projects / GitHub / exynos8895 / android_kernel_samsung_universal8895.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
f2fs: fix endian conversion bugs reported by sparse
[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / fs / f2fs / data.c
CommitLineData
eb47b800
JK		 1/**
2 * fs/f2fs/data.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
6 *
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.
10 */
11#include <linux/fs.h>
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>
19
20#include "f2fs.h"
21#include "node.h"
22#include "segment.h"
23
24/**
25 * Lock ordering for the change of data block address:
26 * ->data_page
27 * ->node_page
28 * update block addresses in the node page
29 */
30static void __set_data_blkaddr(struct dnode_of_data *dn, block_t new_addr)
31{
32 struct f2fs_node *rn;
33 __le32 *addr_array;
34 struct page *node_page = dn->node_page;
35 unsigned int ofs_in_node = dn->ofs_in_node;
36
37 wait_on_page_writeback(node_page);
38
39 rn = (struct f2fs_node *)page_address(node_page);
40
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);
45}
46
47int reserve_new_block(struct dnode_of_data *dn)
48{
49 struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
50
51 if (is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC))
52 return -EPERM;
53 if (!inc_valid_block_count(sbi, dn->inode, 1))
54 return -ENOSPC;
55
56 __set_data_blkaddr(dn, NEW_ADDR);
57 dn->data_blkaddr = NEW_ADDR;
58 sync_inode_page(dn);
59 return 0;
60}
61
62static int check_extent_cache(struct inode *inode, pgoff_t pgofs,
63 struct buffer_head *bh_result)
64{
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;
69
70 read_lock(&fi->ext.ext_lock);
71 if (fi->ext.len == 0) {
72 read_unlock(&fi->ext.ext_lock);
73 return 0;
74 }
75
76 sbi->total_hit_ext++;
77 start_fofs = fi->ext.fofs;
78 end_fofs = fi->ext.fofs + fi->ext.len - 1;
79 start_blkaddr = fi->ext.blk_addr;
80
81 if (pgofs >= start_fofs && pgofs <= end_fofs) {
82 unsigned int blkbits = inode->i_sb->s_blocksize_bits;
83 size_t count;
84
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);
91 else
92 bh_result->b_size = UINT_MAX;
93
94 sbi->read_hit_ext++;
95 read_unlock(&fi->ext.ext_lock);
96 return 1;
97 }
98 read_unlock(&fi->ext.ext_lock);
99 return 0;
100}
101
102void update_extent_cache(block_t blk_addr, struct dnode_of_data *dn)
103{
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;
107
108 BUG_ON(blk_addr == NEW_ADDR);
109 fofs = start_bidx_of_node(ofs_of_node(dn->node_page)) + dn->ofs_in_node;
110
111 /* Update the page address in the parent node */
112 __set_data_blkaddr(dn, blk_addr);
113
114 write_lock(&fi->ext.ext_lock);
115
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;
120
121 /* Drop and initialize the matched extent */
122 if (fi->ext.len == 1 && fofs == start_fofs)
123 fi->ext.len = 0;
124
125 /* Initial extent */
126 if (fi->ext.len == 0) {
127 if (blk_addr != NULL_ADDR) {
128 fi->ext.fofs = fofs;
129 fi->ext.blk_addr = blk_addr;
130 fi->ext.len = 1;
131 }
132 goto end_update;
133 }
134
135 /* Frone merge */
136 if (fofs == start_fofs - 1 && blk_addr == start_blkaddr - 1) {
137 fi->ext.fofs--;
138 fi->ext.blk_addr--;
139 fi->ext.len++;
140 goto end_update;
141 }
142
143 /* Back merge */
144 if (fofs == end_fofs + 1 && blk_addr == end_blkaddr + 1) {
145 fi->ext.len++;
146 goto end_update;
147 }
148
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;
154 } else {
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;
159 }
160 goto end_update;
161 }
162 write_unlock(&fi->ext.ext_lock);
163 return;
164
165end_update:
166 write_unlock(&fi->ext.ext_lock);
167 sync_inode_page(dn);
168 return;
169}
170
171struct page *find_data_page(struct inode *inode, pgoff_t index)
172{
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;
176 struct page *page;
177 int err;
178
179 page = find_get_page(mapping, index);
180 if (page && PageUptodate(page))
181 return page;
182 f2fs_put_page(page, 0);
183
184 set_new_dnode(&dn, inode, NULL, NULL, 0);
185 err = get_dnode_of_data(&dn, index, RDONLY_NODE);
186 if (err)
187 return ERR_PTR(err);
188 f2fs_put_dnode(&dn);
189
190 if (dn.data_blkaddr == NULL_ADDR)
191 return ERR_PTR(-ENOENT);
192
193 /* By fallocate(), there is no cached page, but with NEW_ADDR */
194 if (dn.data_blkaddr == NEW_ADDR)
195 return ERR_PTR(-EINVAL);
196
197 page = grab_cache_page(mapping, index);
198 if (!page)
199 return ERR_PTR(-ENOMEM);
200
201 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
202 if (err) {
203 f2fs_put_page(page, 1);
204 return ERR_PTR(err);
205 }
206 unlock_page(page);
207 return page;
208}
209
210/**
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.
214 */
215struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
216{
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;
220 struct page *page;
221 int err;
222
223 set_new_dnode(&dn, inode, NULL, NULL, 0);
224 err = get_dnode_of_data(&dn, index, RDONLY_NODE);
225 if (err)
226 return ERR_PTR(err);
227 f2fs_put_dnode(&dn);
228
229 if (dn.data_blkaddr == NULL_ADDR)
230 return ERR_PTR(-ENOENT);
231
232 page = grab_cache_page(mapping, index);
233 if (!page)
234 return ERR_PTR(-ENOMEM);
235
236 if (PageUptodate(page))
237 return page;
238
239 BUG_ON(dn.data_blkaddr == NEW_ADDR);
240 BUG_ON(dn.data_blkaddr == NULL_ADDR);
241
242 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
243 if (err) {
244 f2fs_put_page(page, 1);
245 return ERR_PTR(err);
246 }
247 return page;
248}
249
250/**
251 * Caller ensures that this data page is never allocated.
252 * A new zero-filled data page is allocated in the page cache.
253 */
254struct page *get_new_data_page(struct inode *inode, pgoff_t index,
255 bool new_i_size)
256{
257 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
258 struct address_space *mapping = inode->i_mapping;
259 struct page *page;
260 struct dnode_of_data dn;
261 int err;
262
263 set_new_dnode(&dn, inode, NULL, NULL, 0);
264 err = get_dnode_of_data(&dn, index, 0);
265 if (err)
266 return ERR_PTR(err);
267
268 if (dn.data_blkaddr == NULL_ADDR) {
269 if (reserve_new_block(&dn)) {
270 f2fs_put_dnode(&dn);
271 return ERR_PTR(-ENOSPC);
272 }
273 }
274 f2fs_put_dnode(&dn);
275
276 page = grab_cache_page(mapping, index);
277 if (!page)
278 return ERR_PTR(-ENOMEM);
279
280 if (PageUptodate(page))
281 return page;
282
283 if (dn.data_blkaddr == NEW_ADDR) {
284 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
285 } else {
286 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
287 if (err) {
288 f2fs_put_page(page, 1);
289 return ERR_PTR(err);
290 }
291 }
292 SetPageUptodate(page);
293
294 if (new_i_size &&
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);
298 }
299 return page;
300}
301
302static void read_end_io(struct bio *bio, int err)
303{
304 const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
305 struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
306
307 do {
308 struct page *page = bvec->bv_page;
309
310 if (--bvec >= bio->bi_io_vec)
311 prefetchw(&bvec->bv_page->flags);
312
313 if (uptodate) {
314 SetPageUptodate(page);
315 } else {
316 ClearPageUptodate(page);
317 SetPageError(page);
318 }
319 unlock_page(page);
320 } while (bvec >= bio->bi_io_vec);
321 kfree(bio->bi_private);
322 bio_put(bio);
323}
324
325/**
326 * Fill the locked page with data located in the block address.
327 * Read operation is synchronous, and caller must unlock the page.
328 */
329int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
330 block_t blk_addr, int type)
331{
332 struct block_device *bdev = sbi->sb->s_bdev;
333 bool sync = (type == READ_SYNC);
334 struct bio *bio;
335
336 /* This page can be already read by other threads */
337 if (PageUptodate(page)) {
338 if (!sync)
339 unlock_page(page);
340 return 0;
341 }
342
343 down_read(&sbi->bio_sem);
344
345 /* Allocate a new bio */
346 bio = f2fs_bio_alloc(bdev, blk_addr << (sbi->log_blocksize - 9),
347 1, GFP_NOFS | __GFP_HIGH);
348
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);
353 bio_put(bio);
354 up_read(&sbi->bio_sem);
355 return -EFAULT;
356 }
357
358 submit_bio(type, bio);
359 up_read(&sbi->bio_sem);
360
361 /* wait for read completion if sync */
362 if (sync) {
363 lock_page(page);
364 if (PageError(page))
365 return -EIO;
366 }
367 return 0;
368}
369
370/**
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
374 * mechanism.
375 */
376static int get_data_block_ro(struct inode *inode, sector_t iblock,
377 struct buffer_head *bh_result, int create)
378{
379 unsigned int blkbits = inode->i_sb->s_blocksize_bits;
380 unsigned maxblocks = bh_result->b_size >> blkbits;
381 struct dnode_of_data dn;
382 pgoff_t pgofs;
383 int err;
384
385 /* Get the page offset from the block offset(iblock) */
386 pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
387
388 if (check_extent_cache(inode, pgofs, bh_result))
389 return 0;
390
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);
394 if (err)
395 return (err == -ENOENT) ? 0 : err;
396
397 /* It does not support data allocation */
398 BUG_ON(create);
399
400 if (dn.data_blkaddr != NEW_ADDR && dn.data_blkaddr != NULL_ADDR) {
401 int i;
402 unsigned int end_offset;
403
404 end_offset = IS_INODE(dn.node_page) ?
405 ADDRS_PER_INODE :
406 ADDRS_PER_BLOCK;
407
408 clear_buffer_new(bh_result);
409
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,
413 dn.ofs_in_node + i))
414 != (dn.data_blkaddr + i)) || maxblocks == i)
415 break;
416 map_bh(bh_result, inode->i_sb, dn.data_blkaddr);
417 bh_result->b_size = (i << blkbits);
418 }
419 f2fs_put_dnode(&dn);
420 return 0;
421}
422
423static int f2fs_read_data_page(struct file *file, struct page *page)
424{
425 return mpage_readpage(page, get_data_block_ro);
426}
427
428static int f2fs_read_data_pages(struct file *file,
429 struct address_space *mapping,
430 struct list_head *pages, unsigned nr_pages)
431{
432 return mpage_readpages(mapping, pages, nr_pages, get_data_block_ro);
433}
434
435int do_write_data_page(struct page *page)
436{
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;
441 int err = 0;
442
443 set_new_dnode(&dn, inode, NULL, NULL, 0);
444 err = get_dnode_of_data(&dn, page->index, RDONLY_NODE);
445 if (err)
446 return err;
447
448 old_blk_addr = dn.data_blkaddr;
449
450 /* This page is already truncated */
451 if (old_blk_addr == NULL_ADDR)
452 goto out_writepage;
453
454 set_page_writeback(page);
455
456 /*
457 * If current allocation needs SSR,
458 * it had better in-place writes for updated data.
459 */
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,
463 old_blk_addr);
464 } else {
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);
470 }
471out_writepage:
472 f2fs_put_dnode(&dn);
473 return err;
474}
475
476static int f2fs_write_data_page(struct page *page,
477 struct writeback_control *wbc)
478{
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)
483 >> PAGE_CACHE_SHIFT;
484 unsigned offset;
485 int err = 0;
486
487 if (page->index < end_index)
488 goto out;
489
490 /*
491 * If the offset is out-of-range of file size,
492 * this page does not have to be written to disk.
493 */
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);
499 }
500 goto unlock_out;
501 }
502
503 zero_user_segment(page, offset, PAGE_CACHE_SIZE);
504out:
505 if (sbi->por_doing)
506 goto redirty_out;
507
508 if (wbc->for_reclaim && !S_ISDIR(inode->i_mode) && !is_cold_data(page))
509 goto redirty_out;
510
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);
515 }
516 err = do_write_data_page(page);
517 if (err && err != -ENOENT) {
518 wbc->pages_skipped++;
519 set_page_dirty(page);
520 }
521 mutex_unlock_op(sbi, DATA_WRITE);
522
523 if (wbc->for_reclaim)
524 f2fs_submit_bio(sbi, DATA, true);
525
526 if (err == -ENOENT)
527 goto unlock_out;
528
529 clear_cold_data(page);
530 unlock_page(page);
531
532 if (!wbc->for_reclaim && !S_ISDIR(inode->i_mode))
533 f2fs_balance_fs(sbi);
534 return 0;
535
536unlock_out:
537 unlock_page(page);
538 return (err == -ENOENT) ? 0 : err;
539
540redirty_out:
541 wbc->pages_skipped++;
542 set_page_dirty(page);
543 return AOP_WRITEPAGE_ACTIVATE;
544}
545
546#define MAX_DESIRED_PAGES_WP 4096
547
25ca923b 548static int f2fs_write_data_pages(struct address_space *mapping,
eb47b800
JK		 549 struct writeback_control *wbc)
550{
551 struct inode *inode = mapping->host;
552 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
553 int ret;
554 long excess_nrtw = 0, desired_nrtw;
555
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;
560 }
561
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));
568
569 remove_dirty_dir_inode(inode);
570
571 wbc->nr_to_write -= excess_nrtw;
572 return ret;
573}
574
575static 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)
578{
579 struct inode *inode = mapping->host;
580 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
581 struct page *page;
582 pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
583 struct dnode_of_data dn;
584 int err = 0;
585
586 /* for nobh_write_end */
587 *fsdata = NULL;
588
589 f2fs_balance_fs(sbi);
590
591 page = grab_cache_page_write_begin(mapping, index, flags);
592 if (!page)
593 return -ENOMEM;
594 *pagep = page;
595
596 mutex_lock_op(sbi, DATA_NEW);
597
598 set_new_dnode(&dn, inode, NULL, NULL, 0);
599 err = get_dnode_of_data(&dn, index, 0);
600 if (err) {
601 mutex_unlock_op(sbi, DATA_NEW);
602 f2fs_put_page(page, 1);
603 return err;
604 }
605
606 if (dn.data_blkaddr == NULL_ADDR) {
607 err = reserve_new_block(&dn);
608 if (err) {
609 f2fs_put_dnode(&dn);
610 mutex_unlock_op(sbi, DATA_NEW);
611 f2fs_put_page(page, 1);
612 return err;
613 }
614 }
615 f2fs_put_dnode(&dn);
616
617 mutex_unlock_op(sbi, DATA_NEW);
618
619 if ((len == PAGE_CACHE_SIZE) || PageUptodate(page))
620 return 0;
621
622 if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
623 unsigned start = pos & (PAGE_CACHE_SIZE - 1);
624 unsigned end = start + len;
625
626 /* Reading beyond i_size is simple: memset to zero */
627 zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
628 return 0;
629 }
630
631 if (dn.data_blkaddr == NEW_ADDR) {
632 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
633 } else {
634 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
635 if (err) {
636 f2fs_put_page(page, 1);
637 return err;
638 }
639 }
640 SetPageUptodate(page);
641 clear_cold_data(page);
642 return 0;
643}
644
645static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
646 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
647{
648 struct file *file = iocb->ki_filp;
649 struct inode *inode = file->f_mapping->host;
650
651 if (rw == WRITE)
652 return 0;
653
654 /* Needs synchronization with the cleaner */
655 return blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
656 get_data_block_ro);
657}
658
659static void f2fs_invalidate_data_page(struct page *page, unsigned long offset)
660{
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);
666 }
667 ClearPagePrivate(page);
668}
669
670static int f2fs_release_data_page(struct page *page, gfp_t wait)
671{
672 ClearPagePrivate(page);
673 return 0;
674}
675
676static int f2fs_set_data_page_dirty(struct page *page)
677{
678 struct address_space *mapping = page->mapping;
679 struct inode *inode = mapping->host;
680
681 SetPageUptodate(page);
682 if (!PageDirty(page)) {
683 __set_page_dirty_nobuffers(page);
684 set_dirty_dir_page(inode, page);
685 return 1;
686 }
687 return 0;
688}
689
690const 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,
701};