xref: /openbmc/linux/fs/f2fs/data.c (revision 4354994f097d068a894aa1a0860da54571df3582)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * fs/f2fs/data.c
4  *
5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6  *             http://www.samsung.com/
7  */
8 #include <linux/fs.h>
9 #include <linux/f2fs_fs.h>
10 #include <linux/buffer_head.h>
11 #include <linux/mpage.h>
12 #include <linux/writeback.h>
13 #include <linux/backing-dev.h>
14 #include <linux/pagevec.h>
15 #include <linux/blkdev.h>
16 #include <linux/bio.h>
17 #include <linux/prefetch.h>
18 #include <linux/uio.h>
19 #include <linux/cleancache.h>
20 #include <linux/sched/signal.h>
21 
22 #include "f2fs.h"
23 #include "node.h"
24 #include "segment.h"
25 #include "trace.h"
26 #include <trace/events/f2fs.h>
27 
28 #define NUM_PREALLOC_POST_READ_CTXS	128
29 
30 static struct kmem_cache *bio_post_read_ctx_cache;
31 static mempool_t *bio_post_read_ctx_pool;
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 			(S_ISREG(inode->i_mode) &&
49 			is_inode_flag_set(inode, FI_ATOMIC_FILE)) ||
50 			is_cold_data(page))
51 		return true;
52 	return false;
53 }
54 
55 /* postprocessing steps for read bios */
56 enum bio_post_read_step {
57 	STEP_INITIAL = 0,
58 	STEP_DECRYPT,
59 };
60 
61 struct bio_post_read_ctx {
62 	struct bio *bio;
63 	struct work_struct work;
64 	unsigned int cur_step;
65 	unsigned int enabled_steps;
66 };
67 
68 static void __read_end_io(struct bio *bio)
69 {
70 	struct page *page;
71 	struct bio_vec *bv;
72 	int i;
73 
74 	bio_for_each_segment_all(bv, bio, i) {
75 		page = bv->bv_page;
76 
77 		/* PG_error was set if any post_read step failed */
78 		if (bio->bi_status || PageError(page)) {
79 			ClearPageUptodate(page);
80 			/* will re-read again later */
81 			ClearPageError(page);
82 		} else {
83 			SetPageUptodate(page);
84 		}
85 		unlock_page(page);
86 	}
87 	if (bio->bi_private)
88 		mempool_free(bio->bi_private, bio_post_read_ctx_pool);
89 	bio_put(bio);
90 }
91 
92 static void bio_post_read_processing(struct bio_post_read_ctx *ctx);
93 
94 static void decrypt_work(struct work_struct *work)
95 {
96 	struct bio_post_read_ctx *ctx =
97 		container_of(work, struct bio_post_read_ctx, work);
98 
99 	fscrypt_decrypt_bio(ctx->bio);
100 
101 	bio_post_read_processing(ctx);
102 }
103 
104 static void bio_post_read_processing(struct bio_post_read_ctx *ctx)
105 {
106 	switch (++ctx->cur_step) {
107 	case STEP_DECRYPT:
108 		if (ctx->enabled_steps & (1 << STEP_DECRYPT)) {
109 			INIT_WORK(&ctx->work, decrypt_work);
110 			fscrypt_enqueue_decrypt_work(&ctx->work);
111 			return;
112 		}
113 		ctx->cur_step++;
114 		/* fall-through */
115 	default:
116 		__read_end_io(ctx->bio);
117 	}
118 }
119 
120 static bool f2fs_bio_post_read_required(struct bio *bio)
121 {
122 	return bio->bi_private && !bio->bi_status;
123 }
124 
125 static void f2fs_read_end_io(struct bio *bio)
126 {
127 	if (time_to_inject(F2FS_P_SB(bio_first_page_all(bio)),
128 						FAULT_READ_IO)) {
129 		f2fs_show_injection_info(FAULT_READ_IO);
130 		bio->bi_status = BLK_STS_IOERR;
131 	}
132 
133 	if (f2fs_bio_post_read_required(bio)) {
134 		struct bio_post_read_ctx *ctx = bio->bi_private;
135 
136 		ctx->cur_step = STEP_INITIAL;
137 		bio_post_read_processing(ctx);
138 		return;
139 	}
140 
141 	__read_end_io(bio);
142 }
143 
144 static void f2fs_write_end_io(struct bio *bio)
145 {
146 	struct f2fs_sb_info *sbi = bio->bi_private;
147 	struct bio_vec *bvec;
148 	int i;
149 
150 	if (time_to_inject(sbi, FAULT_WRITE_IO)) {
151 		f2fs_show_injection_info(FAULT_WRITE_IO);
152 		bio->bi_status = BLK_STS_IOERR;
153 	}
154 
155 	bio_for_each_segment_all(bvec, bio, i) {
156 		struct page *page = bvec->bv_page;
157 		enum count_type type = WB_DATA_TYPE(page);
158 
159 		if (IS_DUMMY_WRITTEN_PAGE(page)) {
160 			set_page_private(page, (unsigned long)NULL);
161 			ClearPagePrivate(page);
162 			unlock_page(page);
163 			mempool_free(page, sbi->write_io_dummy);
164 
165 			if (unlikely(bio->bi_status))
166 				f2fs_stop_checkpoint(sbi, true);
167 			continue;
168 		}
169 
170 		fscrypt_pullback_bio_page(&page, true);
171 
172 		if (unlikely(bio->bi_status)) {
173 			mapping_set_error(page->mapping, -EIO);
174 			if (type == F2FS_WB_CP_DATA)
175 				f2fs_stop_checkpoint(sbi, true);
176 		}
177 
178 		f2fs_bug_on(sbi, page->mapping == NODE_MAPPING(sbi) &&
179 					page->index != nid_of_node(page));
180 
181 		dec_page_count(sbi, type);
182 		if (f2fs_in_warm_node_list(sbi, page))
183 			f2fs_del_fsync_node_entry(sbi, page);
184 		clear_cold_data(page);
185 		end_page_writeback(page);
186 	}
187 	if (!get_pages(sbi, F2FS_WB_CP_DATA) &&
188 				wq_has_sleeper(&sbi->cp_wait))
189 		wake_up(&sbi->cp_wait);
190 
191 	bio_put(bio);
192 }
193 
194 /*
195  * Return true, if pre_bio's bdev is same as its target device.
196  */
197 struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
198 				block_t blk_addr, struct bio *bio)
199 {
200 	struct block_device *bdev = sbi->sb->s_bdev;
201 	int i;
202 
203 	for (i = 0; i < sbi->s_ndevs; i++) {
204 		if (FDEV(i).start_blk <= blk_addr &&
205 					FDEV(i).end_blk >= blk_addr) {
206 			blk_addr -= FDEV(i).start_blk;
207 			bdev = FDEV(i).bdev;
208 			break;
209 		}
210 	}
211 	if (bio) {
212 		bio_set_dev(bio, bdev);
213 		bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
214 	}
215 	return bdev;
216 }
217 
218 int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr)
219 {
220 	int i;
221 
222 	for (i = 0; i < sbi->s_ndevs; i++)
223 		if (FDEV(i).start_blk <= blkaddr && FDEV(i).end_blk >= blkaddr)
224 			return i;
225 	return 0;
226 }
227 
228 static bool __same_bdev(struct f2fs_sb_info *sbi,
229 				block_t blk_addr, struct bio *bio)
230 {
231 	struct block_device *b = f2fs_target_device(sbi, blk_addr, NULL);
232 	return bio->bi_disk == b->bd_disk && bio->bi_partno == b->bd_partno;
233 }
234 
235 /*
236  * Low-level block read/write IO operations.
237  */
238 static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
239 				struct writeback_control *wbc,
240 				int npages, bool is_read,
241 				enum page_type type, enum temp_type temp)
242 {
243 	struct bio *bio;
244 
245 	bio = f2fs_bio_alloc(sbi, npages, true);
246 
247 	f2fs_target_device(sbi, blk_addr, bio);
248 	if (is_read) {
249 		bio->bi_end_io = f2fs_read_end_io;
250 		bio->bi_private = NULL;
251 	} else {
252 		bio->bi_end_io = f2fs_write_end_io;
253 		bio->bi_private = sbi;
254 		bio->bi_write_hint = f2fs_io_type_to_rw_hint(sbi, type, temp);
255 	}
256 	if (wbc)
257 		wbc_init_bio(wbc, bio);
258 
259 	return bio;
260 }
261 
262 static inline void __submit_bio(struct f2fs_sb_info *sbi,
263 				struct bio *bio, enum page_type type)
264 {
265 	if (!is_read_io(bio_op(bio))) {
266 		unsigned int start;
267 
268 		if (type != DATA && type != NODE)
269 			goto submit_io;
270 
271 		if (test_opt(sbi, LFS) && current->plug)
272 			blk_finish_plug(current->plug);
273 
274 		start = bio->bi_iter.bi_size >> F2FS_BLKSIZE_BITS;
275 		start %= F2FS_IO_SIZE(sbi);
276 
277 		if (start == 0)
278 			goto submit_io;
279 
280 		/* fill dummy pages */
281 		for (; start < F2FS_IO_SIZE(sbi); start++) {
282 			struct page *page =
283 				mempool_alloc(sbi->write_io_dummy,
284 					GFP_NOIO | __GFP_ZERO | __GFP_NOFAIL);
285 			f2fs_bug_on(sbi, !page);
286 
287 			SetPagePrivate(page);
288 			set_page_private(page, (unsigned long)DUMMY_WRITTEN_PAGE);
289 			lock_page(page);
290 			if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE)
291 				f2fs_bug_on(sbi, 1);
292 		}
293 		/*
294 		 * In the NODE case, we lose next block address chain. So, we
295 		 * need to do checkpoint in f2fs_sync_file.
296 		 */
297 		if (type == NODE)
298 			set_sbi_flag(sbi, SBI_NEED_CP);
299 	}
300 submit_io:
301 	if (is_read_io(bio_op(bio)))
302 		trace_f2fs_submit_read_bio(sbi->sb, type, bio);
303 	else
304 		trace_f2fs_submit_write_bio(sbi->sb, type, bio);
305 	submit_bio(bio);
306 }
307 
308 static void __submit_merged_bio(struct f2fs_bio_info *io)
309 {
310 	struct f2fs_io_info *fio = &io->fio;
311 
312 	if (!io->bio)
313 		return;
314 
315 	bio_set_op_attrs(io->bio, fio->op, fio->op_flags);
316 
317 	if (is_read_io(fio->op))
318 		trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
319 	else
320 		trace_f2fs_prepare_write_bio(io->sbi->sb, fio->type, io->bio);
321 
322 	__submit_bio(io->sbi, io->bio, fio->type);
323 	io->bio = NULL;
324 }
325 
326 static bool __has_merged_page(struct f2fs_bio_info *io, struct inode *inode,
327 						struct page *page, nid_t ino)
328 {
329 	struct bio_vec *bvec;
330 	struct page *target;
331 	int i;
332 
333 	if (!io->bio)
334 		return false;
335 
336 	if (!inode && !page && !ino)
337 		return true;
338 
339 	bio_for_each_segment_all(bvec, io->bio, i) {
340 
341 		if (bvec->bv_page->mapping)
342 			target = bvec->bv_page;
343 		else
344 			target = fscrypt_control_page(bvec->bv_page);
345 
346 		if (inode && inode == target->mapping->host)
347 			return true;
348 		if (page && page == target)
349 			return true;
350 		if (ino && ino == ino_of_node(target))
351 			return true;
352 	}
353 
354 	return false;
355 }
356 
357 static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
358 						struct page *page, nid_t ino,
359 						enum page_type type)
360 {
361 	enum page_type btype = PAGE_TYPE_OF_BIO(type);
362 	enum temp_type temp;
363 	struct f2fs_bio_info *io;
364 	bool ret = false;
365 
366 	for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
367 		io = sbi->write_io[btype] + temp;
368 
369 		down_read(&io->io_rwsem);
370 		ret = __has_merged_page(io, inode, page, ino);
371 		up_read(&io->io_rwsem);
372 
373 		/* TODO: use HOT temp only for meta pages now. */
374 		if (ret || btype == META)
375 			break;
376 	}
377 	return ret;
378 }
379 
380 static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
381 				enum page_type type, enum temp_type temp)
382 {
383 	enum page_type btype = PAGE_TYPE_OF_BIO(type);
384 	struct f2fs_bio_info *io = sbi->write_io[btype] + temp;
385 
386 	down_write(&io->io_rwsem);
387 
388 	/* change META to META_FLUSH in the checkpoint procedure */
389 	if (type >= META_FLUSH) {
390 		io->fio.type = META_FLUSH;
391 		io->fio.op = REQ_OP_WRITE;
392 		io->fio.op_flags = REQ_META | REQ_PRIO | REQ_SYNC;
393 		if (!test_opt(sbi, NOBARRIER))
394 			io->fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
395 	}
396 	__submit_merged_bio(io);
397 	up_write(&io->io_rwsem);
398 }
399 
400 static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
401 				struct inode *inode, struct page *page,
402 				nid_t ino, enum page_type type, bool force)
403 {
404 	enum temp_type temp;
405 
406 	if (!force && !has_merged_page(sbi, inode, page, ino, type))
407 		return;
408 
409 	for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
410 
411 		__f2fs_submit_merged_write(sbi, type, temp);
412 
413 		/* TODO: use HOT temp only for meta pages now. */
414 		if (type >= META)
415 			break;
416 	}
417 }
418 
419 void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
420 {
421 	__submit_merged_write_cond(sbi, NULL, 0, 0, type, true);
422 }
423 
424 void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
425 				struct inode *inode, struct page *page,
426 				nid_t ino, enum page_type type)
427 {
428 	__submit_merged_write_cond(sbi, inode, page, ino, type, false);
429 }
430 
431 void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
432 {
433 	f2fs_submit_merged_write(sbi, DATA);
434 	f2fs_submit_merged_write(sbi, NODE);
435 	f2fs_submit_merged_write(sbi, META);
436 }
437 
438 /*
439  * Fill the locked page with data located in the block address.
440  * A caller needs to unlock the page on failure.
441  */
442 int f2fs_submit_page_bio(struct f2fs_io_info *fio)
443 {
444 	struct bio *bio;
445 	struct page *page = fio->encrypted_page ?
446 			fio->encrypted_page : fio->page;
447 
448 	if (!f2fs_is_valid_blkaddr(fio->sbi, fio->new_blkaddr,
449 			__is_meta_io(fio) ? META_GENERIC : DATA_GENERIC))
450 		return -EFAULT;
451 
452 	trace_f2fs_submit_page_bio(page, fio);
453 	f2fs_trace_ios(fio, 0);
454 
455 	/* Allocate a new bio */
456 	bio = __bio_alloc(fio->sbi, fio->new_blkaddr, fio->io_wbc,
457 				1, is_read_io(fio->op), fio->type, fio->temp);
458 
459 	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
460 		bio_put(bio);
461 		return -EFAULT;
462 	}
463 	bio_set_op_attrs(bio, fio->op, fio->op_flags);
464 
465 	__submit_bio(fio->sbi, bio, fio->type);
466 
467 	if (!is_read_io(fio->op))
468 		inc_page_count(fio->sbi, WB_DATA_TYPE(fio->page));
469 	return 0;
470 }
471 
472 void f2fs_submit_page_write(struct f2fs_io_info *fio)
473 {
474 	struct f2fs_sb_info *sbi = fio->sbi;
475 	enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
476 	struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
477 	struct page *bio_page;
478 
479 	f2fs_bug_on(sbi, is_read_io(fio->op));
480 
481 	down_write(&io->io_rwsem);
482 next:
483 	if (fio->in_list) {
484 		spin_lock(&io->io_lock);
485 		if (list_empty(&io->io_list)) {
486 			spin_unlock(&io->io_lock);
487 			goto out;
488 		}
489 		fio = list_first_entry(&io->io_list,
490 						struct f2fs_io_info, list);
491 		list_del(&fio->list);
492 		spin_unlock(&io->io_lock);
493 	}
494 
495 	if (__is_valid_data_blkaddr(fio->old_blkaddr))
496 		verify_block_addr(fio, fio->old_blkaddr);
497 	verify_block_addr(fio, fio->new_blkaddr);
498 
499 	bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
500 
501 	/* set submitted = true as a return value */
502 	fio->submitted = true;
503 
504 	inc_page_count(sbi, WB_DATA_TYPE(bio_page));
505 
506 	if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
507 	    (io->fio.op != fio->op || io->fio.op_flags != fio->op_flags) ||
508 			!__same_bdev(sbi, fio->new_blkaddr, io->bio)))
509 		__submit_merged_bio(io);
510 alloc_new:
511 	if (io->bio == NULL) {
512 		if ((fio->type == DATA || fio->type == NODE) &&
513 				fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
514 			dec_page_count(sbi, WB_DATA_TYPE(bio_page));
515 			fio->retry = true;
516 			goto skip;
517 		}
518 		io->bio = __bio_alloc(sbi, fio->new_blkaddr, fio->io_wbc,
519 						BIO_MAX_PAGES, false,
520 						fio->type, fio->temp);
521 		io->fio = *fio;
522 	}
523 
524 	if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) < PAGE_SIZE) {
525 		__submit_merged_bio(io);
526 		goto alloc_new;
527 	}
528 
529 	if (fio->io_wbc)
530 		wbc_account_io(fio->io_wbc, bio_page, PAGE_SIZE);
531 
532 	io->last_block_in_bio = fio->new_blkaddr;
533 	f2fs_trace_ios(fio, 0);
534 
535 	trace_f2fs_submit_page_write(fio->page, fio);
536 skip:
537 	if (fio->in_list)
538 		goto next;
539 out:
540 	if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) ||
541 				f2fs_is_checkpoint_ready(sbi))
542 		__submit_merged_bio(io);
543 	up_write(&io->io_rwsem);
544 }
545 
546 static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
547 					unsigned nr_pages, unsigned op_flag)
548 {
549 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
550 	struct bio *bio;
551 	struct bio_post_read_ctx *ctx;
552 	unsigned int post_read_steps = 0;
553 
554 	if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC))
555 		return ERR_PTR(-EFAULT);
556 
557 	bio = f2fs_bio_alloc(sbi, min_t(int, nr_pages, BIO_MAX_PAGES), false);
558 	if (!bio)
559 		return ERR_PTR(-ENOMEM);
560 	f2fs_target_device(sbi, blkaddr, bio);
561 	bio->bi_end_io = f2fs_read_end_io;
562 	bio_set_op_attrs(bio, REQ_OP_READ, op_flag);
563 
564 	if (f2fs_encrypted_file(inode))
565 		post_read_steps |= 1 << STEP_DECRYPT;
566 	if (post_read_steps) {
567 		ctx = mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS);
568 		if (!ctx) {
569 			bio_put(bio);
570 			return ERR_PTR(-ENOMEM);
571 		}
572 		ctx->bio = bio;
573 		ctx->enabled_steps = post_read_steps;
574 		bio->bi_private = ctx;
575 	}
576 
577 	return bio;
578 }
579 
580 /* This can handle encryption stuffs */
581 static int f2fs_submit_page_read(struct inode *inode, struct page *page,
582 							block_t blkaddr)
583 {
584 	struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1, 0);
585 
586 	if (IS_ERR(bio))
587 		return PTR_ERR(bio);
588 
589 	/* wait for GCed page writeback via META_MAPPING */
590 	f2fs_wait_on_block_writeback(inode, blkaddr);
591 
592 	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
593 		bio_put(bio);
594 		return -EFAULT;
595 	}
596 	ClearPageError(page);
597 	__submit_bio(F2FS_I_SB(inode), bio, DATA);
598 	return 0;
599 }
600 
601 static void __set_data_blkaddr(struct dnode_of_data *dn)
602 {
603 	struct f2fs_node *rn = F2FS_NODE(dn->node_page);
604 	__le32 *addr_array;
605 	int base = 0;
606 
607 	if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))
608 		base = get_extra_isize(dn->inode);
609 
610 	/* Get physical address of data block */
611 	addr_array = blkaddr_in_node(rn);
612 	addr_array[base + dn->ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
613 }
614 
615 /*
616  * Lock ordering for the change of data block address:
617  * ->data_page
618  *  ->node_page
619  *    update block addresses in the node page
620  */
621 void f2fs_set_data_blkaddr(struct dnode_of_data *dn)
622 {
623 	f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
624 	__set_data_blkaddr(dn);
625 	if (set_page_dirty(dn->node_page))
626 		dn->node_changed = true;
627 }
628 
629 void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
630 {
631 	dn->data_blkaddr = blkaddr;
632 	f2fs_set_data_blkaddr(dn);
633 	f2fs_update_extent_cache(dn);
634 }
635 
636 /* dn->ofs_in_node will be returned with up-to-date last block pointer */
637 int f2fs_reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)
638 {
639 	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
640 	int err;
641 
642 	if (!count)
643 		return 0;
644 
645 	if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
646 		return -EPERM;
647 	if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
648 		return err;
649 
650 	trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
651 						dn->ofs_in_node, count);
652 
653 	f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
654 
655 	for (; count > 0; dn->ofs_in_node++) {
656 		block_t blkaddr = datablock_addr(dn->inode,
657 					dn->node_page, dn->ofs_in_node);
658 		if (blkaddr == NULL_ADDR) {
659 			dn->data_blkaddr = NEW_ADDR;
660 			__set_data_blkaddr(dn);
661 			count--;
662 		}
663 	}
664 
665 	if (set_page_dirty(dn->node_page))
666 		dn->node_changed = true;
667 	return 0;
668 }
669 
670 /* Should keep dn->ofs_in_node unchanged */
671 int f2fs_reserve_new_block(struct dnode_of_data *dn)
672 {
673 	unsigned int ofs_in_node = dn->ofs_in_node;
674 	int ret;
675 
676 	ret = f2fs_reserve_new_blocks(dn, 1);
677 	dn->ofs_in_node = ofs_in_node;
678 	return ret;
679 }
680 
681 int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
682 {
683 	bool need_put = dn->inode_page ? false : true;
684 	int err;
685 
686 	err = f2fs_get_dnode_of_data(dn, index, ALLOC_NODE);
687 	if (err)
688 		return err;
689 
690 	if (dn->data_blkaddr == NULL_ADDR)
691 		err = f2fs_reserve_new_block(dn);
692 	if (err || need_put)
693 		f2fs_put_dnode(dn);
694 	return err;
695 }
696 
697 int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
698 {
699 	struct extent_info ei  = {0,0,0};
700 	struct inode *inode = dn->inode;
701 
702 	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
703 		dn->data_blkaddr = ei.blk + index - ei.fofs;
704 		return 0;
705 	}
706 
707 	return f2fs_reserve_block(dn, index);
708 }
709 
710 struct page *f2fs_get_read_data_page(struct inode *inode, pgoff_t index,
711 						int op_flags, bool for_write)
712 {
713 	struct address_space *mapping = inode->i_mapping;
714 	struct dnode_of_data dn;
715 	struct page *page;
716 	struct extent_info ei = {0,0,0};
717 	int err;
718 
719 	page = f2fs_grab_cache_page(mapping, index, for_write);
720 	if (!page)
721 		return ERR_PTR(-ENOMEM);
722 
723 	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
724 		dn.data_blkaddr = ei.blk + index - ei.fofs;
725 		goto got_it;
726 	}
727 
728 	set_new_dnode(&dn, inode, NULL, NULL, 0);
729 	err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
730 	if (err)
731 		goto put_err;
732 	f2fs_put_dnode(&dn);
733 
734 	if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
735 		err = -ENOENT;
736 		goto put_err;
737 	}
738 got_it:
739 	if (PageUptodate(page)) {
740 		unlock_page(page);
741 		return page;
742 	}
743 
744 	/*
745 	 * A new dentry page is allocated but not able to be written, since its
746 	 * new inode page couldn't be allocated due to -ENOSPC.
747 	 * In such the case, its blkaddr can be remained as NEW_ADDR.
748 	 * see, f2fs_add_link -> f2fs_get_new_data_page ->
749 	 * f2fs_init_inode_metadata.
750 	 */
751 	if (dn.data_blkaddr == NEW_ADDR) {
752 		zero_user_segment(page, 0, PAGE_SIZE);
753 		if (!PageUptodate(page))
754 			SetPageUptodate(page);
755 		unlock_page(page);
756 		return page;
757 	}
758 
759 	err = f2fs_submit_page_read(inode, page, dn.data_blkaddr);
760 	if (err)
761 		goto put_err;
762 	return page;
763 
764 put_err:
765 	f2fs_put_page(page, 1);
766 	return ERR_PTR(err);
767 }
768 
769 struct page *f2fs_find_data_page(struct inode *inode, pgoff_t index)
770 {
771 	struct address_space *mapping = inode->i_mapping;
772 	struct page *page;
773 
774 	page = find_get_page(mapping, index);
775 	if (page && PageUptodate(page))
776 		return page;
777 	f2fs_put_page(page, 0);
778 
779 	page = f2fs_get_read_data_page(inode, index, 0, false);
780 	if (IS_ERR(page))
781 		return page;
782 
783 	if (PageUptodate(page))
784 		return page;
785 
786 	wait_on_page_locked(page);
787 	if (unlikely(!PageUptodate(page))) {
788 		f2fs_put_page(page, 0);
789 		return ERR_PTR(-EIO);
790 	}
791 	return page;
792 }
793 
794 /*
795  * If it tries to access a hole, return an error.
796  * Because, the callers, functions in dir.c and GC, should be able to know
797  * whether this page exists or not.
798  */
799 struct page *f2fs_get_lock_data_page(struct inode *inode, pgoff_t index,
800 							bool for_write)
801 {
802 	struct address_space *mapping = inode->i_mapping;
803 	struct page *page;
804 repeat:
805 	page = f2fs_get_read_data_page(inode, index, 0, for_write);
806 	if (IS_ERR(page))
807 		return page;
808 
809 	/* wait for read completion */
810 	lock_page(page);
811 	if (unlikely(page->mapping != mapping)) {
812 		f2fs_put_page(page, 1);
813 		goto repeat;
814 	}
815 	if (unlikely(!PageUptodate(page))) {
816 		f2fs_put_page(page, 1);
817 		return ERR_PTR(-EIO);
818 	}
819 	return page;
820 }
821 
822 /*
823  * Caller ensures that this data page is never allocated.
824  * A new zero-filled data page is allocated in the page cache.
825  *
826  * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
827  * f2fs_unlock_op().
828  * Note that, ipage is set only by make_empty_dir, and if any error occur,
829  * ipage should be released by this function.
830  */
831 struct page *f2fs_get_new_data_page(struct inode *inode,
832 		struct page *ipage, pgoff_t index, bool new_i_size)
833 {
834 	struct address_space *mapping = inode->i_mapping;
835 	struct page *page;
836 	struct dnode_of_data dn;
837 	int err;
838 
839 	page = f2fs_grab_cache_page(mapping, index, true);
840 	if (!page) {
841 		/*
842 		 * before exiting, we should make sure ipage will be released
843 		 * if any error occur.
844 		 */
845 		f2fs_put_page(ipage, 1);
846 		return ERR_PTR(-ENOMEM);
847 	}
848 
849 	set_new_dnode(&dn, inode, ipage, NULL, 0);
850 	err = f2fs_reserve_block(&dn, index);
851 	if (err) {
852 		f2fs_put_page(page, 1);
853 		return ERR_PTR(err);
854 	}
855 	if (!ipage)
856 		f2fs_put_dnode(&dn);
857 
858 	if (PageUptodate(page))
859 		goto got_it;
860 
861 	if (dn.data_blkaddr == NEW_ADDR) {
862 		zero_user_segment(page, 0, PAGE_SIZE);
863 		if (!PageUptodate(page))
864 			SetPageUptodate(page);
865 	} else {
866 		f2fs_put_page(page, 1);
867 
868 		/* if ipage exists, blkaddr should be NEW_ADDR */
869 		f2fs_bug_on(F2FS_I_SB(inode), ipage);
870 		page = f2fs_get_lock_data_page(inode, index, true);
871 		if (IS_ERR(page))
872 			return page;
873 	}
874 got_it:
875 	if (new_i_size && i_size_read(inode) <
876 				((loff_t)(index + 1) << PAGE_SHIFT))
877 		f2fs_i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
878 	return page;
879 }
880 
881 static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
882 {
883 	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
884 	struct f2fs_summary sum;
885 	struct node_info ni;
886 	block_t old_blkaddr;
887 	blkcnt_t count = 1;
888 	int err;
889 
890 	if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
891 		return -EPERM;
892 
893 	err = f2fs_get_node_info(sbi, dn->nid, &ni);
894 	if (err)
895 		return err;
896 
897 	dn->data_blkaddr = datablock_addr(dn->inode,
898 				dn->node_page, dn->ofs_in_node);
899 	if (dn->data_blkaddr != NULL_ADDR)
900 		goto alloc;
901 
902 	if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
903 		return err;
904 
905 alloc:
906 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
907 	old_blkaddr = dn->data_blkaddr;
908 	f2fs_allocate_data_block(sbi, NULL, old_blkaddr, &dn->data_blkaddr,
909 					&sum, seg_type, NULL, false);
910 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
911 		invalidate_mapping_pages(META_MAPPING(sbi),
912 					old_blkaddr, old_blkaddr);
913 	f2fs_set_data_blkaddr(dn);
914 
915 	/*
916 	 * i_size will be updated by direct_IO. Otherwise, we'll get stale
917 	 * data from unwritten block via dio_read.
918 	 */
919 	return 0;
920 }
921 
922 int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
923 {
924 	struct inode *inode = file_inode(iocb->ki_filp);
925 	struct f2fs_map_blocks map;
926 	int flag;
927 	int err = 0;
928 	bool direct_io = iocb->ki_flags & IOCB_DIRECT;
929 
930 	/* convert inline data for Direct I/O*/
931 	if (direct_io) {
932 		err = f2fs_convert_inline_inode(inode);
933 		if (err)
934 			return err;
935 	}
936 
937 	if (is_inode_flag_set(inode, FI_NO_PREALLOC))
938 		return 0;
939 
940 	map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
941 	map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
942 	if (map.m_len > map.m_lblk)
943 		map.m_len -= map.m_lblk;
944 	else
945 		map.m_len = 0;
946 
947 	map.m_next_pgofs = NULL;
948 	map.m_next_extent = NULL;
949 	map.m_seg_type = NO_CHECK_TYPE;
950 
951 	if (direct_io) {
952 		map.m_seg_type = f2fs_rw_hint_to_seg_type(iocb->ki_hint);
953 		flag = f2fs_force_buffered_io(inode, iocb, from) ?
954 					F2FS_GET_BLOCK_PRE_AIO :
955 					F2FS_GET_BLOCK_PRE_DIO;
956 		goto map_blocks;
957 	}
958 	if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA(inode)) {
959 		err = f2fs_convert_inline_inode(inode);
960 		if (err)
961 			return err;
962 	}
963 	if (f2fs_has_inline_data(inode))
964 		return err;
965 
966 	flag = F2FS_GET_BLOCK_PRE_AIO;
967 
968 map_blocks:
969 	err = f2fs_map_blocks(inode, &map, 1, flag);
970 	if (map.m_len > 0 && err == -ENOSPC) {
971 		if (!direct_io)
972 			set_inode_flag(inode, FI_NO_PREALLOC);
973 		err = 0;
974 	}
975 	return err;
976 }
977 
978 void __do_map_lock(struct f2fs_sb_info *sbi, int flag, bool lock)
979 {
980 	if (flag == F2FS_GET_BLOCK_PRE_AIO) {
981 		if (lock)
982 			down_read(&sbi->node_change);
983 		else
984 			up_read(&sbi->node_change);
985 	} else {
986 		if (lock)
987 			f2fs_lock_op(sbi);
988 		else
989 			f2fs_unlock_op(sbi);
990 	}
991 }
992 
993 /*
994  * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
995  * f2fs_map_blocks structure.
996  * If original data blocks are allocated, then give them to blockdev.
997  * Otherwise,
998  *     a. preallocate requested block addresses
999  *     b. do not use extent cache for better performance
1000  *     c. give the block addresses to blockdev
1001  */
1002 int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
1003 						int create, int flag)
1004 {
1005 	unsigned int maxblocks = map->m_len;
1006 	struct dnode_of_data dn;
1007 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1008 	int mode = create ? ALLOC_NODE : LOOKUP_NODE;
1009 	pgoff_t pgofs, end_offset, end;
1010 	int err = 0, ofs = 1;
1011 	unsigned int ofs_in_node, last_ofs_in_node;
1012 	blkcnt_t prealloc;
1013 	struct extent_info ei = {0,0,0};
1014 	block_t blkaddr;
1015 	unsigned int start_pgofs;
1016 
1017 	if (!maxblocks)
1018 		return 0;
1019 
1020 	map->m_len = 0;
1021 	map->m_flags = 0;
1022 
1023 	/* it only supports block size == page size */
1024 	pgofs =	(pgoff_t)map->m_lblk;
1025 	end = pgofs + maxblocks;
1026 
1027 	if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
1028 		map->m_pblk = ei.blk + pgofs - ei.fofs;
1029 		map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
1030 		map->m_flags = F2FS_MAP_MAPPED;
1031 		if (map->m_next_extent)
1032 			*map->m_next_extent = pgofs + map->m_len;
1033 		goto out;
1034 	}
1035 
1036 next_dnode:
1037 	if (create)
1038 		__do_map_lock(sbi, flag, true);
1039 
1040 	/* When reading holes, we need its node page */
1041 	set_new_dnode(&dn, inode, NULL, NULL, 0);
1042 	err = f2fs_get_dnode_of_data(&dn, pgofs, mode);
1043 	if (err) {
1044 		if (flag == F2FS_GET_BLOCK_BMAP)
1045 			map->m_pblk = 0;
1046 		if (err == -ENOENT) {
1047 			err = 0;
1048 			if (map->m_next_pgofs)
1049 				*map->m_next_pgofs =
1050 					f2fs_get_next_page_offset(&dn, pgofs);
1051 			if (map->m_next_extent)
1052 				*map->m_next_extent =
1053 					f2fs_get_next_page_offset(&dn, pgofs);
1054 		}
1055 		goto unlock_out;
1056 	}
1057 
1058 	start_pgofs = pgofs;
1059 	prealloc = 0;
1060 	last_ofs_in_node = ofs_in_node = dn.ofs_in_node;
1061 	end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
1062 
1063 next_block:
1064 	blkaddr = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node);
1065 
1066 	if (__is_valid_data_blkaddr(blkaddr) &&
1067 		!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC)) {
1068 		err = -EFAULT;
1069 		goto sync_out;
1070 	}
1071 
1072 	if (is_valid_data_blkaddr(sbi, blkaddr)) {
1073 		/* use out-place-update for driect IO under LFS mode */
1074 		if (test_opt(sbi, LFS) && create &&
1075 				flag == F2FS_GET_BLOCK_DIO) {
1076 			err = __allocate_data_block(&dn, map->m_seg_type);
1077 			if (!err)
1078 				set_inode_flag(inode, FI_APPEND_WRITE);
1079 		}
1080 	} else {
1081 		if (create) {
1082 			if (unlikely(f2fs_cp_error(sbi))) {
1083 				err = -EIO;
1084 				goto sync_out;
1085 			}
1086 			if (flag == F2FS_GET_BLOCK_PRE_AIO) {
1087 				if (blkaddr == NULL_ADDR) {
1088 					prealloc++;
1089 					last_ofs_in_node = dn.ofs_in_node;
1090 				}
1091 			} else {
1092 				WARN_ON(flag != F2FS_GET_BLOCK_PRE_DIO &&
1093 					flag != F2FS_GET_BLOCK_DIO);
1094 				err = __allocate_data_block(&dn,
1095 							map->m_seg_type);
1096 				if (!err)
1097 					set_inode_flag(inode, FI_APPEND_WRITE);
1098 			}
1099 			if (err)
1100 				goto sync_out;
1101 			map->m_flags |= F2FS_MAP_NEW;
1102 			blkaddr = dn.data_blkaddr;
1103 		} else {
1104 			if (flag == F2FS_GET_BLOCK_BMAP) {
1105 				map->m_pblk = 0;
1106 				goto sync_out;
1107 			}
1108 			if (flag == F2FS_GET_BLOCK_PRECACHE)
1109 				goto sync_out;
1110 			if (flag == F2FS_GET_BLOCK_FIEMAP &&
1111 						blkaddr == NULL_ADDR) {
1112 				if (map->m_next_pgofs)
1113 					*map->m_next_pgofs = pgofs + 1;
1114 				goto sync_out;
1115 			}
1116 			if (flag != F2FS_GET_BLOCK_FIEMAP) {
1117 				/* for defragment case */
1118 				if (map->m_next_pgofs)
1119 					*map->m_next_pgofs = pgofs + 1;
1120 				goto sync_out;
1121 			}
1122 		}
1123 	}
1124 
1125 	if (flag == F2FS_GET_BLOCK_PRE_AIO)
1126 		goto skip;
1127 
1128 	if (map->m_len == 0) {
1129 		/* preallocated unwritten block should be mapped for fiemap. */
1130 		if (blkaddr == NEW_ADDR)
1131 			map->m_flags |= F2FS_MAP_UNWRITTEN;
1132 		map->m_flags |= F2FS_MAP_MAPPED;
1133 
1134 		map->m_pblk = blkaddr;
1135 		map->m_len = 1;
1136 	} else if ((map->m_pblk != NEW_ADDR &&
1137 			blkaddr == (map->m_pblk + ofs)) ||
1138 			(map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
1139 			flag == F2FS_GET_BLOCK_PRE_DIO) {
1140 		ofs++;
1141 		map->m_len++;
1142 	} else {
1143 		goto sync_out;
1144 	}
1145 
1146 skip:
1147 	dn.ofs_in_node++;
1148 	pgofs++;
1149 
1150 	/* preallocate blocks in batch for one dnode page */
1151 	if (flag == F2FS_GET_BLOCK_PRE_AIO &&
1152 			(pgofs == end || dn.ofs_in_node == end_offset)) {
1153 
1154 		dn.ofs_in_node = ofs_in_node;
1155 		err = f2fs_reserve_new_blocks(&dn, prealloc);
1156 		if (err)
1157 			goto sync_out;
1158 
1159 		map->m_len += dn.ofs_in_node - ofs_in_node;
1160 		if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
1161 			err = -ENOSPC;
1162 			goto sync_out;
1163 		}
1164 		dn.ofs_in_node = end_offset;
1165 	}
1166 
1167 	if (pgofs >= end)
1168 		goto sync_out;
1169 	else if (dn.ofs_in_node < end_offset)
1170 		goto next_block;
1171 
1172 	if (flag == F2FS_GET_BLOCK_PRECACHE) {
1173 		if (map->m_flags & F2FS_MAP_MAPPED) {
1174 			unsigned int ofs = start_pgofs - map->m_lblk;
1175 
1176 			f2fs_update_extent_cache_range(&dn,
1177 				start_pgofs, map->m_pblk + ofs,
1178 				map->m_len - ofs);
1179 		}
1180 	}
1181 
1182 	f2fs_put_dnode(&dn);
1183 
1184 	if (create) {
1185 		__do_map_lock(sbi, flag, false);
1186 		f2fs_balance_fs(sbi, dn.node_changed);
1187 	}
1188 	goto next_dnode;
1189 
1190 sync_out:
1191 	if (flag == F2FS_GET_BLOCK_PRECACHE) {
1192 		if (map->m_flags & F2FS_MAP_MAPPED) {
1193 			unsigned int ofs = start_pgofs - map->m_lblk;
1194 
1195 			f2fs_update_extent_cache_range(&dn,
1196 				start_pgofs, map->m_pblk + ofs,
1197 				map->m_len - ofs);
1198 		}
1199 		if (map->m_next_extent)
1200 			*map->m_next_extent = pgofs + 1;
1201 	}
1202 	f2fs_put_dnode(&dn);
1203 unlock_out:
1204 	if (create) {
1205 		__do_map_lock(sbi, flag, false);
1206 		f2fs_balance_fs(sbi, dn.node_changed);
1207 	}
1208 out:
1209 	trace_f2fs_map_blocks(inode, map, err);
1210 	return err;
1211 }
1212 
1213 bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len)
1214 {
1215 	struct f2fs_map_blocks map;
1216 	block_t last_lblk;
1217 	int err;
1218 
1219 	if (pos + len > i_size_read(inode))
1220 		return false;
1221 
1222 	map.m_lblk = F2FS_BYTES_TO_BLK(pos);
1223 	map.m_next_pgofs = NULL;
1224 	map.m_next_extent = NULL;
1225 	map.m_seg_type = NO_CHECK_TYPE;
1226 	last_lblk = F2FS_BLK_ALIGN(pos + len);
1227 
1228 	while (map.m_lblk < last_lblk) {
1229 		map.m_len = last_lblk - map.m_lblk;
1230 		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT);
1231 		if (err || map.m_len == 0)
1232 			return false;
1233 		map.m_lblk += map.m_len;
1234 	}
1235 	return true;
1236 }
1237 
1238 static int __get_data_block(struct inode *inode, sector_t iblock,
1239 			struct buffer_head *bh, int create, int flag,
1240 			pgoff_t *next_pgofs, int seg_type)
1241 {
1242 	struct f2fs_map_blocks map;
1243 	int err;
1244 
1245 	map.m_lblk = iblock;
1246 	map.m_len = bh->b_size >> inode->i_blkbits;
1247 	map.m_next_pgofs = next_pgofs;
1248 	map.m_next_extent = NULL;
1249 	map.m_seg_type = seg_type;
1250 
1251 	err = f2fs_map_blocks(inode, &map, create, flag);
1252 	if (!err) {
1253 		map_bh(bh, inode->i_sb, map.m_pblk);
1254 		bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
1255 		bh->b_size = (u64)map.m_len << inode->i_blkbits;
1256 	}
1257 	return err;
1258 }
1259 
1260 static int get_data_block(struct inode *inode, sector_t iblock,
1261 			struct buffer_head *bh_result, int create, int flag,
1262 			pgoff_t *next_pgofs)
1263 {
1264 	return __get_data_block(inode, iblock, bh_result, create,
1265 							flag, next_pgofs,
1266 							NO_CHECK_TYPE);
1267 }
1268 
1269 static int get_data_block_dio(struct inode *inode, sector_t iblock,
1270 			struct buffer_head *bh_result, int create)
1271 {
1272 	return __get_data_block(inode, iblock, bh_result, create,
1273 						F2FS_GET_BLOCK_DIO, NULL,
1274 						f2fs_rw_hint_to_seg_type(
1275 							inode->i_write_hint));
1276 }
1277 
1278 static int get_data_block_bmap(struct inode *inode, sector_t iblock,
1279 			struct buffer_head *bh_result, int create)
1280 {
1281 	/* Block number less than F2FS MAX BLOCKS */
1282 	if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
1283 		return -EFBIG;
1284 
1285 	return __get_data_block(inode, iblock, bh_result, create,
1286 						F2FS_GET_BLOCK_BMAP, NULL,
1287 						NO_CHECK_TYPE);
1288 }
1289 
1290 static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
1291 {
1292 	return (offset >> inode->i_blkbits);
1293 }
1294 
1295 static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
1296 {
1297 	return (blk << inode->i_blkbits);
1298 }
1299 
1300 static int f2fs_xattr_fiemap(struct inode *inode,
1301 				struct fiemap_extent_info *fieinfo)
1302 {
1303 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1304 	struct page *page;
1305 	struct node_info ni;
1306 	__u64 phys = 0, len;
1307 	__u32 flags;
1308 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
1309 	int err = 0;
1310 
1311 	if (f2fs_has_inline_xattr(inode)) {
1312 		int offset;
1313 
1314 		page = f2fs_grab_cache_page(NODE_MAPPING(sbi),
1315 						inode->i_ino, false);
1316 		if (!page)
1317 			return -ENOMEM;
1318 
1319 		err = f2fs_get_node_info(sbi, inode->i_ino, &ni);
1320 		if (err) {
1321 			f2fs_put_page(page, 1);
1322 			return err;
1323 		}
1324 
1325 		phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1326 		offset = offsetof(struct f2fs_inode, i_addr) +
1327 					sizeof(__le32) * (DEF_ADDRS_PER_INODE -
1328 					get_inline_xattr_addrs(inode));
1329 
1330 		phys += offset;
1331 		len = inline_xattr_size(inode);
1332 
1333 		f2fs_put_page(page, 1);
1334 
1335 		flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED;
1336 
1337 		if (!xnid)
1338 			flags |= FIEMAP_EXTENT_LAST;
1339 
1340 		err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1341 		if (err || err == 1)
1342 			return err;
1343 	}
1344 
1345 	if (xnid) {
1346 		page = f2fs_grab_cache_page(NODE_MAPPING(sbi), xnid, false);
1347 		if (!page)
1348 			return -ENOMEM;
1349 
1350 		err = f2fs_get_node_info(sbi, xnid, &ni);
1351 		if (err) {
1352 			f2fs_put_page(page, 1);
1353 			return err;
1354 		}
1355 
1356 		phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1357 		len = inode->i_sb->s_blocksize;
1358 
1359 		f2fs_put_page(page, 1);
1360 
1361 		flags = FIEMAP_EXTENT_LAST;
1362 	}
1363 
1364 	if (phys)
1365 		err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1366 
1367 	return (err < 0 ? err : 0);
1368 }
1369 
1370 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1371 		u64 start, u64 len)
1372 {
1373 	struct buffer_head map_bh;
1374 	sector_t start_blk, last_blk;
1375 	pgoff_t next_pgofs;
1376 	u64 logical = 0, phys = 0, size = 0;
1377 	u32 flags = 0;
1378 	int ret = 0;
1379 
1380 	if (fieinfo->fi_flags & FIEMAP_FLAG_CACHE) {
1381 		ret = f2fs_precache_extents(inode);
1382 		if (ret)
1383 			return ret;
1384 	}
1385 
1386 	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR);
1387 	if (ret)
1388 		return ret;
1389 
1390 	inode_lock(inode);
1391 
1392 	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
1393 		ret = f2fs_xattr_fiemap(inode, fieinfo);
1394 		goto out;
1395 	}
1396 
1397 	if (f2fs_has_inline_data(inode)) {
1398 		ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
1399 		if (ret != -EAGAIN)
1400 			goto out;
1401 	}
1402 
1403 	if (logical_to_blk(inode, len) == 0)
1404 		len = blk_to_logical(inode, 1);
1405 
1406 	start_blk = logical_to_blk(inode, start);
1407 	last_blk = logical_to_blk(inode, start + len - 1);
1408 
1409 next:
1410 	memset(&map_bh, 0, sizeof(struct buffer_head));
1411 	map_bh.b_size = len;
1412 
1413 	ret = get_data_block(inode, start_blk, &map_bh, 0,
1414 					F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
1415 	if (ret)
1416 		goto out;
1417 
1418 	/* HOLE */
1419 	if (!buffer_mapped(&map_bh)) {
1420 		start_blk = next_pgofs;
1421 
1422 		if (blk_to_logical(inode, start_blk) < blk_to_logical(inode,
1423 					F2FS_I_SB(inode)->max_file_blocks))
1424 			goto prep_next;
1425 
1426 		flags |= FIEMAP_EXTENT_LAST;
1427 	}
1428 
1429 	if (size) {
1430 		if (f2fs_encrypted_inode(inode))
1431 			flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
1432 
1433 		ret = fiemap_fill_next_extent(fieinfo, logical,
1434 				phys, size, flags);
1435 	}
1436 
1437 	if (start_blk > last_blk || ret)
1438 		goto out;
1439 
1440 	logical = blk_to_logical(inode, start_blk);
1441 	phys = blk_to_logical(inode, map_bh.b_blocknr);
1442 	size = map_bh.b_size;
1443 	flags = 0;
1444 	if (buffer_unwritten(&map_bh))
1445 		flags = FIEMAP_EXTENT_UNWRITTEN;
1446 
1447 	start_blk += logical_to_blk(inode, size);
1448 
1449 prep_next:
1450 	cond_resched();
1451 	if (fatal_signal_pending(current))
1452 		ret = -EINTR;
1453 	else
1454 		goto next;
1455 out:
1456 	if (ret == 1)
1457 		ret = 0;
1458 
1459 	inode_unlock(inode);
1460 	return ret;
1461 }
1462 
1463 /*
1464  * This function was originally taken from fs/mpage.c, and customized for f2fs.
1465  * Major change was from block_size == page_size in f2fs by default.
1466  *
1467  * Note that the aops->readpages() function is ONLY used for read-ahead. If
1468  * this function ever deviates from doing just read-ahead, it should either
1469  * use ->readpage() or do the necessary surgery to decouple ->readpages()
1470  * from read-ahead.
1471  */
1472 static int f2fs_mpage_readpages(struct address_space *mapping,
1473 			struct list_head *pages, struct page *page,
1474 			unsigned nr_pages, bool is_readahead)
1475 {
1476 	struct bio *bio = NULL;
1477 	sector_t last_block_in_bio = 0;
1478 	struct inode *inode = mapping->host;
1479 	const unsigned blkbits = inode->i_blkbits;
1480 	const unsigned blocksize = 1 << blkbits;
1481 	sector_t block_in_file;
1482 	sector_t last_block;
1483 	sector_t last_block_in_file;
1484 	sector_t block_nr;
1485 	struct f2fs_map_blocks map;
1486 
1487 	map.m_pblk = 0;
1488 	map.m_lblk = 0;
1489 	map.m_len = 0;
1490 	map.m_flags = 0;
1491 	map.m_next_pgofs = NULL;
1492 	map.m_next_extent = NULL;
1493 	map.m_seg_type = NO_CHECK_TYPE;
1494 
1495 	for (; nr_pages; nr_pages--) {
1496 		if (pages) {
1497 			page = list_last_entry(pages, struct page, lru);
1498 
1499 			prefetchw(&page->flags);
1500 			list_del(&page->lru);
1501 			if (add_to_page_cache_lru(page, mapping,
1502 						  page->index,
1503 						  readahead_gfp_mask(mapping)))
1504 				goto next_page;
1505 		}
1506 
1507 		block_in_file = (sector_t)page->index;
1508 		last_block = block_in_file + nr_pages;
1509 		last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
1510 								blkbits;
1511 		if (last_block > last_block_in_file)
1512 			last_block = last_block_in_file;
1513 
1514 		/*
1515 		 * Map blocks using the previous result first.
1516 		 */
1517 		if ((map.m_flags & F2FS_MAP_MAPPED) &&
1518 				block_in_file > map.m_lblk &&
1519 				block_in_file < (map.m_lblk + map.m_len))
1520 			goto got_it;
1521 
1522 		/*
1523 		 * Then do more f2fs_map_blocks() calls until we are
1524 		 * done with this page.
1525 		 */
1526 		map.m_flags = 0;
1527 
1528 		if (block_in_file < last_block) {
1529 			map.m_lblk = block_in_file;
1530 			map.m_len = last_block - block_in_file;
1531 
1532 			if (f2fs_map_blocks(inode, &map, 0,
1533 						F2FS_GET_BLOCK_DEFAULT))
1534 				goto set_error_page;
1535 		}
1536 got_it:
1537 		if ((map.m_flags & F2FS_MAP_MAPPED)) {
1538 			block_nr = map.m_pblk + block_in_file - map.m_lblk;
1539 			SetPageMappedToDisk(page);
1540 
1541 			if (!PageUptodate(page) && !cleancache_get_page(page)) {
1542 				SetPageUptodate(page);
1543 				goto confused;
1544 			}
1545 
1546 			if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), block_nr,
1547 								DATA_GENERIC))
1548 				goto set_error_page;
1549 		} else {
1550 			zero_user_segment(page, 0, PAGE_SIZE);
1551 			if (!PageUptodate(page))
1552 				SetPageUptodate(page);
1553 			unlock_page(page);
1554 			goto next_page;
1555 		}
1556 
1557 		/*
1558 		 * This page will go to BIO.  Do we need to send this
1559 		 * BIO off first?
1560 		 */
1561 		if (bio && (last_block_in_bio != block_nr - 1 ||
1562 			!__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
1563 submit_and_realloc:
1564 			__submit_bio(F2FS_I_SB(inode), bio, DATA);
1565 			bio = NULL;
1566 		}
1567 		if (bio == NULL) {
1568 			bio = f2fs_grab_read_bio(inode, block_nr, nr_pages,
1569 					is_readahead ? REQ_RAHEAD : 0);
1570 			if (IS_ERR(bio)) {
1571 				bio = NULL;
1572 				goto set_error_page;
1573 			}
1574 		}
1575 
1576 		/*
1577 		 * If the page is under writeback, we need to wait for
1578 		 * its completion to see the correct decrypted data.
1579 		 */
1580 		f2fs_wait_on_block_writeback(inode, block_nr);
1581 
1582 		if (bio_add_page(bio, page, blocksize, 0) < blocksize)
1583 			goto submit_and_realloc;
1584 
1585 		ClearPageError(page);
1586 		last_block_in_bio = block_nr;
1587 		goto next_page;
1588 set_error_page:
1589 		SetPageError(page);
1590 		zero_user_segment(page, 0, PAGE_SIZE);
1591 		unlock_page(page);
1592 		goto next_page;
1593 confused:
1594 		if (bio) {
1595 			__submit_bio(F2FS_I_SB(inode), bio, DATA);
1596 			bio = NULL;
1597 		}
1598 		unlock_page(page);
1599 next_page:
1600 		if (pages)
1601 			put_page(page);
1602 	}
1603 	BUG_ON(pages && !list_empty(pages));
1604 	if (bio)
1605 		__submit_bio(F2FS_I_SB(inode), bio, DATA);
1606 	return 0;
1607 }
1608 
1609 static int f2fs_read_data_page(struct file *file, struct page *page)
1610 {
1611 	struct inode *inode = page->mapping->host;
1612 	int ret = -EAGAIN;
1613 
1614 	trace_f2fs_readpage(page, DATA);
1615 
1616 	/* If the file has inline data, try to read it directly */
1617 	if (f2fs_has_inline_data(inode))
1618 		ret = f2fs_read_inline_data(inode, page);
1619 	if (ret == -EAGAIN)
1620 		ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1, false);
1621 	return ret;
1622 }
1623 
1624 static int f2fs_read_data_pages(struct file *file,
1625 			struct address_space *mapping,
1626 			struct list_head *pages, unsigned nr_pages)
1627 {
1628 	struct inode *inode = mapping->host;
1629 	struct page *page = list_last_entry(pages, struct page, lru);
1630 
1631 	trace_f2fs_readpages(inode, page, nr_pages);
1632 
1633 	/* If the file has inline data, skip readpages */
1634 	if (f2fs_has_inline_data(inode))
1635 		return 0;
1636 
1637 	return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages, true);
1638 }
1639 
1640 static int encrypt_one_page(struct f2fs_io_info *fio)
1641 {
1642 	struct inode *inode = fio->page->mapping->host;
1643 	struct page *mpage;
1644 	gfp_t gfp_flags = GFP_NOFS;
1645 
1646 	if (!f2fs_encrypted_file(inode))
1647 		return 0;
1648 
1649 	/* wait for GCed page writeback via META_MAPPING */
1650 	f2fs_wait_on_block_writeback(inode, fio->old_blkaddr);
1651 
1652 retry_encrypt:
1653 	fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
1654 			PAGE_SIZE, 0, fio->page->index, gfp_flags);
1655 	if (IS_ERR(fio->encrypted_page)) {
1656 		/* flush pending IOs and wait for a while in the ENOMEM case */
1657 		if (PTR_ERR(fio->encrypted_page) == -ENOMEM) {
1658 			f2fs_flush_merged_writes(fio->sbi);
1659 			congestion_wait(BLK_RW_ASYNC, HZ/50);
1660 			gfp_flags |= __GFP_NOFAIL;
1661 			goto retry_encrypt;
1662 		}
1663 		return PTR_ERR(fio->encrypted_page);
1664 	}
1665 
1666 	mpage = find_lock_page(META_MAPPING(fio->sbi), fio->old_blkaddr);
1667 	if (mpage) {
1668 		if (PageUptodate(mpage))
1669 			memcpy(page_address(mpage),
1670 				page_address(fio->encrypted_page), PAGE_SIZE);
1671 		f2fs_put_page(mpage, 1);
1672 	}
1673 	return 0;
1674 }
1675 
1676 static inline bool check_inplace_update_policy(struct inode *inode,
1677 				struct f2fs_io_info *fio)
1678 {
1679 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1680 	unsigned int policy = SM_I(sbi)->ipu_policy;
1681 
1682 	if (policy & (0x1 << F2FS_IPU_FORCE))
1683 		return true;
1684 	if (policy & (0x1 << F2FS_IPU_SSR) && f2fs_need_SSR(sbi))
1685 		return true;
1686 	if (policy & (0x1 << F2FS_IPU_UTIL) &&
1687 			utilization(sbi) > SM_I(sbi)->min_ipu_util)
1688 		return true;
1689 	if (policy & (0x1 << F2FS_IPU_SSR_UTIL) && f2fs_need_SSR(sbi) &&
1690 			utilization(sbi) > SM_I(sbi)->min_ipu_util)
1691 		return true;
1692 
1693 	/*
1694 	 * IPU for rewrite async pages
1695 	 */
1696 	if (policy & (0x1 << F2FS_IPU_ASYNC) &&
1697 			fio && fio->op == REQ_OP_WRITE &&
1698 			!(fio->op_flags & REQ_SYNC) &&
1699 			!f2fs_encrypted_inode(inode))
1700 		return true;
1701 
1702 	/* this is only set during fdatasync */
1703 	if (policy & (0x1 << F2FS_IPU_FSYNC) &&
1704 			is_inode_flag_set(inode, FI_NEED_IPU))
1705 		return true;
1706 
1707 	if (unlikely(fio && is_sbi_flag_set(sbi, SBI_CP_DISABLED) &&
1708 			!f2fs_is_checkpointed_data(sbi, fio->old_blkaddr)))
1709 		return true;
1710 
1711 	return false;
1712 }
1713 
1714 bool f2fs_should_update_inplace(struct inode *inode, struct f2fs_io_info *fio)
1715 {
1716 	if (f2fs_is_pinned_file(inode))
1717 		return true;
1718 
1719 	/* if this is cold file, we should overwrite to avoid fragmentation */
1720 	if (file_is_cold(inode))
1721 		return true;
1722 
1723 	return check_inplace_update_policy(inode, fio);
1724 }
1725 
1726 bool f2fs_should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
1727 {
1728 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1729 
1730 	if (test_opt(sbi, LFS))
1731 		return true;
1732 	if (S_ISDIR(inode->i_mode))
1733 		return true;
1734 	if (f2fs_is_atomic_file(inode))
1735 		return true;
1736 	if (fio) {
1737 		if (is_cold_data(fio->page))
1738 			return true;
1739 		if (IS_ATOMIC_WRITTEN_PAGE(fio->page))
1740 			return true;
1741 		if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED) &&
1742 			f2fs_is_checkpointed_data(sbi, fio->old_blkaddr)))
1743 			return true;
1744 	}
1745 	return false;
1746 }
1747 
1748 static inline bool need_inplace_update(struct f2fs_io_info *fio)
1749 {
1750 	struct inode *inode = fio->page->mapping->host;
1751 
1752 	if (f2fs_should_update_outplace(inode, fio))
1753 		return false;
1754 
1755 	return f2fs_should_update_inplace(inode, fio);
1756 }
1757 
1758 int f2fs_do_write_data_page(struct f2fs_io_info *fio)
1759 {
1760 	struct page *page = fio->page;
1761 	struct inode *inode = page->mapping->host;
1762 	struct dnode_of_data dn;
1763 	struct extent_info ei = {0,0,0};
1764 	struct node_info ni;
1765 	bool ipu_force = false;
1766 	int err = 0;
1767 
1768 	set_new_dnode(&dn, inode, NULL, NULL, 0);
1769 	if (need_inplace_update(fio) &&
1770 			f2fs_lookup_extent_cache(inode, page->index, &ei)) {
1771 		fio->old_blkaddr = ei.blk + page->index - ei.fofs;
1772 
1773 		if (!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
1774 							DATA_GENERIC))
1775 			return -EFAULT;
1776 
1777 		ipu_force = true;
1778 		fio->need_lock = LOCK_DONE;
1779 		goto got_it;
1780 	}
1781 
1782 	/* Deadlock due to between page->lock and f2fs_lock_op */
1783 	if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi))
1784 		return -EAGAIN;
1785 
1786 	err = f2fs_get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1787 	if (err)
1788 		goto out;
1789 
1790 	fio->old_blkaddr = dn.data_blkaddr;
1791 
1792 	/* This page is already truncated */
1793 	if (fio->old_blkaddr == NULL_ADDR) {
1794 		ClearPageUptodate(page);
1795 		goto out_writepage;
1796 	}
1797 got_it:
1798 	if (__is_valid_data_blkaddr(fio->old_blkaddr) &&
1799 		!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
1800 							DATA_GENERIC)) {
1801 		err = -EFAULT;
1802 		goto out_writepage;
1803 	}
1804 	/*
1805 	 * If current allocation needs SSR,
1806 	 * it had better in-place writes for updated data.
1807 	 */
1808 	if (ipu_force || (is_valid_data_blkaddr(fio->sbi, fio->old_blkaddr) &&
1809 					need_inplace_update(fio))) {
1810 		err = encrypt_one_page(fio);
1811 		if (err)
1812 			goto out_writepage;
1813 
1814 		set_page_writeback(page);
1815 		ClearPageError(page);
1816 		f2fs_put_dnode(&dn);
1817 		if (fio->need_lock == LOCK_REQ)
1818 			f2fs_unlock_op(fio->sbi);
1819 		err = f2fs_inplace_write_data(fio);
1820 		trace_f2fs_do_write_data_page(fio->page, IPU);
1821 		set_inode_flag(inode, FI_UPDATE_WRITE);
1822 		return err;
1823 	}
1824 
1825 	if (fio->need_lock == LOCK_RETRY) {
1826 		if (!f2fs_trylock_op(fio->sbi)) {
1827 			err = -EAGAIN;
1828 			goto out_writepage;
1829 		}
1830 		fio->need_lock = LOCK_REQ;
1831 	}
1832 
1833 	err = f2fs_get_node_info(fio->sbi, dn.nid, &ni);
1834 	if (err)
1835 		goto out_writepage;
1836 
1837 	fio->version = ni.version;
1838 
1839 	err = encrypt_one_page(fio);
1840 	if (err)
1841 		goto out_writepage;
1842 
1843 	set_page_writeback(page);
1844 	ClearPageError(page);
1845 
1846 	/* LFS mode write path */
1847 	f2fs_outplace_write_data(&dn, fio);
1848 	trace_f2fs_do_write_data_page(page, OPU);
1849 	set_inode_flag(inode, FI_APPEND_WRITE);
1850 	if (page->index == 0)
1851 		set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1852 out_writepage:
1853 	f2fs_put_dnode(&dn);
1854 out:
1855 	if (fio->need_lock == LOCK_REQ)
1856 		f2fs_unlock_op(fio->sbi);
1857 	return err;
1858 }
1859 
1860 static int __write_data_page(struct page *page, bool *submitted,
1861 				struct writeback_control *wbc,
1862 				enum iostat_type io_type)
1863 {
1864 	struct inode *inode = page->mapping->host;
1865 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1866 	loff_t i_size = i_size_read(inode);
1867 	const pgoff_t end_index = ((unsigned long long) i_size)
1868 							>> PAGE_SHIFT;
1869 	loff_t psize = (page->index + 1) << PAGE_SHIFT;
1870 	unsigned offset = 0;
1871 	bool need_balance_fs = false;
1872 	int err = 0;
1873 	struct f2fs_io_info fio = {
1874 		.sbi = sbi,
1875 		.ino = inode->i_ino,
1876 		.type = DATA,
1877 		.op = REQ_OP_WRITE,
1878 		.op_flags = wbc_to_write_flags(wbc),
1879 		.old_blkaddr = NULL_ADDR,
1880 		.page = page,
1881 		.encrypted_page = NULL,
1882 		.submitted = false,
1883 		.need_lock = LOCK_RETRY,
1884 		.io_type = io_type,
1885 		.io_wbc = wbc,
1886 	};
1887 
1888 	trace_f2fs_writepage(page, DATA);
1889 
1890 	/* we should bypass data pages to proceed the kworkder jobs */
1891 	if (unlikely(f2fs_cp_error(sbi))) {
1892 		mapping_set_error(page->mapping, -EIO);
1893 		/*
1894 		 * don't drop any dirty dentry pages for keeping lastest
1895 		 * directory structure.
1896 		 */
1897 		if (S_ISDIR(inode->i_mode))
1898 			goto redirty_out;
1899 		goto out;
1900 	}
1901 
1902 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1903 		goto redirty_out;
1904 
1905 	if (page->index < end_index)
1906 		goto write;
1907 
1908 	/*
1909 	 * If the offset is out-of-range of file size,
1910 	 * this page does not have to be written to disk.
1911 	 */
1912 	offset = i_size & (PAGE_SIZE - 1);
1913 	if ((page->index >= end_index + 1) || !offset)
1914 		goto out;
1915 
1916 	zero_user_segment(page, offset, PAGE_SIZE);
1917 write:
1918 	if (f2fs_is_drop_cache(inode))
1919 		goto out;
1920 	/* we should not write 0'th page having journal header */
1921 	if (f2fs_is_volatile_file(inode) && (!page->index ||
1922 			(!wbc->for_reclaim &&
1923 			f2fs_available_free_memory(sbi, BASE_CHECK))))
1924 		goto redirty_out;
1925 
1926 	/* Dentry blocks are controlled by checkpoint */
1927 	if (S_ISDIR(inode->i_mode)) {
1928 		fio.need_lock = LOCK_DONE;
1929 		err = f2fs_do_write_data_page(&fio);
1930 		goto done;
1931 	}
1932 
1933 	if (!wbc->for_reclaim)
1934 		need_balance_fs = true;
1935 	else if (has_not_enough_free_secs(sbi, 0, 0))
1936 		goto redirty_out;
1937 	else
1938 		set_inode_flag(inode, FI_HOT_DATA);
1939 
1940 	err = -EAGAIN;
1941 	if (f2fs_has_inline_data(inode)) {
1942 		err = f2fs_write_inline_data(inode, page);
1943 		if (!err)
1944 			goto out;
1945 	}
1946 
1947 	if (err == -EAGAIN) {
1948 		err = f2fs_do_write_data_page(&fio);
1949 		if (err == -EAGAIN) {
1950 			fio.need_lock = LOCK_REQ;
1951 			err = f2fs_do_write_data_page(&fio);
1952 		}
1953 	}
1954 
1955 	if (err) {
1956 		file_set_keep_isize(inode);
1957 	} else {
1958 		down_write(&F2FS_I(inode)->i_sem);
1959 		if (F2FS_I(inode)->last_disk_size < psize)
1960 			F2FS_I(inode)->last_disk_size = psize;
1961 		up_write(&F2FS_I(inode)->i_sem);
1962 	}
1963 
1964 done:
1965 	if (err && err != -ENOENT)
1966 		goto redirty_out;
1967 
1968 out:
1969 	inode_dec_dirty_pages(inode);
1970 	if (err)
1971 		ClearPageUptodate(page);
1972 
1973 	if (wbc->for_reclaim) {
1974 		f2fs_submit_merged_write_cond(sbi, NULL, page, 0, DATA);
1975 		clear_inode_flag(inode, FI_HOT_DATA);
1976 		f2fs_remove_dirty_inode(inode);
1977 		submitted = NULL;
1978 	}
1979 
1980 	unlock_page(page);
1981 	if (!S_ISDIR(inode->i_mode))
1982 		f2fs_balance_fs(sbi, need_balance_fs);
1983 
1984 	if (unlikely(f2fs_cp_error(sbi))) {
1985 		f2fs_submit_merged_write(sbi, DATA);
1986 		submitted = NULL;
1987 	}
1988 
1989 	if (submitted)
1990 		*submitted = fio.submitted;
1991 
1992 	return 0;
1993 
1994 redirty_out:
1995 	redirty_page_for_writepage(wbc, page);
1996 	/*
1997 	 * pageout() in MM traslates EAGAIN, so calls handle_write_error()
1998 	 * -> mapping_set_error() -> set_bit(AS_EIO, ...).
1999 	 * file_write_and_wait_range() will see EIO error, which is critical
2000 	 * to return value of fsync() followed by atomic_write failure to user.
2001 	 */
2002 	if (!err || wbc->for_reclaim)
2003 		return AOP_WRITEPAGE_ACTIVATE;
2004 	unlock_page(page);
2005 	return err;
2006 }
2007 
2008 static int f2fs_write_data_page(struct page *page,
2009 					struct writeback_control *wbc)
2010 {
2011 	return __write_data_page(page, NULL, wbc, FS_DATA_IO);
2012 }
2013 
2014 /*
2015  * This function was copied from write_cche_pages from mm/page-writeback.c.
2016  * The major change is making write step of cold data page separately from
2017  * warm/hot data page.
2018  */
2019 static int f2fs_write_cache_pages(struct address_space *mapping,
2020 					struct writeback_control *wbc,
2021 					enum iostat_type io_type)
2022 {
2023 	int ret = 0;
2024 	int done = 0;
2025 	struct pagevec pvec;
2026 	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
2027 	int nr_pages;
2028 	pgoff_t uninitialized_var(writeback_index);
2029 	pgoff_t index;
2030 	pgoff_t end;		/* Inclusive */
2031 	pgoff_t done_index;
2032 	int cycled;
2033 	int range_whole = 0;
2034 	int tag;
2035 	int nwritten = 0;
2036 
2037 	pagevec_init(&pvec);
2038 
2039 	if (get_dirty_pages(mapping->host) <=
2040 				SM_I(F2FS_M_SB(mapping))->min_hot_blocks)
2041 		set_inode_flag(mapping->host, FI_HOT_DATA);
2042 	else
2043 		clear_inode_flag(mapping->host, FI_HOT_DATA);
2044 
2045 	if (wbc->range_cyclic) {
2046 		writeback_index = mapping->writeback_index; /* prev offset */
2047 		index = writeback_index;
2048 		if (index == 0)
2049 			cycled = 1;
2050 		else
2051 			cycled = 0;
2052 		end = -1;
2053 	} else {
2054 		index = wbc->range_start >> PAGE_SHIFT;
2055 		end = wbc->range_end >> PAGE_SHIFT;
2056 		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
2057 			range_whole = 1;
2058 		cycled = 1; /* ignore range_cyclic tests */
2059 	}
2060 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
2061 		tag = PAGECACHE_TAG_TOWRITE;
2062 	else
2063 		tag = PAGECACHE_TAG_DIRTY;
2064 retry:
2065 	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
2066 		tag_pages_for_writeback(mapping, index, end);
2067 	done_index = index;
2068 	while (!done && (index <= end)) {
2069 		int i;
2070 
2071 		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
2072 				tag);
2073 		if (nr_pages == 0)
2074 			break;
2075 
2076 		for (i = 0; i < nr_pages; i++) {
2077 			struct page *page = pvec.pages[i];
2078 			bool submitted = false;
2079 
2080 			/* give a priority to WB_SYNC threads */
2081 			if (atomic_read(&sbi->wb_sync_req[DATA]) &&
2082 					wbc->sync_mode == WB_SYNC_NONE) {
2083 				done = 1;
2084 				break;
2085 			}
2086 
2087 			done_index = page->index;
2088 retry_write:
2089 			lock_page(page);
2090 
2091 			if (unlikely(page->mapping != mapping)) {
2092 continue_unlock:
2093 				unlock_page(page);
2094 				continue;
2095 			}
2096 
2097 			if (!PageDirty(page)) {
2098 				/* someone wrote it for us */
2099 				goto continue_unlock;
2100 			}
2101 
2102 			if (PageWriteback(page)) {
2103 				if (wbc->sync_mode != WB_SYNC_NONE)
2104 					f2fs_wait_on_page_writeback(page,
2105 								DATA, true);
2106 				else
2107 					goto continue_unlock;
2108 			}
2109 
2110 			BUG_ON(PageWriteback(page));
2111 			if (!clear_page_dirty_for_io(page))
2112 				goto continue_unlock;
2113 
2114 			ret = __write_data_page(page, &submitted, wbc, io_type);
2115 			if (unlikely(ret)) {
2116 				/*
2117 				 * keep nr_to_write, since vfs uses this to
2118 				 * get # of written pages.
2119 				 */
2120 				if (ret == AOP_WRITEPAGE_ACTIVATE) {
2121 					unlock_page(page);
2122 					ret = 0;
2123 					continue;
2124 				} else if (ret == -EAGAIN) {
2125 					ret = 0;
2126 					if (wbc->sync_mode == WB_SYNC_ALL) {
2127 						cond_resched();
2128 						congestion_wait(BLK_RW_ASYNC,
2129 									HZ/50);
2130 						goto retry_write;
2131 					}
2132 					continue;
2133 				}
2134 				done_index = page->index + 1;
2135 				done = 1;
2136 				break;
2137 			} else if (submitted) {
2138 				nwritten++;
2139 			}
2140 
2141 			if (--wbc->nr_to_write <= 0 &&
2142 					wbc->sync_mode == WB_SYNC_NONE) {
2143 				done = 1;
2144 				break;
2145 			}
2146 		}
2147 		pagevec_release(&pvec);
2148 		cond_resched();
2149 	}
2150 
2151 	if (!cycled && !done) {
2152 		cycled = 1;
2153 		index = 0;
2154 		end = writeback_index - 1;
2155 		goto retry;
2156 	}
2157 	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
2158 		mapping->writeback_index = done_index;
2159 
2160 	if (nwritten)
2161 		f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
2162 								NULL, 0, DATA);
2163 
2164 	return ret;
2165 }
2166 
2167 static inline bool __should_serialize_io(struct inode *inode,
2168 					struct writeback_control *wbc)
2169 {
2170 	if (!S_ISREG(inode->i_mode))
2171 		return false;
2172 	if (wbc->sync_mode != WB_SYNC_ALL)
2173 		return true;
2174 	if (get_dirty_pages(inode) >= SM_I(F2FS_I_SB(inode))->min_seq_blocks)
2175 		return true;
2176 	return false;
2177 }
2178 
2179 static int __f2fs_write_data_pages(struct address_space *mapping,
2180 						struct writeback_control *wbc,
2181 						enum iostat_type io_type)
2182 {
2183 	struct inode *inode = mapping->host;
2184 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2185 	struct blk_plug plug;
2186 	int ret;
2187 	bool locked = false;
2188 
2189 	/* deal with chardevs and other special file */
2190 	if (!mapping->a_ops->writepage)
2191 		return 0;
2192 
2193 	/* skip writing if there is no dirty page in this inode */
2194 	if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
2195 		return 0;
2196 
2197 	/* during POR, we don't need to trigger writepage at all. */
2198 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
2199 		goto skip_write;
2200 
2201 	if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
2202 			get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
2203 			f2fs_available_free_memory(sbi, DIRTY_DENTS))
2204 		goto skip_write;
2205 
2206 	/* skip writing during file defragment */
2207 	if (is_inode_flag_set(inode, FI_DO_DEFRAG))
2208 		goto skip_write;
2209 
2210 	trace_f2fs_writepages(mapping->host, wbc, DATA);
2211 
2212 	/* to avoid spliting IOs due to mixed WB_SYNC_ALL and WB_SYNC_NONE */
2213 	if (wbc->sync_mode == WB_SYNC_ALL)
2214 		atomic_inc(&sbi->wb_sync_req[DATA]);
2215 	else if (atomic_read(&sbi->wb_sync_req[DATA]))
2216 		goto skip_write;
2217 
2218 	if (__should_serialize_io(inode, wbc)) {
2219 		mutex_lock(&sbi->writepages);
2220 		locked = true;
2221 	}
2222 
2223 	blk_start_plug(&plug);
2224 	ret = f2fs_write_cache_pages(mapping, wbc, io_type);
2225 	blk_finish_plug(&plug);
2226 
2227 	if (locked)
2228 		mutex_unlock(&sbi->writepages);
2229 
2230 	if (wbc->sync_mode == WB_SYNC_ALL)
2231 		atomic_dec(&sbi->wb_sync_req[DATA]);
2232 	/*
2233 	 * if some pages were truncated, we cannot guarantee its mapping->host
2234 	 * to detect pending bios.
2235 	 */
2236 
2237 	f2fs_remove_dirty_inode(inode);
2238 	return ret;
2239 
2240 skip_write:
2241 	wbc->pages_skipped += get_dirty_pages(inode);
2242 	trace_f2fs_writepages(mapping->host, wbc, DATA);
2243 	return 0;
2244 }
2245 
2246 static int f2fs_write_data_pages(struct address_space *mapping,
2247 			    struct writeback_control *wbc)
2248 {
2249 	struct inode *inode = mapping->host;
2250 
2251 	return __f2fs_write_data_pages(mapping, wbc,
2252 			F2FS_I(inode)->cp_task == current ?
2253 			FS_CP_DATA_IO : FS_DATA_IO);
2254 }
2255 
2256 static void f2fs_write_failed(struct address_space *mapping, loff_t to)
2257 {
2258 	struct inode *inode = mapping->host;
2259 	loff_t i_size = i_size_read(inode);
2260 
2261 	if (to > i_size) {
2262 		down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
2263 		down_write(&F2FS_I(inode)->i_mmap_sem);
2264 
2265 		truncate_pagecache(inode, i_size);
2266 		f2fs_truncate_blocks(inode, i_size, true);
2267 
2268 		up_write(&F2FS_I(inode)->i_mmap_sem);
2269 		up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
2270 	}
2271 }
2272 
2273 static int prepare_write_begin(struct f2fs_sb_info *sbi,
2274 			struct page *page, loff_t pos, unsigned len,
2275 			block_t *blk_addr, bool *node_changed)
2276 {
2277 	struct inode *inode = page->mapping->host;
2278 	pgoff_t index = page->index;
2279 	struct dnode_of_data dn;
2280 	struct page *ipage;
2281 	bool locked = false;
2282 	struct extent_info ei = {0,0,0};
2283 	int err = 0;
2284 
2285 	/*
2286 	 * we already allocated all the blocks, so we don't need to get
2287 	 * the block addresses when there is no need to fill the page.
2288 	 */
2289 	if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
2290 			!is_inode_flag_set(inode, FI_NO_PREALLOC))
2291 		return 0;
2292 
2293 	if (f2fs_has_inline_data(inode) ||
2294 			(pos & PAGE_MASK) >= i_size_read(inode)) {
2295 		__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
2296 		locked = true;
2297 	}
2298 restart:
2299 	/* check inline_data */
2300 	ipage = f2fs_get_node_page(sbi, inode->i_ino);
2301 	if (IS_ERR(ipage)) {
2302 		err = PTR_ERR(ipage);
2303 		goto unlock_out;
2304 	}
2305 
2306 	set_new_dnode(&dn, inode, ipage, ipage, 0);
2307 
2308 	if (f2fs_has_inline_data(inode)) {
2309 		if (pos + len <= MAX_INLINE_DATA(inode)) {
2310 			f2fs_do_read_inline_data(page, ipage);
2311 			set_inode_flag(inode, FI_DATA_EXIST);
2312 			if (inode->i_nlink)
2313 				set_inline_node(ipage);
2314 		} else {
2315 			err = f2fs_convert_inline_page(&dn, page);
2316 			if (err)
2317 				goto out;
2318 			if (dn.data_blkaddr == NULL_ADDR)
2319 				err = f2fs_get_block(&dn, index);
2320 		}
2321 	} else if (locked) {
2322 		err = f2fs_get_block(&dn, index);
2323 	} else {
2324 		if (f2fs_lookup_extent_cache(inode, index, &ei)) {
2325 			dn.data_blkaddr = ei.blk + index - ei.fofs;
2326 		} else {
2327 			/* hole case */
2328 			err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
2329 			if (err || dn.data_blkaddr == NULL_ADDR) {
2330 				f2fs_put_dnode(&dn);
2331 				__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO,
2332 								true);
2333 				locked = true;
2334 				goto restart;
2335 			}
2336 		}
2337 	}
2338 
2339 	/* convert_inline_page can make node_changed */
2340 	*blk_addr = dn.data_blkaddr;
2341 	*node_changed = dn.node_changed;
2342 out:
2343 	f2fs_put_dnode(&dn);
2344 unlock_out:
2345 	if (locked)
2346 		__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
2347 	return err;
2348 }
2349 
2350 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
2351 		loff_t pos, unsigned len, unsigned flags,
2352 		struct page **pagep, void **fsdata)
2353 {
2354 	struct inode *inode = mapping->host;
2355 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2356 	struct page *page = NULL;
2357 	pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
2358 	bool need_balance = false, drop_atomic = false;
2359 	block_t blkaddr = NULL_ADDR;
2360 	int err = 0;
2361 
2362 	trace_f2fs_write_begin(inode, pos, len, flags);
2363 
2364 	err = f2fs_is_checkpoint_ready(sbi);
2365 	if (err)
2366 		goto fail;
2367 
2368 	if ((f2fs_is_atomic_file(inode) &&
2369 			!f2fs_available_free_memory(sbi, INMEM_PAGES)) ||
2370 			is_inode_flag_set(inode, FI_ATOMIC_REVOKE_REQUEST)) {
2371 		err = -ENOMEM;
2372 		drop_atomic = true;
2373 		goto fail;
2374 	}
2375 
2376 	/*
2377 	 * We should check this at this moment to avoid deadlock on inode page
2378 	 * and #0 page. The locking rule for inline_data conversion should be:
2379 	 * lock_page(page #0) -> lock_page(inode_page)
2380 	 */
2381 	if (index != 0) {
2382 		err = f2fs_convert_inline_inode(inode);
2383 		if (err)
2384 			goto fail;
2385 	}
2386 repeat:
2387 	/*
2388 	 * Do not use grab_cache_page_write_begin() to avoid deadlock due to
2389 	 * wait_for_stable_page. Will wait that below with our IO control.
2390 	 */
2391 	page = f2fs_pagecache_get_page(mapping, index,
2392 				FGP_LOCK | FGP_WRITE | FGP_CREAT, GFP_NOFS);
2393 	if (!page) {
2394 		err = -ENOMEM;
2395 		goto fail;
2396 	}
2397 
2398 	*pagep = page;
2399 
2400 	err = prepare_write_begin(sbi, page, pos, len,
2401 					&blkaddr, &need_balance);
2402 	if (err)
2403 		goto fail;
2404 
2405 	if (need_balance && has_not_enough_free_secs(sbi, 0, 0)) {
2406 		unlock_page(page);
2407 		f2fs_balance_fs(sbi, true);
2408 		lock_page(page);
2409 		if (page->mapping != mapping) {
2410 			/* The page got truncated from under us */
2411 			f2fs_put_page(page, 1);
2412 			goto repeat;
2413 		}
2414 	}
2415 
2416 	f2fs_wait_on_page_writeback(page, DATA, false);
2417 
2418 	if (len == PAGE_SIZE || PageUptodate(page))
2419 		return 0;
2420 
2421 	if (!(pos & (PAGE_SIZE - 1)) && (pos + len) >= i_size_read(inode)) {
2422 		zero_user_segment(page, len, PAGE_SIZE);
2423 		return 0;
2424 	}
2425 
2426 	if (blkaddr == NEW_ADDR) {
2427 		zero_user_segment(page, 0, PAGE_SIZE);
2428 		SetPageUptodate(page);
2429 	} else {
2430 		err = f2fs_submit_page_read(inode, page, blkaddr);
2431 		if (err)
2432 			goto fail;
2433 
2434 		lock_page(page);
2435 		if (unlikely(page->mapping != mapping)) {
2436 			f2fs_put_page(page, 1);
2437 			goto repeat;
2438 		}
2439 		if (unlikely(!PageUptodate(page))) {
2440 			err = -EIO;
2441 			goto fail;
2442 		}
2443 	}
2444 	return 0;
2445 
2446 fail:
2447 	f2fs_put_page(page, 1);
2448 	f2fs_write_failed(mapping, pos + len);
2449 	if (drop_atomic)
2450 		f2fs_drop_inmem_pages_all(sbi, false);
2451 	return err;
2452 }
2453 
2454 static int f2fs_write_end(struct file *file,
2455 			struct address_space *mapping,
2456 			loff_t pos, unsigned len, unsigned copied,
2457 			struct page *page, void *fsdata)
2458 {
2459 	struct inode *inode = page->mapping->host;
2460 
2461 	trace_f2fs_write_end(inode, pos, len, copied);
2462 
2463 	/*
2464 	 * This should be come from len == PAGE_SIZE, and we expect copied
2465 	 * should be PAGE_SIZE. Otherwise, we treat it with zero copied and
2466 	 * let generic_perform_write() try to copy data again through copied=0.
2467 	 */
2468 	if (!PageUptodate(page)) {
2469 		if (unlikely(copied != len))
2470 			copied = 0;
2471 		else
2472 			SetPageUptodate(page);
2473 	}
2474 	if (!copied)
2475 		goto unlock_out;
2476 
2477 	set_page_dirty(page);
2478 
2479 	if (pos + copied > i_size_read(inode))
2480 		f2fs_i_size_write(inode, pos + copied);
2481 unlock_out:
2482 	f2fs_put_page(page, 1);
2483 	f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
2484 	return copied;
2485 }
2486 
2487 static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
2488 			   loff_t offset)
2489 {
2490 	unsigned i_blkbits = READ_ONCE(inode->i_blkbits);
2491 	unsigned blkbits = i_blkbits;
2492 	unsigned blocksize_mask = (1 << blkbits) - 1;
2493 	unsigned long align = offset | iov_iter_alignment(iter);
2494 	struct block_device *bdev = inode->i_sb->s_bdev;
2495 
2496 	if (align & blocksize_mask) {
2497 		if (bdev)
2498 			blkbits = blksize_bits(bdev_logical_block_size(bdev));
2499 		blocksize_mask = (1 << blkbits) - 1;
2500 		if (align & blocksize_mask)
2501 			return -EINVAL;
2502 		return 1;
2503 	}
2504 	return 0;
2505 }
2506 
2507 static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
2508 {
2509 	struct address_space *mapping = iocb->ki_filp->f_mapping;
2510 	struct inode *inode = mapping->host;
2511 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2512 	struct f2fs_inode_info *fi = F2FS_I(inode);
2513 	size_t count = iov_iter_count(iter);
2514 	loff_t offset = iocb->ki_pos;
2515 	int rw = iov_iter_rw(iter);
2516 	int err;
2517 	enum rw_hint hint = iocb->ki_hint;
2518 	int whint_mode = F2FS_OPTION(sbi).whint_mode;
2519 	bool do_opu;
2520 
2521 	err = check_direct_IO(inode, iter, offset);
2522 	if (err)
2523 		return err < 0 ? err : 0;
2524 
2525 	if (f2fs_force_buffered_io(inode, iocb, iter))
2526 		return 0;
2527 
2528 	do_opu = allow_outplace_dio(inode, iocb, iter);
2529 
2530 	trace_f2fs_direct_IO_enter(inode, offset, count, rw);
2531 
2532 	if (rw == WRITE && whint_mode == WHINT_MODE_OFF)
2533 		iocb->ki_hint = WRITE_LIFE_NOT_SET;
2534 
2535 	if (iocb->ki_flags & IOCB_NOWAIT) {
2536 		if (!down_read_trylock(&fi->i_gc_rwsem[rw])) {
2537 			iocb->ki_hint = hint;
2538 			err = -EAGAIN;
2539 			goto out;
2540 		}
2541 		if (do_opu && !down_read_trylock(&fi->i_gc_rwsem[READ])) {
2542 			up_read(&fi->i_gc_rwsem[rw]);
2543 			iocb->ki_hint = hint;
2544 			err = -EAGAIN;
2545 			goto out;
2546 		}
2547 	} else {
2548 		down_read(&fi->i_gc_rwsem[rw]);
2549 		if (do_opu)
2550 			down_read(&fi->i_gc_rwsem[READ]);
2551 	}
2552 
2553 	err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
2554 
2555 	if (do_opu)
2556 		up_read(&fi->i_gc_rwsem[READ]);
2557 
2558 	up_read(&fi->i_gc_rwsem[rw]);
2559 
2560 	if (rw == WRITE) {
2561 		if (whint_mode == WHINT_MODE_OFF)
2562 			iocb->ki_hint = hint;
2563 		if (err > 0) {
2564 			f2fs_update_iostat(F2FS_I_SB(inode), APP_DIRECT_IO,
2565 									err);
2566 			if (!do_opu)
2567 				set_inode_flag(inode, FI_UPDATE_WRITE);
2568 		} else if (err < 0) {
2569 			f2fs_write_failed(mapping, offset + count);
2570 		}
2571 	}
2572 
2573 out:
2574 	trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
2575 
2576 	return err;
2577 }
2578 
2579 void f2fs_invalidate_page(struct page *page, unsigned int offset,
2580 							unsigned int length)
2581 {
2582 	struct inode *inode = page->mapping->host;
2583 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2584 
2585 	if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
2586 		(offset % PAGE_SIZE || length != PAGE_SIZE))
2587 		return;
2588 
2589 	if (PageDirty(page)) {
2590 		if (inode->i_ino == F2FS_META_INO(sbi)) {
2591 			dec_page_count(sbi, F2FS_DIRTY_META);
2592 		} else if (inode->i_ino == F2FS_NODE_INO(sbi)) {
2593 			dec_page_count(sbi, F2FS_DIRTY_NODES);
2594 		} else {
2595 			inode_dec_dirty_pages(inode);
2596 			f2fs_remove_dirty_inode(inode);
2597 		}
2598 	}
2599 
2600 	/* This is atomic written page, keep Private */
2601 	if (IS_ATOMIC_WRITTEN_PAGE(page))
2602 		return f2fs_drop_inmem_page(inode, page);
2603 
2604 	set_page_private(page, 0);
2605 	ClearPagePrivate(page);
2606 }
2607 
2608 int f2fs_release_page(struct page *page, gfp_t wait)
2609 {
2610 	/* If this is dirty page, keep PagePrivate */
2611 	if (PageDirty(page))
2612 		return 0;
2613 
2614 	/* This is atomic written page, keep Private */
2615 	if (IS_ATOMIC_WRITTEN_PAGE(page))
2616 		return 0;
2617 
2618 	set_page_private(page, 0);
2619 	ClearPagePrivate(page);
2620 	return 1;
2621 }
2622 
2623 static int f2fs_set_data_page_dirty(struct page *page)
2624 {
2625 	struct address_space *mapping = page->mapping;
2626 	struct inode *inode = mapping->host;
2627 
2628 	trace_f2fs_set_page_dirty(page, DATA);
2629 
2630 	if (!PageUptodate(page))
2631 		SetPageUptodate(page);
2632 
2633 	/* don't remain PG_checked flag which was set during GC */
2634 	if (is_cold_data(page))
2635 		clear_cold_data(page);
2636 
2637 	if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
2638 		if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
2639 			f2fs_register_inmem_page(inode, page);
2640 			return 1;
2641 		}
2642 		/*
2643 		 * Previously, this page has been registered, we just
2644 		 * return here.
2645 		 */
2646 		return 0;
2647 	}
2648 
2649 	if (!PageDirty(page)) {
2650 		__set_page_dirty_nobuffers(page);
2651 		f2fs_update_dirty_page(inode, page);
2652 		return 1;
2653 	}
2654 	return 0;
2655 }
2656 
2657 static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
2658 {
2659 	struct inode *inode = mapping->host;
2660 
2661 	if (f2fs_has_inline_data(inode))
2662 		return 0;
2663 
2664 	/* make sure allocating whole blocks */
2665 	if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
2666 		filemap_write_and_wait(mapping);
2667 
2668 	return generic_block_bmap(mapping, block, get_data_block_bmap);
2669 }
2670 
2671 #ifdef CONFIG_MIGRATION
2672 #include <linux/migrate.h>
2673 
2674 int f2fs_migrate_page(struct address_space *mapping,
2675 		struct page *newpage, struct page *page, enum migrate_mode mode)
2676 {
2677 	int rc, extra_count;
2678 	struct f2fs_inode_info *fi = F2FS_I(mapping->host);
2679 	bool atomic_written = IS_ATOMIC_WRITTEN_PAGE(page);
2680 
2681 	BUG_ON(PageWriteback(page));
2682 
2683 	/* migrating an atomic written page is safe with the inmem_lock hold */
2684 	if (atomic_written) {
2685 		if (mode != MIGRATE_SYNC)
2686 			return -EBUSY;
2687 		if (!mutex_trylock(&fi->inmem_lock))
2688 			return -EAGAIN;
2689 	}
2690 
2691 	/*
2692 	 * A reference is expected if PagePrivate set when move mapping,
2693 	 * however F2FS breaks this for maintaining dirty page counts when
2694 	 * truncating pages. So here adjusting the 'extra_count' make it work.
2695 	 */
2696 	extra_count = (atomic_written ? 1 : 0) - page_has_private(page);
2697 	rc = migrate_page_move_mapping(mapping, newpage,
2698 				page, NULL, mode, extra_count);
2699 	if (rc != MIGRATEPAGE_SUCCESS) {
2700 		if (atomic_written)
2701 			mutex_unlock(&fi->inmem_lock);
2702 		return rc;
2703 	}
2704 
2705 	if (atomic_written) {
2706 		struct inmem_pages *cur;
2707 		list_for_each_entry(cur, &fi->inmem_pages, list)
2708 			if (cur->page == page) {
2709 				cur->page = newpage;
2710 				break;
2711 			}
2712 		mutex_unlock(&fi->inmem_lock);
2713 		put_page(page);
2714 		get_page(newpage);
2715 	}
2716 
2717 	if (PagePrivate(page))
2718 		SetPagePrivate(newpage);
2719 	set_page_private(newpage, page_private(page));
2720 
2721 	if (mode != MIGRATE_SYNC_NO_COPY)
2722 		migrate_page_copy(newpage, page);
2723 	else
2724 		migrate_page_states(newpage, page);
2725 
2726 	return MIGRATEPAGE_SUCCESS;
2727 }
2728 #endif
2729 
2730 const struct address_space_operations f2fs_dblock_aops = {
2731 	.readpage	= f2fs_read_data_page,
2732 	.readpages	= f2fs_read_data_pages,
2733 	.writepage	= f2fs_write_data_page,
2734 	.writepages	= f2fs_write_data_pages,
2735 	.write_begin	= f2fs_write_begin,
2736 	.write_end	= f2fs_write_end,
2737 	.set_page_dirty	= f2fs_set_data_page_dirty,
2738 	.invalidatepage	= f2fs_invalidate_page,
2739 	.releasepage	= f2fs_release_page,
2740 	.direct_IO	= f2fs_direct_IO,
2741 	.bmap		= f2fs_bmap,
2742 #ifdef CONFIG_MIGRATION
2743 	.migratepage    = f2fs_migrate_page,
2744 #endif
2745 };
2746 
2747 void f2fs_clear_radix_tree_dirty_tag(struct page *page)
2748 {
2749 	struct address_space *mapping = page_mapping(page);
2750 	unsigned long flags;
2751 
2752 	xa_lock_irqsave(&mapping->i_pages, flags);
2753 	radix_tree_tag_clear(&mapping->i_pages, page_index(page),
2754 						PAGECACHE_TAG_DIRTY);
2755 	xa_unlock_irqrestore(&mapping->i_pages, flags);
2756 }
2757 
2758 int __init f2fs_init_post_read_processing(void)
2759 {
2760 	bio_post_read_ctx_cache = KMEM_CACHE(bio_post_read_ctx, 0);
2761 	if (!bio_post_read_ctx_cache)
2762 		goto fail;
2763 	bio_post_read_ctx_pool =
2764 		mempool_create_slab_pool(NUM_PREALLOC_POST_READ_CTXS,
2765 					 bio_post_read_ctx_cache);
2766 	if (!bio_post_read_ctx_pool)
2767 		goto fail_free_cache;
2768 	return 0;
2769 
2770 fail_free_cache:
2771 	kmem_cache_destroy(bio_post_read_ctx_cache);
2772 fail:
2773 	return -ENOMEM;
2774 }
2775 
2776 void __exit f2fs_destroy_post_read_processing(void)
2777 {
2778 	mempool_destroy(bio_post_read_ctx_pool);
2779 	kmem_cache_destroy(bio_post_read_ctx_cache);
2780 }
2781