS_BLOCKS(inode
->i_sb
))) == 0) {
5066 ret
= ext4_expand_extra_isize(inode
,
5067 sbi
->s_want_extra_isize
,
5070 ext4_set_inode_state(inode
,
5071 EXT4_STATE_NO_EXPAND
);
5073 le16_to_cpu(sbi
->s_es
->s_mnt_count
)) {
5074 ext4_warning(inode
->i_sb
,
5075 "Unable to expand inode %lu. Delete"
5076 " some EAs or run e2fsck.",
5079 le16_to_cpu(sbi
->s_es
->s_mnt_count
);
5085 err
= ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
5090 * ext4_dirty_inode() is called from __mark_inode_dirty()
5092 * We're really interested in the case where a file is being extended.
5093 * i_size has been changed by generic_commit_write() and we thus need
5094 * to include the updated inode in the current transaction.
5096 * Also, dquot_alloc_block() will always dirty the inode when blocks
5097 * are allocated to the file.
5099 * If the inode is marked synchronous, we don't honour that here - doing
5100 * so would cause a commit on atime updates, which we don't bother doing.
5101 * We handle synchronous inodes at the highest possible level.
5103 void ext4_dirty_inode(struct inode
*inode
, int flags
)
5107 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 2);
5111 ext4_mark_inode_dirty(handle
, inode
);
5113 ext4_journal_stop(handle
);
5120 * Bind an inode's backing buffer_head into this transaction, to prevent
5121 * it from being flushed to disk early. Unlike
5122 * ext4_reserve_inode_write, this leaves behind no bh reference and
5123 * returns no iloc structure, so the caller needs to repeat the iloc
5124 * lookup to mark the inode dirty later.
5126 static int ext4_pin_inode(handle_t
*handle
, struct inode
*inode
)
5128 struct ext4_iloc iloc
;
5132 err
= ext4_get_inode_loc(inode
, &iloc
);
5134 BUFFER_TRACE(iloc
.bh
, "get_write_access");
5135 err
= jbd2_journal_get_write_access(handle
, iloc
.bh
);
5137 err
= ext4_handle_dirty_metadata(handle
,
5143 ext4_std_error(inode
->i_sb
, err
);
5148 int ext4_change_inode_journal_flag(struct inode
*inode
, int val
)
5155 * We have to be very careful here: changing a data block's
5156 * journaling status dynamically is dangerous. If we write a
5157 * data block to the journal, change the status and then delete
5158 * that block, we risk forgetting to revoke the old log record
5159 * from the journal and so a subsequent replay can corrupt data.
5160 * So, first we make sure that the journal is empty and that
5161 * nobody is changing anything.
5164 journal
= EXT4_JOURNAL(inode
);
5167 if (is_journal_aborted(journal
))
5169 /* We have to allocate physical blocks for delalloc blocks
5170 * before flushing journal. otherwise delalloc blocks can not
5171 * be allocated any more. even more truncate on delalloc blocks
5172 * could trigger BUG by flushing delalloc blocks in journal.
5173 * There is no delalloc block in non-journal data mode.
5175 if (val
&& test_opt(inode
->i_sb
, DELALLOC
)) {
5176 err
= ext4_alloc_da_blocks(inode
);
5181 /* Wait for all existing dio workers */
5182 ext4_inode_block_unlocked_dio(inode
);
5183 inode_dio_wait(inode
);
5185 jbd2_journal_lock_updates(journal
);
5188 * OK, there are no updates running now, and all cached data is
5189 * synced to disk. We are now in a completely consistent state
5190 * which doesn't have anything in the journal, and we know that
5191 * no filesystem updates are running, so it is safe to modify
5192 * the inode's in-core data-journaling state flag now.
5196 ext4_set_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5198 jbd2_journal_flush(journal
);
5199 ext4_clear_inode_flag(inode
, EXT4_INODE_JOURNAL_DATA
);
5201 ext4_set_aops(inode
);
5203 jbd2_journal_unlock_updates(journal
);
5204 ext4_inode_resume_unlocked_dio(inode
);
5206 /* Finally we can mark the inode as dirty. */
5208 handle
= ext4_journal_start(inode
, EXT4_HT_INODE
, 1);
5210 return PTR_ERR(handle
);
5212 err
= ext4_mark_inode_dirty(handle
, inode
);
5213 ext4_handle_sync(handle
);
5214 ext4_journal_stop(handle
);
5215 ext4_std_error(inode
->i_sb
, err
);
5220 static int ext4_bh_unmapped(handle_t
*handle
, struct buffer_head
*bh
)
5222 return !buffer_mapped(bh
);
5225 int ext4_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
5227 struct page
*page
= vmf
->page
;
5231 struct file
*file
= vma
->vm_file
;
5232 struct inode
*inode
= file_inode(file
);
5233 struct address_space
*mapping
= inode
->i_mapping
;
5235 get_block_t
*get_block
;
5238 sb_start_pagefault(inode
->i_sb
);
5239 file_update_time(vma
->vm_file
);
5240 /* Delalloc case is easy... */
5241 if (test_opt(inode
->i_sb
, DELALLOC
) &&
5242 !ext4_should_journal_data(inode
) &&
5243 !ext4_nonda_switch(inode
->i_sb
)) {
5245 ret
= __block_page_mkwrite(vma
, vmf
,
5246 ext4_da_get_block_prep
);
5247 } while (ret
== -ENOSPC
&&
5248 ext4_should_retry_alloc(inode
->i_sb
, &retries
));
5253 size
= i_size_read(inode
);
5254 /* Page got truncated from under us? */
5255 if (page
->mapping
!= mapping
|| page_offset(page
) > size
) {
5257 ret
= VM_FAULT_NOPAGE
;
5261 if (page
->index
== size
>> PAGE_CACHE_SHIFT
)
5262 len
= size
& ~PAGE_CACHE_MASK
;
5264 len
= PAGE_CACHE_SIZE
;
5266 * Return if we have all the buffers mapped. This avoids the need to do
5267 * journal_start/journal_stop which can block and take a long time
5269 if (page_has_buffers(page
)) {
5270 if (!ext4_walk_page_buffers(NULL
, page_buffers(page
),
5272 ext4_bh_unmapped
)) {
5273 /* Wait so that we don't change page under IO */
5274 wait_for_stable_page(page
);
5275 ret
= VM_FAULT_LOCKED
;
5280 /* OK, we need to fill the hole... */
5281 if (ext4_should_dioread_nolock(inode
))
5282 get_block
= ext4_get_block_write
;
5284 get_block
= ext4_get_block
;
5286 handle
= ext4_journal_start(inode
, EXT4_HT_WRITE_PAGE
,
5287 ext4_writepage_trans_blocks(inode
));
5288 if (IS_ERR(handle
)) {
5289 ret
= VM_FAULT_SIGBUS
;
5292 ret
= __block_page_mkwrite(vma
, vmf
, get_block
);
5293 if (!ret
&& ext4_should_journal_data(inode
)) {
5294 if (ext4_walk_page_buffers(handle
, page_buffers(page
), 0,
5295 PAGE_CACHE_SIZE
, NULL
, do_journal_get_write_access
)) {
5297 ret
= VM_FAULT_SIGBUS
;
5298 ext4_journal_stop(handle
);
5301 ext4_set_inode_state(inode
, EXT4_STATE_JDATA
);
5303 ext4_journal_stop(handle
);
5304 if (ret
== -ENOSPC
&& ext4_should_retry_alloc(inode
->i_sb
, &retries
))
5307 ret
= block_page_mkwrite_return(ret
);
5309 sb_end_pagefault(inode
->i_sb
);