4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/f2fs_fs.h>
13 #include <linux/buffer_head.h>
14 #include <linux/mpage.h>
15 #include <linux/writeback.h>
16 #include <linux/backing-dev.h>
17 #include <linux/blkdev.h>
18 #include <linux/bio.h>
25 * Lock ordering for the change of data block address:
28 * update block addresses in the node page
30 static void __set_data_blkaddr(struct dnode_of_data
*dn
, block_t new_addr
)
34 struct page
*node_page
= dn
->node_page
;
35 unsigned int ofs_in_node
= dn
->ofs_in_node
;
37 wait_on_page_writeback(node_page
);
39 rn
= (struct f2fs_node
*)page_address(node_page
);
41 /* Get physical address of data block */
42 addr_array
= blkaddr_in_node(rn
);
43 addr_array
[ofs_in_node
] = cpu_to_le32(new_addr
);
44 set_page_dirty(node_page
);
47 int reserve_new_block(struct dnode_of_data
*dn
)
49 struct f2fs_sb_info
*sbi
= F2FS_SB(dn
->inode
->i_sb
);
51 if (is_inode_flag_set(F2FS_I(dn
->inode
), FI_NO_ALLOC
))
53 if (!inc_valid_block_count(sbi
, dn
->inode
, 1))
56 __set_data_blkaddr(dn
, NEW_ADDR
);
57 dn
->data_blkaddr
= NEW_ADDR
;
62 static int check_extent_cache(struct inode
*inode
, pgoff_t pgofs
,
63 struct buffer_head
*bh_result
)
65 struct f2fs_inode_info
*fi
= F2FS_I(inode
);
66 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
67 pgoff_t start_fofs
, end_fofs
;
68 block_t start_blkaddr
;
70 read_lock(&fi
->ext
.ext_lock
);
71 if (fi
->ext
.len
== 0) {
72 read_unlock(&fi
->ext
.ext_lock
);
77 start_fofs
= fi
->ext
.fofs
;
78 end_fofs
= fi
->ext
.fofs
+ fi
->ext
.len
- 1;
79 start_blkaddr
= fi
->ext
.blk_addr
;
81 if (pgofs
>= start_fofs
&& pgofs
<= end_fofs
) {
82 unsigned int blkbits
= inode
->i_sb
->s_blocksize_bits
;
85 clear_buffer_new(bh_result
);
86 map_bh(bh_result
, inode
->i_sb
,
87 start_blkaddr
+ pgofs
- start_fofs
);
88 count
= end_fofs
- pgofs
+ 1;
89 if (count
< (UINT_MAX
>> blkbits
))
90 bh_result
->b_size
= (count
<< blkbits
);
92 bh_result
->b_size
= UINT_MAX
;
95 read_unlock(&fi
->ext
.ext_lock
);
98 read_unlock(&fi
->ext
.ext_lock
);
102 void update_extent_cache(block_t blk_addr
, struct dnode_of_data
*dn
)
104 struct f2fs_inode_info
*fi
= F2FS_I(dn
->inode
);
105 pgoff_t fofs
, start_fofs
, end_fofs
;
106 block_t start_blkaddr
, end_blkaddr
;
108 BUG_ON(blk_addr
== NEW_ADDR
);
109 fofs
= start_bidx_of_node(ofs_of_node(dn
->node_page
)) + dn
->ofs_in_node
;
111 /* Update the page address in the parent node */
112 __set_data_blkaddr(dn
, blk_addr
);
114 write_lock(&fi
->ext
.ext_lock
);
116 start_fofs
= fi
->ext
.fofs
;
117 end_fofs
= fi
->ext
.fofs
+ fi
->ext
.len
- 1;
118 start_blkaddr
= fi
->ext
.blk_addr
;
119 end_blkaddr
= fi
->ext
.blk_addr
+ fi
->ext
.len
- 1;
121 /* Drop and initialize the matched extent */
122 if (fi
->ext
.len
== 1 && fofs
== start_fofs
)
126 if (fi
->ext
.len
== 0) {
127 if (blk_addr
!= NULL_ADDR
) {
129 fi
->ext
.blk_addr
= blk_addr
;
136 if (fofs
== start_fofs
- 1 && blk_addr
== start_blkaddr
- 1) {
144 if (fofs
== end_fofs
+ 1 && blk_addr
== end_blkaddr
+ 1) {
149 /* Split the existing extent */
150 if (fi
->ext
.len
> 1 &&
151 fofs
>= start_fofs
&& fofs
<= end_fofs
) {
152 if ((end_fofs
- fofs
) < (fi
->ext
.len
>> 1)) {
153 fi
->ext
.len
= fofs
- start_fofs
;
155 fi
->ext
.fofs
= fofs
+ 1;
156 fi
->ext
.blk_addr
= start_blkaddr
+
157 fofs
- start_fofs
+ 1;
158 fi
->ext
.len
-= fofs
- start_fofs
+ 1;
162 write_unlock(&fi
->ext
.ext_lock
);
166 write_unlock(&fi
->ext
.ext_lock
);
171 struct page
*find_data_page(struct inode
*inode
, pgoff_t index
)
173 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
174 struct address_space
*mapping
= inode
->i_mapping
;
175 struct dnode_of_data dn
;
179 page
= find_get_page(mapping
, index
);
180 if (page
&& PageUptodate(page
))
182 f2fs_put_page(page
, 0);
184 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
185 err
= get_dnode_of_data(&dn
, index
, RDONLY_NODE
);
190 if (dn
.data_blkaddr
== NULL_ADDR
)
191 return ERR_PTR(-ENOENT
);
193 /* By fallocate(), there is no cached page, but with NEW_ADDR */
194 if (dn
.data_blkaddr
== NEW_ADDR
)
195 return ERR_PTR(-EINVAL
);
197 page
= grab_cache_page(mapping
, index
);
199 return ERR_PTR(-ENOMEM
);
201 err
= f2fs_readpage(sbi
, page
, dn
.data_blkaddr
, READ_SYNC
);
203 f2fs_put_page(page
, 1);
211 * If it tries to access a hole, return an error.
212 * Because, the callers, functions in dir.c and GC, should be able to know
213 * whether this page exists or not.
215 struct page
*get_lock_data_page(struct inode
*inode
, pgoff_t index
)
217 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
218 struct address_space
*mapping
= inode
->i_mapping
;
219 struct dnode_of_data dn
;
223 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
224 err
= get_dnode_of_data(&dn
, index
, RDONLY_NODE
);
229 if (dn
.data_blkaddr
== NULL_ADDR
)
230 return ERR_PTR(-ENOENT
);
232 page
= grab_cache_page(mapping
, index
);
234 return ERR_PTR(-ENOMEM
);
236 if (PageUptodate(page
))
239 BUG_ON(dn
.data_blkaddr
== NEW_ADDR
);
240 BUG_ON(dn
.data_blkaddr
== NULL_ADDR
);
242 err
= f2fs_readpage(sbi
, page
, dn
.data_blkaddr
, READ_SYNC
);
244 f2fs_put_page(page
, 1);
251 * Caller ensures that this data page is never allocated.
252 * A new zero-filled data page is allocated in the page cache.
254 struct page
*get_new_data_page(struct inode
*inode
, pgoff_t index
,
257 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
258 struct address_space
*mapping
= inode
->i_mapping
;
260 struct dnode_of_data dn
;
263 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
264 err
= get_dnode_of_data(&dn
, index
, 0);
268 if (dn
.data_blkaddr
== NULL_ADDR
) {
269 if (reserve_new_block(&dn
)) {
271 return ERR_PTR(-ENOSPC
);
276 page
= grab_cache_page(mapping
, index
);
278 return ERR_PTR(-ENOMEM
);
280 if (PageUptodate(page
))
283 if (dn
.data_blkaddr
== NEW_ADDR
) {
284 zero_user_segment(page
, 0, PAGE_CACHE_SIZE
);
286 err
= f2fs_readpage(sbi
, page
, dn
.data_blkaddr
, READ_SYNC
);
288 f2fs_put_page(page
, 1);
292 SetPageUptodate(page
);
295 i_size_read(inode
) < ((index
+ 1) << PAGE_CACHE_SHIFT
)) {
296 i_size_write(inode
, ((index
+ 1) << PAGE_CACHE_SHIFT
));
297 mark_inode_dirty_sync(inode
);
302 static void read_end_io(struct bio
*bio
, int err
)
304 const int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
305 struct bio_vec
*bvec
= bio
->bi_io_vec
+ bio
->bi_vcnt
- 1;
308 struct page
*page
= bvec
->bv_page
;
310 if (--bvec
>= bio
->bi_io_vec
)
311 prefetchw(&bvec
->bv_page
->flags
);
314 SetPageUptodate(page
);
316 ClearPageUptodate(page
);
320 } while (bvec
>= bio
->bi_io_vec
);
321 kfree(bio
->bi_private
);
326 * Fill the locked page with data located in the block address.
327 * Read operation is synchronous, and caller must unlock the page.
329 int f2fs_readpage(struct f2fs_sb_info
*sbi
, struct page
*page
,
330 block_t blk_addr
, int type
)
332 struct block_device
*bdev
= sbi
->sb
->s_bdev
;
333 bool sync
= (type
== READ_SYNC
);
336 /* This page can be already read by other threads */
337 if (PageUptodate(page
)) {
343 down_read(&sbi
->bio_sem
);
345 /* Allocate a new bio */
346 bio
= f2fs_bio_alloc(bdev
, blk_addr
<< (sbi
->log_blocksize
- 9),
347 1, GFP_NOFS
| __GFP_HIGH
);
349 /* Initialize the bio */
350 bio
->bi_end_io
= read_end_io
;
351 if (bio_add_page(bio
, page
, PAGE_CACHE_SIZE
, 0) < PAGE_CACHE_SIZE
) {
352 kfree(bio
->bi_private
);
354 up_read(&sbi
->bio_sem
);
358 submit_bio(type
, bio
);
359 up_read(&sbi
->bio_sem
);
361 /* wait for read completion if sync */
371 * This function should be used by the data read flow only where it
372 * does not check the "create" flag that indicates block allocation.
373 * The reason for this special functionality is to exploit VFS readahead
376 static int get_data_block_ro(struct inode
*inode
, sector_t iblock
,
377 struct buffer_head
*bh_result
, int create
)
379 unsigned int blkbits
= inode
->i_sb
->s_blocksize_bits
;
380 unsigned maxblocks
= bh_result
->b_size
>> blkbits
;
381 struct dnode_of_data dn
;
385 /* Get the page offset from the block offset(iblock) */
386 pgofs
= (pgoff_t
)(iblock
>> (PAGE_CACHE_SHIFT
- blkbits
));
388 if (check_extent_cache(inode
, pgofs
, bh_result
))
391 /* When reading holes, we need its node page */
392 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
393 err
= get_dnode_of_data(&dn
, pgofs
, RDONLY_NODE
);
395 return (err
== -ENOENT
) ? 0 : err
;
397 /* It does not support data allocation */
400 if (dn
.data_blkaddr
!= NEW_ADDR
&& dn
.data_blkaddr
!= NULL_ADDR
) {
402 unsigned int end_offset
;
404 end_offset
= IS_INODE(dn
.node_page
) ?
408 clear_buffer_new(bh_result
);
410 /* Give more consecutive addresses for the read ahead */
411 for (i
= 0; i
< end_offset
- dn
.ofs_in_node
; i
++)
412 if (((datablock_addr(dn
.node_page
,
414 != (dn
.data_blkaddr
+ i
)) || maxblocks
== i
)
416 map_bh(bh_result
, inode
->i_sb
, dn
.data_blkaddr
);
417 bh_result
->b_size
= (i
<< blkbits
);
423 static int f2fs_read_data_page(struct file
*file
, struct page
*page
)
425 return mpage_readpage(page
, get_data_block_ro
);
428 static int f2fs_read_data_pages(struct file
*file
,
429 struct address_space
*mapping
,
430 struct list_head
*pages
, unsigned nr_pages
)
432 return mpage_readpages(mapping
, pages
, nr_pages
, get_data_block_ro
);
435 int do_write_data_page(struct page
*page
)
437 struct inode
*inode
= page
->mapping
->host
;
438 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
439 block_t old_blk_addr
, new_blk_addr
;
440 struct dnode_of_data dn
;
443 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
444 err
= get_dnode_of_data(&dn
, page
->index
, RDONLY_NODE
);
448 old_blk_addr
= dn
.data_blkaddr
;
450 /* This page is already truncated */
451 if (old_blk_addr
== NULL_ADDR
)
454 set_page_writeback(page
);
457 * If current allocation needs SSR,
458 * it had better in-place writes for updated data.
460 if (old_blk_addr
!= NEW_ADDR
&& !is_cold_data(page
) &&
461 need_inplace_update(inode
)) {
462 rewrite_data_page(F2FS_SB(inode
->i_sb
), page
,
465 write_data_page(inode
, page
, &dn
,
466 old_blk_addr
, &new_blk_addr
);
467 update_extent_cache(new_blk_addr
, &dn
);
468 F2FS_I(inode
)->data_version
=
469 le64_to_cpu(F2FS_CKPT(sbi
)->checkpoint_ver
);
476 static int f2fs_write_data_page(struct page
*page
,
477 struct writeback_control
*wbc
)
479 struct inode
*inode
= page
->mapping
->host
;
480 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
481 loff_t i_size
= i_size_read(inode
);
482 const pgoff_t end_index
= ((unsigned long long) i_size
)
487 if (page
->index
< end_index
)
491 * If the offset is out-of-range of file size,
492 * this page does not have to be written to disk.
494 offset
= i_size
& (PAGE_CACHE_SIZE
- 1);
495 if ((page
->index
>= end_index
+ 1) || !offset
) {
496 if (S_ISDIR(inode
->i_mode
)) {
497 dec_page_count(sbi
, F2FS_DIRTY_DENTS
);
498 inode_dec_dirty_dents(inode
);
503 zero_user_segment(page
, offset
, PAGE_CACHE_SIZE
);
508 if (wbc
->for_reclaim
&& !S_ISDIR(inode
->i_mode
) && !is_cold_data(page
))
511 mutex_lock_op(sbi
, DATA_WRITE
);
512 if (S_ISDIR(inode
->i_mode
)) {
513 dec_page_count(sbi
, F2FS_DIRTY_DENTS
);
514 inode_dec_dirty_dents(inode
);
516 err
= do_write_data_page(page
);
517 if (err
&& err
!= -ENOENT
) {
518 wbc
->pages_skipped
++;
519 set_page_dirty(page
);
521 mutex_unlock_op(sbi
, DATA_WRITE
);
523 if (wbc
->for_reclaim
)
524 f2fs_submit_bio(sbi
, DATA
, true);
529 clear_cold_data(page
);
532 if (!wbc
->for_reclaim
&& !S_ISDIR(inode
->i_mode
))
533 f2fs_balance_fs(sbi
);
538 return (err
== -ENOENT
) ? 0 : err
;
541 wbc
->pages_skipped
++;
542 set_page_dirty(page
);
543 return AOP_WRITEPAGE_ACTIVATE
;
546 #define MAX_DESIRED_PAGES_WP 4096
548 static int f2fs_write_data_pages(struct address_space
*mapping
,
549 struct writeback_control
*wbc
)
551 struct inode
*inode
= mapping
->host
;
552 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
554 long excess_nrtw
= 0, desired_nrtw
;
556 if (wbc
->nr_to_write
< MAX_DESIRED_PAGES_WP
) {
557 desired_nrtw
= MAX_DESIRED_PAGES_WP
;
558 excess_nrtw
= desired_nrtw
- wbc
->nr_to_write
;
559 wbc
->nr_to_write
= desired_nrtw
;
562 if (!S_ISDIR(inode
->i_mode
))
563 mutex_lock(&sbi
->writepages
);
564 ret
= generic_writepages(mapping
, wbc
);
565 if (!S_ISDIR(inode
->i_mode
))
566 mutex_unlock(&sbi
->writepages
);
567 f2fs_submit_bio(sbi
, DATA
, (wbc
->sync_mode
== WB_SYNC_ALL
));
569 remove_dirty_dir_inode(inode
);
571 wbc
->nr_to_write
-= excess_nrtw
;
575 static int f2fs_write_begin(struct file
*file
, struct address_space
*mapping
,
576 loff_t pos
, unsigned len
, unsigned flags
,
577 struct page
**pagep
, void **fsdata
)
579 struct inode
*inode
= mapping
->host
;
580 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
582 pgoff_t index
= ((unsigned long long) pos
) >> PAGE_CACHE_SHIFT
;
583 struct dnode_of_data dn
;
586 /* for nobh_write_end */
589 f2fs_balance_fs(sbi
);
591 page
= grab_cache_page_write_begin(mapping
, index
, flags
);
596 mutex_lock_op(sbi
, DATA_NEW
);
598 set_new_dnode(&dn
, inode
, NULL
, NULL
, 0);
599 err
= get_dnode_of_data(&dn
, index
, 0);
601 mutex_unlock_op(sbi
, DATA_NEW
);
602 f2fs_put_page(page
, 1);
606 if (dn
.data_blkaddr
== NULL_ADDR
) {
607 err
= reserve_new_block(&dn
);
610 mutex_unlock_op(sbi
, DATA_NEW
);
611 f2fs_put_page(page
, 1);
617 mutex_unlock_op(sbi
, DATA_NEW
);
619 if ((len
== PAGE_CACHE_SIZE
) || PageUptodate(page
))
622 if ((pos
& PAGE_CACHE_MASK
) >= i_size_read(inode
)) {
623 unsigned start
= pos
& (PAGE_CACHE_SIZE
- 1);
624 unsigned end
= start
+ len
;
626 /* Reading beyond i_size is simple: memset to zero */
627 zero_user_segments(page
, 0, start
, end
, PAGE_CACHE_SIZE
);
631 if (dn
.data_blkaddr
== NEW_ADDR
) {
632 zero_user_segment(page
, 0, PAGE_CACHE_SIZE
);
634 err
= f2fs_readpage(sbi
, page
, dn
.data_blkaddr
, READ_SYNC
);
636 f2fs_put_page(page
, 1);
640 SetPageUptodate(page
);
641 clear_cold_data(page
);
645 static ssize_t
f2fs_direct_IO(int rw
, struct kiocb
*iocb
,
646 const struct iovec
*iov
, loff_t offset
, unsigned long nr_segs
)
648 struct file
*file
= iocb
->ki_filp
;
649 struct inode
*inode
= file
->f_mapping
->host
;
654 /* Needs synchronization with the cleaner */
655 return blockdev_direct_IO(rw
, iocb
, inode
, iov
, offset
, nr_segs
,
659 static void f2fs_invalidate_data_page(struct page
*page
, unsigned long offset
)
661 struct inode
*inode
= page
->mapping
->host
;
662 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
663 if (S_ISDIR(inode
->i_mode
) && PageDirty(page
)) {
664 dec_page_count(sbi
, F2FS_DIRTY_DENTS
);
665 inode_dec_dirty_dents(inode
);
667 ClearPagePrivate(page
);
670 static int f2fs_release_data_page(struct page
*page
, gfp_t wait
)
672 ClearPagePrivate(page
);
676 static int f2fs_set_data_page_dirty(struct page
*page
)
678 struct address_space
*mapping
= page
->mapping
;
679 struct inode
*inode
= mapping
->host
;
681 SetPageUptodate(page
);
682 if (!PageDirty(page
)) {
683 __set_page_dirty_nobuffers(page
);
684 set_dirty_dir_page(inode
, page
);
690 const struct address_space_operations f2fs_dblock_aops
= {
691 .readpage
= f2fs_read_data_page
,
692 .readpages
= f2fs_read_data_pages
,
693 .writepage
= f2fs_write_data_page
,
694 .writepages
= f2fs_write_data_pages
,
695 .write_begin
= f2fs_write_begin
,
696 .write_end
= nobh_write_end
,
697 .set_page_dirty
= f2fs_set_data_page_dirty
,
698 .invalidatepage
= f2fs_invalidate_data_page
,
699 .releasepage
= f2fs_release_data_page
,
700 .direct_IO
= f2fs_direct_IO
,