xref: /linux/fs/f2fs/checkpoint.c (revision 1c71222e5f2393b5ea1a41795c67589eea7e3490)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * fs/f2fs/checkpoint.c
4  *
5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6  *             http://www.samsung.com/
7  */
8 #include <linux/fs.h>
9 #include <linux/bio.h>
10 #include <linux/mpage.h>
11 #include <linux/writeback.h>
12 #include <linux/blkdev.h>
13 #include <linux/f2fs_fs.h>
14 #include <linux/pagevec.h>
15 #include <linux/swap.h>
16 #include <linux/kthread.h>
17 
18 #include "f2fs.h"
19 #include "node.h"
20 #include "segment.h"
21 #include "iostat.h"
22 #include <trace/events/f2fs.h>
23 
24 #define DEFAULT_CHECKPOINT_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
25 
26 static struct kmem_cache *ino_entry_slab;
27 struct kmem_cache *f2fs_inode_entry_slab;
28 
29 void f2fs_stop_checkpoint(struct f2fs_sb_info *sbi, bool end_io,
30 						unsigned char reason)
31 {
32 	f2fs_build_fault_attr(sbi, 0, 0);
33 	set_ckpt_flags(sbi, CP_ERROR_FLAG);
34 	if (!end_io) {
35 		f2fs_flush_merged_writes(sbi);
36 
37 		f2fs_handle_stop(sbi, reason);
38 	}
39 }
40 
41 /*
42  * We guarantee no failure on the returned page.
43  */
44 struct page *f2fs_grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
45 {
46 	struct address_space *mapping = META_MAPPING(sbi);
47 	struct page *page;
48 repeat:
49 	page = f2fs_grab_cache_page(mapping, index, false);
50 	if (!page) {
51 		cond_resched();
52 		goto repeat;
53 	}
54 	f2fs_wait_on_page_writeback(page, META, true, true);
55 	if (!PageUptodate(page))
56 		SetPageUptodate(page);
57 	return page;
58 }
59 
60 static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
61 							bool is_meta)
62 {
63 	struct address_space *mapping = META_MAPPING(sbi);
64 	struct page *page;
65 	struct f2fs_io_info fio = {
66 		.sbi = sbi,
67 		.type = META,
68 		.op = REQ_OP_READ,
69 		.op_flags = REQ_META | REQ_PRIO,
70 		.old_blkaddr = index,
71 		.new_blkaddr = index,
72 		.encrypted_page = NULL,
73 		.is_por = !is_meta,
74 	};
75 	int err;
76 
77 	if (unlikely(!is_meta))
78 		fio.op_flags &= ~REQ_META;
79 repeat:
80 	page = f2fs_grab_cache_page(mapping, index, false);
81 	if (!page) {
82 		cond_resched();
83 		goto repeat;
84 	}
85 	if (PageUptodate(page))
86 		goto out;
87 
88 	fio.page = page;
89 
90 	err = f2fs_submit_page_bio(&fio);
91 	if (err) {
92 		f2fs_put_page(page, 1);
93 		return ERR_PTR(err);
94 	}
95 
96 	f2fs_update_iostat(sbi, NULL, FS_META_READ_IO, F2FS_BLKSIZE);
97 
98 	lock_page(page);
99 	if (unlikely(page->mapping != mapping)) {
100 		f2fs_put_page(page, 1);
101 		goto repeat;
102 	}
103 
104 	if (unlikely(!PageUptodate(page))) {
105 		f2fs_handle_page_eio(sbi, page->index, META);
106 		f2fs_put_page(page, 1);
107 		return ERR_PTR(-EIO);
108 	}
109 out:
110 	return page;
111 }
112 
113 struct page *f2fs_get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
114 {
115 	return __get_meta_page(sbi, index, true);
116 }
117 
118 struct page *f2fs_get_meta_page_retry(struct f2fs_sb_info *sbi, pgoff_t index)
119 {
120 	struct page *page;
121 	int count = 0;
122 
123 retry:
124 	page = __get_meta_page(sbi, index, true);
125 	if (IS_ERR(page)) {
126 		if (PTR_ERR(page) == -EIO &&
127 				++count <= DEFAULT_RETRY_IO_COUNT)
128 			goto retry;
129 		f2fs_stop_checkpoint(sbi, false, STOP_CP_REASON_META_PAGE);
130 	}
131 	return page;
132 }
133 
134 /* for POR only */
135 struct page *f2fs_get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index)
136 {
137 	return __get_meta_page(sbi, index, false);
138 }
139 
140 static bool __is_bitmap_valid(struct f2fs_sb_info *sbi, block_t blkaddr,
141 							int type)
142 {
143 	struct seg_entry *se;
144 	unsigned int segno, offset;
145 	bool exist;
146 
147 	if (type == DATA_GENERIC)
148 		return true;
149 
150 	segno = GET_SEGNO(sbi, blkaddr);
151 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
152 	se = get_seg_entry(sbi, segno);
153 
154 	exist = f2fs_test_bit(offset, se->cur_valid_map);
155 	if (exist && type == DATA_GENERIC_ENHANCE_UPDATE) {
156 		f2fs_err(sbi, "Inconsistent error blkaddr:%u, sit bitmap:%d",
157 			 blkaddr, exist);
158 		set_sbi_flag(sbi, SBI_NEED_FSCK);
159 		return exist;
160 	}
161 
162 	if (!exist && type == DATA_GENERIC_ENHANCE) {
163 		f2fs_err(sbi, "Inconsistent error blkaddr:%u, sit bitmap:%d",
164 			 blkaddr, exist);
165 		set_sbi_flag(sbi, SBI_NEED_FSCK);
166 		dump_stack();
167 	}
168 	return exist;
169 }
170 
171 bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
172 					block_t blkaddr, int type)
173 {
174 	if (time_to_inject(sbi, FAULT_BLKADDR)) {
175 		f2fs_show_injection_info(sbi, FAULT_BLKADDR);
176 		return false;
177 	}
178 
179 	switch (type) {
180 	case META_NAT:
181 		break;
182 	case META_SIT:
183 		if (unlikely(blkaddr >= SIT_BLK_CNT(sbi)))
184 			return false;
185 		break;
186 	case META_SSA:
187 		if (unlikely(blkaddr >= MAIN_BLKADDR(sbi) ||
188 			blkaddr < SM_I(sbi)->ssa_blkaddr))
189 			return false;
190 		break;
191 	case META_CP:
192 		if (unlikely(blkaddr >= SIT_I(sbi)->sit_base_addr ||
193 			blkaddr < __start_cp_addr(sbi)))
194 			return false;
195 		break;
196 	case META_POR:
197 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
198 			blkaddr < MAIN_BLKADDR(sbi)))
199 			return false;
200 		break;
201 	case DATA_GENERIC:
202 	case DATA_GENERIC_ENHANCE:
203 	case DATA_GENERIC_ENHANCE_READ:
204 	case DATA_GENERIC_ENHANCE_UPDATE:
205 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
206 				blkaddr < MAIN_BLKADDR(sbi))) {
207 			f2fs_warn(sbi, "access invalid blkaddr:%u",
208 				  blkaddr);
209 			set_sbi_flag(sbi, SBI_NEED_FSCK);
210 			dump_stack();
211 			return false;
212 		} else {
213 			return __is_bitmap_valid(sbi, blkaddr, type);
214 		}
215 		break;
216 	case META_GENERIC:
217 		if (unlikely(blkaddr < SEG0_BLKADDR(sbi) ||
218 			blkaddr >= MAIN_BLKADDR(sbi)))
219 			return false;
220 		break;
221 	default:
222 		BUG();
223 	}
224 
225 	return true;
226 }
227 
228 /*
229  * Readahead CP/NAT/SIT/SSA/POR pages
230  */
231 int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
232 							int type, bool sync)
233 {
234 	struct page *page;
235 	block_t blkno = start;
236 	struct f2fs_io_info fio = {
237 		.sbi = sbi,
238 		.type = META,
239 		.op = REQ_OP_READ,
240 		.op_flags = sync ? (REQ_META | REQ_PRIO) : REQ_RAHEAD,
241 		.encrypted_page = NULL,
242 		.in_list = false,
243 		.is_por = (type == META_POR),
244 	};
245 	struct blk_plug plug;
246 	int err;
247 
248 	if (unlikely(type == META_POR))
249 		fio.op_flags &= ~REQ_META;
250 
251 	blk_start_plug(&plug);
252 	for (; nrpages-- > 0; blkno++) {
253 
254 		if (!f2fs_is_valid_blkaddr(sbi, blkno, type))
255 			goto out;
256 
257 		switch (type) {
258 		case META_NAT:
259 			if (unlikely(blkno >=
260 					NAT_BLOCK_OFFSET(NM_I(sbi)->max_nid)))
261 				blkno = 0;
262 			/* get nat block addr */
263 			fio.new_blkaddr = current_nat_addr(sbi,
264 					blkno * NAT_ENTRY_PER_BLOCK);
265 			break;
266 		case META_SIT:
267 			if (unlikely(blkno >= TOTAL_SEGS(sbi)))
268 				goto out;
269 			/* get sit block addr */
270 			fio.new_blkaddr = current_sit_addr(sbi,
271 					blkno * SIT_ENTRY_PER_BLOCK);
272 			break;
273 		case META_SSA:
274 		case META_CP:
275 		case META_POR:
276 			fio.new_blkaddr = blkno;
277 			break;
278 		default:
279 			BUG();
280 		}
281 
282 		page = f2fs_grab_cache_page(META_MAPPING(sbi),
283 						fio.new_blkaddr, false);
284 		if (!page)
285 			continue;
286 		if (PageUptodate(page)) {
287 			f2fs_put_page(page, 1);
288 			continue;
289 		}
290 
291 		fio.page = page;
292 		err = f2fs_submit_page_bio(&fio);
293 		f2fs_put_page(page, err ? 1 : 0);
294 
295 		if (!err)
296 			f2fs_update_iostat(sbi, NULL, FS_META_READ_IO,
297 							F2FS_BLKSIZE);
298 	}
299 out:
300 	blk_finish_plug(&plug);
301 	return blkno - start;
302 }
303 
304 void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index,
305 							unsigned int ra_blocks)
306 {
307 	struct page *page;
308 	bool readahead = false;
309 
310 	if (ra_blocks == RECOVERY_MIN_RA_BLOCKS)
311 		return;
312 
313 	page = find_get_page(META_MAPPING(sbi), index);
314 	if (!page || !PageUptodate(page))
315 		readahead = true;
316 	f2fs_put_page(page, 0);
317 
318 	if (readahead)
319 		f2fs_ra_meta_pages(sbi, index, ra_blocks, META_POR, true);
320 }
321 
322 static int __f2fs_write_meta_page(struct page *page,
323 				struct writeback_control *wbc,
324 				enum iostat_type io_type)
325 {
326 	struct f2fs_sb_info *sbi = F2FS_P_SB(page);
327 
328 	trace_f2fs_writepage(page, META);
329 
330 	if (unlikely(f2fs_cp_error(sbi)))
331 		goto redirty_out;
332 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
333 		goto redirty_out;
334 	if (wbc->for_reclaim && page->index < GET_SUM_BLOCK(sbi, 0))
335 		goto redirty_out;
336 
337 	f2fs_do_write_meta_page(sbi, page, io_type);
338 	dec_page_count(sbi, F2FS_DIRTY_META);
339 
340 	if (wbc->for_reclaim)
341 		f2fs_submit_merged_write_cond(sbi, NULL, page, 0, META);
342 
343 	unlock_page(page);
344 
345 	if (unlikely(f2fs_cp_error(sbi)))
346 		f2fs_submit_merged_write(sbi, META);
347 
348 	return 0;
349 
350 redirty_out:
351 	redirty_page_for_writepage(wbc, page);
352 	return AOP_WRITEPAGE_ACTIVATE;
353 }
354 
355 static int f2fs_write_meta_page(struct page *page,
356 				struct writeback_control *wbc)
357 {
358 	return __f2fs_write_meta_page(page, wbc, FS_META_IO);
359 }
360 
361 static int f2fs_write_meta_pages(struct address_space *mapping,
362 				struct writeback_control *wbc)
363 {
364 	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
365 	long diff, written;
366 
367 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
368 		goto skip_write;
369 
370 	/* collect a number of dirty meta pages and write together */
371 	if (wbc->sync_mode != WB_SYNC_ALL &&
372 			get_pages(sbi, F2FS_DIRTY_META) <
373 					nr_pages_to_skip(sbi, META))
374 		goto skip_write;
375 
376 	/* if locked failed, cp will flush dirty pages instead */
377 	if (!f2fs_down_write_trylock(&sbi->cp_global_sem))
378 		goto skip_write;
379 
380 	trace_f2fs_writepages(mapping->host, wbc, META);
381 	diff = nr_pages_to_write(sbi, META, wbc);
382 	written = f2fs_sync_meta_pages(sbi, META, wbc->nr_to_write, FS_META_IO);
383 	f2fs_up_write(&sbi->cp_global_sem);
384 	wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff);
385 	return 0;
386 
387 skip_write:
388 	wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_META);
389 	trace_f2fs_writepages(mapping->host, wbc, META);
390 	return 0;
391 }
392 
393 long f2fs_sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
394 				long nr_to_write, enum iostat_type io_type)
395 {
396 	struct address_space *mapping = META_MAPPING(sbi);
397 	pgoff_t index = 0, prev = ULONG_MAX;
398 	struct folio_batch fbatch;
399 	long nwritten = 0;
400 	int nr_folios;
401 	struct writeback_control wbc = {
402 		.for_reclaim = 0,
403 	};
404 	struct blk_plug plug;
405 
406 	folio_batch_init(&fbatch);
407 
408 	blk_start_plug(&plug);
409 
410 	while ((nr_folios = filemap_get_folios_tag(mapping, &index,
411 					(pgoff_t)-1,
412 					PAGECACHE_TAG_DIRTY, &fbatch))) {
413 		int i;
414 
415 		for (i = 0; i < nr_folios; i++) {
416 			struct folio *folio = fbatch.folios[i];
417 
418 			if (nr_to_write != LONG_MAX && i != 0 &&
419 					folio->index != prev +
420 					folio_nr_pages(fbatch.folios[i-1])) {
421 				folio_batch_release(&fbatch);
422 				goto stop;
423 			}
424 
425 			folio_lock(folio);
426 
427 			if (unlikely(folio->mapping != mapping)) {
428 continue_unlock:
429 				folio_unlock(folio);
430 				continue;
431 			}
432 			if (!folio_test_dirty(folio)) {
433 				/* someone wrote it for us */
434 				goto continue_unlock;
435 			}
436 
437 			f2fs_wait_on_page_writeback(&folio->page, META,
438 					true, true);
439 
440 			if (!folio_clear_dirty_for_io(folio))
441 				goto continue_unlock;
442 
443 			if (__f2fs_write_meta_page(&folio->page, &wbc,
444 						io_type)) {
445 				folio_unlock(folio);
446 				break;
447 			}
448 			nwritten += folio_nr_pages(folio);
449 			prev = folio->index;
450 			if (unlikely(nwritten >= nr_to_write))
451 				break;
452 		}
453 		folio_batch_release(&fbatch);
454 		cond_resched();
455 	}
456 stop:
457 	if (nwritten)
458 		f2fs_submit_merged_write(sbi, type);
459 
460 	blk_finish_plug(&plug);
461 
462 	return nwritten;
463 }
464 
465 static bool f2fs_dirty_meta_folio(struct address_space *mapping,
466 		struct folio *folio)
467 {
468 	trace_f2fs_set_page_dirty(&folio->page, META);
469 
470 	if (!folio_test_uptodate(folio))
471 		folio_mark_uptodate(folio);
472 	if (filemap_dirty_folio(mapping, folio)) {
473 		inc_page_count(F2FS_M_SB(mapping), F2FS_DIRTY_META);
474 		set_page_private_reference(&folio->page);
475 		return true;
476 	}
477 	return false;
478 }
479 
480 const struct address_space_operations f2fs_meta_aops = {
481 	.writepage	= f2fs_write_meta_page,
482 	.writepages	= f2fs_write_meta_pages,
483 	.dirty_folio	= f2fs_dirty_meta_folio,
484 	.invalidate_folio = f2fs_invalidate_folio,
485 	.release_folio	= f2fs_release_folio,
486 	.migrate_folio	= filemap_migrate_folio,
487 };
488 
489 static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino,
490 						unsigned int devidx, int type)
491 {
492 	struct inode_management *im = &sbi->im[type];
493 	struct ino_entry *e = NULL, *new = NULL;
494 
495 	if (type == FLUSH_INO) {
496 		rcu_read_lock();
497 		e = radix_tree_lookup(&im->ino_root, ino);
498 		rcu_read_unlock();
499 	}
500 
501 retry:
502 	if (!e)
503 		new = f2fs_kmem_cache_alloc(ino_entry_slab,
504 						GFP_NOFS, true, NULL);
505 
506 	radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
507 
508 	spin_lock(&im->ino_lock);
509 	e = radix_tree_lookup(&im->ino_root, ino);
510 	if (!e) {
511 		if (!new) {
512 			spin_unlock(&im->ino_lock);
513 			goto retry;
514 		}
515 		e = new;
516 		if (unlikely(radix_tree_insert(&im->ino_root, ino, e)))
517 			f2fs_bug_on(sbi, 1);
518 
519 		memset(e, 0, sizeof(struct ino_entry));
520 		e->ino = ino;
521 
522 		list_add_tail(&e->list, &im->ino_list);
523 		if (type != ORPHAN_INO)
524 			im->ino_num++;
525 	}
526 
527 	if (type == FLUSH_INO)
528 		f2fs_set_bit(devidx, (char *)&e->dirty_device);
529 
530 	spin_unlock(&im->ino_lock);
531 	radix_tree_preload_end();
532 
533 	if (new && e != new)
534 		kmem_cache_free(ino_entry_slab, new);
535 }
536 
537 static void __remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
538 {
539 	struct inode_management *im = &sbi->im[type];
540 	struct ino_entry *e;
541 
542 	spin_lock(&im->ino_lock);
543 	e = radix_tree_lookup(&im->ino_root, ino);
544 	if (e) {
545 		list_del(&e->list);
546 		radix_tree_delete(&im->ino_root, ino);
547 		im->ino_num--;
548 		spin_unlock(&im->ino_lock);
549 		kmem_cache_free(ino_entry_slab, e);
550 		return;
551 	}
552 	spin_unlock(&im->ino_lock);
553 }
554 
555 void f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
556 {
557 	/* add new dirty ino entry into list */
558 	__add_ino_entry(sbi, ino, 0, type);
559 }
560 
561 void f2fs_remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
562 {
563 	/* remove dirty ino entry from list */
564 	__remove_ino_entry(sbi, ino, type);
565 }
566 
567 /* mode should be APPEND_INO, UPDATE_INO or TRANS_DIR_INO */
568 bool f2fs_exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode)
569 {
570 	struct inode_management *im = &sbi->im[mode];
571 	struct ino_entry *e;
572 
573 	spin_lock(&im->ino_lock);
574 	e = radix_tree_lookup(&im->ino_root, ino);
575 	spin_unlock(&im->ino_lock);
576 	return e ? true : false;
577 }
578 
579 void f2fs_release_ino_entry(struct f2fs_sb_info *sbi, bool all)
580 {
581 	struct ino_entry *e, *tmp;
582 	int i;
583 
584 	for (i = all ? ORPHAN_INO : APPEND_INO; i < MAX_INO_ENTRY; i++) {
585 		struct inode_management *im = &sbi->im[i];
586 
587 		spin_lock(&im->ino_lock);
588 		list_for_each_entry_safe(e, tmp, &im->ino_list, list) {
589 			list_del(&e->list);
590 			radix_tree_delete(&im->ino_root, e->ino);
591 			kmem_cache_free(ino_entry_slab, e);
592 			im->ino_num--;
593 		}
594 		spin_unlock(&im->ino_lock);
595 	}
596 }
597 
598 void f2fs_set_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
599 					unsigned int devidx, int type)
600 {
601 	__add_ino_entry(sbi, ino, devidx, type);
602 }
603 
604 bool f2fs_is_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
605 					unsigned int devidx, int type)
606 {
607 	struct inode_management *im = &sbi->im[type];
608 	struct ino_entry *e;
609 	bool is_dirty = false;
610 
611 	spin_lock(&im->ino_lock);
612 	e = radix_tree_lookup(&im->ino_root, ino);
613 	if (e && f2fs_test_bit(devidx, (char *)&e->dirty_device))
614 		is_dirty = true;
615 	spin_unlock(&im->ino_lock);
616 	return is_dirty;
617 }
618 
619 int f2fs_acquire_orphan_inode(struct f2fs_sb_info *sbi)
620 {
621 	struct inode_management *im = &sbi->im[ORPHAN_INO];
622 	int err = 0;
623 
624 	spin_lock(&im->ino_lock);
625 
626 	if (time_to_inject(sbi, FAULT_ORPHAN)) {
627 		spin_unlock(&im->ino_lock);
628 		f2fs_show_injection_info(sbi, FAULT_ORPHAN);
629 		return -ENOSPC;
630 	}
631 
632 	if (unlikely(im->ino_num >= sbi->max_orphans))
633 		err = -ENOSPC;
634 	else
635 		im->ino_num++;
636 	spin_unlock(&im->ino_lock);
637 
638 	return err;
639 }
640 
641 void f2fs_release_orphan_inode(struct f2fs_sb_info *sbi)
642 {
643 	struct inode_management *im = &sbi->im[ORPHAN_INO];
644 
645 	spin_lock(&im->ino_lock);
646 	f2fs_bug_on(sbi, im->ino_num == 0);
647 	im->ino_num--;
648 	spin_unlock(&im->ino_lock);
649 }
650 
651 void f2fs_add_orphan_inode(struct inode *inode)
652 {
653 	/* add new orphan ino entry into list */
654 	__add_ino_entry(F2FS_I_SB(inode), inode->i_ino, 0, ORPHAN_INO);
655 	f2fs_update_inode_page(inode);
656 }
657 
658 void f2fs_remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
659 {
660 	/* remove orphan entry from orphan list */
661 	__remove_ino_entry(sbi, ino, ORPHAN_INO);
662 }
663 
664 static int recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
665 {
666 	struct inode *inode;
667 	struct node_info ni;
668 	int err;
669 
670 	inode = f2fs_iget_retry(sbi->sb, ino);
671 	if (IS_ERR(inode)) {
672 		/*
673 		 * there should be a bug that we can't find the entry
674 		 * to orphan inode.
675 		 */
676 		f2fs_bug_on(sbi, PTR_ERR(inode) == -ENOENT);
677 		return PTR_ERR(inode);
678 	}
679 
680 	err = f2fs_dquot_initialize(inode);
681 	if (err) {
682 		iput(inode);
683 		goto err_out;
684 	}
685 
686 	clear_nlink(inode);
687 
688 	/* truncate all the data during iput */
689 	iput(inode);
690 
691 	err = f2fs_get_node_info(sbi, ino, &ni, false);
692 	if (err)
693 		goto err_out;
694 
695 	/* ENOMEM was fully retried in f2fs_evict_inode. */
696 	if (ni.blk_addr != NULL_ADDR) {
697 		err = -EIO;
698 		goto err_out;
699 	}
700 	return 0;
701 
702 err_out:
703 	set_sbi_flag(sbi, SBI_NEED_FSCK);
704 	f2fs_warn(sbi, "%s: orphan failed (ino=%x), run fsck to fix.",
705 		  __func__, ino);
706 	return err;
707 }
708 
709 int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi)
710 {
711 	block_t start_blk, orphan_blocks, i, j;
712 	unsigned int s_flags = sbi->sb->s_flags;
713 	int err = 0;
714 #ifdef CONFIG_QUOTA
715 	int quota_enabled;
716 #endif
717 
718 	if (!is_set_ckpt_flags(sbi, CP_ORPHAN_PRESENT_FLAG))
719 		return 0;
720 
721 	if (bdev_read_only(sbi->sb->s_bdev)) {
722 		f2fs_info(sbi, "write access unavailable, skipping orphan cleanup");
723 		return 0;
724 	}
725 
726 	if (s_flags & SB_RDONLY) {
727 		f2fs_info(sbi, "orphan cleanup on readonly fs");
728 		sbi->sb->s_flags &= ~SB_RDONLY;
729 	}
730 
731 #ifdef CONFIG_QUOTA
732 	/*
733 	 * Turn on quotas which were not enabled for read-only mounts if
734 	 * filesystem has quota feature, so that they are updated correctly.
735 	 */
736 	quota_enabled = f2fs_enable_quota_files(sbi, s_flags & SB_RDONLY);
737 #endif
738 
739 	start_blk = __start_cp_addr(sbi) + 1 + __cp_payload(sbi);
740 	orphan_blocks = __start_sum_addr(sbi) - 1 - __cp_payload(sbi);
741 
742 	f2fs_ra_meta_pages(sbi, start_blk, orphan_blocks, META_CP, true);
743 
744 	for (i = 0; i < orphan_blocks; i++) {
745 		struct page *page;
746 		struct f2fs_orphan_block *orphan_blk;
747 
748 		page = f2fs_get_meta_page(sbi, start_blk + i);
749 		if (IS_ERR(page)) {
750 			err = PTR_ERR(page);
751 			goto out;
752 		}
753 
754 		orphan_blk = (struct f2fs_orphan_block *)page_address(page);
755 		for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
756 			nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
757 
758 			err = recover_orphan_inode(sbi, ino);
759 			if (err) {
760 				f2fs_put_page(page, 1);
761 				goto out;
762 			}
763 		}
764 		f2fs_put_page(page, 1);
765 	}
766 	/* clear Orphan Flag */
767 	clear_ckpt_flags(sbi, CP_ORPHAN_PRESENT_FLAG);
768 out:
769 	set_sbi_flag(sbi, SBI_IS_RECOVERED);
770 
771 #ifdef CONFIG_QUOTA
772 	/* Turn quotas off */
773 	if (quota_enabled)
774 		f2fs_quota_off_umount(sbi->sb);
775 #endif
776 	sbi->sb->s_flags = s_flags; /* Restore SB_RDONLY status */
777 
778 	return err;
779 }
780 
781 static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
782 {
783 	struct list_head *head;
784 	struct f2fs_orphan_block *orphan_blk = NULL;
785 	unsigned int nentries = 0;
786 	unsigned short index = 1;
787 	unsigned short orphan_blocks;
788 	struct page *page = NULL;
789 	struct ino_entry *orphan = NULL;
790 	struct inode_management *im = &sbi->im[ORPHAN_INO];
791 
792 	orphan_blocks = GET_ORPHAN_BLOCKS(im->ino_num);
793 
794 	/*
795 	 * we don't need to do spin_lock(&im->ino_lock) here, since all the
796 	 * orphan inode operations are covered under f2fs_lock_op().
797 	 * And, spin_lock should be avoided due to page operations below.
798 	 */
799 	head = &im->ino_list;
800 
801 	/* loop for each orphan inode entry and write them in Jornal block */
802 	list_for_each_entry(orphan, head, list) {
803 		if (!page) {
804 			page = f2fs_grab_meta_page(sbi, start_blk++);
805 			orphan_blk =
806 				(struct f2fs_orphan_block *)page_address(page);
807 			memset(orphan_blk, 0, sizeof(*orphan_blk));
808 		}
809 
810 		orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
811 
812 		if (nentries == F2FS_ORPHANS_PER_BLOCK) {
813 			/*
814 			 * an orphan block is full of 1020 entries,
815 			 * then we need to flush current orphan blocks
816 			 * and bring another one in memory
817 			 */
818 			orphan_blk->blk_addr = cpu_to_le16(index);
819 			orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
820 			orphan_blk->entry_count = cpu_to_le32(nentries);
821 			set_page_dirty(page);
822 			f2fs_put_page(page, 1);
823 			index++;
824 			nentries = 0;
825 			page = NULL;
826 		}
827 	}
828 
829 	if (page) {
830 		orphan_blk->blk_addr = cpu_to_le16(index);
831 		orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
832 		orphan_blk->entry_count = cpu_to_le32(nentries);
833 		set_page_dirty(page);
834 		f2fs_put_page(page, 1);
835 	}
836 }
837 
838 static __u32 f2fs_checkpoint_chksum(struct f2fs_sb_info *sbi,
839 						struct f2fs_checkpoint *ckpt)
840 {
841 	unsigned int chksum_ofs = le32_to_cpu(ckpt->checksum_offset);
842 	__u32 chksum;
843 
844 	chksum = f2fs_crc32(sbi, ckpt, chksum_ofs);
845 	if (chksum_ofs < CP_CHKSUM_OFFSET) {
846 		chksum_ofs += sizeof(chksum);
847 		chksum = f2fs_chksum(sbi, chksum, (__u8 *)ckpt + chksum_ofs,
848 						F2FS_BLKSIZE - chksum_ofs);
849 	}
850 	return chksum;
851 }
852 
853 static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
854 		struct f2fs_checkpoint **cp_block, struct page **cp_page,
855 		unsigned long long *version)
856 {
857 	size_t crc_offset = 0;
858 	__u32 crc;
859 
860 	*cp_page = f2fs_get_meta_page(sbi, cp_addr);
861 	if (IS_ERR(*cp_page))
862 		return PTR_ERR(*cp_page);
863 
864 	*cp_block = (struct f2fs_checkpoint *)page_address(*cp_page);
865 
866 	crc_offset = le32_to_cpu((*cp_block)->checksum_offset);
867 	if (crc_offset < CP_MIN_CHKSUM_OFFSET ||
868 			crc_offset > CP_CHKSUM_OFFSET) {
869 		f2fs_put_page(*cp_page, 1);
870 		f2fs_warn(sbi, "invalid crc_offset: %zu", crc_offset);
871 		return -EINVAL;
872 	}
873 
874 	crc = f2fs_checkpoint_chksum(sbi, *cp_block);
875 	if (crc != cur_cp_crc(*cp_block)) {
876 		f2fs_put_page(*cp_page, 1);
877 		f2fs_warn(sbi, "invalid crc value");
878 		return -EINVAL;
879 	}
880 
881 	*version = cur_cp_version(*cp_block);
882 	return 0;
883 }
884 
885 static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
886 				block_t cp_addr, unsigned long long *version)
887 {
888 	struct page *cp_page_1 = NULL, *cp_page_2 = NULL;
889 	struct f2fs_checkpoint *cp_block = NULL;
890 	unsigned long long cur_version = 0, pre_version = 0;
891 	unsigned int cp_blocks;
892 	int err;
893 
894 	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
895 					&cp_page_1, version);
896 	if (err)
897 		return NULL;
898 
899 	cp_blocks = le32_to_cpu(cp_block->cp_pack_total_block_count);
900 
901 	if (cp_blocks > sbi->blocks_per_seg || cp_blocks <= F2FS_CP_PACKS) {
902 		f2fs_warn(sbi, "invalid cp_pack_total_block_count:%u",
903 			  le32_to_cpu(cp_block->cp_pack_total_block_count));
904 		goto invalid_cp;
905 	}
906 	pre_version = *version;
907 
908 	cp_addr += cp_blocks - 1;
909 	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
910 					&cp_page_2, version);
911 	if (err)
912 		goto invalid_cp;
913 	cur_version = *version;
914 
915 	if (cur_version == pre_version) {
916 		*version = cur_version;
917 		f2fs_put_page(cp_page_2, 1);
918 		return cp_page_1;
919 	}
920 	f2fs_put_page(cp_page_2, 1);
921 invalid_cp:
922 	f2fs_put_page(cp_page_1, 1);
923 	return NULL;
924 }
925 
926 int f2fs_get_valid_checkpoint(struct f2fs_sb_info *sbi)
927 {
928 	struct f2fs_checkpoint *cp_block;
929 	struct f2fs_super_block *fsb = sbi->raw_super;
930 	struct page *cp1, *cp2, *cur_page;
931 	unsigned long blk_size = sbi->blocksize;
932 	unsigned long long cp1_version = 0, cp2_version = 0;
933 	unsigned long long cp_start_blk_no;
934 	unsigned int cp_blks = 1 + __cp_payload(sbi);
935 	block_t cp_blk_no;
936 	int i;
937 	int err;
938 
939 	sbi->ckpt = f2fs_kvzalloc(sbi, array_size(blk_size, cp_blks),
940 				  GFP_KERNEL);
941 	if (!sbi->ckpt)
942 		return -ENOMEM;
943 	/*
944 	 * Finding out valid cp block involves read both
945 	 * sets( cp pack 1 and cp pack 2)
946 	 */
947 	cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
948 	cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
949 
950 	/* The second checkpoint pack should start at the next segment */
951 	cp_start_blk_no += ((unsigned long long)1) <<
952 				le32_to_cpu(fsb->log_blocks_per_seg);
953 	cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
954 
955 	if (cp1 && cp2) {
956 		if (ver_after(cp2_version, cp1_version))
957 			cur_page = cp2;
958 		else
959 			cur_page = cp1;
960 	} else if (cp1) {
961 		cur_page = cp1;
962 	} else if (cp2) {
963 		cur_page = cp2;
964 	} else {
965 		err = -EFSCORRUPTED;
966 		goto fail_no_cp;
967 	}
968 
969 	cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
970 	memcpy(sbi->ckpt, cp_block, blk_size);
971 
972 	if (cur_page == cp1)
973 		sbi->cur_cp_pack = 1;
974 	else
975 		sbi->cur_cp_pack = 2;
976 
977 	/* Sanity checking of checkpoint */
978 	if (f2fs_sanity_check_ckpt(sbi)) {
979 		err = -EFSCORRUPTED;
980 		goto free_fail_no_cp;
981 	}
982 
983 	if (cp_blks <= 1)
984 		goto done;
985 
986 	cp_blk_no = le32_to_cpu(fsb->cp_blkaddr);
987 	if (cur_page == cp2)
988 		cp_blk_no += 1 << le32_to_cpu(fsb->log_blocks_per_seg);
989 
990 	for (i = 1; i < cp_blks; i++) {
991 		void *sit_bitmap_ptr;
992 		unsigned char *ckpt = (unsigned char *)sbi->ckpt;
993 
994 		cur_page = f2fs_get_meta_page(sbi, cp_blk_no + i);
995 		if (IS_ERR(cur_page)) {
996 			err = PTR_ERR(cur_page);
997 			goto free_fail_no_cp;
998 		}
999 		sit_bitmap_ptr = page_address(cur_page);
1000 		memcpy(ckpt + i * blk_size, sit_bitmap_ptr, blk_size);
1001 		f2fs_put_page(cur_page, 1);
1002 	}
1003 done:
1004 	f2fs_put_page(cp1, 1);
1005 	f2fs_put_page(cp2, 1);
1006 	return 0;
1007 
1008 free_fail_no_cp:
1009 	f2fs_put_page(cp1, 1);
1010 	f2fs_put_page(cp2, 1);
1011 fail_no_cp:
1012 	kvfree(sbi->ckpt);
1013 	return err;
1014 }
1015 
1016 static void __add_dirty_inode(struct inode *inode, enum inode_type type)
1017 {
1018 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1019 	int flag = (type == DIR_INODE) ? FI_DIRTY_DIR : FI_DIRTY_FILE;
1020 
1021 	if (is_inode_flag_set(inode, flag))
1022 		return;
1023 
1024 	set_inode_flag(inode, flag);
1025 	list_add_tail(&F2FS_I(inode)->dirty_list, &sbi->inode_list[type]);
1026 	stat_inc_dirty_inode(sbi, type);
1027 }
1028 
1029 static void __remove_dirty_inode(struct inode *inode, enum inode_type type)
1030 {
1031 	int flag = (type == DIR_INODE) ? FI_DIRTY_DIR : FI_DIRTY_FILE;
1032 
1033 	if (get_dirty_pages(inode) || !is_inode_flag_set(inode, flag))
1034 		return;
1035 
1036 	list_del_init(&F2FS_I(inode)->dirty_list);
1037 	clear_inode_flag(inode, flag);
1038 	stat_dec_dirty_inode(F2FS_I_SB(inode), type);
1039 }
1040 
1041 void f2fs_update_dirty_folio(struct inode *inode, struct folio *folio)
1042 {
1043 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1044 	enum inode_type type = S_ISDIR(inode->i_mode) ? DIR_INODE : FILE_INODE;
1045 
1046 	if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
1047 			!S_ISLNK(inode->i_mode))
1048 		return;
1049 
1050 	spin_lock(&sbi->inode_lock[type]);
1051 	if (type != FILE_INODE || test_opt(sbi, DATA_FLUSH))
1052 		__add_dirty_inode(inode, type);
1053 	inode_inc_dirty_pages(inode);
1054 	spin_unlock(&sbi->inode_lock[type]);
1055 
1056 	set_page_private_reference(&folio->page);
1057 }
1058 
1059 void f2fs_remove_dirty_inode(struct inode *inode)
1060 {
1061 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1062 	enum inode_type type = S_ISDIR(inode->i_mode) ? DIR_INODE : FILE_INODE;
1063 
1064 	if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
1065 			!S_ISLNK(inode->i_mode))
1066 		return;
1067 
1068 	if (type == FILE_INODE && !test_opt(sbi, DATA_FLUSH))
1069 		return;
1070 
1071 	spin_lock(&sbi->inode_lock[type]);
1072 	__remove_dirty_inode(inode, type);
1073 	spin_unlock(&sbi->inode_lock[type]);
1074 }
1075 
1076 int f2fs_sync_dirty_inodes(struct f2fs_sb_info *sbi, enum inode_type type,
1077 						bool from_cp)
1078 {
1079 	struct list_head *head;
1080 	struct inode *inode;
1081 	struct f2fs_inode_info *fi;
1082 	bool is_dir = (type == DIR_INODE);
1083 	unsigned long ino = 0;
1084 
1085 	trace_f2fs_sync_dirty_inodes_enter(sbi->sb, is_dir,
1086 				get_pages(sbi, is_dir ?
1087 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1088 retry:
1089 	if (unlikely(f2fs_cp_error(sbi))) {
1090 		trace_f2fs_sync_dirty_inodes_exit(sbi->sb, is_dir,
1091 				get_pages(sbi, is_dir ?
1092 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1093 		return -EIO;
1094 	}
1095 
1096 	spin_lock(&sbi->inode_lock[type]);
1097 
1098 	head = &sbi->inode_list[type];
1099 	if (list_empty(head)) {
1100 		spin_unlock(&sbi->inode_lock[type]);
1101 		trace_f2fs_sync_dirty_inodes_exit(sbi->sb, is_dir,
1102 				get_pages(sbi, is_dir ?
1103 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1104 		return 0;
1105 	}
1106 	fi = list_first_entry(head, struct f2fs_inode_info, dirty_list);
1107 	inode = igrab(&fi->vfs_inode);
1108 	spin_unlock(&sbi->inode_lock[type]);
1109 	if (inode) {
1110 		unsigned long cur_ino = inode->i_ino;
1111 
1112 		if (from_cp)
1113 			F2FS_I(inode)->cp_task = current;
1114 		F2FS_I(inode)->wb_task = current;
1115 
1116 		filemap_fdatawrite(inode->i_mapping);
1117 
1118 		F2FS_I(inode)->wb_task = NULL;
1119 		if (from_cp)
1120 			F2FS_I(inode)->cp_task = NULL;
1121 
1122 		iput(inode);
1123 		/* We need to give cpu to another writers. */
1124 		if (ino == cur_ino)
1125 			cond_resched();
1126 		else
1127 			ino = cur_ino;
1128 	} else {
1129 		/*
1130 		 * We should submit bio, since it exists several
1131 		 * wribacking dentry pages in the freeing inode.
1132 		 */
1133 		f2fs_submit_merged_write(sbi, DATA);
1134 		cond_resched();
1135 	}
1136 	goto retry;
1137 }
1138 
1139 int f2fs_sync_inode_meta(struct f2fs_sb_info *sbi)
1140 {
1141 	struct list_head *head = &sbi->inode_list[DIRTY_META];
1142 	struct inode *inode;
1143 	struct f2fs_inode_info *fi;
1144 	s64 total = get_pages(sbi, F2FS_DIRTY_IMETA);
1145 
1146 	while (total--) {
1147 		if (unlikely(f2fs_cp_error(sbi)))
1148 			return -EIO;
1149 
1150 		spin_lock(&sbi->inode_lock[DIRTY_META]);
1151 		if (list_empty(head)) {
1152 			spin_unlock(&sbi->inode_lock[DIRTY_META]);
1153 			return 0;
1154 		}
1155 		fi = list_first_entry(head, struct f2fs_inode_info,
1156 							gdirty_list);
1157 		inode = igrab(&fi->vfs_inode);
1158 		spin_unlock(&sbi->inode_lock[DIRTY_META]);
1159 		if (inode) {
1160 			sync_inode_metadata(inode, 0);
1161 
1162 			/* it's on eviction */
1163 			if (is_inode_flag_set(inode, FI_DIRTY_INODE))
1164 				f2fs_update_inode_page(inode);
1165 			iput(inode);
1166 		}
1167 	}
1168 	return 0;
1169 }
1170 
1171 static void __prepare_cp_block(struct f2fs_sb_info *sbi)
1172 {
1173 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1174 	struct f2fs_nm_info *nm_i = NM_I(sbi);
1175 	nid_t last_nid = nm_i->next_scan_nid;
1176 
1177 	next_free_nid(sbi, &last_nid);
1178 	ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
1179 	ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
1180 	ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
1181 	ckpt->next_free_nid = cpu_to_le32(last_nid);
1182 }
1183 
1184 static bool __need_flush_quota(struct f2fs_sb_info *sbi)
1185 {
1186 	bool ret = false;
1187 
1188 	if (!is_journalled_quota(sbi))
1189 		return false;
1190 
1191 	if (!f2fs_down_write_trylock(&sbi->quota_sem))
1192 		return true;
1193 	if (is_sbi_flag_set(sbi, SBI_QUOTA_SKIP_FLUSH)) {
1194 		ret = false;
1195 	} else if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_REPAIR)) {
1196 		ret = false;
1197 	} else if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_FLUSH)) {
1198 		clear_sbi_flag(sbi, SBI_QUOTA_NEED_FLUSH);
1199 		ret = true;
1200 	} else if (get_pages(sbi, F2FS_DIRTY_QDATA)) {
1201 		ret = true;
1202 	}
1203 	f2fs_up_write(&sbi->quota_sem);
1204 	return ret;
1205 }
1206 
1207 /*
1208  * Freeze all the FS-operations for checkpoint.
1209  */
1210 static int block_operations(struct f2fs_sb_info *sbi)
1211 {
1212 	struct writeback_control wbc = {
1213 		.sync_mode = WB_SYNC_ALL,
1214 		.nr_to_write = LONG_MAX,
1215 		.for_reclaim = 0,
1216 	};
1217 	int err = 0, cnt = 0;
1218 
1219 	/*
1220 	 * Let's flush inline_data in dirty node pages.
1221 	 */
1222 	f2fs_flush_inline_data(sbi);
1223 
1224 retry_flush_quotas:
1225 	f2fs_lock_all(sbi);
1226 	if (__need_flush_quota(sbi)) {
1227 		int locked;
1228 
1229 		if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) {
1230 			set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH);
1231 			set_sbi_flag(sbi, SBI_QUOTA_NEED_FLUSH);
1232 			goto retry_flush_dents;
1233 		}
1234 		f2fs_unlock_all(sbi);
1235 
1236 		/* only failed during mount/umount/freeze/quotactl */
1237 		locked = down_read_trylock(&sbi->sb->s_umount);
1238 		f2fs_quota_sync(sbi->sb, -1);
1239 		if (locked)
1240 			up_read(&sbi->sb->s_umount);
1241 		cond_resched();
1242 		goto retry_flush_quotas;
1243 	}
1244 
1245 retry_flush_dents:
1246 	/* write all the dirty dentry pages */
1247 	if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
1248 		f2fs_unlock_all(sbi);
1249 		err = f2fs_sync_dirty_inodes(sbi, DIR_INODE, true);
1250 		if (err)
1251 			return err;
1252 		cond_resched();
1253 		goto retry_flush_quotas;
1254 	}
1255 
1256 	/*
1257 	 * POR: we should ensure that there are no dirty node pages
1258 	 * until finishing nat/sit flush. inode->i_blocks can be updated.
1259 	 */
1260 	f2fs_down_write(&sbi->node_change);
1261 
1262 	if (get_pages(sbi, F2FS_DIRTY_IMETA)) {
1263 		f2fs_up_write(&sbi->node_change);
1264 		f2fs_unlock_all(sbi);
1265 		err = f2fs_sync_inode_meta(sbi);
1266 		if (err)
1267 			return err;
1268 		cond_resched();
1269 		goto retry_flush_quotas;
1270 	}
1271 
1272 retry_flush_nodes:
1273 	f2fs_down_write(&sbi->node_write);
1274 
1275 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
1276 		f2fs_up_write(&sbi->node_write);
1277 		atomic_inc(&sbi->wb_sync_req[NODE]);
1278 		err = f2fs_sync_node_pages(sbi, &wbc, false, FS_CP_NODE_IO);
1279 		atomic_dec(&sbi->wb_sync_req[NODE]);
1280 		if (err) {
1281 			f2fs_up_write(&sbi->node_change);
1282 			f2fs_unlock_all(sbi);
1283 			return err;
1284 		}
1285 		cond_resched();
1286 		goto retry_flush_nodes;
1287 	}
1288 
1289 	/*
1290 	 * sbi->node_change is used only for AIO write_begin path which produces
1291 	 * dirty node blocks and some checkpoint values by block allocation.
1292 	 */
1293 	__prepare_cp_block(sbi);
1294 	f2fs_up_write(&sbi->node_change);
1295 	return err;
1296 }
1297 
1298 static void unblock_operations(struct f2fs_sb_info *sbi)
1299 {
1300 	f2fs_up_write(&sbi->node_write);
1301 	f2fs_unlock_all(sbi);
1302 }
1303 
1304 void f2fs_wait_on_all_pages(struct f2fs_sb_info *sbi, int type)
1305 {
1306 	DEFINE_WAIT(wait);
1307 
1308 	for (;;) {
1309 		if (!get_pages(sbi, type))
1310 			break;
1311 
1312 		if (unlikely(f2fs_cp_error(sbi)))
1313 			break;
1314 
1315 		if (type == F2FS_DIRTY_META)
1316 			f2fs_sync_meta_pages(sbi, META, LONG_MAX,
1317 							FS_CP_META_IO);
1318 		else if (type == F2FS_WB_CP_DATA)
1319 			f2fs_submit_merged_write(sbi, DATA);
1320 
1321 		prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
1322 		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
1323 	}
1324 	finish_wait(&sbi->cp_wait, &wait);
1325 }
1326 
1327 static void update_ckpt_flags(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1328 {
1329 	unsigned long orphan_num = sbi->im[ORPHAN_INO].ino_num;
1330 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1331 	unsigned long flags;
1332 
1333 	if (cpc->reason & CP_UMOUNT) {
1334 		if (le32_to_cpu(ckpt->cp_pack_total_block_count) +
1335 			NM_I(sbi)->nat_bits_blocks > sbi->blocks_per_seg) {
1336 			clear_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
1337 			f2fs_notice(sbi, "Disable nat_bits due to no space");
1338 		} else if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG) &&
1339 						f2fs_nat_bitmap_enabled(sbi)) {
1340 			f2fs_enable_nat_bits(sbi);
1341 			set_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
1342 			f2fs_notice(sbi, "Rebuild and enable nat_bits");
1343 		}
1344 	}
1345 
1346 	spin_lock_irqsave(&sbi->cp_lock, flags);
1347 
1348 	if (cpc->reason & CP_TRIMMED)
1349 		__set_ckpt_flags(ckpt, CP_TRIMMED_FLAG);
1350 	else
1351 		__clear_ckpt_flags(ckpt, CP_TRIMMED_FLAG);
1352 
1353 	if (cpc->reason & CP_UMOUNT)
1354 		__set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
1355 	else
1356 		__clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
1357 
1358 	if (cpc->reason & CP_FASTBOOT)
1359 		__set_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
1360 	else
1361 		__clear_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
1362 
1363 	if (orphan_num)
1364 		__set_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
1365 	else
1366 		__clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
1367 
1368 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
1369 		__set_ckpt_flags(ckpt, CP_FSCK_FLAG);
1370 
1371 	if (is_sbi_flag_set(sbi, SBI_IS_RESIZEFS))
1372 		__set_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
1373 	else
1374 		__clear_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
1375 
1376 	if (is_sbi_flag_set(sbi, SBI_CP_DISABLED))
1377 		__set_ckpt_flags(ckpt, CP_DISABLED_FLAG);
1378 	else
1379 		__clear_ckpt_flags(ckpt, CP_DISABLED_FLAG);
1380 
1381 	if (is_sbi_flag_set(sbi, SBI_CP_DISABLED_QUICK))
1382 		__set_ckpt_flags(ckpt, CP_DISABLED_QUICK_FLAG);
1383 	else
1384 		__clear_ckpt_flags(ckpt, CP_DISABLED_QUICK_FLAG);
1385 
1386 	if (is_sbi_flag_set(sbi, SBI_QUOTA_SKIP_FLUSH))
1387 		__set_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1388 	else
1389 		__clear_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1390 
1391 	if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_REPAIR))
1392 		__set_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1393 
1394 	/* set this flag to activate crc|cp_ver for recovery */
1395 	__set_ckpt_flags(ckpt, CP_CRC_RECOVERY_FLAG);
1396 	__clear_ckpt_flags(ckpt, CP_NOCRC_RECOVERY_FLAG);
1397 
1398 	spin_unlock_irqrestore(&sbi->cp_lock, flags);
1399 }
1400 
1401 static void commit_checkpoint(struct f2fs_sb_info *sbi,
1402 	void *src, block_t blk_addr)
1403 {
1404 	struct writeback_control wbc = {
1405 		.for_reclaim = 0,
1406 	};
1407 
1408 	/*
1409 	 * filemap_get_folios_tag and lock_page again will take
1410 	 * some extra time. Therefore, f2fs_update_meta_pages and
1411 	 * f2fs_sync_meta_pages are combined in this function.
1412 	 */
1413 	struct page *page = f2fs_grab_meta_page(sbi, blk_addr);
1414 	int err;
1415 
1416 	f2fs_wait_on_page_writeback(page, META, true, true);
1417 
1418 	memcpy(page_address(page), src, PAGE_SIZE);
1419 
1420 	set_page_dirty(page);
1421 	if (unlikely(!clear_page_dirty_for_io(page)))
1422 		f2fs_bug_on(sbi, 1);
1423 
1424 	/* writeout cp pack 2 page */
1425 	err = __f2fs_write_meta_page(page, &wbc, FS_CP_META_IO);
1426 	if (unlikely(err && f2fs_cp_error(sbi))) {
1427 		f2fs_put_page(page, 1);
1428 		return;
1429 	}
1430 
1431 	f2fs_bug_on(sbi, err);
1432 	f2fs_put_page(page, 0);
1433 
1434 	/* submit checkpoint (with barrier if NOBARRIER is not set) */
1435 	f2fs_submit_merged_write(sbi, META_FLUSH);
1436 }
1437 
1438 static inline u64 get_sectors_written(struct block_device *bdev)
1439 {
1440 	return (u64)part_stat_read(bdev, sectors[STAT_WRITE]);
1441 }
1442 
1443 u64 f2fs_get_sectors_written(struct f2fs_sb_info *sbi)
1444 {
1445 	if (f2fs_is_multi_device(sbi)) {
1446 		u64 sectors = 0;
1447 		int i;
1448 
1449 		for (i = 0; i < sbi->s_ndevs; i++)
1450 			sectors += get_sectors_written(FDEV(i).bdev);
1451 
1452 		return sectors;
1453 	}
1454 
1455 	return get_sectors_written(sbi->sb->s_bdev);
1456 }
1457 
1458 static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1459 {
1460 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1461 	struct f2fs_nm_info *nm_i = NM_I(sbi);
1462 	unsigned long orphan_num = sbi->im[ORPHAN_INO].ino_num, flags;
1463 	block_t start_blk;
1464 	unsigned int data_sum_blocks, orphan_blocks;
1465 	__u32 crc32 = 0;
1466 	int i;
1467 	int cp_payload_blks = __cp_payload(sbi);
1468 	struct curseg_info *seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
1469 	u64 kbytes_written;
1470 	int err;
1471 
1472 	/* Flush all the NAT/SIT pages */
1473 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
1474 
1475 	/* start to update checkpoint, cp ver is already updated previously */
1476 	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi, true));
1477 	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
1478 	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
1479 		ckpt->cur_node_segno[i] =
1480 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
1481 		ckpt->cur_node_blkoff[i] =
1482 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
1483 		ckpt->alloc_type[i + CURSEG_HOT_NODE] =
1484 				curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
1485 	}
1486 	for (i = 0; i < NR_CURSEG_DATA_TYPE; i++) {
1487 		ckpt->cur_data_segno[i] =
1488 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
1489 		ckpt->cur_data_blkoff[i] =
1490 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
1491 		ckpt->alloc_type[i + CURSEG_HOT_DATA] =
1492 				curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
1493 	}
1494 
1495 	/* 2 cp + n data seg summary + orphan inode blocks */
1496 	data_sum_blocks = f2fs_npages_for_summary_flush(sbi, false);
1497 	spin_lock_irqsave(&sbi->cp_lock, flags);
1498 	if (data_sum_blocks < NR_CURSEG_DATA_TYPE)
1499 		__set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
1500 	else
1501 		__clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
1502 	spin_unlock_irqrestore(&sbi->cp_lock, flags);
1503 
1504 	orphan_blocks = GET_ORPHAN_BLOCKS(orphan_num);
1505 	ckpt->cp_pack_start_sum = cpu_to_le32(1 + cp_payload_blks +
1506 			orphan_blocks);
1507 
1508 	if (__remain_node_summaries(cpc->reason))
1509 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS +
1510 				cp_payload_blks + data_sum_blocks +
1511 				orphan_blocks + NR_CURSEG_NODE_TYPE);
1512 	else
1513 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS +
1514 				cp_payload_blks + data_sum_blocks +
1515 				orphan_blocks);
1516 
1517 	/* update ckpt flag for checkpoint */
1518 	update_ckpt_flags(sbi, cpc);
1519 
1520 	/* update SIT/NAT bitmap */
1521 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
1522 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
1523 
1524 	crc32 = f2fs_checkpoint_chksum(sbi, ckpt);
1525 	*((__le32 *)((unsigned char *)ckpt +
1526 				le32_to_cpu(ckpt->checksum_offset)))
1527 				= cpu_to_le32(crc32);
1528 
1529 	start_blk = __start_cp_next_addr(sbi);
1530 
1531 	/* write nat bits */
1532 	if ((cpc->reason & CP_UMOUNT) &&
1533 			is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG)) {
1534 		__u64 cp_ver = cur_cp_version(ckpt);
1535 		block_t blk;
1536 
1537 		cp_ver |= ((__u64)crc32 << 32);
1538 		*(__le64 *)nm_i->nat_bits = cpu_to_le64(cp_ver);
1539 
1540 		blk = start_blk + sbi->blocks_per_seg - nm_i->nat_bits_blocks;
1541 		for (i = 0; i < nm_i->nat_bits_blocks; i++)
1542 			f2fs_update_meta_page(sbi, nm_i->nat_bits +
1543 					(i << F2FS_BLKSIZE_BITS), blk + i);
1544 	}
1545 
1546 	/* write out checkpoint buffer at block 0 */
1547 	f2fs_update_meta_page(sbi, ckpt, start_blk++);
1548 
1549 	for (i = 1; i < 1 + cp_payload_blks; i++)
1550 		f2fs_update_meta_page(sbi, (char *)ckpt + i * F2FS_BLKSIZE,
1551 							start_blk++);
1552 
1553 	if (orphan_num) {
1554 		write_orphan_inodes(sbi, start_blk);
1555 		start_blk += orphan_blocks;
1556 	}
1557 
1558 	f2fs_write_data_summaries(sbi, start_blk);
1559 	start_blk += data_sum_blocks;
1560 
1561 	/* Record write statistics in the hot node summary */
1562 	kbytes_written = sbi->kbytes_written;
1563 	kbytes_written += (f2fs_get_sectors_written(sbi) -
1564 				sbi->sectors_written_start) >> 1;
1565 	seg_i->journal->info.kbytes_written = cpu_to_le64(kbytes_written);
1566 
1567 	if (__remain_node_summaries(cpc->reason)) {
1568 		f2fs_write_node_summaries(sbi, start_blk);
1569 		start_blk += NR_CURSEG_NODE_TYPE;
1570 	}
1571 
1572 	/* update user_block_counts */
1573 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1574 	percpu_counter_set(&sbi->alloc_valid_block_count, 0);
1575 	percpu_counter_set(&sbi->rf_node_block_count, 0);
1576 
1577 	/* Here, we have one bio having CP pack except cp pack 2 page */
1578 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
1579 	/* Wait for all dirty meta pages to be submitted for IO */
1580 	f2fs_wait_on_all_pages(sbi, F2FS_DIRTY_META);
1581 
1582 	/* wait for previous submitted meta pages writeback */
1583 	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
1584 
1585 	/* flush all device cache */
1586 	err = f2fs_flush_device_cache(sbi);
1587 	if (err)
1588 		return err;
1589 
1590 	/* barrier and flush checkpoint cp pack 2 page if it can */
1591 	commit_checkpoint(sbi, ckpt, start_blk);
1592 	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
1593 
1594 	/*
1595 	 * invalidate intermediate page cache borrowed from meta inode which are
1596 	 * used for migration of encrypted, verity or compressed inode's blocks.
1597 	 */
1598 	if (f2fs_sb_has_encrypt(sbi) || f2fs_sb_has_verity(sbi) ||
1599 		f2fs_sb_has_compression(sbi))
1600 		invalidate_mapping_pages(META_MAPPING(sbi),
1601 				MAIN_BLKADDR(sbi), MAX_BLKADDR(sbi) - 1);
1602 
1603 	f2fs_release_ino_entry(sbi, false);
1604 
1605 	f2fs_reset_fsync_node_info(sbi);
1606 
1607 	clear_sbi_flag(sbi, SBI_IS_DIRTY);
1608 	clear_sbi_flag(sbi, SBI_NEED_CP);
1609 	clear_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH);
1610 
1611 	spin_lock(&sbi->stat_lock);
1612 	sbi->unusable_block_count = 0;
1613 	spin_unlock(&sbi->stat_lock);
1614 
1615 	__set_cp_next_pack(sbi);
1616 
1617 	/*
1618 	 * redirty superblock if metadata like node page or inode cache is
1619 	 * updated during writing checkpoint.
1620 	 */
1621 	if (get_pages(sbi, F2FS_DIRTY_NODES) ||
1622 			get_pages(sbi, F2FS_DIRTY_IMETA))
1623 		set_sbi_flag(sbi, SBI_IS_DIRTY);
1624 
1625 	f2fs_bug_on(sbi, get_pages(sbi, F2FS_DIRTY_DENTS));
1626 
1627 	return unlikely(f2fs_cp_error(sbi)) ? -EIO : 0;
1628 }
1629 
1630 int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1631 {
1632 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1633 	unsigned long long ckpt_ver;
1634 	int err = 0;
1635 
1636 	if (f2fs_readonly(sbi->sb) || f2fs_hw_is_readonly(sbi))
1637 		return -EROFS;
1638 
1639 	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) {
1640 		if (cpc->reason != CP_PAUSE)
1641 			return 0;
1642 		f2fs_warn(sbi, "Start checkpoint disabled!");
1643 	}
1644 	if (cpc->reason != CP_RESIZE)
1645 		f2fs_down_write(&sbi->cp_global_sem);
1646 
1647 	if (!is_sbi_flag_set(sbi, SBI_IS_DIRTY) &&
1648 		((cpc->reason & CP_FASTBOOT) || (cpc->reason & CP_SYNC) ||
1649 		((cpc->reason & CP_DISCARD) && !sbi->discard_blks)))
1650 		goto out;
1651 	if (unlikely(f2fs_cp_error(sbi))) {
1652 		err = -EIO;
1653 		goto out;
1654 	}
1655 
1656 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "start block_ops");
1657 
1658 	err = block_operations(sbi);
1659 	if (err)
1660 		goto out;
1661 
1662 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish block_ops");
1663 
1664 	f2fs_flush_merged_writes(sbi);
1665 
1666 	/* this is the case of multiple fstrims without any changes */
1667 	if (cpc->reason & CP_DISCARD) {
1668 		if (!f2fs_exist_trim_candidates(sbi, cpc)) {
1669 			unblock_operations(sbi);
1670 			goto out;
1671 		}
1672 
1673 		if (NM_I(sbi)->nat_cnt[DIRTY_NAT] == 0 &&
1674 				SIT_I(sbi)->dirty_sentries == 0 &&
1675 				prefree_segments(sbi) == 0) {
1676 			f2fs_flush_sit_entries(sbi, cpc);
1677 			f2fs_clear_prefree_segments(sbi, cpc);
1678 			unblock_operations(sbi);
1679 			goto out;
1680 		}
1681 	}
1682 
1683 	/*
1684 	 * update checkpoint pack index
1685 	 * Increase the version number so that
1686 	 * SIT entries and seg summaries are written at correct place
1687 	 */
1688 	ckpt_ver = cur_cp_version(ckpt);
1689 	ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
1690 
1691 	/* write cached NAT/SIT entries to NAT/SIT area */
1692 	err = f2fs_flush_nat_entries(sbi, cpc);
1693 	if (err) {
1694 		f2fs_err(sbi, "f2fs_flush_nat_entries failed err:%d, stop checkpoint", err);
1695 		f2fs_bug_on(sbi, !f2fs_cp_error(sbi));
1696 		goto stop;
1697 	}
1698 
1699 	f2fs_flush_sit_entries(sbi, cpc);
1700 
1701 	/* save inmem log status */
1702 	f2fs_save_inmem_curseg(sbi);
1703 
1704 	err = do_checkpoint(sbi, cpc);
1705 	if (err) {
1706 		f2fs_err(sbi, "do_checkpoint failed err:%d, stop checkpoint", err);
1707 		f2fs_bug_on(sbi, !f2fs_cp_error(sbi));
1708 		f2fs_release_discard_addrs(sbi);
1709 	} else {
1710 		f2fs_clear_prefree_segments(sbi, cpc);
1711 	}
1712 
1713 	f2fs_restore_inmem_curseg(sbi);
1714 stop:
1715 	unblock_operations(sbi);
1716 	stat_inc_cp_count(sbi->stat_info);
1717 
1718 	if (cpc->reason & CP_RECOVERY)
1719 		f2fs_notice(sbi, "checkpoint: version = %llx", ckpt_ver);
1720 
1721 	/* update CP_TIME to trigger checkpoint periodically */
1722 	f2fs_update_time(sbi, CP_TIME);
1723 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint");
1724 out:
1725 	if (cpc->reason != CP_RESIZE)
1726 		f2fs_up_write(&sbi->cp_global_sem);
1727 	return err;
1728 }
1729 
1730 void f2fs_init_ino_entry_info(struct f2fs_sb_info *sbi)
1731 {
1732 	int i;
1733 
1734 	for (i = 0; i < MAX_INO_ENTRY; i++) {
1735 		struct inode_management *im = &sbi->im[i];
1736 
1737 		INIT_RADIX_TREE(&im->ino_root, GFP_ATOMIC);
1738 		spin_lock_init(&im->ino_lock);
1739 		INIT_LIST_HEAD(&im->ino_list);
1740 		im->ino_num = 0;
1741 	}
1742 
1743 	sbi->max_orphans = (sbi->blocks_per_seg - F2FS_CP_PACKS -
1744 			NR_CURSEG_PERSIST_TYPE - __cp_payload(sbi)) *
1745 				F2FS_ORPHANS_PER_BLOCK;
1746 }
1747 
1748 int __init f2fs_create_checkpoint_caches(void)
1749 {
1750 	ino_entry_slab = f2fs_kmem_cache_create("f2fs_ino_entry",
1751 			sizeof(struct ino_entry));
1752 	if (!ino_entry_slab)
1753 		return -ENOMEM;
1754 	f2fs_inode_entry_slab = f2fs_kmem_cache_create("f2fs_inode_entry",
1755 			sizeof(struct inode_entry));
1756 	if (!f2fs_inode_entry_slab) {
1757 		kmem_cache_destroy(ino_entry_slab);
1758 		return -ENOMEM;
1759 	}
1760 	return 0;
1761 }
1762 
1763 void f2fs_destroy_checkpoint_caches(void)
1764 {
1765 	kmem_cache_destroy(ino_entry_slab);
1766 	kmem_cache_destroy(f2fs_inode_entry_slab);
1767 }
1768 
1769 static int __write_checkpoint_sync(struct f2fs_sb_info *sbi)
1770 {
1771 	struct cp_control cpc = { .reason = CP_SYNC, };
1772 	int err;
1773 
1774 	f2fs_down_write(&sbi->gc_lock);
1775 	err = f2fs_write_checkpoint(sbi, &cpc);
1776 	f2fs_up_write(&sbi->gc_lock);
1777 
1778 	return err;
1779 }
1780 
1781 static void __checkpoint_and_complete_reqs(struct f2fs_sb_info *sbi)
1782 {
1783 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1784 	struct ckpt_req *req, *next;
1785 	struct llist_node *dispatch_list;
1786 	u64 sum_diff = 0, diff, count = 0;
1787 	int ret;
1788 
1789 	dispatch_list = llist_del_all(&cprc->issue_list);
1790 	if (!dispatch_list)
1791 		return;
1792 	dispatch_list = llist_reverse_order(dispatch_list);
1793 
1794 	ret = __write_checkpoint_sync(sbi);
1795 	atomic_inc(&cprc->issued_ckpt);
1796 
1797 	llist_for_each_entry_safe(req, next, dispatch_list, llnode) {
1798 		diff = (u64)ktime_ms_delta(ktime_get(), req->queue_time);
1799 		req->ret = ret;
1800 		complete(&req->wait);
1801 
1802 		sum_diff += diff;
1803 		count++;
1804 	}
1805 	atomic_sub(count, &cprc->queued_ckpt);
1806 	atomic_add(count, &cprc->total_ckpt);
1807 
1808 	spin_lock(&cprc->stat_lock);
1809 	cprc->cur_time = (unsigned int)div64_u64(sum_diff, count);
1810 	if (cprc->peak_time < cprc->cur_time)
1811 		cprc->peak_time = cprc->cur_time;
1812 	spin_unlock(&cprc->stat_lock);
1813 }
1814 
1815 static int issue_checkpoint_thread(void *data)
1816 {
1817 	struct f2fs_sb_info *sbi = data;
1818 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1819 	wait_queue_head_t *q = &cprc->ckpt_wait_queue;
1820 repeat:
1821 	if (kthread_should_stop())
1822 		return 0;
1823 
1824 	if (!llist_empty(&cprc->issue_list))
1825 		__checkpoint_and_complete_reqs(sbi);
1826 
1827 	wait_event_interruptible(*q,
1828 		kthread_should_stop() || !llist_empty(&cprc->issue_list));
1829 	goto repeat;
1830 }
1831 
1832 static void flush_remained_ckpt_reqs(struct f2fs_sb_info *sbi,
1833 		struct ckpt_req *wait_req)
1834 {
1835 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1836 
1837 	if (!llist_empty(&cprc->issue_list)) {
1838 		__checkpoint_and_complete_reqs(sbi);
1839 	} else {
1840 		/* already dispatched by issue_checkpoint_thread */
1841 		if (wait_req)
1842 			wait_for_completion(&wait_req->wait);
1843 	}
1844 }
1845 
1846 static void init_ckpt_req(struct ckpt_req *req)
1847 {
1848 	memset(req, 0, sizeof(struct ckpt_req));
1849 
1850 	init_completion(&req->wait);
1851 	req->queue_time = ktime_get();
1852 }
1853 
1854 int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi)
1855 {
1856 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1857 	struct ckpt_req req;
1858 	struct cp_control cpc;
1859 
1860 	cpc.reason = __get_cp_reason(sbi);
1861 	if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC) {
1862 		int ret;
1863 
1864 		f2fs_down_write(&sbi->gc_lock);
1865 		ret = f2fs_write_checkpoint(sbi, &cpc);
1866 		f2fs_up_write(&sbi->gc_lock);
1867 
1868 		return ret;
1869 	}
1870 
1871 	if (!cprc->f2fs_issue_ckpt)
1872 		return __write_checkpoint_sync(sbi);
1873 
1874 	init_ckpt_req(&req);
1875 
1876 	llist_add(&req.llnode, &cprc->issue_list);
1877 	atomic_inc(&cprc->queued_ckpt);
1878 
1879 	/*
1880 	 * update issue_list before we wake up issue_checkpoint thread,
1881 	 * this smp_mb() pairs with another barrier in ___wait_event(),
1882 	 * see more details in comments of waitqueue_active().
1883 	 */
1884 	smp_mb();
1885 
1886 	if (waitqueue_active(&cprc->ckpt_wait_queue))
1887 		wake_up(&cprc->ckpt_wait_queue);
1888 
1889 	if (cprc->f2fs_issue_ckpt)
1890 		wait_for_completion(&req.wait);
1891 	else
1892 		flush_remained_ckpt_reqs(sbi, &req);
1893 
1894 	return req.ret;
1895 }
1896 
1897 int f2fs_start_ckpt_thread(struct f2fs_sb_info *sbi)
1898 {
1899 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1900 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1901 
1902 	if (cprc->f2fs_issue_ckpt)
1903 		return 0;
1904 
1905 	cprc->f2fs_issue_ckpt = kthread_run(issue_checkpoint_thread, sbi,
1906 			"f2fs_ckpt-%u:%u", MAJOR(dev), MINOR(dev));
1907 	if (IS_ERR(cprc->f2fs_issue_ckpt)) {
1908 		int err = PTR_ERR(cprc->f2fs_issue_ckpt);
1909 
1910 		cprc->f2fs_issue_ckpt = NULL;
1911 		return err;
1912 	}
1913 
1914 	set_task_ioprio(cprc->f2fs_issue_ckpt, cprc->ckpt_thread_ioprio);
1915 
1916 	return 0;
1917 }
1918 
1919 void f2fs_stop_ckpt_thread(struct f2fs_sb_info *sbi)
1920 {
1921 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1922 	struct task_struct *ckpt_task;
1923 
1924 	if (!cprc->f2fs_issue_ckpt)
1925 		return;
1926 
1927 	ckpt_task = cprc->f2fs_issue_ckpt;
1928 	cprc->f2fs_issue_ckpt = NULL;
1929 	kthread_stop(ckpt_task);
1930 
1931 	f2fs_flush_ckpt_thread(sbi);
1932 }
1933 
1934 void f2fs_flush_ckpt_thread(struct f2fs_sb_info *sbi)
1935 {
1936 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1937 
1938 	flush_remained_ckpt_reqs(sbi, NULL);
1939 
1940 	/* Let's wait for the previous dispatched checkpoint. */
1941 	while (atomic_read(&cprc->queued_ckpt))
1942 		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
1943 }
1944 
1945 void f2fs_init_ckpt_req_control(struct f2fs_sb_info *sbi)
1946 {
1947 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1948 
1949 	atomic_set(&cprc->issued_ckpt, 0);
1950 	atomic_set(&cprc->total_ckpt, 0);
1951 	atomic_set(&cprc->queued_ckpt, 0);
1952 	cprc->ckpt_thread_ioprio = DEFAULT_CHECKPOINT_IOPRIO;
1953 	init_waitqueue_head(&cprc->ckpt_wait_queue);
1954 	init_llist_head(&cprc->issue_list);
1955 	spin_lock_init(&cprc->stat_lock);
1956 }
1957