Merge tag 'f2fs-for-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeu...
[muen/linux.git] / fs / f2fs / data.c
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/pagevec.h>
18 #include <linux/blkdev.h>
19 #include <linux/bio.h>
20 #include <linux/prefetch.h>
21 #include <linux/uio.h>
22 #include <linux/mm.h>
23 #include <linux/memcontrol.h>
24 #include <linux/cleancache.h>
25 #include <linux/sched/signal.h>
26
27 #include "f2fs.h"
28 #include "node.h"
29 #include "segment.h"
30 #include "trace.h"
31 #include <trace/events/f2fs.h>
32
33 static bool __is_cp_guaranteed(struct page *page)
34 {
35         struct address_space *mapping = page->mapping;
36         struct inode *inode;
37         struct f2fs_sb_info *sbi;
38
39         if (!mapping)
40                 return false;
41
42         inode = mapping->host;
43         sbi = F2FS_I_SB(inode);
44
45         if (inode->i_ino == F2FS_META_INO(sbi) ||
46                         inode->i_ino ==  F2FS_NODE_INO(sbi) ||
47                         S_ISDIR(inode->i_mode) ||
48                         is_cold_data(page))
49                 return true;
50         return false;
51 }
52
53 static void f2fs_read_end_io(struct bio *bio)
54 {
55         struct bio_vec *bvec;
56         int i;
57
58 #ifdef CONFIG_F2FS_FAULT_INJECTION
59         if (time_to_inject(F2FS_P_SB(bio_first_page_all(bio)), FAULT_IO)) {
60                 f2fs_show_injection_info(FAULT_IO);
61                 bio->bi_status = BLK_STS_IOERR;
62         }
63 #endif
64
65         if (f2fs_bio_encrypted(bio)) {
66                 if (bio->bi_status) {
67                         fscrypt_release_ctx(bio->bi_private);
68                 } else {
69                         fscrypt_decrypt_bio_pages(bio->bi_private, bio);
70                         return;
71                 }
72         }
73
74         bio_for_each_segment_all(bvec, bio, i) {
75                 struct page *page = bvec->bv_page;
76
77                 if (!bio->bi_status) {
78                         if (!PageUptodate(page))
79                                 SetPageUptodate(page);
80                 } else {
81                         ClearPageUptodate(page);
82                         SetPageError(page);
83                 }
84                 unlock_page(page);
85         }
86         bio_put(bio);
87 }
88
89 static void f2fs_write_end_io(struct bio *bio)
90 {
91         struct f2fs_sb_info *sbi = bio->bi_private;
92         struct bio_vec *bvec;
93         int i;
94
95         bio_for_each_segment_all(bvec, bio, i) {
96                 struct page *page = bvec->bv_page;
97                 enum count_type type = WB_DATA_TYPE(page);
98
99                 if (IS_DUMMY_WRITTEN_PAGE(page)) {
100                         set_page_private(page, (unsigned long)NULL);
101                         ClearPagePrivate(page);
102                         unlock_page(page);
103                         mempool_free(page, sbi->write_io_dummy);
104
105                         if (unlikely(bio->bi_status))
106                                 f2fs_stop_checkpoint(sbi, true);
107                         continue;
108                 }
109
110                 fscrypt_pullback_bio_page(&page, true);
111
112                 if (unlikely(bio->bi_status)) {
113                         mapping_set_error(page->mapping, -EIO);
114                         if (type == F2FS_WB_CP_DATA)
115                                 f2fs_stop_checkpoint(sbi, true);
116                 }
117
118                 f2fs_bug_on(sbi, page->mapping == NODE_MAPPING(sbi) &&
119                                         page->index != nid_of_node(page));
120
121                 dec_page_count(sbi, type);
122                 clear_cold_data(page);
123                 end_page_writeback(page);
124         }
125         if (!get_pages(sbi, F2FS_WB_CP_DATA) &&
126                                 wq_has_sleeper(&sbi->cp_wait))
127                 wake_up(&sbi->cp_wait);
128
129         bio_put(bio);
130 }
131
132 /*
133  * Return true, if pre_bio's bdev is same as its target device.
134  */
135 struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
136                                 block_t blk_addr, struct bio *bio)
137 {
138         struct block_device *bdev = sbi->sb->s_bdev;
139         int i;
140
141         for (i = 0; i < sbi->s_ndevs; i++) {
142                 if (FDEV(i).start_blk <= blk_addr &&
143                                         FDEV(i).end_blk >= blk_addr) {
144                         blk_addr -= FDEV(i).start_blk;
145                         bdev = FDEV(i).bdev;
146                         break;
147                 }
148         }
149         if (bio) {
150                 bio_set_dev(bio, bdev);
151                 bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
152         }
153         return bdev;
154 }
155
156 int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr)
157 {
158         int i;
159
160         for (i = 0; i < sbi->s_ndevs; i++)
161                 if (FDEV(i).start_blk <= blkaddr && FDEV(i).end_blk >= blkaddr)
162                         return i;
163         return 0;
164 }
165
166 static bool __same_bdev(struct f2fs_sb_info *sbi,
167                                 block_t blk_addr, struct bio *bio)
168 {
169         struct block_device *b = f2fs_target_device(sbi, blk_addr, NULL);
170         return bio->bi_disk == b->bd_disk && bio->bi_partno == b->bd_partno;
171 }
172
173 /*
174  * Low-level block read/write IO operations.
175  */
176 static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
177                                 struct writeback_control *wbc,
178                                 int npages, bool is_read)
179 {
180         struct bio *bio;
181
182         bio = f2fs_bio_alloc(sbi, npages, true);
183
184         f2fs_target_device(sbi, blk_addr, bio);
185         bio->bi_end_io = is_read ? f2fs_read_end_io : f2fs_write_end_io;
186         bio->bi_private = is_read ? NULL : sbi;
187         if (wbc)
188                 wbc_init_bio(wbc, bio);
189
190         return bio;
191 }
192
193 static inline void __submit_bio(struct f2fs_sb_info *sbi,
194                                 struct bio *bio, enum page_type type)
195 {
196         if (!is_read_io(bio_op(bio))) {
197                 unsigned int start;
198
199                 if (f2fs_sb_mounted_blkzoned(sbi->sb) &&
200                         current->plug && (type == DATA || type == NODE))
201                         blk_finish_plug(current->plug);
202
203                 if (type != DATA && type != NODE)
204                         goto submit_io;
205
206                 start = bio->bi_iter.bi_size >> F2FS_BLKSIZE_BITS;
207                 start %= F2FS_IO_SIZE(sbi);
208
209                 if (start == 0)
210                         goto submit_io;
211
212                 /* fill dummy pages */
213                 for (; start < F2FS_IO_SIZE(sbi); start++) {
214                         struct page *page =
215                                 mempool_alloc(sbi->write_io_dummy,
216                                         GFP_NOIO | __GFP_ZERO | __GFP_NOFAIL);
217                         f2fs_bug_on(sbi, !page);
218
219                         SetPagePrivate(page);
220                         set_page_private(page, (unsigned long)DUMMY_WRITTEN_PAGE);
221                         lock_page(page);
222                         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE)
223                                 f2fs_bug_on(sbi, 1);
224                 }
225                 /*
226                  * In the NODE case, we lose next block address chain. So, we
227                  * need to do checkpoint in f2fs_sync_file.
228                  */
229                 if (type == NODE)
230                         set_sbi_flag(sbi, SBI_NEED_CP);
231         }
232 submit_io:
233         if (is_read_io(bio_op(bio)))
234                 trace_f2fs_submit_read_bio(sbi->sb, type, bio);
235         else
236                 trace_f2fs_submit_write_bio(sbi->sb, type, bio);
237         submit_bio(bio);
238 }
239
240 static void __submit_merged_bio(struct f2fs_bio_info *io)
241 {
242         struct f2fs_io_info *fio = &io->fio;
243
244         if (!io->bio)
245                 return;
246
247         bio_set_op_attrs(io->bio, fio->op, fio->op_flags);
248
249         if (is_read_io(fio->op))
250                 trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
251         else
252                 trace_f2fs_prepare_write_bio(io->sbi->sb, fio->type, io->bio);
253
254         __submit_bio(io->sbi, io->bio, fio->type);
255         io->bio = NULL;
256 }
257
258 static bool __has_merged_page(struct f2fs_bio_info *io,
259                                 struct inode *inode, nid_t ino, pgoff_t idx)
260 {
261         struct bio_vec *bvec;
262         struct page *target;
263         int i;
264
265         if (!io->bio)
266                 return false;
267
268         if (!inode && !ino)
269                 return true;
270
271         bio_for_each_segment_all(bvec, io->bio, i) {
272
273                 if (bvec->bv_page->mapping)
274                         target = bvec->bv_page;
275                 else
276                         target = fscrypt_control_page(bvec->bv_page);
277
278                 if (idx != target->index)
279                         continue;
280
281                 if (inode && inode == target->mapping->host)
282                         return true;
283                 if (ino && ino == ino_of_node(target))
284                         return true;
285         }
286
287         return false;
288 }
289
290 static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
291                                 nid_t ino, pgoff_t idx, enum page_type type)
292 {
293         enum page_type btype = PAGE_TYPE_OF_BIO(type);
294         enum temp_type temp;
295         struct f2fs_bio_info *io;
296         bool ret = false;
297
298         for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
299                 io = sbi->write_io[btype] + temp;
300
301                 down_read(&io->io_rwsem);
302                 ret = __has_merged_page(io, inode, ino, idx);
303                 up_read(&io->io_rwsem);
304
305                 /* TODO: use HOT temp only for meta pages now. */
306                 if (ret || btype == META)
307                         break;
308         }
309         return ret;
310 }
311
312 static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
313                                 enum page_type type, enum temp_type temp)
314 {
315         enum page_type btype = PAGE_TYPE_OF_BIO(type);
316         struct f2fs_bio_info *io = sbi->write_io[btype] + temp;
317
318         down_write(&io->io_rwsem);
319
320         /* change META to META_FLUSH in the checkpoint procedure */
321         if (type >= META_FLUSH) {
322                 io->fio.type = META_FLUSH;
323                 io->fio.op = REQ_OP_WRITE;
324                 io->fio.op_flags = REQ_META | REQ_PRIO | REQ_SYNC;
325                 if (!test_opt(sbi, NOBARRIER))
326                         io->fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
327         }
328         __submit_merged_bio(io);
329         up_write(&io->io_rwsem);
330 }
331
332 static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
333                                 struct inode *inode, nid_t ino, pgoff_t idx,
334                                 enum page_type type, bool force)
335 {
336         enum temp_type temp;
337
338         if (!force && !has_merged_page(sbi, inode, ino, idx, type))
339                 return;
340
341         for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
342
343                 __f2fs_submit_merged_write(sbi, type, temp);
344
345                 /* TODO: use HOT temp only for meta pages now. */
346                 if (type >= META)
347                         break;
348         }
349 }
350
351 void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
352 {
353         __submit_merged_write_cond(sbi, NULL, 0, 0, type, true);
354 }
355
356 void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
357                                 struct inode *inode, nid_t ino, pgoff_t idx,
358                                 enum page_type type)
359 {
360         __submit_merged_write_cond(sbi, inode, ino, idx, type, false);
361 }
362
363 void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
364 {
365         f2fs_submit_merged_write(sbi, DATA);
366         f2fs_submit_merged_write(sbi, NODE);
367         f2fs_submit_merged_write(sbi, META);
368 }
369
370 /*
371  * Fill the locked page with data located in the block address.
372  * A caller needs to unlock the page on failure.
373  */
374 int f2fs_submit_page_bio(struct f2fs_io_info *fio)
375 {
376         struct bio *bio;
377         struct page *page = fio->encrypted_page ?
378                         fio->encrypted_page : fio->page;
379
380         trace_f2fs_submit_page_bio(page, fio);
381         f2fs_trace_ios(fio, 0);
382
383         /* Allocate a new bio */
384         bio = __bio_alloc(fio->sbi, fio->new_blkaddr, fio->io_wbc,
385                                 1, is_read_io(fio->op));
386
387         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
388                 bio_put(bio);
389                 return -EFAULT;
390         }
391         bio_set_op_attrs(bio, fio->op, fio->op_flags);
392
393         __submit_bio(fio->sbi, bio, fio->type);
394
395         if (!is_read_io(fio->op))
396                 inc_page_count(fio->sbi, WB_DATA_TYPE(fio->page));
397         return 0;
398 }
399
400 int f2fs_submit_page_write(struct f2fs_io_info *fio)
401 {
402         struct f2fs_sb_info *sbi = fio->sbi;
403         enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
404         struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
405         struct page *bio_page;
406         int err = 0;
407
408         f2fs_bug_on(sbi, is_read_io(fio->op));
409
410         down_write(&io->io_rwsem);
411 next:
412         if (fio->in_list) {
413                 spin_lock(&io->io_lock);
414                 if (list_empty(&io->io_list)) {
415                         spin_unlock(&io->io_lock);
416                         goto out_fail;
417                 }
418                 fio = list_first_entry(&io->io_list,
419                                                 struct f2fs_io_info, list);
420                 list_del(&fio->list);
421                 spin_unlock(&io->io_lock);
422         }
423
424         if (fio->old_blkaddr != NEW_ADDR)
425                 verify_block_addr(sbi, fio->old_blkaddr);
426         verify_block_addr(sbi, fio->new_blkaddr);
427
428         bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
429
430         /* set submitted = true as a return value */
431         fio->submitted = true;
432
433         inc_page_count(sbi, WB_DATA_TYPE(bio_page));
434
435         if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
436             (io->fio.op != fio->op || io->fio.op_flags != fio->op_flags) ||
437                         !__same_bdev(sbi, fio->new_blkaddr, io->bio)))
438                 __submit_merged_bio(io);
439 alloc_new:
440         if (io->bio == NULL) {
441                 if ((fio->type == DATA || fio->type == NODE) &&
442                                 fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
443                         err = -EAGAIN;
444                         dec_page_count(sbi, WB_DATA_TYPE(bio_page));
445                         goto out_fail;
446                 }
447                 io->bio = __bio_alloc(sbi, fio->new_blkaddr, fio->io_wbc,
448                                                 BIO_MAX_PAGES, false);
449                 io->fio = *fio;
450         }
451
452         if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) < PAGE_SIZE) {
453                 __submit_merged_bio(io);
454                 goto alloc_new;
455         }
456
457         if (fio->io_wbc)
458                 wbc_account_io(fio->io_wbc, bio_page, PAGE_SIZE);
459
460         io->last_block_in_bio = fio->new_blkaddr;
461         f2fs_trace_ios(fio, 0);
462
463         trace_f2fs_submit_page_write(fio->page, fio);
464
465         if (fio->in_list)
466                 goto next;
467 out_fail:
468         up_write(&io->io_rwsem);
469         return err;
470 }
471
472 static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
473                                                          unsigned nr_pages)
474 {
475         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
476         struct fscrypt_ctx *ctx = NULL;
477         struct bio *bio;
478
479         if (f2fs_encrypted_file(inode)) {
480                 ctx = fscrypt_get_ctx(inode, GFP_NOFS);
481                 if (IS_ERR(ctx))
482                         return ERR_CAST(ctx);
483
484                 /* wait the page to be moved by cleaning */
485                 f2fs_wait_on_block_writeback(sbi, blkaddr);
486         }
487
488         bio = f2fs_bio_alloc(sbi, min_t(int, nr_pages, BIO_MAX_PAGES), false);
489         if (!bio) {
490                 if (ctx)
491                         fscrypt_release_ctx(ctx);
492                 return ERR_PTR(-ENOMEM);
493         }
494         f2fs_target_device(sbi, blkaddr, bio);
495         bio->bi_end_io = f2fs_read_end_io;
496         bio->bi_private = ctx;
497         bio_set_op_attrs(bio, REQ_OP_READ, 0);
498
499         return bio;
500 }
501
502 /* This can handle encryption stuffs */
503 static int f2fs_submit_page_read(struct inode *inode, struct page *page,
504                                                         block_t blkaddr)
505 {
506         struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1);
507
508         if (IS_ERR(bio))
509                 return PTR_ERR(bio);
510
511         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
512                 bio_put(bio);
513                 return -EFAULT;
514         }
515         __submit_bio(F2FS_I_SB(inode), bio, DATA);
516         return 0;
517 }
518
519 static void __set_data_blkaddr(struct dnode_of_data *dn)
520 {
521         struct f2fs_node *rn = F2FS_NODE(dn->node_page);
522         __le32 *addr_array;
523         int base = 0;
524
525         if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))
526                 base = get_extra_isize(dn->inode);
527
528         /* Get physical address of data block */
529         addr_array = blkaddr_in_node(rn);
530         addr_array[base + dn->ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
531 }
532
533 /*
534  * Lock ordering for the change of data block address:
535  * ->data_page
536  *  ->node_page
537  *    update block addresses in the node page
538  */
539 void set_data_blkaddr(struct dnode_of_data *dn)
540 {
541         f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
542         __set_data_blkaddr(dn);
543         if (set_page_dirty(dn->node_page))
544                 dn->node_changed = true;
545 }
546
547 void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
548 {
549         dn->data_blkaddr = blkaddr;
550         set_data_blkaddr(dn);
551         f2fs_update_extent_cache(dn);
552 }
553
554 /* dn->ofs_in_node will be returned with up-to-date last block pointer */
555 int reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)
556 {
557         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
558         int err;
559
560         if (!count)
561                 return 0;
562
563         if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
564                 return -EPERM;
565         if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
566                 return err;
567
568         trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
569                                                 dn->ofs_in_node, count);
570
571         f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
572
573         for (; count > 0; dn->ofs_in_node++) {
574                 block_t blkaddr = datablock_addr(dn->inode,
575                                         dn->node_page, dn->ofs_in_node);
576                 if (blkaddr == NULL_ADDR) {
577                         dn->data_blkaddr = NEW_ADDR;
578                         __set_data_blkaddr(dn);
579                         count--;
580                 }
581         }
582
583         if (set_page_dirty(dn->node_page))
584                 dn->node_changed = true;
585         return 0;
586 }
587
588 /* Should keep dn->ofs_in_node unchanged */
589 int reserve_new_block(struct dnode_of_data *dn)
590 {
591         unsigned int ofs_in_node = dn->ofs_in_node;
592         int ret;
593
594         ret = reserve_new_blocks(dn, 1);
595         dn->ofs_in_node = ofs_in_node;
596         return ret;
597 }
598
599 int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
600 {
601         bool need_put = dn->inode_page ? false : true;
602         int err;
603
604         err = get_dnode_of_data(dn, index, ALLOC_NODE);
605         if (err)
606                 return err;
607
608         if (dn->data_blkaddr == NULL_ADDR)
609                 err = reserve_new_block(dn);
610         if (err || need_put)
611                 f2fs_put_dnode(dn);
612         return err;
613 }
614
615 int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
616 {
617         struct extent_info ei  = {0,0,0};
618         struct inode *inode = dn->inode;
619
620         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
621                 dn->data_blkaddr = ei.blk + index - ei.fofs;
622                 return 0;
623         }
624
625         return f2fs_reserve_block(dn, index);
626 }
627
628 struct page *get_read_data_page(struct inode *inode, pgoff_t index,
629                                                 int op_flags, bool for_write)
630 {
631         struct address_space *mapping = inode->i_mapping;
632         struct dnode_of_data dn;
633         struct page *page;
634         struct extent_info ei = {0,0,0};
635         int err;
636
637         page = f2fs_grab_cache_page(mapping, index, for_write);
638         if (!page)
639                 return ERR_PTR(-ENOMEM);
640
641         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
642                 dn.data_blkaddr = ei.blk + index - ei.fofs;
643                 goto got_it;
644         }
645
646         set_new_dnode(&dn, inode, NULL, NULL, 0);
647         err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
648         if (err)
649                 goto put_err;
650         f2fs_put_dnode(&dn);
651
652         if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
653                 err = -ENOENT;
654                 goto put_err;
655         }
656 got_it:
657         if (PageUptodate(page)) {
658                 unlock_page(page);
659                 return page;
660         }
661
662         /*
663          * A new dentry page is allocated but not able to be written, since its
664          * new inode page couldn't be allocated due to -ENOSPC.
665          * In such the case, its blkaddr can be remained as NEW_ADDR.
666          * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
667          */
668         if (dn.data_blkaddr == NEW_ADDR) {
669                 zero_user_segment(page, 0, PAGE_SIZE);
670                 if (!PageUptodate(page))
671                         SetPageUptodate(page);
672                 unlock_page(page);
673                 return page;
674         }
675
676         err = f2fs_submit_page_read(inode, page, dn.data_blkaddr);
677         if (err)
678                 goto put_err;
679         return page;
680
681 put_err:
682         f2fs_put_page(page, 1);
683         return ERR_PTR(err);
684 }
685
686 struct page *find_data_page(struct inode *inode, pgoff_t index)
687 {
688         struct address_space *mapping = inode->i_mapping;
689         struct page *page;
690
691         page = find_get_page(mapping, index);
692         if (page && PageUptodate(page))
693                 return page;
694         f2fs_put_page(page, 0);
695
696         page = get_read_data_page(inode, index, 0, false);
697         if (IS_ERR(page))
698                 return page;
699
700         if (PageUptodate(page))
701                 return page;
702
703         wait_on_page_locked(page);
704         if (unlikely(!PageUptodate(page))) {
705                 f2fs_put_page(page, 0);
706                 return ERR_PTR(-EIO);
707         }
708         return page;
709 }
710
711 /*
712  * If it tries to access a hole, return an error.
713  * Because, the callers, functions in dir.c and GC, should be able to know
714  * whether this page exists or not.
715  */
716 struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
717                                                         bool for_write)
718 {
719         struct address_space *mapping = inode->i_mapping;
720         struct page *page;
721 repeat:
722         page = get_read_data_page(inode, index, 0, for_write);
723         if (IS_ERR(page))
724                 return page;
725
726         /* wait for read completion */
727         lock_page(page);
728         if (unlikely(page->mapping != mapping)) {
729                 f2fs_put_page(page, 1);
730                 goto repeat;
731         }
732         if (unlikely(!PageUptodate(page))) {
733                 f2fs_put_page(page, 1);
734                 return ERR_PTR(-EIO);
735         }
736         return page;
737 }
738
739 /*
740  * Caller ensures that this data page is never allocated.
741  * A new zero-filled data page is allocated in the page cache.
742  *
743  * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
744  * f2fs_unlock_op().
745  * Note that, ipage is set only by make_empty_dir, and if any error occur,
746  * ipage should be released by this function.
747  */
748 struct page *get_new_data_page(struct inode *inode,
749                 struct page *ipage, pgoff_t index, bool new_i_size)
750 {
751         struct address_space *mapping = inode->i_mapping;
752         struct page *page;
753         struct dnode_of_data dn;
754         int err;
755
756         page = f2fs_grab_cache_page(mapping, index, true);
757         if (!page) {
758                 /*
759                  * before exiting, we should make sure ipage will be released
760                  * if any error occur.
761                  */
762                 f2fs_put_page(ipage, 1);
763                 return ERR_PTR(-ENOMEM);
764         }
765
766         set_new_dnode(&dn, inode, ipage, NULL, 0);
767         err = f2fs_reserve_block(&dn, index);
768         if (err) {
769                 f2fs_put_page(page, 1);
770                 return ERR_PTR(err);
771         }
772         if (!ipage)
773                 f2fs_put_dnode(&dn);
774
775         if (PageUptodate(page))
776                 goto got_it;
777
778         if (dn.data_blkaddr == NEW_ADDR) {
779                 zero_user_segment(page, 0, PAGE_SIZE);
780                 if (!PageUptodate(page))
781                         SetPageUptodate(page);
782         } else {
783                 f2fs_put_page(page, 1);
784
785                 /* if ipage exists, blkaddr should be NEW_ADDR */
786                 f2fs_bug_on(F2FS_I_SB(inode), ipage);
787                 page = get_lock_data_page(inode, index, true);
788                 if (IS_ERR(page))
789                         return page;
790         }
791 got_it:
792         if (new_i_size && i_size_read(inode) <
793                                 ((loff_t)(index + 1) << PAGE_SHIFT))
794                 f2fs_i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
795         return page;
796 }
797
798 static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
799 {
800         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
801         struct f2fs_summary sum;
802         struct node_info ni;
803         pgoff_t fofs;
804         blkcnt_t count = 1;
805         int err;
806
807         if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
808                 return -EPERM;
809
810         dn->data_blkaddr = datablock_addr(dn->inode,
811                                 dn->node_page, dn->ofs_in_node);
812         if (dn->data_blkaddr == NEW_ADDR)
813                 goto alloc;
814
815         if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
816                 return err;
817
818 alloc:
819         get_node_info(sbi, dn->nid, &ni);
820         set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
821
822         allocate_data_block(sbi, NULL, dn->data_blkaddr, &dn->data_blkaddr,
823                                         &sum, seg_type, NULL, false);
824         set_data_blkaddr(dn);
825
826         /* update i_size */
827         fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
828                                                         dn->ofs_in_node;
829         if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_SHIFT))
830                 f2fs_i_size_write(dn->inode,
831                                 ((loff_t)(fofs + 1) << PAGE_SHIFT));
832         return 0;
833 }
834
835 static inline bool __force_buffered_io(struct inode *inode, int rw)
836 {
837         return (f2fs_encrypted_file(inode) ||
838                         (rw == WRITE && test_opt(F2FS_I_SB(inode), LFS)) ||
839                         F2FS_I_SB(inode)->s_ndevs);
840 }
841
842 int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
843 {
844         struct inode *inode = file_inode(iocb->ki_filp);
845         struct f2fs_map_blocks map;
846         int flag;
847         int err = 0;
848         bool direct_io = iocb->ki_flags & IOCB_DIRECT;
849
850         /* convert inline data for Direct I/O*/
851         if (direct_io) {
852                 err = f2fs_convert_inline_inode(inode);
853                 if (err)
854                         return err;
855         }
856
857         if (is_inode_flag_set(inode, FI_NO_PREALLOC))
858                 return 0;
859
860         map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
861         map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
862         if (map.m_len > map.m_lblk)
863                 map.m_len -= map.m_lblk;
864         else
865                 map.m_len = 0;
866
867         map.m_next_pgofs = NULL;
868         map.m_next_extent = NULL;
869         map.m_seg_type = NO_CHECK_TYPE;
870
871         if (direct_io) {
872                 map.m_seg_type = rw_hint_to_seg_type(iocb->ki_hint);
873                 flag = __force_buffered_io(inode, WRITE) ?
874                                         F2FS_GET_BLOCK_PRE_AIO :
875                                         F2FS_GET_BLOCK_PRE_DIO;
876                 goto map_blocks;
877         }
878         if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA(inode)) {
879                 err = f2fs_convert_inline_inode(inode);
880                 if (err)
881                         return err;
882         }
883         if (f2fs_has_inline_data(inode))
884                 return err;
885
886         flag = F2FS_GET_BLOCK_PRE_AIO;
887
888 map_blocks:
889         err = f2fs_map_blocks(inode, &map, 1, flag);
890         if (map.m_len > 0 && err == -ENOSPC) {
891                 if (!direct_io)
892                         set_inode_flag(inode, FI_NO_PREALLOC);
893                 err = 0;
894         }
895         return err;
896 }
897
898 static inline void __do_map_lock(struct f2fs_sb_info *sbi, int flag, bool lock)
899 {
900         if (flag == F2FS_GET_BLOCK_PRE_AIO) {
901                 if (lock)
902                         down_read(&sbi->node_change);
903                 else
904                         up_read(&sbi->node_change);
905         } else {
906                 if (lock)
907                         f2fs_lock_op(sbi);
908                 else
909                         f2fs_unlock_op(sbi);
910         }
911 }
912
913 /*
914  * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
915  * f2fs_map_blocks structure.
916  * If original data blocks are allocated, then give them to blockdev.
917  * Otherwise,
918  *     a. preallocate requested block addresses
919  *     b. do not use extent cache for better performance
920  *     c. give the block addresses to blockdev
921  */
922 int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
923                                                 int create, int flag)
924 {
925         unsigned int maxblocks = map->m_len;
926         struct dnode_of_data dn;
927         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
928         int mode = create ? ALLOC_NODE : LOOKUP_NODE;
929         pgoff_t pgofs, end_offset, end;
930         int err = 0, ofs = 1;
931         unsigned int ofs_in_node, last_ofs_in_node;
932         blkcnt_t prealloc;
933         struct extent_info ei = {0,0,0};
934         block_t blkaddr;
935         unsigned int start_pgofs;
936
937         if (!maxblocks)
938                 return 0;
939
940         map->m_len = 0;
941         map->m_flags = 0;
942
943         /* it only supports block size == page size */
944         pgofs = (pgoff_t)map->m_lblk;
945         end = pgofs + maxblocks;
946
947         if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
948                 map->m_pblk = ei.blk + pgofs - ei.fofs;
949                 map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
950                 map->m_flags = F2FS_MAP_MAPPED;
951                 if (map->m_next_extent)
952                         *map->m_next_extent = pgofs + map->m_len;
953                 goto out;
954         }
955
956 next_dnode:
957         if (create)
958                 __do_map_lock(sbi, flag, true);
959
960         /* When reading holes, we need its node page */
961         set_new_dnode(&dn, inode, NULL, NULL, 0);
962         err = get_dnode_of_data(&dn, pgofs, mode);
963         if (err) {
964                 if (flag == F2FS_GET_BLOCK_BMAP)
965                         map->m_pblk = 0;
966                 if (err == -ENOENT) {
967                         err = 0;
968                         if (map->m_next_pgofs)
969                                 *map->m_next_pgofs =
970                                         get_next_page_offset(&dn, pgofs);
971                         if (map->m_next_extent)
972                                 *map->m_next_extent =
973                                         get_next_page_offset(&dn, pgofs);
974                 }
975                 goto unlock_out;
976         }
977
978         start_pgofs = pgofs;
979         prealloc = 0;
980         last_ofs_in_node = ofs_in_node = dn.ofs_in_node;
981         end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
982
983 next_block:
984         blkaddr = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node);
985
986         if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
987                 if (create) {
988                         if (unlikely(f2fs_cp_error(sbi))) {
989                                 err = -EIO;
990                                 goto sync_out;
991                         }
992                         if (flag == F2FS_GET_BLOCK_PRE_AIO) {
993                                 if (blkaddr == NULL_ADDR) {
994                                         prealloc++;
995                                         last_ofs_in_node = dn.ofs_in_node;
996                                 }
997                         } else {
998                                 err = __allocate_data_block(&dn,
999                                                         map->m_seg_type);
1000                                 if (!err)
1001                                         set_inode_flag(inode, FI_APPEND_WRITE);
1002                         }
1003                         if (err)
1004                                 goto sync_out;
1005                         map->m_flags |= F2FS_MAP_NEW;
1006                         blkaddr = dn.data_blkaddr;
1007                 } else {
1008                         if (flag == F2FS_GET_BLOCK_BMAP) {
1009                                 map->m_pblk = 0;
1010                                 goto sync_out;
1011                         }
1012                         if (flag == F2FS_GET_BLOCK_PRECACHE)
1013                                 goto sync_out;
1014                         if (flag == F2FS_GET_BLOCK_FIEMAP &&
1015                                                 blkaddr == NULL_ADDR) {
1016                                 if (map->m_next_pgofs)
1017                                         *map->m_next_pgofs = pgofs + 1;
1018                                 goto sync_out;
1019                         }
1020                         if (flag != F2FS_GET_BLOCK_FIEMAP) {
1021                                 /* for defragment case */
1022                                 if (map->m_next_pgofs)
1023                                         *map->m_next_pgofs = pgofs + 1;
1024                                 goto sync_out;
1025                         }
1026                 }
1027         }
1028
1029         if (flag == F2FS_GET_BLOCK_PRE_AIO)
1030                 goto skip;
1031
1032         if (map->m_len == 0) {
1033                 /* preallocated unwritten block should be mapped for fiemap. */
1034                 if (blkaddr == NEW_ADDR)
1035                         map->m_flags |= F2FS_MAP_UNWRITTEN;
1036                 map->m_flags |= F2FS_MAP_MAPPED;
1037
1038                 map->m_pblk = blkaddr;
1039                 map->m_len = 1;
1040         } else if ((map->m_pblk != NEW_ADDR &&
1041                         blkaddr == (map->m_pblk + ofs)) ||
1042                         (map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
1043                         flag == F2FS_GET_BLOCK_PRE_DIO) {
1044                 ofs++;
1045                 map->m_len++;
1046         } else {
1047                 goto sync_out;
1048         }
1049
1050 skip:
1051         dn.ofs_in_node++;
1052         pgofs++;
1053
1054         /* preallocate blocks in batch for one dnode page */
1055         if (flag == F2FS_GET_BLOCK_PRE_AIO &&
1056                         (pgofs == end || dn.ofs_in_node == end_offset)) {
1057
1058                 dn.ofs_in_node = ofs_in_node;
1059                 err = reserve_new_blocks(&dn, prealloc);
1060                 if (err)
1061                         goto sync_out;
1062
1063                 map->m_len += dn.ofs_in_node - ofs_in_node;
1064                 if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
1065                         err = -ENOSPC;
1066                         goto sync_out;
1067                 }
1068                 dn.ofs_in_node = end_offset;
1069         }
1070
1071         if (pgofs >= end)
1072                 goto sync_out;
1073         else if (dn.ofs_in_node < end_offset)
1074                 goto next_block;
1075
1076         if (flag == F2FS_GET_BLOCK_PRECACHE) {
1077                 if (map->m_flags & F2FS_MAP_MAPPED) {
1078                         unsigned int ofs = start_pgofs - map->m_lblk;
1079
1080                         f2fs_update_extent_cache_range(&dn,
1081                                 start_pgofs, map->m_pblk + ofs,
1082                                 map->m_len - ofs);
1083                 }
1084         }
1085
1086         f2fs_put_dnode(&dn);
1087
1088         if (create) {
1089                 __do_map_lock(sbi, flag, false);
1090                 f2fs_balance_fs(sbi, dn.node_changed);
1091         }
1092         goto next_dnode;
1093
1094 sync_out:
1095         if (flag == F2FS_GET_BLOCK_PRECACHE) {
1096                 if (map->m_flags & F2FS_MAP_MAPPED) {
1097                         unsigned int ofs = start_pgofs - map->m_lblk;
1098
1099                         f2fs_update_extent_cache_range(&dn,
1100                                 start_pgofs, map->m_pblk + ofs,
1101                                 map->m_len - ofs);
1102                 }
1103                 if (map->m_next_extent)
1104                         *map->m_next_extent = pgofs + 1;
1105         }
1106         f2fs_put_dnode(&dn);
1107 unlock_out:
1108         if (create) {
1109                 __do_map_lock(sbi, flag, false);
1110                 f2fs_balance_fs(sbi, dn.node_changed);
1111         }
1112 out:
1113         trace_f2fs_map_blocks(inode, map, err);
1114         return err;
1115 }
1116
1117 static int __get_data_block(struct inode *inode, sector_t iblock,
1118                         struct buffer_head *bh, int create, int flag,
1119                         pgoff_t *next_pgofs, int seg_type)
1120 {
1121         struct f2fs_map_blocks map;
1122         int err;
1123
1124         map.m_lblk = iblock;
1125         map.m_len = bh->b_size >> inode->i_blkbits;
1126         map.m_next_pgofs = next_pgofs;
1127         map.m_next_extent = NULL;
1128         map.m_seg_type = seg_type;
1129
1130         err = f2fs_map_blocks(inode, &map, create, flag);
1131         if (!err) {
1132                 map_bh(bh, inode->i_sb, map.m_pblk);
1133                 bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
1134                 bh->b_size = (u64)map.m_len << inode->i_blkbits;
1135         }
1136         return err;
1137 }
1138
1139 static int get_data_block(struct inode *inode, sector_t iblock,
1140                         struct buffer_head *bh_result, int create, int flag,
1141                         pgoff_t *next_pgofs)
1142 {
1143         return __get_data_block(inode, iblock, bh_result, create,
1144                                                         flag, next_pgofs,
1145                                                         NO_CHECK_TYPE);
1146 }
1147
1148 static int get_data_block_dio(struct inode *inode, sector_t iblock,
1149                         struct buffer_head *bh_result, int create)
1150 {
1151         return __get_data_block(inode, iblock, bh_result, create,
1152                                                 F2FS_GET_BLOCK_DEFAULT, NULL,
1153                                                 rw_hint_to_seg_type(
1154                                                         inode->i_write_hint));
1155 }
1156
1157 static int get_data_block_bmap(struct inode *inode, sector_t iblock,
1158                         struct buffer_head *bh_result, int create)
1159 {
1160         /* Block number less than F2FS MAX BLOCKS */
1161         if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
1162                 return -EFBIG;
1163
1164         return __get_data_block(inode, iblock, bh_result, create,
1165                                                 F2FS_GET_BLOCK_BMAP, NULL,
1166                                                 NO_CHECK_TYPE);
1167 }
1168
1169 static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
1170 {
1171         return (offset >> inode->i_blkbits);
1172 }
1173
1174 static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
1175 {
1176         return (blk << inode->i_blkbits);
1177 }
1178
1179 static int f2fs_xattr_fiemap(struct inode *inode,
1180                                 struct fiemap_extent_info *fieinfo)
1181 {
1182         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1183         struct page *page;
1184         struct node_info ni;
1185         __u64 phys = 0, len;
1186         __u32 flags;
1187         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
1188         int err = 0;
1189
1190         if (f2fs_has_inline_xattr(inode)) {
1191                 int offset;
1192
1193                 page = f2fs_grab_cache_page(NODE_MAPPING(sbi),
1194                                                 inode->i_ino, false);
1195                 if (!page)
1196                         return -ENOMEM;
1197
1198                 get_node_info(sbi, inode->i_ino, &ni);
1199
1200                 phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1201                 offset = offsetof(struct f2fs_inode, i_addr) +
1202                                         sizeof(__le32) * (DEF_ADDRS_PER_INODE -
1203                                         get_inline_xattr_addrs(inode));
1204
1205                 phys += offset;
1206                 len = inline_xattr_size(inode);
1207
1208                 f2fs_put_page(page, 1);
1209
1210                 flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED;
1211
1212                 if (!xnid)
1213                         flags |= FIEMAP_EXTENT_LAST;
1214
1215                 err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1216                 if (err || err == 1)
1217                         return err;
1218         }
1219
1220         if (xnid) {
1221                 page = f2fs_grab_cache_page(NODE_MAPPING(sbi), xnid, false);
1222                 if (!page)
1223                         return -ENOMEM;
1224
1225                 get_node_info(sbi, xnid, &ni);
1226
1227                 phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1228                 len = inode->i_sb->s_blocksize;
1229
1230                 f2fs_put_page(page, 1);
1231
1232                 flags = FIEMAP_EXTENT_LAST;
1233         }
1234
1235         if (phys)
1236                 err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1237
1238         return (err < 0 ? err : 0);
1239 }
1240
1241 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1242                 u64 start, u64 len)
1243 {
1244         struct buffer_head map_bh;
1245         sector_t start_blk, last_blk;
1246         pgoff_t next_pgofs;
1247         u64 logical = 0, phys = 0, size = 0;
1248         u32 flags = 0;
1249         int ret = 0;
1250
1251         if (fieinfo->fi_flags & FIEMAP_FLAG_CACHE) {
1252                 ret = f2fs_precache_extents(inode);
1253                 if (ret)
1254                         return ret;
1255         }
1256
1257         ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR);
1258         if (ret)
1259                 return ret;
1260
1261         inode_lock(inode);
1262
1263         if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
1264                 ret = f2fs_xattr_fiemap(inode, fieinfo);
1265                 goto out;
1266         }
1267
1268         if (f2fs_has_inline_data(inode)) {
1269                 ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
1270                 if (ret != -EAGAIN)
1271                         goto out;
1272         }
1273
1274         if (logical_to_blk(inode, len) == 0)
1275                 len = blk_to_logical(inode, 1);
1276
1277         start_blk = logical_to_blk(inode, start);
1278         last_blk = logical_to_blk(inode, start + len - 1);
1279
1280 next:
1281         memset(&map_bh, 0, sizeof(struct buffer_head));
1282         map_bh.b_size = len;
1283
1284         ret = get_data_block(inode, start_blk, &map_bh, 0,
1285                                         F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
1286         if (ret)
1287                 goto out;
1288
1289         /* HOLE */
1290         if (!buffer_mapped(&map_bh)) {
1291                 start_blk = next_pgofs;
1292
1293                 if (blk_to_logical(inode, start_blk) < blk_to_logical(inode,
1294                                         F2FS_I_SB(inode)->max_file_blocks))
1295                         goto prep_next;
1296
1297                 flags |= FIEMAP_EXTENT_LAST;
1298         }
1299
1300         if (size) {
1301                 if (f2fs_encrypted_inode(inode))
1302                         flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
1303
1304                 ret = fiemap_fill_next_extent(fieinfo, logical,
1305                                 phys, size, flags);
1306         }
1307
1308         if (start_blk > last_blk || ret)
1309                 goto out;
1310
1311         logical = blk_to_logical(inode, start_blk);
1312         phys = blk_to_logical(inode, map_bh.b_blocknr);
1313         size = map_bh.b_size;
1314         flags = 0;
1315         if (buffer_unwritten(&map_bh))
1316                 flags = FIEMAP_EXTENT_UNWRITTEN;
1317
1318         start_blk += logical_to_blk(inode, size);
1319
1320 prep_next:
1321         cond_resched();
1322         if (fatal_signal_pending(current))
1323                 ret = -EINTR;
1324         else
1325                 goto next;
1326 out:
1327         if (ret == 1)
1328                 ret = 0;
1329
1330         inode_unlock(inode);
1331         return ret;
1332 }
1333
1334 /*
1335  * This function was originally taken from fs/mpage.c, and customized for f2fs.
1336  * Major change was from block_size == page_size in f2fs by default.
1337  */
1338 static int f2fs_mpage_readpages(struct address_space *mapping,
1339                         struct list_head *pages, struct page *page,
1340                         unsigned nr_pages)
1341 {
1342         struct bio *bio = NULL;
1343         sector_t last_block_in_bio = 0;
1344         struct inode *inode = mapping->host;
1345         const unsigned blkbits = inode->i_blkbits;
1346         const unsigned blocksize = 1 << blkbits;
1347         sector_t block_in_file;
1348         sector_t last_block;
1349         sector_t last_block_in_file;
1350         sector_t block_nr;
1351         struct f2fs_map_blocks map;
1352
1353         map.m_pblk = 0;
1354         map.m_lblk = 0;
1355         map.m_len = 0;
1356         map.m_flags = 0;
1357         map.m_next_pgofs = NULL;
1358         map.m_next_extent = NULL;
1359         map.m_seg_type = NO_CHECK_TYPE;
1360
1361         for (; nr_pages; nr_pages--) {
1362                 if (pages) {
1363                         page = list_last_entry(pages, struct page, lru);
1364
1365                         prefetchw(&page->flags);
1366                         list_del(&page->lru);
1367                         if (add_to_page_cache_lru(page, mapping,
1368                                                   page->index,
1369                                                   readahead_gfp_mask(mapping)))
1370                                 goto next_page;
1371                 }
1372
1373                 block_in_file = (sector_t)page->index;
1374                 last_block = block_in_file + nr_pages;
1375                 last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
1376                                                                 blkbits;
1377                 if (last_block > last_block_in_file)
1378                         last_block = last_block_in_file;
1379
1380                 /*
1381                  * Map blocks using the previous result first.
1382                  */
1383                 if ((map.m_flags & F2FS_MAP_MAPPED) &&
1384                                 block_in_file > map.m_lblk &&
1385                                 block_in_file < (map.m_lblk + map.m_len))
1386                         goto got_it;
1387
1388                 /*
1389                  * Then do more f2fs_map_blocks() calls until we are
1390                  * done with this page.
1391                  */
1392                 map.m_flags = 0;
1393
1394                 if (block_in_file < last_block) {
1395                         map.m_lblk = block_in_file;
1396                         map.m_len = last_block - block_in_file;
1397
1398                         if (f2fs_map_blocks(inode, &map, 0,
1399                                                 F2FS_GET_BLOCK_DEFAULT))
1400                                 goto set_error_page;
1401                 }
1402 got_it:
1403                 if ((map.m_flags & F2FS_MAP_MAPPED)) {
1404                         block_nr = map.m_pblk + block_in_file - map.m_lblk;
1405                         SetPageMappedToDisk(page);
1406
1407                         if (!PageUptodate(page) && !cleancache_get_page(page)) {
1408                                 SetPageUptodate(page);
1409                                 goto confused;
1410                         }
1411                 } else {
1412                         zero_user_segment(page, 0, PAGE_SIZE);
1413                         if (!PageUptodate(page))
1414                                 SetPageUptodate(page);
1415                         unlock_page(page);
1416                         goto next_page;
1417                 }
1418
1419                 /*
1420                  * This page will go to BIO.  Do we need to send this
1421                  * BIO off first?
1422                  */
1423                 if (bio && (last_block_in_bio != block_nr - 1 ||
1424                         !__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
1425 submit_and_realloc:
1426                         __submit_bio(F2FS_I_SB(inode), bio, DATA);
1427                         bio = NULL;
1428                 }
1429                 if (bio == NULL) {
1430                         bio = f2fs_grab_read_bio(inode, block_nr, nr_pages);
1431                         if (IS_ERR(bio)) {
1432                                 bio = NULL;
1433                                 goto set_error_page;
1434                         }
1435                 }
1436
1437                 if (bio_add_page(bio, page, blocksize, 0) < blocksize)
1438                         goto submit_and_realloc;
1439
1440                 last_block_in_bio = block_nr;
1441                 goto next_page;
1442 set_error_page:
1443                 SetPageError(page);
1444                 zero_user_segment(page, 0, PAGE_SIZE);
1445                 unlock_page(page);
1446                 goto next_page;
1447 confused:
1448                 if (bio) {
1449                         __submit_bio(F2FS_I_SB(inode), bio, DATA);
1450                         bio = NULL;
1451                 }
1452                 unlock_page(page);
1453 next_page:
1454                 if (pages)
1455                         put_page(page);
1456         }
1457         BUG_ON(pages && !list_empty(pages));
1458         if (bio)
1459                 __submit_bio(F2FS_I_SB(inode), bio, DATA);
1460         return 0;
1461 }
1462
1463 static int f2fs_read_data_page(struct file *file, struct page *page)
1464 {
1465         struct inode *inode = page->mapping->host;
1466         int ret = -EAGAIN;
1467
1468         trace_f2fs_readpage(page, DATA);
1469
1470         /* If the file has inline data, try to read it directly */
1471         if (f2fs_has_inline_data(inode))
1472                 ret = f2fs_read_inline_data(inode, page);
1473         if (ret == -EAGAIN)
1474                 ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
1475         return ret;
1476 }
1477
1478 static int f2fs_read_data_pages(struct file *file,
1479                         struct address_space *mapping,
1480                         struct list_head *pages, unsigned nr_pages)
1481 {
1482         struct inode *inode = mapping->host;
1483         struct page *page = list_last_entry(pages, struct page, lru);
1484
1485         trace_f2fs_readpages(inode, page, nr_pages);
1486
1487         /* If the file has inline data, skip readpages */
1488         if (f2fs_has_inline_data(inode))
1489                 return 0;
1490
1491         return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
1492 }
1493
1494 static int encrypt_one_page(struct f2fs_io_info *fio)
1495 {
1496         struct inode *inode = fio->page->mapping->host;
1497         gfp_t gfp_flags = GFP_NOFS;
1498
1499         if (!f2fs_encrypted_file(inode))
1500                 return 0;
1501
1502         /* wait for GCed encrypted page writeback */
1503         f2fs_wait_on_block_writeback(fio->sbi, fio->old_blkaddr);
1504
1505 retry_encrypt:
1506         fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
1507                         PAGE_SIZE, 0, fio->page->index, gfp_flags);
1508         if (!IS_ERR(fio->encrypted_page))
1509                 return 0;
1510
1511         /* flush pending IOs and wait for a while in the ENOMEM case */
1512         if (PTR_ERR(fio->encrypted_page) == -ENOMEM) {
1513                 f2fs_flush_merged_writes(fio->sbi);
1514                 congestion_wait(BLK_RW_ASYNC, HZ/50);
1515                 gfp_flags |= __GFP_NOFAIL;
1516                 goto retry_encrypt;
1517         }
1518         return PTR_ERR(fio->encrypted_page);
1519 }
1520
1521 static inline bool check_inplace_update_policy(struct inode *inode,
1522                                 struct f2fs_io_info *fio)
1523 {
1524         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1525         unsigned int policy = SM_I(sbi)->ipu_policy;
1526
1527         if (policy & (0x1 << F2FS_IPU_FORCE))
1528                 return true;
1529         if (policy & (0x1 << F2FS_IPU_SSR) && need_SSR(sbi))
1530                 return true;
1531         if (policy & (0x1 << F2FS_IPU_UTIL) &&
1532                         utilization(sbi) > SM_I(sbi)->min_ipu_util)
1533                 return true;
1534         if (policy & (0x1 << F2FS_IPU_SSR_UTIL) && need_SSR(sbi) &&
1535                         utilization(sbi) > SM_I(sbi)->min_ipu_util)
1536                 return true;
1537
1538         /*
1539          * IPU for rewrite async pages
1540          */
1541         if (policy & (0x1 << F2FS_IPU_ASYNC) &&
1542                         fio && fio->op == REQ_OP_WRITE &&
1543                         !(fio->op_flags & REQ_SYNC) &&
1544                         !f2fs_encrypted_inode(inode))
1545                 return true;
1546
1547         /* this is only set during fdatasync */
1548         if (policy & (0x1 << F2FS_IPU_FSYNC) &&
1549                         is_inode_flag_set(inode, FI_NEED_IPU))
1550                 return true;
1551
1552         return false;
1553 }
1554
1555 bool should_update_inplace(struct inode *inode, struct f2fs_io_info *fio)
1556 {
1557         if (f2fs_is_pinned_file(inode))
1558                 return true;
1559
1560         /* if this is cold file, we should overwrite to avoid fragmentation */
1561         if (file_is_cold(inode))
1562                 return true;
1563
1564         return check_inplace_update_policy(inode, fio);
1565 }
1566
1567 bool should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
1568 {
1569         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1570
1571         if (test_opt(sbi, LFS))
1572                 return true;
1573         if (S_ISDIR(inode->i_mode))
1574                 return true;
1575         if (f2fs_is_atomic_file(inode))
1576                 return true;
1577         if (fio) {
1578                 if (is_cold_data(fio->page))
1579                         return true;
1580                 if (IS_ATOMIC_WRITTEN_PAGE(fio->page))
1581                         return true;
1582         }
1583         return false;
1584 }
1585
1586 static inline bool need_inplace_update(struct f2fs_io_info *fio)
1587 {
1588         struct inode *inode = fio->page->mapping->host;
1589
1590         if (should_update_outplace(inode, fio))
1591                 return false;
1592
1593         return should_update_inplace(inode, fio);
1594 }
1595
1596 static inline bool valid_ipu_blkaddr(struct f2fs_io_info *fio)
1597 {
1598         if (fio->old_blkaddr == NEW_ADDR)
1599                 return false;
1600         if (fio->old_blkaddr == NULL_ADDR)
1601                 return false;
1602         return true;
1603 }
1604
1605 int do_write_data_page(struct f2fs_io_info *fio)
1606 {
1607         struct page *page = fio->page;
1608         struct inode *inode = page->mapping->host;
1609         struct dnode_of_data dn;
1610         struct extent_info ei = {0,0,0};
1611         bool ipu_force = false;
1612         int err = 0;
1613
1614         set_new_dnode(&dn, inode, NULL, NULL, 0);
1615         if (need_inplace_update(fio) &&
1616                         f2fs_lookup_extent_cache(inode, page->index, &ei)) {
1617                 fio->old_blkaddr = ei.blk + page->index - ei.fofs;
1618
1619                 if (valid_ipu_blkaddr(fio)) {
1620                         ipu_force = true;
1621                         fio->need_lock = LOCK_DONE;
1622                         goto got_it;
1623                 }
1624         }
1625
1626         /* Deadlock due to between page->lock and f2fs_lock_op */
1627         if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi))
1628                 return -EAGAIN;
1629
1630         err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1631         if (err)
1632                 goto out;
1633
1634         fio->old_blkaddr = dn.data_blkaddr;
1635
1636         /* This page is already truncated */
1637         if (fio->old_blkaddr == NULL_ADDR) {
1638                 ClearPageUptodate(page);
1639                 goto out_writepage;
1640         }
1641 got_it:
1642         /*
1643          * If current allocation needs SSR,
1644          * it had better in-place writes for updated data.
1645          */
1646         if (ipu_force || (valid_ipu_blkaddr(fio) && need_inplace_update(fio))) {
1647                 err = encrypt_one_page(fio);
1648                 if (err)
1649                         goto out_writepage;
1650
1651                 set_page_writeback(page);
1652                 f2fs_put_dnode(&dn);
1653                 if (fio->need_lock == LOCK_REQ)
1654                         f2fs_unlock_op(fio->sbi);
1655                 err = rewrite_data_page(fio);
1656                 trace_f2fs_do_write_data_page(fio->page, IPU);
1657                 set_inode_flag(inode, FI_UPDATE_WRITE);
1658                 return err;
1659         }
1660
1661         if (fio->need_lock == LOCK_RETRY) {
1662                 if (!f2fs_trylock_op(fio->sbi)) {
1663                         err = -EAGAIN;
1664                         goto out_writepage;
1665                 }
1666                 fio->need_lock = LOCK_REQ;
1667         }
1668
1669         err = encrypt_one_page(fio);
1670         if (err)
1671                 goto out_writepage;
1672
1673         set_page_writeback(page);
1674
1675         /* LFS mode write path */
1676         write_data_page(&dn, fio);
1677         trace_f2fs_do_write_data_page(page, OPU);
1678         set_inode_flag(inode, FI_APPEND_WRITE);
1679         if (page->index == 0)
1680                 set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1681 out_writepage:
1682         f2fs_put_dnode(&dn);
1683 out:
1684         if (fio->need_lock == LOCK_REQ)
1685                 f2fs_unlock_op(fio->sbi);
1686         return err;
1687 }
1688
1689 static int __write_data_page(struct page *page, bool *submitted,
1690                                 struct writeback_control *wbc,
1691                                 enum iostat_type io_type)
1692 {
1693         struct inode *inode = page->mapping->host;
1694         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1695         loff_t i_size = i_size_read(inode);
1696         const pgoff_t end_index = ((unsigned long long) i_size)
1697                                                         >> PAGE_SHIFT;
1698         loff_t psize = (page->index + 1) << PAGE_SHIFT;
1699         unsigned offset = 0;
1700         bool need_balance_fs = false;
1701         int err = 0;
1702         struct f2fs_io_info fio = {
1703                 .sbi = sbi,
1704                 .ino = inode->i_ino,
1705                 .type = DATA,
1706                 .op = REQ_OP_WRITE,
1707                 .op_flags = wbc_to_write_flags(wbc),
1708                 .old_blkaddr = NULL_ADDR,
1709                 .page = page,
1710                 .encrypted_page = NULL,
1711                 .submitted = false,
1712                 .need_lock = LOCK_RETRY,
1713                 .io_type = io_type,
1714                 .io_wbc = wbc,
1715         };
1716
1717         trace_f2fs_writepage(page, DATA);
1718
1719         /* we should bypass data pages to proceed the kworkder jobs */
1720         if (unlikely(f2fs_cp_error(sbi))) {
1721                 mapping_set_error(page->mapping, -EIO);
1722                 goto out;
1723         }
1724
1725         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1726                 goto redirty_out;
1727
1728         if (page->index < end_index)
1729                 goto write;
1730
1731         /*
1732          * If the offset is out-of-range of file size,
1733          * this page does not have to be written to disk.
1734          */
1735         offset = i_size & (PAGE_SIZE - 1);
1736         if ((page->index >= end_index + 1) || !offset)
1737                 goto out;
1738
1739         zero_user_segment(page, offset, PAGE_SIZE);
1740 write:
1741         if (f2fs_is_drop_cache(inode))
1742                 goto out;
1743         /* we should not write 0'th page having journal header */
1744         if (f2fs_is_volatile_file(inode) && (!page->index ||
1745                         (!wbc->for_reclaim &&
1746                         available_free_memory(sbi, BASE_CHECK))))
1747                 goto redirty_out;
1748
1749         /* Dentry blocks are controlled by checkpoint */
1750         if (S_ISDIR(inode->i_mode)) {
1751                 fio.need_lock = LOCK_DONE;
1752                 err = do_write_data_page(&fio);
1753                 goto done;
1754         }
1755
1756         if (!wbc->for_reclaim)
1757                 need_balance_fs = true;
1758         else if (has_not_enough_free_secs(sbi, 0, 0))
1759                 goto redirty_out;
1760         else
1761                 set_inode_flag(inode, FI_HOT_DATA);
1762
1763         err = -EAGAIN;
1764         if (f2fs_has_inline_data(inode)) {
1765                 err = f2fs_write_inline_data(inode, page);
1766                 if (!err)
1767                         goto out;
1768         }
1769
1770         if (err == -EAGAIN) {
1771                 err = do_write_data_page(&fio);
1772                 if (err == -EAGAIN) {
1773                         fio.need_lock = LOCK_REQ;
1774                         err = do_write_data_page(&fio);
1775                 }
1776         }
1777
1778         if (err) {
1779                 file_set_keep_isize(inode);
1780         } else {
1781                 down_write(&F2FS_I(inode)->i_sem);
1782                 if (F2FS_I(inode)->last_disk_size < psize)
1783                         F2FS_I(inode)->last_disk_size = psize;
1784                 up_write(&F2FS_I(inode)->i_sem);
1785         }
1786
1787 done:
1788         if (err && err != -ENOENT)
1789                 goto redirty_out;
1790
1791 out:
1792         inode_dec_dirty_pages(inode);
1793         if (err)
1794                 ClearPageUptodate(page);
1795
1796         if (wbc->for_reclaim) {
1797                 f2fs_submit_merged_write_cond(sbi, inode, 0, page->index, DATA);
1798                 clear_inode_flag(inode, FI_HOT_DATA);
1799                 remove_dirty_inode(inode);
1800                 submitted = NULL;
1801         }
1802
1803         unlock_page(page);
1804         if (!S_ISDIR(inode->i_mode))
1805                 f2fs_balance_fs(sbi, need_balance_fs);
1806
1807         if (unlikely(f2fs_cp_error(sbi))) {
1808                 f2fs_submit_merged_write(sbi, DATA);
1809                 submitted = NULL;
1810         }
1811
1812         if (submitted)
1813                 *submitted = fio.submitted;
1814
1815         return 0;
1816
1817 redirty_out:
1818         redirty_page_for_writepage(wbc, page);
1819         if (!err)
1820                 return AOP_WRITEPAGE_ACTIVATE;
1821         unlock_page(page);
1822         return err;
1823 }
1824
1825 static int f2fs_write_data_page(struct page *page,
1826                                         struct writeback_control *wbc)
1827 {
1828         return __write_data_page(page, NULL, wbc, FS_DATA_IO);
1829 }
1830
1831 /*
1832  * This function was copied from write_cche_pages from mm/page-writeback.c.
1833  * The major change is making write step of cold data page separately from
1834  * warm/hot data page.
1835  */
1836 static int f2fs_write_cache_pages(struct address_space *mapping,
1837                                         struct writeback_control *wbc,
1838                                         enum iostat_type io_type)
1839 {
1840         int ret = 0;
1841         int done = 0;
1842         struct pagevec pvec;
1843         int nr_pages;
1844         pgoff_t uninitialized_var(writeback_index);
1845         pgoff_t index;
1846         pgoff_t end;            /* Inclusive */
1847         pgoff_t done_index;
1848         pgoff_t last_idx = ULONG_MAX;
1849         int cycled;
1850         int range_whole = 0;
1851         int tag;
1852
1853         pagevec_init(&pvec);
1854
1855         if (get_dirty_pages(mapping->host) <=
1856                                 SM_I(F2FS_M_SB(mapping))->min_hot_blocks)
1857                 set_inode_flag(mapping->host, FI_HOT_DATA);
1858         else
1859                 clear_inode_flag(mapping->host, FI_HOT_DATA);
1860
1861         if (wbc->range_cyclic) {
1862                 writeback_index = mapping->writeback_index; /* prev offset */
1863                 index = writeback_index;
1864                 if (index == 0)
1865                         cycled = 1;
1866                 else
1867                         cycled = 0;
1868                 end = -1;
1869         } else {
1870                 index = wbc->range_start >> PAGE_SHIFT;
1871                 end = wbc->range_end >> PAGE_SHIFT;
1872                 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1873                         range_whole = 1;
1874                 cycled = 1; /* ignore range_cyclic tests */
1875         }
1876         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1877                 tag = PAGECACHE_TAG_TOWRITE;
1878         else
1879                 tag = PAGECACHE_TAG_DIRTY;
1880 retry:
1881         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1882                 tag_pages_for_writeback(mapping, index, end);
1883         done_index = index;
1884         while (!done && (index <= end)) {
1885                 int i;
1886
1887                 nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
1888                                 tag);
1889                 if (nr_pages == 0)
1890                         break;
1891
1892                 for (i = 0; i < nr_pages; i++) {
1893                         struct page *page = pvec.pages[i];
1894                         bool submitted = false;
1895
1896                         done_index = page->index;
1897 retry_write:
1898                         lock_page(page);
1899
1900                         if (unlikely(page->mapping != mapping)) {
1901 continue_unlock:
1902                                 unlock_page(page);
1903                                 continue;
1904                         }
1905
1906                         if (!PageDirty(page)) {
1907                                 /* someone wrote it for us */
1908                                 goto continue_unlock;
1909                         }
1910
1911                         if (PageWriteback(page)) {
1912                                 if (wbc->sync_mode != WB_SYNC_NONE)
1913                                         f2fs_wait_on_page_writeback(page,
1914                                                                 DATA, true);
1915                                 else
1916                                         goto continue_unlock;
1917                         }
1918
1919                         BUG_ON(PageWriteback(page));
1920                         if (!clear_page_dirty_for_io(page))
1921                                 goto continue_unlock;
1922
1923                         ret = __write_data_page(page, &submitted, wbc, io_type);
1924                         if (unlikely(ret)) {
1925                                 /*
1926                                  * keep nr_to_write, since vfs uses this to
1927                                  * get # of written pages.
1928                                  */
1929                                 if (ret == AOP_WRITEPAGE_ACTIVATE) {
1930                                         unlock_page(page);
1931                                         ret = 0;
1932                                         continue;
1933                                 } else if (ret == -EAGAIN) {
1934                                         ret = 0;
1935                                         if (wbc->sync_mode == WB_SYNC_ALL) {
1936                                                 cond_resched();
1937                                                 congestion_wait(BLK_RW_ASYNC,
1938                                                                         HZ/50);
1939                                                 goto retry_write;
1940                                         }
1941                                         continue;
1942                                 }
1943                                 done_index = page->index + 1;
1944                                 done = 1;
1945                                 break;
1946                         } else if (submitted) {
1947                                 last_idx = page->index;
1948                         }
1949
1950                         /* give a priority to WB_SYNC threads */
1951                         if ((atomic_read(&F2FS_M_SB(mapping)->wb_sync_req) ||
1952                                         --wbc->nr_to_write <= 0) &&
1953                                         wbc->sync_mode == WB_SYNC_NONE) {
1954                                 done = 1;
1955                                 break;
1956                         }
1957                 }
1958                 pagevec_release(&pvec);
1959                 cond_resched();
1960         }
1961
1962         if (!cycled && !done) {
1963                 cycled = 1;
1964                 index = 0;
1965                 end = writeback_index - 1;
1966                 goto retry;
1967         }
1968         if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1969                 mapping->writeback_index = done_index;
1970
1971         if (last_idx != ULONG_MAX)
1972                 f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
1973                                                 0, last_idx, DATA);
1974
1975         return ret;
1976 }
1977
1978 int __f2fs_write_data_pages(struct address_space *mapping,
1979                                                 struct writeback_control *wbc,
1980                                                 enum iostat_type io_type)
1981 {
1982         struct inode *inode = mapping->host;
1983         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1984         struct blk_plug plug;
1985         int ret;
1986
1987         /* deal with chardevs and other special file */
1988         if (!mapping->a_ops->writepage)
1989                 return 0;
1990
1991         /* skip writing if there is no dirty page in this inode */
1992         if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
1993                 return 0;
1994
1995         /* during POR, we don't need to trigger writepage at all. */
1996         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1997                 goto skip_write;
1998
1999         if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
2000                         get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
2001                         available_free_memory(sbi, DIRTY_DENTS))
2002                 goto skip_write;
2003
2004         /* skip writing during file defragment */
2005         if (is_inode_flag_set(inode, FI_DO_DEFRAG))
2006                 goto skip_write;
2007
2008         trace_f2fs_writepages(mapping->host, wbc, DATA);
2009
2010         /* to avoid spliting IOs due to mixed WB_SYNC_ALL and WB_SYNC_NONE */
2011         if (wbc->sync_mode == WB_SYNC_ALL)
2012                 atomic_inc(&sbi->wb_sync_req);
2013         else if (atomic_read(&sbi->wb_sync_req))
2014                 goto skip_write;
2015
2016         blk_start_plug(&plug);
2017         ret = f2fs_write_cache_pages(mapping, wbc, io_type);
2018         blk_finish_plug(&plug);
2019
2020         if (wbc->sync_mode == WB_SYNC_ALL)
2021                 atomic_dec(&sbi->wb_sync_req);
2022         /*
2023          * if some pages were truncated, we cannot guarantee its mapping->host
2024          * to detect pending bios.
2025          */
2026
2027         remove_dirty_inode(inode);
2028         return ret;
2029
2030 skip_write:
2031         wbc->pages_skipped += get_dirty_pages(inode);
2032         trace_f2fs_writepages(mapping->host, wbc, DATA);
2033         return 0;
2034 }
2035
2036 static int f2fs_write_data_pages(struct address_space *mapping,
2037                             struct writeback_control *wbc)
2038 {
2039         struct inode *inode = mapping->host;
2040
2041         return __f2fs_write_data_pages(mapping, wbc,
2042                         F2FS_I(inode)->cp_task == current ?
2043                         FS_CP_DATA_IO : FS_DATA_IO);
2044 }
2045
2046 static void f2fs_write_failed(struct address_space *mapping, loff_t to)
2047 {
2048         struct inode *inode = mapping->host;
2049         loff_t i_size = i_size_read(inode);
2050
2051         if (to > i_size) {
2052                 down_write(&F2FS_I(inode)->i_mmap_sem);
2053                 truncate_pagecache(inode, i_size);
2054                 truncate_blocks(inode, i_size, true);
2055                 up_write(&F2FS_I(inode)->i_mmap_sem);
2056         }
2057 }
2058
2059 static int prepare_write_begin(struct f2fs_sb_info *sbi,
2060                         struct page *page, loff_t pos, unsigned len,
2061                         block_t *blk_addr, bool *node_changed)
2062 {
2063         struct inode *inode = page->mapping->host;
2064         pgoff_t index = page->index;
2065         struct dnode_of_data dn;
2066         struct page *ipage;
2067         bool locked = false;
2068         struct extent_info ei = {0,0,0};
2069         int err = 0;
2070
2071         /*
2072          * we already allocated all the blocks, so we don't need to get
2073          * the block addresses when there is no need to fill the page.
2074          */
2075         if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
2076                         !is_inode_flag_set(inode, FI_NO_PREALLOC))
2077                 return 0;
2078
2079         if (f2fs_has_inline_data(inode) ||
2080                         (pos & PAGE_MASK) >= i_size_read(inode)) {
2081                 __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
2082                 locked = true;
2083         }
2084 restart:
2085         /* check inline_data */
2086         ipage = get_node_page(sbi, inode->i_ino);
2087         if (IS_ERR(ipage)) {
2088                 err = PTR_ERR(ipage);
2089                 goto unlock_out;
2090         }
2091
2092         set_new_dnode(&dn, inode, ipage, ipage, 0);
2093
2094         if (f2fs_has_inline_data(inode)) {
2095                 if (pos + len <= MAX_INLINE_DATA(inode)) {
2096                         read_inline_data(page, ipage);
2097                         set_inode_flag(inode, FI_DATA_EXIST);
2098                         if (inode->i_nlink)
2099                                 set_inline_node(ipage);
2100                 } else {
2101                         err = f2fs_convert_inline_page(&dn, page);
2102                         if (err)
2103                                 goto out;
2104                         if (dn.data_blkaddr == NULL_ADDR)
2105                                 err = f2fs_get_block(&dn, index);
2106                 }
2107         } else if (locked) {
2108                 err = f2fs_get_block(&dn, index);
2109         } else {
2110                 if (f2fs_lookup_extent_cache(inode, index, &ei)) {
2111                         dn.data_blkaddr = ei.blk + index - ei.fofs;
2112                 } else {
2113                         /* hole case */
2114                         err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
2115                         if (err || dn.data_blkaddr == NULL_ADDR) {
2116                                 f2fs_put_dnode(&dn);
2117                                 __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO,
2118                                                                 true);
2119                                 locked = true;
2120                                 goto restart;
2121                         }
2122                 }
2123         }
2124
2125         /* convert_inline_page can make node_changed */
2126         *blk_addr = dn.data_blkaddr;
2127         *node_changed = dn.node_changed;
2128 out:
2129         f2fs_put_dnode(&dn);
2130 unlock_out:
2131         if (locked)
2132                 __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
2133         return err;
2134 }
2135
2136 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
2137                 loff_t pos, unsigned len, unsigned flags,
2138                 struct page **pagep, void **fsdata)
2139 {
2140         struct inode *inode = mapping->host;
2141         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2142         struct page *page = NULL;
2143         pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
2144         bool need_balance = false, drop_atomic = false;
2145         block_t blkaddr = NULL_ADDR;
2146         int err = 0;
2147
2148         trace_f2fs_write_begin(inode, pos, len, flags);
2149
2150         if (f2fs_is_atomic_file(inode) &&
2151                         !available_free_memory(sbi, INMEM_PAGES)) {
2152                 err = -ENOMEM;
2153                 drop_atomic = true;
2154                 goto fail;
2155         }
2156
2157         /*
2158          * We should check this at this moment to avoid deadlock on inode page
2159          * and #0 page. The locking rule for inline_data conversion should be:
2160          * lock_page(page #0) -> lock_page(inode_page)
2161          */
2162         if (index != 0) {
2163                 err = f2fs_convert_inline_inode(inode);
2164                 if (err)
2165                         goto fail;
2166         }
2167 repeat:
2168         /*
2169          * Do not use grab_cache_page_write_begin() to avoid deadlock due to
2170          * wait_for_stable_page. Will wait that below with our IO control.
2171          */
2172         page = f2fs_pagecache_get_page(mapping, index,
2173                                 FGP_LOCK | FGP_WRITE | FGP_CREAT, GFP_NOFS);
2174         if (!page) {
2175                 err = -ENOMEM;
2176                 goto fail;
2177         }
2178
2179         *pagep = page;
2180
2181         err = prepare_write_begin(sbi, page, pos, len,
2182                                         &blkaddr, &need_balance);
2183         if (err)
2184                 goto fail;
2185
2186         if (need_balance && has_not_enough_free_secs(sbi, 0, 0)) {
2187                 unlock_page(page);
2188                 f2fs_balance_fs(sbi, true);
2189                 lock_page(page);
2190                 if (page->mapping != mapping) {
2191                         /* The page got truncated from under us */
2192                         f2fs_put_page(page, 1);
2193                         goto repeat;
2194                 }
2195         }
2196
2197         f2fs_wait_on_page_writeback(page, DATA, false);
2198
2199         /* wait for GCed encrypted page writeback */
2200         if (f2fs_encrypted_file(inode))
2201                 f2fs_wait_on_block_writeback(sbi, blkaddr);
2202
2203         if (len == PAGE_SIZE || PageUptodate(page))
2204                 return 0;
2205
2206         if (!(pos & (PAGE_SIZE - 1)) && (pos + len) >= i_size_read(inode)) {
2207                 zero_user_segment(page, len, PAGE_SIZE);
2208                 return 0;
2209         }
2210
2211         if (blkaddr == NEW_ADDR) {
2212                 zero_user_segment(page, 0, PAGE_SIZE);
2213                 SetPageUptodate(page);
2214         } else {
2215                 err = f2fs_submit_page_read(inode, page, blkaddr);
2216                 if (err)
2217                         goto fail;
2218
2219                 lock_page(page);
2220                 if (unlikely(page->mapping != mapping)) {
2221                         f2fs_put_page(page, 1);
2222                         goto repeat;
2223                 }
2224                 if (unlikely(!PageUptodate(page))) {
2225                         err = -EIO;
2226                         goto fail;
2227                 }
2228         }
2229         return 0;
2230
2231 fail:
2232         f2fs_put_page(page, 1);
2233         f2fs_write_failed(mapping, pos + len);
2234         if (drop_atomic)
2235                 drop_inmem_pages_all(sbi);
2236         return err;
2237 }
2238
2239 static int f2fs_write_end(struct file *file,
2240                         struct address_space *mapping,
2241                         loff_t pos, unsigned len, unsigned copied,
2242                         struct page *page, void *fsdata)
2243 {
2244         struct inode *inode = page->mapping->host;
2245
2246         trace_f2fs_write_end(inode, pos, len, copied);
2247
2248         /*
2249          * This should be come from len == PAGE_SIZE, and we expect copied
2250          * should be PAGE_SIZE. Otherwise, we treat it with zero copied and
2251          * let generic_perform_write() try to copy data again through copied=0.
2252          */
2253         if (!PageUptodate(page)) {
2254                 if (unlikely(copied != len))
2255                         copied = 0;
2256                 else
2257                         SetPageUptodate(page);
2258         }
2259         if (!copied)
2260                 goto unlock_out;
2261
2262         set_page_dirty(page);
2263
2264         if (pos + copied > i_size_read(inode))
2265                 f2fs_i_size_write(inode, pos + copied);
2266 unlock_out:
2267         f2fs_put_page(page, 1);
2268         f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
2269         return copied;
2270 }
2271
2272 static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
2273                            loff_t offset)
2274 {
2275         unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;
2276
2277         if (offset & blocksize_mask)
2278                 return -EINVAL;
2279
2280         if (iov_iter_alignment(iter) & blocksize_mask)
2281                 return -EINVAL;
2282
2283         return 0;
2284 }
2285
2286 static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
2287 {
2288         struct address_space *mapping = iocb->ki_filp->f_mapping;
2289         struct inode *inode = mapping->host;
2290         size_t count = iov_iter_count(iter);
2291         loff_t offset = iocb->ki_pos;
2292         int rw = iov_iter_rw(iter);
2293         int err;
2294
2295         err = check_direct_IO(inode, iter, offset);
2296         if (err)
2297                 return err;
2298
2299         if (__force_buffered_io(inode, rw))
2300                 return 0;
2301
2302         trace_f2fs_direct_IO_enter(inode, offset, count, rw);
2303
2304         down_read(&F2FS_I(inode)->dio_rwsem[rw]);
2305         err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
2306         up_read(&F2FS_I(inode)->dio_rwsem[rw]);
2307
2308         if (rw == WRITE) {
2309                 if (err > 0) {
2310                         f2fs_update_iostat(F2FS_I_SB(inode), APP_DIRECT_IO,
2311                                                                         err);
2312                         set_inode_flag(inode, FI_UPDATE_WRITE);
2313                 } else if (err < 0) {
2314                         f2fs_write_failed(mapping, offset + count);
2315                 }
2316         }
2317
2318         trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
2319
2320         return err;
2321 }
2322
2323 void f2fs_invalidate_page(struct page *page, unsigned int offset,
2324                                                         unsigned int length)
2325 {
2326         struct inode *inode = page->mapping->host;
2327         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2328
2329         if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
2330                 (offset % PAGE_SIZE || length != PAGE_SIZE))
2331                 return;
2332
2333         if (PageDirty(page)) {
2334                 if (inode->i_ino == F2FS_META_INO(sbi)) {
2335                         dec_page_count(sbi, F2FS_DIRTY_META);
2336                 } else if (inode->i_ino == F2FS_NODE_INO(sbi)) {
2337                         dec_page_count(sbi, F2FS_DIRTY_NODES);
2338                 } else {
2339                         inode_dec_dirty_pages(inode);
2340                         remove_dirty_inode(inode);
2341                 }
2342         }
2343
2344         /* This is atomic written page, keep Private */
2345         if (IS_ATOMIC_WRITTEN_PAGE(page))
2346                 return drop_inmem_page(inode, page);
2347
2348         set_page_private(page, 0);
2349         ClearPagePrivate(page);
2350 }
2351
2352 int f2fs_release_page(struct page *page, gfp_t wait)
2353 {
2354         /* If this is dirty page, keep PagePrivate */
2355         if (PageDirty(page))
2356                 return 0;
2357
2358         /* This is atomic written page, keep Private */
2359         if (IS_ATOMIC_WRITTEN_PAGE(page))
2360                 return 0;
2361
2362         set_page_private(page, 0);
2363         ClearPagePrivate(page);
2364         return 1;
2365 }
2366
2367 /*
2368  * This was copied from __set_page_dirty_buffers which gives higher performance
2369  * in very high speed storages. (e.g., pmem)
2370  */
2371 void f2fs_set_page_dirty_nobuffers(struct page *page)
2372 {
2373         struct address_space *mapping = page->mapping;
2374         unsigned long flags;
2375
2376         if (unlikely(!mapping))
2377                 return;
2378
2379         spin_lock(&mapping->private_lock);
2380         lock_page_memcg(page);
2381         SetPageDirty(page);
2382         spin_unlock(&mapping->private_lock);
2383
2384         spin_lock_irqsave(&mapping->tree_lock, flags);
2385         WARN_ON_ONCE(!PageUptodate(page));
2386         account_page_dirtied(page, mapping);
2387         radix_tree_tag_set(&mapping->page_tree,
2388                         page_index(page), PAGECACHE_TAG_DIRTY);
2389         spin_unlock_irqrestore(&mapping->tree_lock, flags);
2390         unlock_page_memcg(page);
2391
2392         __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
2393         return;
2394 }
2395
2396 static int f2fs_set_data_page_dirty(struct page *page)
2397 {
2398         struct address_space *mapping = page->mapping;
2399         struct inode *inode = mapping->host;
2400
2401         trace_f2fs_set_page_dirty(page, DATA);
2402
2403         if (!PageUptodate(page))
2404                 SetPageUptodate(page);
2405
2406         if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
2407                 if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
2408                         register_inmem_page(inode, page);
2409                         return 1;
2410                 }
2411                 /*
2412                  * Previously, this page has been registered, we just
2413                  * return here.
2414                  */
2415                 return 0;
2416         }
2417
2418         if (!PageDirty(page)) {
2419                 f2fs_set_page_dirty_nobuffers(page);
2420                 update_dirty_page(inode, page);
2421                 return 1;
2422         }
2423         return 0;
2424 }
2425
2426 static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
2427 {
2428         struct inode *inode = mapping->host;
2429
2430         if (f2fs_has_inline_data(inode))
2431                 return 0;
2432
2433         /* make sure allocating whole blocks */
2434         if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
2435                 filemap_write_and_wait(mapping);
2436
2437         return generic_block_bmap(mapping, block, get_data_block_bmap);
2438 }
2439
2440 #ifdef CONFIG_MIGRATION
2441 #include <linux/migrate.h>
2442
2443 int f2fs_migrate_page(struct address_space *mapping,
2444                 struct page *newpage, struct page *page, enum migrate_mode mode)
2445 {
2446         int rc, extra_count;
2447         struct f2fs_inode_info *fi = F2FS_I(mapping->host);
2448         bool atomic_written = IS_ATOMIC_WRITTEN_PAGE(page);
2449
2450         BUG_ON(PageWriteback(page));
2451
2452         /* migrating an atomic written page is safe with the inmem_lock hold */
2453         if (atomic_written) {
2454                 if (mode != MIGRATE_SYNC)
2455                         return -EBUSY;
2456                 if (!mutex_trylock(&fi->inmem_lock))
2457                         return -EAGAIN;
2458         }
2459
2460         /*
2461          * A reference is expected if PagePrivate set when move mapping,
2462          * however F2FS breaks this for maintaining dirty page counts when
2463          * truncating pages. So here adjusting the 'extra_count' make it work.
2464          */
2465         extra_count = (atomic_written ? 1 : 0) - page_has_private(page);
2466         rc = migrate_page_move_mapping(mapping, newpage,
2467                                 page, NULL, mode, extra_count);
2468         if (rc != MIGRATEPAGE_SUCCESS) {
2469                 if (atomic_written)
2470                         mutex_unlock(&fi->inmem_lock);
2471                 return rc;
2472         }
2473
2474         if (atomic_written) {
2475                 struct inmem_pages *cur;
2476                 list_for_each_entry(cur, &fi->inmem_pages, list)
2477                         if (cur->page == page) {
2478                                 cur->page = newpage;
2479                                 break;
2480                         }
2481                 mutex_unlock(&fi->inmem_lock);
2482                 put_page(page);
2483                 get_page(newpage);
2484         }
2485
2486         if (PagePrivate(page))
2487                 SetPagePrivate(newpage);
2488         set_page_private(newpage, page_private(page));
2489
2490         if (mode != MIGRATE_SYNC_NO_COPY)
2491                 migrate_page_copy(newpage, page);
2492         else
2493                 migrate_page_states(newpage, page);
2494
2495         return MIGRATEPAGE_SUCCESS;
2496 }
2497 #endif
2498
2499 const struct address_space_operations f2fs_dblock_aops = {
2500         .readpage       = f2fs_read_data_page,
2501         .readpages      = f2fs_read_data_pages,
2502         .writepage      = f2fs_write_data_page,
2503         .writepages     = f2fs_write_data_pages,
2504         .write_begin    = f2fs_write_begin,
2505         .write_end      = f2fs_write_end,
2506         .set_page_dirty = f2fs_set_data_page_dirty,
2507         .invalidatepage = f2fs_invalidate_page,
2508         .releasepage    = f2fs_release_page,
2509         .direct_IO      = f2fs_direct_IO,
2510         .bmap           = f2fs_bmap,
2511 #ifdef CONFIG_MIGRATION
2512         .migratepage    = f2fs_migrate_page,
2513 #endif
2514 };