xref: /openbmc/linux/fs/f2fs/checkpoint.c (revision 6726d552)
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 {
31 	f2fs_build_fault_attr(sbi, 0, 0);
32 	set_ckpt_flags(sbi, CP_ERROR_FLAG);
33 	if (!end_io)
34 		f2fs_flush_merged_writes(sbi);
35 }
36 
37 /*
38  * We guarantee no failure on the returned page.
39  */
40 struct page *f2fs_grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
41 {
42 	struct address_space *mapping = META_MAPPING(sbi);
43 	struct page *page;
44 repeat:
45 	page = f2fs_grab_cache_page(mapping, index, false);
46 	if (!page) {
47 		cond_resched();
48 		goto repeat;
49 	}
50 	f2fs_wait_on_page_writeback(page, META, true, true);
51 	if (!PageUptodate(page))
52 		SetPageUptodate(page);
53 	return page;
54 }
55 
56 static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
57 							bool is_meta)
58 {
59 	struct address_space *mapping = META_MAPPING(sbi);
60 	struct page *page;
61 	struct f2fs_io_info fio = {
62 		.sbi = sbi,
63 		.type = META,
64 		.op = REQ_OP_READ,
65 		.op_flags = REQ_META | REQ_PRIO,
66 		.old_blkaddr = index,
67 		.new_blkaddr = index,
68 		.encrypted_page = NULL,
69 		.is_por = !is_meta,
70 	};
71 	int err;
72 
73 	if (unlikely(!is_meta))
74 		fio.op_flags &= ~REQ_META;
75 repeat:
76 	page = f2fs_grab_cache_page(mapping, index, false);
77 	if (!page) {
78 		cond_resched();
79 		goto repeat;
80 	}
81 	if (PageUptodate(page))
82 		goto out;
83 
84 	fio.page = page;
85 
86 	err = f2fs_submit_page_bio(&fio);
87 	if (err) {
88 		f2fs_put_page(page, 1);
89 		return ERR_PTR(err);
90 	}
91 
92 	f2fs_update_iostat(sbi, FS_META_READ_IO, F2FS_BLKSIZE);
93 
94 	lock_page(page);
95 	if (unlikely(page->mapping != mapping)) {
96 		f2fs_put_page(page, 1);
97 		goto repeat;
98 	}
99 
100 	if (unlikely(!PageUptodate(page))) {
101 		f2fs_handle_page_eio(sbi, page->index, META);
102 		f2fs_put_page(page, 1);
103 		return ERR_PTR(-EIO);
104 	}
105 out:
106 	return page;
107 }
108 
109 struct page *f2fs_get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
110 {
111 	return __get_meta_page(sbi, index, true);
112 }
113 
114 struct page *f2fs_get_meta_page_retry(struct f2fs_sb_info *sbi, pgoff_t index)
115 {
116 	struct page *page;
117 	int count = 0;
118 
119 retry:
120 	page = __get_meta_page(sbi, index, true);
121 	if (IS_ERR(page)) {
122 		if (PTR_ERR(page) == -EIO &&
123 				++count <= DEFAULT_RETRY_IO_COUNT)
124 			goto retry;
125 		f2fs_stop_checkpoint(sbi, false);
126 	}
127 	return page;
128 }
129 
130 /* for POR only */
131 struct page *f2fs_get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index)
132 {
133 	return __get_meta_page(sbi, index, false);
134 }
135 
136 static bool __is_bitmap_valid(struct f2fs_sb_info *sbi, block_t blkaddr,
137 							int type)
138 {
139 	struct seg_entry *se;
140 	unsigned int segno, offset;
141 	bool exist;
142 
143 	if (type != DATA_GENERIC_ENHANCE && type != DATA_GENERIC_ENHANCE_READ)
144 		return true;
145 
146 	segno = GET_SEGNO(sbi, blkaddr);
147 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
148 	se = get_seg_entry(sbi, segno);
149 
150 	exist = f2fs_test_bit(offset, se->cur_valid_map);
151 	if (!exist && type == DATA_GENERIC_ENHANCE) {
152 		f2fs_err(sbi, "Inconsistent error blkaddr:%u, sit bitmap:%d",
153 			 blkaddr, exist);
154 		set_sbi_flag(sbi, SBI_NEED_FSCK);
155 		dump_stack();
156 	}
157 	return exist;
158 }
159 
160 bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
161 					block_t blkaddr, int type)
162 {
163 	switch (type) {
164 	case META_NAT:
165 		break;
166 	case META_SIT:
167 		if (unlikely(blkaddr >= SIT_BLK_CNT(sbi)))
168 			return false;
169 		break;
170 	case META_SSA:
171 		if (unlikely(blkaddr >= MAIN_BLKADDR(sbi) ||
172 			blkaddr < SM_I(sbi)->ssa_blkaddr))
173 			return false;
174 		break;
175 	case META_CP:
176 		if (unlikely(blkaddr >= SIT_I(sbi)->sit_base_addr ||
177 			blkaddr < __start_cp_addr(sbi)))
178 			return false;
179 		break;
180 	case META_POR:
181 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
182 			blkaddr < MAIN_BLKADDR(sbi)))
183 			return false;
184 		break;
185 	case DATA_GENERIC:
186 	case DATA_GENERIC_ENHANCE:
187 	case DATA_GENERIC_ENHANCE_READ:
188 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
189 				blkaddr < MAIN_BLKADDR(sbi))) {
190 			f2fs_warn(sbi, "access invalid blkaddr:%u",
191 				  blkaddr);
192 			set_sbi_flag(sbi, SBI_NEED_FSCK);
193 			dump_stack();
194 			return false;
195 		} else {
196 			return __is_bitmap_valid(sbi, blkaddr, type);
197 		}
198 		break;
199 	case META_GENERIC:
200 		if (unlikely(blkaddr < SEG0_BLKADDR(sbi) ||
201 			blkaddr >= MAIN_BLKADDR(sbi)))
202 			return false;
203 		break;
204 	default:
205 		BUG();
206 	}
207 
208 	return true;
209 }
210 
211 /*
212  * Readahead CP/NAT/SIT/SSA/POR pages
213  */
214 int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
215 							int type, bool sync)
216 {
217 	struct page *page;
218 	block_t blkno = start;
219 	struct f2fs_io_info fio = {
220 		.sbi = sbi,
221 		.type = META,
222 		.op = REQ_OP_READ,
223 		.op_flags = sync ? (REQ_META | REQ_PRIO) : REQ_RAHEAD,
224 		.encrypted_page = NULL,
225 		.in_list = false,
226 		.is_por = (type == META_POR),
227 	};
228 	struct blk_plug plug;
229 	int err;
230 
231 	if (unlikely(type == META_POR))
232 		fio.op_flags &= ~REQ_META;
233 
234 	blk_start_plug(&plug);
235 	for (; nrpages-- > 0; blkno++) {
236 
237 		if (!f2fs_is_valid_blkaddr(sbi, blkno, type))
238 			goto out;
239 
240 		switch (type) {
241 		case META_NAT:
242 			if (unlikely(blkno >=
243 					NAT_BLOCK_OFFSET(NM_I(sbi)->max_nid)))
244 				blkno = 0;
245 			/* get nat block addr */
246 			fio.new_blkaddr = current_nat_addr(sbi,
247 					blkno * NAT_ENTRY_PER_BLOCK);
248 			break;
249 		case META_SIT:
250 			if (unlikely(blkno >= TOTAL_SEGS(sbi)))
251 				goto out;
252 			/* get sit block addr */
253 			fio.new_blkaddr = current_sit_addr(sbi,
254 					blkno * SIT_ENTRY_PER_BLOCK);
255 			break;
256 		case META_SSA:
257 		case META_CP:
258 		case META_POR:
259 			fio.new_blkaddr = blkno;
260 			break;
261 		default:
262 			BUG();
263 		}
264 
265 		page = f2fs_grab_cache_page(META_MAPPING(sbi),
266 						fio.new_blkaddr, false);
267 		if (!page)
268 			continue;
269 		if (PageUptodate(page)) {
270 			f2fs_put_page(page, 1);
271 			continue;
272 		}
273 
274 		fio.page = page;
275 		err = f2fs_submit_page_bio(&fio);
276 		f2fs_put_page(page, err ? 1 : 0);
277 
278 		if (!err)
279 			f2fs_update_iostat(sbi, FS_META_READ_IO, F2FS_BLKSIZE);
280 	}
281 out:
282 	blk_finish_plug(&plug);
283 	return blkno - start;
284 }
285 
286 void f2fs_ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index,
287 							unsigned int ra_blocks)
288 {
289 	struct page *page;
290 	bool readahead = false;
291 
292 	if (ra_blocks == RECOVERY_MIN_RA_BLOCKS)
293 		return;
294 
295 	page = find_get_page(META_MAPPING(sbi), index);
296 	if (!page || !PageUptodate(page))
297 		readahead = true;
298 	f2fs_put_page(page, 0);
299 
300 	if (readahead)
301 		f2fs_ra_meta_pages(sbi, index, ra_blocks, META_POR, true);
302 }
303 
304 static int __f2fs_write_meta_page(struct page *page,
305 				struct writeback_control *wbc,
306 				enum iostat_type io_type)
307 {
308 	struct f2fs_sb_info *sbi = F2FS_P_SB(page);
309 
310 	trace_f2fs_writepage(page, META);
311 
312 	if (unlikely(f2fs_cp_error(sbi)))
313 		goto redirty_out;
314 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
315 		goto redirty_out;
316 	if (wbc->for_reclaim && page->index < GET_SUM_BLOCK(sbi, 0))
317 		goto redirty_out;
318 
319 	f2fs_do_write_meta_page(sbi, page, io_type);
320 	dec_page_count(sbi, F2FS_DIRTY_META);
321 
322 	if (wbc->for_reclaim)
323 		f2fs_submit_merged_write_cond(sbi, NULL, page, 0, META);
324 
325 	unlock_page(page);
326 
327 	if (unlikely(f2fs_cp_error(sbi)))
328 		f2fs_submit_merged_write(sbi, META);
329 
330 	return 0;
331 
332 redirty_out:
333 	redirty_page_for_writepage(wbc, page);
334 	return AOP_WRITEPAGE_ACTIVATE;
335 }
336 
337 static int f2fs_write_meta_page(struct page *page,
338 				struct writeback_control *wbc)
339 {
340 	return __f2fs_write_meta_page(page, wbc, FS_META_IO);
341 }
342 
343 static int f2fs_write_meta_pages(struct address_space *mapping,
344 				struct writeback_control *wbc)
345 {
346 	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
347 	long diff, written;
348 
349 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
350 		goto skip_write;
351 
352 	/* collect a number of dirty meta pages and write together */
353 	if (wbc->sync_mode != WB_SYNC_ALL &&
354 			get_pages(sbi, F2FS_DIRTY_META) <
355 					nr_pages_to_skip(sbi, META))
356 		goto skip_write;
357 
358 	/* if locked failed, cp will flush dirty pages instead */
359 	if (!f2fs_down_write_trylock(&sbi->cp_global_sem))
360 		goto skip_write;
361 
362 	trace_f2fs_writepages(mapping->host, wbc, META);
363 	diff = nr_pages_to_write(sbi, META, wbc);
364 	written = f2fs_sync_meta_pages(sbi, META, wbc->nr_to_write, FS_META_IO);
365 	f2fs_up_write(&sbi->cp_global_sem);
366 	wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff);
367 	return 0;
368 
369 skip_write:
370 	wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_META);
371 	trace_f2fs_writepages(mapping->host, wbc, META);
372 	return 0;
373 }
374 
375 long f2fs_sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
376 				long nr_to_write, enum iostat_type io_type)
377 {
378 	struct address_space *mapping = META_MAPPING(sbi);
379 	pgoff_t index = 0, prev = ULONG_MAX;
380 	struct pagevec pvec;
381 	long nwritten = 0;
382 	int nr_pages;
383 	struct writeback_control wbc = {
384 		.for_reclaim = 0,
385 	};
386 	struct blk_plug plug;
387 
388 	pagevec_init(&pvec);
389 
390 	blk_start_plug(&plug);
391 
392 	while ((nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
393 				PAGECACHE_TAG_DIRTY))) {
394 		int i;
395 
396 		for (i = 0; i < nr_pages; i++) {
397 			struct page *page = pvec.pages[i];
398 
399 			if (prev == ULONG_MAX)
400 				prev = page->index - 1;
401 			if (nr_to_write != LONG_MAX && page->index != prev + 1) {
402 				pagevec_release(&pvec);
403 				goto stop;
404 			}
405 
406 			lock_page(page);
407 
408 			if (unlikely(page->mapping != mapping)) {
409 continue_unlock:
410 				unlock_page(page);
411 				continue;
412 			}
413 			if (!PageDirty(page)) {
414 				/* someone wrote it for us */
415 				goto continue_unlock;
416 			}
417 
418 			f2fs_wait_on_page_writeback(page, META, true, true);
419 
420 			if (!clear_page_dirty_for_io(page))
421 				goto continue_unlock;
422 
423 			if (__f2fs_write_meta_page(page, &wbc, io_type)) {
424 				unlock_page(page);
425 				break;
426 			}
427 			nwritten++;
428 			prev = page->index;
429 			if (unlikely(nwritten >= nr_to_write))
430 				break;
431 		}
432 		pagevec_release(&pvec);
433 		cond_resched();
434 	}
435 stop:
436 	if (nwritten)
437 		f2fs_submit_merged_write(sbi, type);
438 
439 	blk_finish_plug(&plug);
440 
441 	return nwritten;
442 }
443 
444 static bool f2fs_dirty_meta_folio(struct address_space *mapping,
445 		struct folio *folio)
446 {
447 	trace_f2fs_set_page_dirty(&folio->page, META);
448 
449 	if (!folio_test_uptodate(folio))
450 		folio_mark_uptodate(folio);
451 	if (!folio_test_dirty(folio)) {
452 		filemap_dirty_folio(mapping, folio);
453 		inc_page_count(F2FS_M_SB(mapping), F2FS_DIRTY_META);
454 		set_page_private_reference(&folio->page);
455 		return true;
456 	}
457 	return false;
458 }
459 
460 const struct address_space_operations f2fs_meta_aops = {
461 	.writepage	= f2fs_write_meta_page,
462 	.writepages	= f2fs_write_meta_pages,
463 	.dirty_folio	= f2fs_dirty_meta_folio,
464 	.invalidate_folio = f2fs_invalidate_folio,
465 	.release_folio	= f2fs_release_folio,
466 	.migrate_folio	= filemap_migrate_folio,
467 };
468 
469 static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino,
470 						unsigned int devidx, int type)
471 {
472 	struct inode_management *im = &sbi->im[type];
473 	struct ino_entry *e = NULL, *new = NULL;
474 
475 	if (type == FLUSH_INO) {
476 		rcu_read_lock();
477 		e = radix_tree_lookup(&im->ino_root, ino);
478 		rcu_read_unlock();
479 	}
480 
481 retry:
482 	if (!e)
483 		new = f2fs_kmem_cache_alloc(ino_entry_slab,
484 						GFP_NOFS, true, NULL);
485 
486 	radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
487 
488 	spin_lock(&im->ino_lock);
489 	e = radix_tree_lookup(&im->ino_root, ino);
490 	if (!e) {
491 		if (!new) {
492 			spin_unlock(&im->ino_lock);
493 			goto retry;
494 		}
495 		e = new;
496 		if (unlikely(radix_tree_insert(&im->ino_root, ino, e)))
497 			f2fs_bug_on(sbi, 1);
498 
499 		memset(e, 0, sizeof(struct ino_entry));
500 		e->ino = ino;
501 
502 		list_add_tail(&e->list, &im->ino_list);
503 		if (type != ORPHAN_INO)
504 			im->ino_num++;
505 	}
506 
507 	if (type == FLUSH_INO)
508 		f2fs_set_bit(devidx, (char *)&e->dirty_device);
509 
510 	spin_unlock(&im->ino_lock);
511 	radix_tree_preload_end();
512 
513 	if (new && e != new)
514 		kmem_cache_free(ino_entry_slab, new);
515 }
516 
517 static void __remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
518 {
519 	struct inode_management *im = &sbi->im[type];
520 	struct ino_entry *e;
521 
522 	spin_lock(&im->ino_lock);
523 	e = radix_tree_lookup(&im->ino_root, ino);
524 	if (e) {
525 		list_del(&e->list);
526 		radix_tree_delete(&im->ino_root, ino);
527 		im->ino_num--;
528 		spin_unlock(&im->ino_lock);
529 		kmem_cache_free(ino_entry_slab, e);
530 		return;
531 	}
532 	spin_unlock(&im->ino_lock);
533 }
534 
535 void f2fs_add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
536 {
537 	/* add new dirty ino entry into list */
538 	__add_ino_entry(sbi, ino, 0, type);
539 }
540 
541 void f2fs_remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
542 {
543 	/* remove dirty ino entry from list */
544 	__remove_ino_entry(sbi, ino, type);
545 }
546 
547 /* mode should be APPEND_INO, UPDATE_INO or TRANS_DIR_INO */
548 bool f2fs_exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode)
549 {
550 	struct inode_management *im = &sbi->im[mode];
551 	struct ino_entry *e;
552 
553 	spin_lock(&im->ino_lock);
554 	e = radix_tree_lookup(&im->ino_root, ino);
555 	spin_unlock(&im->ino_lock);
556 	return e ? true : false;
557 }
558 
559 void f2fs_release_ino_entry(struct f2fs_sb_info *sbi, bool all)
560 {
561 	struct ino_entry *e, *tmp;
562 	int i;
563 
564 	for (i = all ? ORPHAN_INO : APPEND_INO; i < MAX_INO_ENTRY; i++) {
565 		struct inode_management *im = &sbi->im[i];
566 
567 		spin_lock(&im->ino_lock);
568 		list_for_each_entry_safe(e, tmp, &im->ino_list, list) {
569 			list_del(&e->list);
570 			radix_tree_delete(&im->ino_root, e->ino);
571 			kmem_cache_free(ino_entry_slab, e);
572 			im->ino_num--;
573 		}
574 		spin_unlock(&im->ino_lock);
575 	}
576 }
577 
578 void f2fs_set_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
579 					unsigned int devidx, int type)
580 {
581 	__add_ino_entry(sbi, ino, devidx, type);
582 }
583 
584 bool f2fs_is_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
585 					unsigned int devidx, int type)
586 {
587 	struct inode_management *im = &sbi->im[type];
588 	struct ino_entry *e;
589 	bool is_dirty = false;
590 
591 	spin_lock(&im->ino_lock);
592 	e = radix_tree_lookup(&im->ino_root, ino);
593 	if (e && f2fs_test_bit(devidx, (char *)&e->dirty_device))
594 		is_dirty = true;
595 	spin_unlock(&im->ino_lock);
596 	return is_dirty;
597 }
598 
599 int f2fs_acquire_orphan_inode(struct f2fs_sb_info *sbi)
600 {
601 	struct inode_management *im = &sbi->im[ORPHAN_INO];
602 	int err = 0;
603 
604 	spin_lock(&im->ino_lock);
605 
606 	if (time_to_inject(sbi, FAULT_ORPHAN)) {
607 		spin_unlock(&im->ino_lock);
608 		f2fs_show_injection_info(sbi, FAULT_ORPHAN);
609 		return -ENOSPC;
610 	}
611 
612 	if (unlikely(im->ino_num >= sbi->max_orphans))
613 		err = -ENOSPC;
614 	else
615 		im->ino_num++;
616 	spin_unlock(&im->ino_lock);
617 
618 	return err;
619 }
620 
621 void f2fs_release_orphan_inode(struct f2fs_sb_info *sbi)
622 {
623 	struct inode_management *im = &sbi->im[ORPHAN_INO];
624 
625 	spin_lock(&im->ino_lock);
626 	f2fs_bug_on(sbi, im->ino_num == 0);
627 	im->ino_num--;
628 	spin_unlock(&im->ino_lock);
629 }
630 
631 void f2fs_add_orphan_inode(struct inode *inode)
632 {
633 	/* add new orphan ino entry into list */
634 	__add_ino_entry(F2FS_I_SB(inode), inode->i_ino, 0, ORPHAN_INO);
635 	f2fs_update_inode_page(inode);
636 }
637 
638 void f2fs_remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
639 {
640 	/* remove orphan entry from orphan list */
641 	__remove_ino_entry(sbi, ino, ORPHAN_INO);
642 }
643 
644 static int recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
645 {
646 	struct inode *inode;
647 	struct node_info ni;
648 	int err;
649 
650 	inode = f2fs_iget_retry(sbi->sb, ino);
651 	if (IS_ERR(inode)) {
652 		/*
653 		 * there should be a bug that we can't find the entry
654 		 * to orphan inode.
655 		 */
656 		f2fs_bug_on(sbi, PTR_ERR(inode) == -ENOENT);
657 		return PTR_ERR(inode);
658 	}
659 
660 	err = f2fs_dquot_initialize(inode);
661 	if (err) {
662 		iput(inode);
663 		goto err_out;
664 	}
665 
666 	clear_nlink(inode);
667 
668 	/* truncate all the data during iput */
669 	iput(inode);
670 
671 	err = f2fs_get_node_info(sbi, ino, &ni, false);
672 	if (err)
673 		goto err_out;
674 
675 	/* ENOMEM was fully retried in f2fs_evict_inode. */
676 	if (ni.blk_addr != NULL_ADDR) {
677 		err = -EIO;
678 		goto err_out;
679 	}
680 	return 0;
681 
682 err_out:
683 	set_sbi_flag(sbi, SBI_NEED_FSCK);
684 	f2fs_warn(sbi, "%s: orphan failed (ino=%x), run fsck to fix.",
685 		  __func__, ino);
686 	return err;
687 }
688 
689 int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi)
690 {
691 	block_t start_blk, orphan_blocks, i, j;
692 	unsigned int s_flags = sbi->sb->s_flags;
693 	int err = 0;
694 #ifdef CONFIG_QUOTA
695 	int quota_enabled;
696 #endif
697 
698 	if (!is_set_ckpt_flags(sbi, CP_ORPHAN_PRESENT_FLAG))
699 		return 0;
700 
701 	if (bdev_read_only(sbi->sb->s_bdev)) {
702 		f2fs_info(sbi, "write access unavailable, skipping orphan cleanup");
703 		return 0;
704 	}
705 
706 	if (s_flags & SB_RDONLY) {
707 		f2fs_info(sbi, "orphan cleanup on readonly fs");
708 		sbi->sb->s_flags &= ~SB_RDONLY;
709 	}
710 
711 #ifdef CONFIG_QUOTA
712 	/*
713 	 * Turn on quotas which were not enabled for read-only mounts if
714 	 * filesystem has quota feature, so that they are updated correctly.
715 	 */
716 	quota_enabled = f2fs_enable_quota_files(sbi, s_flags & SB_RDONLY);
717 #endif
718 
719 	start_blk = __start_cp_addr(sbi) + 1 + __cp_payload(sbi);
720 	orphan_blocks = __start_sum_addr(sbi) - 1 - __cp_payload(sbi);
721 
722 	f2fs_ra_meta_pages(sbi, start_blk, orphan_blocks, META_CP, true);
723 
724 	for (i = 0; i < orphan_blocks; i++) {
725 		struct page *page;
726 		struct f2fs_orphan_block *orphan_blk;
727 
728 		page = f2fs_get_meta_page(sbi, start_blk + i);
729 		if (IS_ERR(page)) {
730 			err = PTR_ERR(page);
731 			goto out;
732 		}
733 
734 		orphan_blk = (struct f2fs_orphan_block *)page_address(page);
735 		for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
736 			nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
737 
738 			err = recover_orphan_inode(sbi, ino);
739 			if (err) {
740 				f2fs_put_page(page, 1);
741 				goto out;
742 			}
743 		}
744 		f2fs_put_page(page, 1);
745 	}
746 	/* clear Orphan Flag */
747 	clear_ckpt_flags(sbi, CP_ORPHAN_PRESENT_FLAG);
748 out:
749 	set_sbi_flag(sbi, SBI_IS_RECOVERED);
750 
751 #ifdef CONFIG_QUOTA
752 	/* Turn quotas off */
753 	if (quota_enabled)
754 		f2fs_quota_off_umount(sbi->sb);
755 #endif
756 	sbi->sb->s_flags = s_flags; /* Restore SB_RDONLY status */
757 
758 	return err;
759 }
760 
761 static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
762 {
763 	struct list_head *head;
764 	struct f2fs_orphan_block *orphan_blk = NULL;
765 	unsigned int nentries = 0;
766 	unsigned short index = 1;
767 	unsigned short orphan_blocks;
768 	struct page *page = NULL;
769 	struct ino_entry *orphan = NULL;
770 	struct inode_management *im = &sbi->im[ORPHAN_INO];
771 
772 	orphan_blocks = GET_ORPHAN_BLOCKS(im->ino_num);
773 
774 	/*
775 	 * we don't need to do spin_lock(&im->ino_lock) here, since all the
776 	 * orphan inode operations are covered under f2fs_lock_op().
777 	 * And, spin_lock should be avoided due to page operations below.
778 	 */
779 	head = &im->ino_list;
780 
781 	/* loop for each orphan inode entry and write them in Jornal block */
782 	list_for_each_entry(orphan, head, list) {
783 		if (!page) {
784 			page = f2fs_grab_meta_page(sbi, start_blk++);
785 			orphan_blk =
786 				(struct f2fs_orphan_block *)page_address(page);
787 			memset(orphan_blk, 0, sizeof(*orphan_blk));
788 		}
789 
790 		orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
791 
792 		if (nentries == F2FS_ORPHANS_PER_BLOCK) {
793 			/*
794 			 * an orphan block is full of 1020 entries,
795 			 * then we need to flush current orphan blocks
796 			 * and bring another one in memory
797 			 */
798 			orphan_blk->blk_addr = cpu_to_le16(index);
799 			orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
800 			orphan_blk->entry_count = cpu_to_le32(nentries);
801 			set_page_dirty(page);
802 			f2fs_put_page(page, 1);
803 			index++;
804 			nentries = 0;
805 			page = NULL;
806 		}
807 	}
808 
809 	if (page) {
810 		orphan_blk->blk_addr = cpu_to_le16(index);
811 		orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
812 		orphan_blk->entry_count = cpu_to_le32(nentries);
813 		set_page_dirty(page);
814 		f2fs_put_page(page, 1);
815 	}
816 }
817 
818 static __u32 f2fs_checkpoint_chksum(struct f2fs_sb_info *sbi,
819 						struct f2fs_checkpoint *ckpt)
820 {
821 	unsigned int chksum_ofs = le32_to_cpu(ckpt->checksum_offset);
822 	__u32 chksum;
823 
824 	chksum = f2fs_crc32(sbi, ckpt, chksum_ofs);
825 	if (chksum_ofs < CP_CHKSUM_OFFSET) {
826 		chksum_ofs += sizeof(chksum);
827 		chksum = f2fs_chksum(sbi, chksum, (__u8 *)ckpt + chksum_ofs,
828 						F2FS_BLKSIZE - chksum_ofs);
829 	}
830 	return chksum;
831 }
832 
833 static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
834 		struct f2fs_checkpoint **cp_block, struct page **cp_page,
835 		unsigned long long *version)
836 {
837 	size_t crc_offset = 0;
838 	__u32 crc;
839 
840 	*cp_page = f2fs_get_meta_page(sbi, cp_addr);
841 	if (IS_ERR(*cp_page))
842 		return PTR_ERR(*cp_page);
843 
844 	*cp_block = (struct f2fs_checkpoint *)page_address(*cp_page);
845 
846 	crc_offset = le32_to_cpu((*cp_block)->checksum_offset);
847 	if (crc_offset < CP_MIN_CHKSUM_OFFSET ||
848 			crc_offset > CP_CHKSUM_OFFSET) {
849 		f2fs_put_page(*cp_page, 1);
850 		f2fs_warn(sbi, "invalid crc_offset: %zu", crc_offset);
851 		return -EINVAL;
852 	}
853 
854 	crc = f2fs_checkpoint_chksum(sbi, *cp_block);
855 	if (crc != cur_cp_crc(*cp_block)) {
856 		f2fs_put_page(*cp_page, 1);
857 		f2fs_warn(sbi, "invalid crc value");
858 		return -EINVAL;
859 	}
860 
861 	*version = cur_cp_version(*cp_block);
862 	return 0;
863 }
864 
865 static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
866 				block_t cp_addr, unsigned long long *version)
867 {
868 	struct page *cp_page_1 = NULL, *cp_page_2 = NULL;
869 	struct f2fs_checkpoint *cp_block = NULL;
870 	unsigned long long cur_version = 0, pre_version = 0;
871 	unsigned int cp_blocks;
872 	int err;
873 
874 	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
875 					&cp_page_1, version);
876 	if (err)
877 		return NULL;
878 
879 	cp_blocks = le32_to_cpu(cp_block->cp_pack_total_block_count);
880 
881 	if (cp_blocks > sbi->blocks_per_seg || cp_blocks <= F2FS_CP_PACKS) {
882 		f2fs_warn(sbi, "invalid cp_pack_total_block_count:%u",
883 			  le32_to_cpu(cp_block->cp_pack_total_block_count));
884 		goto invalid_cp;
885 	}
886 	pre_version = *version;
887 
888 	cp_addr += cp_blocks - 1;
889 	err = get_checkpoint_version(sbi, cp_addr, &cp_block,
890 					&cp_page_2, version);
891 	if (err)
892 		goto invalid_cp;
893 	cur_version = *version;
894 
895 	if (cur_version == pre_version) {
896 		*version = cur_version;
897 		f2fs_put_page(cp_page_2, 1);
898 		return cp_page_1;
899 	}
900 	f2fs_put_page(cp_page_2, 1);
901 invalid_cp:
902 	f2fs_put_page(cp_page_1, 1);
903 	return NULL;
904 }
905 
906 int f2fs_get_valid_checkpoint(struct f2fs_sb_info *sbi)
907 {
908 	struct f2fs_checkpoint *cp_block;
909 	struct f2fs_super_block *fsb = sbi->raw_super;
910 	struct page *cp1, *cp2, *cur_page;
911 	unsigned long blk_size = sbi->blocksize;
912 	unsigned long long cp1_version = 0, cp2_version = 0;
913 	unsigned long long cp_start_blk_no;
914 	unsigned int cp_blks = 1 + __cp_payload(sbi);
915 	block_t cp_blk_no;
916 	int i;
917 	int err;
918 
919 	sbi->ckpt = f2fs_kvzalloc(sbi, array_size(blk_size, cp_blks),
920 				  GFP_KERNEL);
921 	if (!sbi->ckpt)
922 		return -ENOMEM;
923 	/*
924 	 * Finding out valid cp block involves read both
925 	 * sets( cp pack 1 and cp pack 2)
926 	 */
927 	cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
928 	cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
929 
930 	/* The second checkpoint pack should start at the next segment */
931 	cp_start_blk_no += ((unsigned long long)1) <<
932 				le32_to_cpu(fsb->log_blocks_per_seg);
933 	cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
934 
935 	if (cp1 && cp2) {
936 		if (ver_after(cp2_version, cp1_version))
937 			cur_page = cp2;
938 		else
939 			cur_page = cp1;
940 	} else if (cp1) {
941 		cur_page = cp1;
942 	} else if (cp2) {
943 		cur_page = cp2;
944 	} else {
945 		err = -EFSCORRUPTED;
946 		goto fail_no_cp;
947 	}
948 
949 	cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
950 	memcpy(sbi->ckpt, cp_block, blk_size);
951 
952 	if (cur_page == cp1)
953 		sbi->cur_cp_pack = 1;
954 	else
955 		sbi->cur_cp_pack = 2;
956 
957 	/* Sanity checking of checkpoint */
958 	if (f2fs_sanity_check_ckpt(sbi)) {
959 		err = -EFSCORRUPTED;
960 		goto free_fail_no_cp;
961 	}
962 
963 	if (cp_blks <= 1)
964 		goto done;
965 
966 	cp_blk_no = le32_to_cpu(fsb->cp_blkaddr);
967 	if (cur_page == cp2)
968 		cp_blk_no += 1 << le32_to_cpu(fsb->log_blocks_per_seg);
969 
970 	for (i = 1; i < cp_blks; i++) {
971 		void *sit_bitmap_ptr;
972 		unsigned char *ckpt = (unsigned char *)sbi->ckpt;
973 
974 		cur_page = f2fs_get_meta_page(sbi, cp_blk_no + i);
975 		if (IS_ERR(cur_page)) {
976 			err = PTR_ERR(cur_page);
977 			goto free_fail_no_cp;
978 		}
979 		sit_bitmap_ptr = page_address(cur_page);
980 		memcpy(ckpt + i * blk_size, sit_bitmap_ptr, blk_size);
981 		f2fs_put_page(cur_page, 1);
982 	}
983 done:
984 	f2fs_put_page(cp1, 1);
985 	f2fs_put_page(cp2, 1);
986 	return 0;
987 
988 free_fail_no_cp:
989 	f2fs_put_page(cp1, 1);
990 	f2fs_put_page(cp2, 1);
991 fail_no_cp:
992 	kvfree(sbi->ckpt);
993 	return err;
994 }
995 
996 static void __add_dirty_inode(struct inode *inode, enum inode_type type)
997 {
998 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
999 	int flag = (type == DIR_INODE) ? FI_DIRTY_DIR : FI_DIRTY_FILE;
1000 
1001 	if (is_inode_flag_set(inode, flag))
1002 		return;
1003 
1004 	set_inode_flag(inode, flag);
1005 	list_add_tail(&F2FS_I(inode)->dirty_list, &sbi->inode_list[type]);
1006 	stat_inc_dirty_inode(sbi, type);
1007 }
1008 
1009 static void __remove_dirty_inode(struct inode *inode, enum inode_type type)
1010 {
1011 	int flag = (type == DIR_INODE) ? FI_DIRTY_DIR : FI_DIRTY_FILE;
1012 
1013 	if (get_dirty_pages(inode) || !is_inode_flag_set(inode, flag))
1014 		return;
1015 
1016 	list_del_init(&F2FS_I(inode)->dirty_list);
1017 	clear_inode_flag(inode, flag);
1018 	stat_dec_dirty_inode(F2FS_I_SB(inode), type);
1019 }
1020 
1021 void f2fs_update_dirty_folio(struct inode *inode, struct folio *folio)
1022 {
1023 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1024 	enum inode_type type = S_ISDIR(inode->i_mode) ? DIR_INODE : FILE_INODE;
1025 
1026 	if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
1027 			!S_ISLNK(inode->i_mode))
1028 		return;
1029 
1030 	spin_lock(&sbi->inode_lock[type]);
1031 	if (type != FILE_INODE || test_opt(sbi, DATA_FLUSH))
1032 		__add_dirty_inode(inode, type);
1033 	inode_inc_dirty_pages(inode);
1034 	spin_unlock(&sbi->inode_lock[type]);
1035 
1036 	set_page_private_reference(&folio->page);
1037 }
1038 
1039 void f2fs_remove_dirty_inode(struct inode *inode)
1040 {
1041 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1042 	enum inode_type type = S_ISDIR(inode->i_mode) ? DIR_INODE : FILE_INODE;
1043 
1044 	if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
1045 			!S_ISLNK(inode->i_mode))
1046 		return;
1047 
1048 	if (type == FILE_INODE && !test_opt(sbi, DATA_FLUSH))
1049 		return;
1050 
1051 	spin_lock(&sbi->inode_lock[type]);
1052 	__remove_dirty_inode(inode, type);
1053 	spin_unlock(&sbi->inode_lock[type]);
1054 }
1055 
1056 int f2fs_sync_dirty_inodes(struct f2fs_sb_info *sbi, enum inode_type type)
1057 {
1058 	struct list_head *head;
1059 	struct inode *inode;
1060 	struct f2fs_inode_info *fi;
1061 	bool is_dir = (type == DIR_INODE);
1062 	unsigned long ino = 0;
1063 
1064 	trace_f2fs_sync_dirty_inodes_enter(sbi->sb, is_dir,
1065 				get_pages(sbi, is_dir ?
1066 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1067 retry:
1068 	if (unlikely(f2fs_cp_error(sbi))) {
1069 		trace_f2fs_sync_dirty_inodes_exit(sbi->sb, is_dir,
1070 				get_pages(sbi, is_dir ?
1071 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1072 		return -EIO;
1073 	}
1074 
1075 	spin_lock(&sbi->inode_lock[type]);
1076 
1077 	head = &sbi->inode_list[type];
1078 	if (list_empty(head)) {
1079 		spin_unlock(&sbi->inode_lock[type]);
1080 		trace_f2fs_sync_dirty_inodes_exit(sbi->sb, is_dir,
1081 				get_pages(sbi, is_dir ?
1082 				F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA));
1083 		return 0;
1084 	}
1085 	fi = list_first_entry(head, struct f2fs_inode_info, dirty_list);
1086 	inode = igrab(&fi->vfs_inode);
1087 	spin_unlock(&sbi->inode_lock[type]);
1088 	if (inode) {
1089 		unsigned long cur_ino = inode->i_ino;
1090 
1091 		F2FS_I(inode)->cp_task = current;
1092 
1093 		filemap_fdatawrite(inode->i_mapping);
1094 
1095 		F2FS_I(inode)->cp_task = NULL;
1096 
1097 		iput(inode);
1098 		/* We need to give cpu to another writers. */
1099 		if (ino == cur_ino)
1100 			cond_resched();
1101 		else
1102 			ino = cur_ino;
1103 	} else {
1104 		/*
1105 		 * We should submit bio, since it exists several
1106 		 * wribacking dentry pages in the freeing inode.
1107 		 */
1108 		f2fs_submit_merged_write(sbi, DATA);
1109 		cond_resched();
1110 	}
1111 	goto retry;
1112 }
1113 
1114 int f2fs_sync_inode_meta(struct f2fs_sb_info *sbi)
1115 {
1116 	struct list_head *head = &sbi->inode_list[DIRTY_META];
1117 	struct inode *inode;
1118 	struct f2fs_inode_info *fi;
1119 	s64 total = get_pages(sbi, F2FS_DIRTY_IMETA);
1120 
1121 	while (total--) {
1122 		if (unlikely(f2fs_cp_error(sbi)))
1123 			return -EIO;
1124 
1125 		spin_lock(&sbi->inode_lock[DIRTY_META]);
1126 		if (list_empty(head)) {
1127 			spin_unlock(&sbi->inode_lock[DIRTY_META]);
1128 			return 0;
1129 		}
1130 		fi = list_first_entry(head, struct f2fs_inode_info,
1131 							gdirty_list);
1132 		inode = igrab(&fi->vfs_inode);
1133 		spin_unlock(&sbi->inode_lock[DIRTY_META]);
1134 		if (inode) {
1135 			sync_inode_metadata(inode, 0);
1136 
1137 			/* it's on eviction */
1138 			if (is_inode_flag_set(inode, FI_DIRTY_INODE))
1139 				f2fs_update_inode_page(inode);
1140 			iput(inode);
1141 		}
1142 	}
1143 	return 0;
1144 }
1145 
1146 static void __prepare_cp_block(struct f2fs_sb_info *sbi)
1147 {
1148 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1149 	struct f2fs_nm_info *nm_i = NM_I(sbi);
1150 	nid_t last_nid = nm_i->next_scan_nid;
1151 
1152 	next_free_nid(sbi, &last_nid);
1153 	ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
1154 	ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
1155 	ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
1156 	ckpt->next_free_nid = cpu_to_le32(last_nid);
1157 }
1158 
1159 static bool __need_flush_quota(struct f2fs_sb_info *sbi)
1160 {
1161 	bool ret = false;
1162 
1163 	if (!is_journalled_quota(sbi))
1164 		return false;
1165 
1166 	if (!f2fs_down_write_trylock(&sbi->quota_sem))
1167 		return true;
1168 	if (is_sbi_flag_set(sbi, SBI_QUOTA_SKIP_FLUSH)) {
1169 		ret = false;
1170 	} else if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_REPAIR)) {
1171 		ret = false;
1172 	} else if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_FLUSH)) {
1173 		clear_sbi_flag(sbi, SBI_QUOTA_NEED_FLUSH);
1174 		ret = true;
1175 	} else if (get_pages(sbi, F2FS_DIRTY_QDATA)) {
1176 		ret = true;
1177 	}
1178 	f2fs_up_write(&sbi->quota_sem);
1179 	return ret;
1180 }
1181 
1182 /*
1183  * Freeze all the FS-operations for checkpoint.
1184  */
1185 static int block_operations(struct f2fs_sb_info *sbi)
1186 {
1187 	struct writeback_control wbc = {
1188 		.sync_mode = WB_SYNC_ALL,
1189 		.nr_to_write = LONG_MAX,
1190 		.for_reclaim = 0,
1191 	};
1192 	int err = 0, cnt = 0;
1193 
1194 	/*
1195 	 * Let's flush inline_data in dirty node pages.
1196 	 */
1197 	f2fs_flush_inline_data(sbi);
1198 
1199 retry_flush_quotas:
1200 	f2fs_lock_all(sbi);
1201 	if (__need_flush_quota(sbi)) {
1202 		int locked;
1203 
1204 		if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) {
1205 			set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH);
1206 			set_sbi_flag(sbi, SBI_QUOTA_NEED_FLUSH);
1207 			goto retry_flush_dents;
1208 		}
1209 		f2fs_unlock_all(sbi);
1210 
1211 		/* only failed during mount/umount/freeze/quotactl */
1212 		locked = down_read_trylock(&sbi->sb->s_umount);
1213 		f2fs_quota_sync(sbi->sb, -1);
1214 		if (locked)
1215 			up_read(&sbi->sb->s_umount);
1216 		cond_resched();
1217 		goto retry_flush_quotas;
1218 	}
1219 
1220 retry_flush_dents:
1221 	/* write all the dirty dentry pages */
1222 	if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
1223 		f2fs_unlock_all(sbi);
1224 		err = f2fs_sync_dirty_inodes(sbi, DIR_INODE);
1225 		if (err)
1226 			return err;
1227 		cond_resched();
1228 		goto retry_flush_quotas;
1229 	}
1230 
1231 	/*
1232 	 * POR: we should ensure that there are no dirty node pages
1233 	 * until finishing nat/sit flush. inode->i_blocks can be updated.
1234 	 */
1235 	f2fs_down_write(&sbi->node_change);
1236 
1237 	if (get_pages(sbi, F2FS_DIRTY_IMETA)) {
1238 		f2fs_up_write(&sbi->node_change);
1239 		f2fs_unlock_all(sbi);
1240 		err = f2fs_sync_inode_meta(sbi);
1241 		if (err)
1242 			return err;
1243 		cond_resched();
1244 		goto retry_flush_quotas;
1245 	}
1246 
1247 retry_flush_nodes:
1248 	f2fs_down_write(&sbi->node_write);
1249 
1250 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
1251 		f2fs_up_write(&sbi->node_write);
1252 		atomic_inc(&sbi->wb_sync_req[NODE]);
1253 		err = f2fs_sync_node_pages(sbi, &wbc, false, FS_CP_NODE_IO);
1254 		atomic_dec(&sbi->wb_sync_req[NODE]);
1255 		if (err) {
1256 			f2fs_up_write(&sbi->node_change);
1257 			f2fs_unlock_all(sbi);
1258 			return err;
1259 		}
1260 		cond_resched();
1261 		goto retry_flush_nodes;
1262 	}
1263 
1264 	/*
1265 	 * sbi->node_change is used only for AIO write_begin path which produces
1266 	 * dirty node blocks and some checkpoint values by block allocation.
1267 	 */
1268 	__prepare_cp_block(sbi);
1269 	f2fs_up_write(&sbi->node_change);
1270 	return err;
1271 }
1272 
1273 static void unblock_operations(struct f2fs_sb_info *sbi)
1274 {
1275 	f2fs_up_write(&sbi->node_write);
1276 	f2fs_unlock_all(sbi);
1277 }
1278 
1279 void f2fs_wait_on_all_pages(struct f2fs_sb_info *sbi, int type)
1280 {
1281 	DEFINE_WAIT(wait);
1282 
1283 	for (;;) {
1284 		if (!get_pages(sbi, type))
1285 			break;
1286 
1287 		if (unlikely(f2fs_cp_error(sbi)))
1288 			break;
1289 
1290 		if (type == F2FS_DIRTY_META)
1291 			f2fs_sync_meta_pages(sbi, META, LONG_MAX,
1292 							FS_CP_META_IO);
1293 		else if (type == F2FS_WB_CP_DATA)
1294 			f2fs_submit_merged_write(sbi, DATA);
1295 
1296 		prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
1297 		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
1298 	}
1299 	finish_wait(&sbi->cp_wait, &wait);
1300 }
1301 
1302 static void update_ckpt_flags(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1303 {
1304 	unsigned long orphan_num = sbi->im[ORPHAN_INO].ino_num;
1305 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1306 	unsigned long flags;
1307 
1308 	if (cpc->reason & CP_UMOUNT) {
1309 		if (le32_to_cpu(ckpt->cp_pack_total_block_count) +
1310 			NM_I(sbi)->nat_bits_blocks > sbi->blocks_per_seg) {
1311 			clear_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
1312 			f2fs_notice(sbi, "Disable nat_bits due to no space");
1313 		} else if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG) &&
1314 						f2fs_nat_bitmap_enabled(sbi)) {
1315 			f2fs_enable_nat_bits(sbi);
1316 			set_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
1317 			f2fs_notice(sbi, "Rebuild and enable nat_bits");
1318 		}
1319 	}
1320 
1321 	spin_lock_irqsave(&sbi->cp_lock, flags);
1322 
1323 	if (cpc->reason & CP_TRIMMED)
1324 		__set_ckpt_flags(ckpt, CP_TRIMMED_FLAG);
1325 	else
1326 		__clear_ckpt_flags(ckpt, CP_TRIMMED_FLAG);
1327 
1328 	if (cpc->reason & CP_UMOUNT)
1329 		__set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
1330 	else
1331 		__clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
1332 
1333 	if (cpc->reason & CP_FASTBOOT)
1334 		__set_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
1335 	else
1336 		__clear_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
1337 
1338 	if (orphan_num)
1339 		__set_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
1340 	else
1341 		__clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
1342 
1343 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
1344 		__set_ckpt_flags(ckpt, CP_FSCK_FLAG);
1345 
1346 	if (is_sbi_flag_set(sbi, SBI_IS_RESIZEFS))
1347 		__set_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
1348 	else
1349 		__clear_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
1350 
1351 	if (is_sbi_flag_set(sbi, SBI_CP_DISABLED))
1352 		__set_ckpt_flags(ckpt, CP_DISABLED_FLAG);
1353 	else
1354 		__clear_ckpt_flags(ckpt, CP_DISABLED_FLAG);
1355 
1356 	if (is_sbi_flag_set(sbi, SBI_CP_DISABLED_QUICK))
1357 		__set_ckpt_flags(ckpt, CP_DISABLED_QUICK_FLAG);
1358 	else
1359 		__clear_ckpt_flags(ckpt, CP_DISABLED_QUICK_FLAG);
1360 
1361 	if (is_sbi_flag_set(sbi, SBI_QUOTA_SKIP_FLUSH))
1362 		__set_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1363 	else
1364 		__clear_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1365 
1366 	if (is_sbi_flag_set(sbi, SBI_QUOTA_NEED_REPAIR))
1367 		__set_ckpt_flags(ckpt, CP_QUOTA_NEED_FSCK_FLAG);
1368 
1369 	/* set this flag to activate crc|cp_ver for recovery */
1370 	__set_ckpt_flags(ckpt, CP_CRC_RECOVERY_FLAG);
1371 	__clear_ckpt_flags(ckpt, CP_NOCRC_RECOVERY_FLAG);
1372 
1373 	spin_unlock_irqrestore(&sbi->cp_lock, flags);
1374 }
1375 
1376 static void commit_checkpoint(struct f2fs_sb_info *sbi,
1377 	void *src, block_t blk_addr)
1378 {
1379 	struct writeback_control wbc = {
1380 		.for_reclaim = 0,
1381 	};
1382 
1383 	/*
1384 	 * pagevec_lookup_tag and lock_page again will take
1385 	 * some extra time. Therefore, f2fs_update_meta_pages and
1386 	 * f2fs_sync_meta_pages are combined in this function.
1387 	 */
1388 	struct page *page = f2fs_grab_meta_page(sbi, blk_addr);
1389 	int err;
1390 
1391 	f2fs_wait_on_page_writeback(page, META, true, true);
1392 
1393 	memcpy(page_address(page), src, PAGE_SIZE);
1394 
1395 	set_page_dirty(page);
1396 	if (unlikely(!clear_page_dirty_for_io(page)))
1397 		f2fs_bug_on(sbi, 1);
1398 
1399 	/* writeout cp pack 2 page */
1400 	err = __f2fs_write_meta_page(page, &wbc, FS_CP_META_IO);
1401 	if (unlikely(err && f2fs_cp_error(sbi))) {
1402 		f2fs_put_page(page, 1);
1403 		return;
1404 	}
1405 
1406 	f2fs_bug_on(sbi, err);
1407 	f2fs_put_page(page, 0);
1408 
1409 	/* submit checkpoint (with barrier if NOBARRIER is not set) */
1410 	f2fs_submit_merged_write(sbi, META_FLUSH);
1411 }
1412 
1413 static inline u64 get_sectors_written(struct block_device *bdev)
1414 {
1415 	return (u64)part_stat_read(bdev, sectors[STAT_WRITE]);
1416 }
1417 
1418 u64 f2fs_get_sectors_written(struct f2fs_sb_info *sbi)
1419 {
1420 	if (f2fs_is_multi_device(sbi)) {
1421 		u64 sectors = 0;
1422 		int i;
1423 
1424 		for (i = 0; i < sbi->s_ndevs; i++)
1425 			sectors += get_sectors_written(FDEV(i).bdev);
1426 
1427 		return sectors;
1428 	}
1429 
1430 	return get_sectors_written(sbi->sb->s_bdev);
1431 }
1432 
1433 static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1434 {
1435 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1436 	struct f2fs_nm_info *nm_i = NM_I(sbi);
1437 	unsigned long orphan_num = sbi->im[ORPHAN_INO].ino_num, flags;
1438 	block_t start_blk;
1439 	unsigned int data_sum_blocks, orphan_blocks;
1440 	__u32 crc32 = 0;
1441 	int i;
1442 	int cp_payload_blks = __cp_payload(sbi);
1443 	struct curseg_info *seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
1444 	u64 kbytes_written;
1445 	int err;
1446 
1447 	/* Flush all the NAT/SIT pages */
1448 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
1449 
1450 	/* start to update checkpoint, cp ver is already updated previously */
1451 	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi, true));
1452 	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
1453 	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
1454 		ckpt->cur_node_segno[i] =
1455 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
1456 		ckpt->cur_node_blkoff[i] =
1457 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
1458 		ckpt->alloc_type[i + CURSEG_HOT_NODE] =
1459 				curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
1460 	}
1461 	for (i = 0; i < NR_CURSEG_DATA_TYPE; i++) {
1462 		ckpt->cur_data_segno[i] =
1463 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
1464 		ckpt->cur_data_blkoff[i] =
1465 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
1466 		ckpt->alloc_type[i + CURSEG_HOT_DATA] =
1467 				curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
1468 	}
1469 
1470 	/* 2 cp + n data seg summary + orphan inode blocks */
1471 	data_sum_blocks = f2fs_npages_for_summary_flush(sbi, false);
1472 	spin_lock_irqsave(&sbi->cp_lock, flags);
1473 	if (data_sum_blocks < NR_CURSEG_DATA_TYPE)
1474 		__set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
1475 	else
1476 		__clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
1477 	spin_unlock_irqrestore(&sbi->cp_lock, flags);
1478 
1479 	orphan_blocks = GET_ORPHAN_BLOCKS(orphan_num);
1480 	ckpt->cp_pack_start_sum = cpu_to_le32(1 + cp_payload_blks +
1481 			orphan_blocks);
1482 
1483 	if (__remain_node_summaries(cpc->reason))
1484 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS +
1485 				cp_payload_blks + data_sum_blocks +
1486 				orphan_blocks + NR_CURSEG_NODE_TYPE);
1487 	else
1488 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS +
1489 				cp_payload_blks + data_sum_blocks +
1490 				orphan_blocks);
1491 
1492 	/* update ckpt flag for checkpoint */
1493 	update_ckpt_flags(sbi, cpc);
1494 
1495 	/* update SIT/NAT bitmap */
1496 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
1497 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
1498 
1499 	crc32 = f2fs_checkpoint_chksum(sbi, ckpt);
1500 	*((__le32 *)((unsigned char *)ckpt +
1501 				le32_to_cpu(ckpt->checksum_offset)))
1502 				= cpu_to_le32(crc32);
1503 
1504 	start_blk = __start_cp_next_addr(sbi);
1505 
1506 	/* write nat bits */
1507 	if ((cpc->reason & CP_UMOUNT) &&
1508 			is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG)) {
1509 		__u64 cp_ver = cur_cp_version(ckpt);
1510 		block_t blk;
1511 
1512 		cp_ver |= ((__u64)crc32 << 32);
1513 		*(__le64 *)nm_i->nat_bits = cpu_to_le64(cp_ver);
1514 
1515 		blk = start_blk + sbi->blocks_per_seg - nm_i->nat_bits_blocks;
1516 		for (i = 0; i < nm_i->nat_bits_blocks; i++)
1517 			f2fs_update_meta_page(sbi, nm_i->nat_bits +
1518 					(i << F2FS_BLKSIZE_BITS), blk + i);
1519 	}
1520 
1521 	/* write out checkpoint buffer at block 0 */
1522 	f2fs_update_meta_page(sbi, ckpt, start_blk++);
1523 
1524 	for (i = 1; i < 1 + cp_payload_blks; i++)
1525 		f2fs_update_meta_page(sbi, (char *)ckpt + i * F2FS_BLKSIZE,
1526 							start_blk++);
1527 
1528 	if (orphan_num) {
1529 		write_orphan_inodes(sbi, start_blk);
1530 		start_blk += orphan_blocks;
1531 	}
1532 
1533 	f2fs_write_data_summaries(sbi, start_blk);
1534 	start_blk += data_sum_blocks;
1535 
1536 	/* Record write statistics in the hot node summary */
1537 	kbytes_written = sbi->kbytes_written;
1538 	kbytes_written += (f2fs_get_sectors_written(sbi) -
1539 				sbi->sectors_written_start) >> 1;
1540 	seg_i->journal->info.kbytes_written = cpu_to_le64(kbytes_written);
1541 
1542 	if (__remain_node_summaries(cpc->reason)) {
1543 		f2fs_write_node_summaries(sbi, start_blk);
1544 		start_blk += NR_CURSEG_NODE_TYPE;
1545 	}
1546 
1547 	/* update user_block_counts */
1548 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1549 	percpu_counter_set(&sbi->alloc_valid_block_count, 0);
1550 	percpu_counter_set(&sbi->rf_node_block_count, 0);
1551 
1552 	/* Here, we have one bio having CP pack except cp pack 2 page */
1553 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
1554 	/* Wait for all dirty meta pages to be submitted for IO */
1555 	f2fs_wait_on_all_pages(sbi, F2FS_DIRTY_META);
1556 
1557 	/* wait for previous submitted meta pages writeback */
1558 	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
1559 
1560 	/* flush all device cache */
1561 	err = f2fs_flush_device_cache(sbi);
1562 	if (err)
1563 		return err;
1564 
1565 	/* barrier and flush checkpoint cp pack 2 page if it can */
1566 	commit_checkpoint(sbi, ckpt, start_blk);
1567 	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
1568 
1569 	/*
1570 	 * invalidate intermediate page cache borrowed from meta inode which are
1571 	 * used for migration of encrypted, verity or compressed inode's blocks.
1572 	 */
1573 	if (f2fs_sb_has_encrypt(sbi) || f2fs_sb_has_verity(sbi) ||
1574 		f2fs_sb_has_compression(sbi))
1575 		invalidate_mapping_pages(META_MAPPING(sbi),
1576 				MAIN_BLKADDR(sbi), MAX_BLKADDR(sbi) - 1);
1577 
1578 	f2fs_release_ino_entry(sbi, false);
1579 
1580 	f2fs_reset_fsync_node_info(sbi);
1581 
1582 	clear_sbi_flag(sbi, SBI_IS_DIRTY);
1583 	clear_sbi_flag(sbi, SBI_NEED_CP);
1584 	clear_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH);
1585 
1586 	spin_lock(&sbi->stat_lock);
1587 	sbi->unusable_block_count = 0;
1588 	spin_unlock(&sbi->stat_lock);
1589 
1590 	__set_cp_next_pack(sbi);
1591 
1592 	/*
1593 	 * redirty superblock if metadata like node page or inode cache is
1594 	 * updated during writing checkpoint.
1595 	 */
1596 	if (get_pages(sbi, F2FS_DIRTY_NODES) ||
1597 			get_pages(sbi, F2FS_DIRTY_IMETA))
1598 		set_sbi_flag(sbi, SBI_IS_DIRTY);
1599 
1600 	f2fs_bug_on(sbi, get_pages(sbi, F2FS_DIRTY_DENTS));
1601 
1602 	return unlikely(f2fs_cp_error(sbi)) ? -EIO : 0;
1603 }
1604 
1605 int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1606 {
1607 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1608 	unsigned long long ckpt_ver;
1609 	int err = 0;
1610 
1611 	if (f2fs_readonly(sbi->sb) || f2fs_hw_is_readonly(sbi))
1612 		return -EROFS;
1613 
1614 	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) {
1615 		if (cpc->reason != CP_PAUSE)
1616 			return 0;
1617 		f2fs_warn(sbi, "Start checkpoint disabled!");
1618 	}
1619 	if (cpc->reason != CP_RESIZE)
1620 		f2fs_down_write(&sbi->cp_global_sem);
1621 
1622 	if (!is_sbi_flag_set(sbi, SBI_IS_DIRTY) &&
1623 		((cpc->reason & CP_FASTBOOT) || (cpc->reason & CP_SYNC) ||
1624 		((cpc->reason & CP_DISCARD) && !sbi->discard_blks)))
1625 		goto out;
1626 	if (unlikely(f2fs_cp_error(sbi))) {
1627 		err = -EIO;
1628 		goto out;
1629 	}
1630 
1631 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "start block_ops");
1632 
1633 	err = block_operations(sbi);
1634 	if (err)
1635 		goto out;
1636 
1637 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish block_ops");
1638 
1639 	f2fs_flush_merged_writes(sbi);
1640 
1641 	/* this is the case of multiple fstrims without any changes */
1642 	if (cpc->reason & CP_DISCARD) {
1643 		if (!f2fs_exist_trim_candidates(sbi, cpc)) {
1644 			unblock_operations(sbi);
1645 			goto out;
1646 		}
1647 
1648 		if (NM_I(sbi)->nat_cnt[DIRTY_NAT] == 0 &&
1649 				SIT_I(sbi)->dirty_sentries == 0 &&
1650 				prefree_segments(sbi) == 0) {
1651 			f2fs_flush_sit_entries(sbi, cpc);
1652 			f2fs_clear_prefree_segments(sbi, cpc);
1653 			unblock_operations(sbi);
1654 			goto out;
1655 		}
1656 	}
1657 
1658 	/*
1659 	 * update checkpoint pack index
1660 	 * Increase the version number so that
1661 	 * SIT entries and seg summaries are written at correct place
1662 	 */
1663 	ckpt_ver = cur_cp_version(ckpt);
1664 	ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
1665 
1666 	/* write cached NAT/SIT entries to NAT/SIT area */
1667 	err = f2fs_flush_nat_entries(sbi, cpc);
1668 	if (err) {
1669 		f2fs_err(sbi, "f2fs_flush_nat_entries failed err:%d, stop checkpoint", err);
1670 		f2fs_bug_on(sbi, !f2fs_cp_error(sbi));
1671 		goto stop;
1672 	}
1673 
1674 	f2fs_flush_sit_entries(sbi, cpc);
1675 
1676 	/* save inmem log status */
1677 	f2fs_save_inmem_curseg(sbi);
1678 
1679 	err = do_checkpoint(sbi, cpc);
1680 	if (err) {
1681 		f2fs_err(sbi, "do_checkpoint failed err:%d, stop checkpoint", err);
1682 		f2fs_bug_on(sbi, !f2fs_cp_error(sbi));
1683 		f2fs_release_discard_addrs(sbi);
1684 	} else {
1685 		f2fs_clear_prefree_segments(sbi, cpc);
1686 	}
1687 
1688 	f2fs_restore_inmem_curseg(sbi);
1689 stop:
1690 	unblock_operations(sbi);
1691 	stat_inc_cp_count(sbi->stat_info);
1692 
1693 	if (cpc->reason & CP_RECOVERY)
1694 		f2fs_notice(sbi, "checkpoint: version = %llx", ckpt_ver);
1695 
1696 	/* update CP_TIME to trigger checkpoint periodically */
1697 	f2fs_update_time(sbi, CP_TIME);
1698 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint");
1699 out:
1700 	if (cpc->reason != CP_RESIZE)
1701 		f2fs_up_write(&sbi->cp_global_sem);
1702 	return err;
1703 }
1704 
1705 void f2fs_init_ino_entry_info(struct f2fs_sb_info *sbi)
1706 {
1707 	int i;
1708 
1709 	for (i = 0; i < MAX_INO_ENTRY; i++) {
1710 		struct inode_management *im = &sbi->im[i];
1711 
1712 		INIT_RADIX_TREE(&im->ino_root, GFP_ATOMIC);
1713 		spin_lock_init(&im->ino_lock);
1714 		INIT_LIST_HEAD(&im->ino_list);
1715 		im->ino_num = 0;
1716 	}
1717 
1718 	sbi->max_orphans = (sbi->blocks_per_seg - F2FS_CP_PACKS -
1719 			NR_CURSEG_PERSIST_TYPE - __cp_payload(sbi)) *
1720 				F2FS_ORPHANS_PER_BLOCK;
1721 }
1722 
1723 int __init f2fs_create_checkpoint_caches(void)
1724 {
1725 	ino_entry_slab = f2fs_kmem_cache_create("f2fs_ino_entry",
1726 			sizeof(struct ino_entry));
1727 	if (!ino_entry_slab)
1728 		return -ENOMEM;
1729 	f2fs_inode_entry_slab = f2fs_kmem_cache_create("f2fs_inode_entry",
1730 			sizeof(struct inode_entry));
1731 	if (!f2fs_inode_entry_slab) {
1732 		kmem_cache_destroy(ino_entry_slab);
1733 		return -ENOMEM;
1734 	}
1735 	return 0;
1736 }
1737 
1738 void f2fs_destroy_checkpoint_caches(void)
1739 {
1740 	kmem_cache_destroy(ino_entry_slab);
1741 	kmem_cache_destroy(f2fs_inode_entry_slab);
1742 }
1743 
1744 static int __write_checkpoint_sync(struct f2fs_sb_info *sbi)
1745 {
1746 	struct cp_control cpc = { .reason = CP_SYNC, };
1747 	int err;
1748 
1749 	f2fs_down_write(&sbi->gc_lock);
1750 	err = f2fs_write_checkpoint(sbi, &cpc);
1751 	f2fs_up_write(&sbi->gc_lock);
1752 
1753 	return err;
1754 }
1755 
1756 static void __checkpoint_and_complete_reqs(struct f2fs_sb_info *sbi)
1757 {
1758 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1759 	struct ckpt_req *req, *next;
1760 	struct llist_node *dispatch_list;
1761 	u64 sum_diff = 0, diff, count = 0;
1762 	int ret;
1763 
1764 	dispatch_list = llist_del_all(&cprc->issue_list);
1765 	if (!dispatch_list)
1766 		return;
1767 	dispatch_list = llist_reverse_order(dispatch_list);
1768 
1769 	ret = __write_checkpoint_sync(sbi);
1770 	atomic_inc(&cprc->issued_ckpt);
1771 
1772 	llist_for_each_entry_safe(req, next, dispatch_list, llnode) {
1773 		diff = (u64)ktime_ms_delta(ktime_get(), req->queue_time);
1774 		req->ret = ret;
1775 		complete(&req->wait);
1776 
1777 		sum_diff += diff;
1778 		count++;
1779 	}
1780 	atomic_sub(count, &cprc->queued_ckpt);
1781 	atomic_add(count, &cprc->total_ckpt);
1782 
1783 	spin_lock(&cprc->stat_lock);
1784 	cprc->cur_time = (unsigned int)div64_u64(sum_diff, count);
1785 	if (cprc->peak_time < cprc->cur_time)
1786 		cprc->peak_time = cprc->cur_time;
1787 	spin_unlock(&cprc->stat_lock);
1788 }
1789 
1790 static int issue_checkpoint_thread(void *data)
1791 {
1792 	struct f2fs_sb_info *sbi = data;
1793 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1794 	wait_queue_head_t *q = &cprc->ckpt_wait_queue;
1795 repeat:
1796 	if (kthread_should_stop())
1797 		return 0;
1798 
1799 	if (!llist_empty(&cprc->issue_list))
1800 		__checkpoint_and_complete_reqs(sbi);
1801 
1802 	wait_event_interruptible(*q,
1803 		kthread_should_stop() || !llist_empty(&cprc->issue_list));
1804 	goto repeat;
1805 }
1806 
1807 static void flush_remained_ckpt_reqs(struct f2fs_sb_info *sbi,
1808 		struct ckpt_req *wait_req)
1809 {
1810 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1811 
1812 	if (!llist_empty(&cprc->issue_list)) {
1813 		__checkpoint_and_complete_reqs(sbi);
1814 	} else {
1815 		/* already dispatched by issue_checkpoint_thread */
1816 		if (wait_req)
1817 			wait_for_completion(&wait_req->wait);
1818 	}
1819 }
1820 
1821 static void init_ckpt_req(struct ckpt_req *req)
1822 {
1823 	memset(req, 0, sizeof(struct ckpt_req));
1824 
1825 	init_completion(&req->wait);
1826 	req->queue_time = ktime_get();
1827 }
1828 
1829 int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi)
1830 {
1831 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1832 	struct ckpt_req req;
1833 	struct cp_control cpc;
1834 
1835 	cpc.reason = __get_cp_reason(sbi);
1836 	if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC) {
1837 		int ret;
1838 
1839 		f2fs_down_write(&sbi->gc_lock);
1840 		ret = f2fs_write_checkpoint(sbi, &cpc);
1841 		f2fs_up_write(&sbi->gc_lock);
1842 
1843 		return ret;
1844 	}
1845 
1846 	if (!cprc->f2fs_issue_ckpt)
1847 		return __write_checkpoint_sync(sbi);
1848 
1849 	init_ckpt_req(&req);
1850 
1851 	llist_add(&req.llnode, &cprc->issue_list);
1852 	atomic_inc(&cprc->queued_ckpt);
1853 
1854 	/*
1855 	 * update issue_list before we wake up issue_checkpoint thread,
1856 	 * this smp_mb() pairs with another barrier in ___wait_event(),
1857 	 * see more details in comments of waitqueue_active().
1858 	 */
1859 	smp_mb();
1860 
1861 	if (waitqueue_active(&cprc->ckpt_wait_queue))
1862 		wake_up(&cprc->ckpt_wait_queue);
1863 
1864 	if (cprc->f2fs_issue_ckpt)
1865 		wait_for_completion(&req.wait);
1866 	else
1867 		flush_remained_ckpt_reqs(sbi, &req);
1868 
1869 	return req.ret;
1870 }
1871 
1872 int f2fs_start_ckpt_thread(struct f2fs_sb_info *sbi)
1873 {
1874 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1875 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1876 
1877 	if (cprc->f2fs_issue_ckpt)
1878 		return 0;
1879 
1880 	cprc->f2fs_issue_ckpt = kthread_run(issue_checkpoint_thread, sbi,
1881 			"f2fs_ckpt-%u:%u", MAJOR(dev), MINOR(dev));
1882 	if (IS_ERR(cprc->f2fs_issue_ckpt)) {
1883 		cprc->f2fs_issue_ckpt = NULL;
1884 		return -ENOMEM;
1885 	}
1886 
1887 	set_task_ioprio(cprc->f2fs_issue_ckpt, cprc->ckpt_thread_ioprio);
1888 
1889 	return 0;
1890 }
1891 
1892 void f2fs_stop_ckpt_thread(struct f2fs_sb_info *sbi)
1893 {
1894 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1895 
1896 	if (cprc->f2fs_issue_ckpt) {
1897 		struct task_struct *ckpt_task = cprc->f2fs_issue_ckpt;
1898 
1899 		cprc->f2fs_issue_ckpt = NULL;
1900 		kthread_stop(ckpt_task);
1901 
1902 		flush_remained_ckpt_reqs(sbi, NULL);
1903 	}
1904 }
1905 
1906 void f2fs_init_ckpt_req_control(struct f2fs_sb_info *sbi)
1907 {
1908 	struct ckpt_req_control *cprc = &sbi->cprc_info;
1909 
1910 	atomic_set(&cprc->issued_ckpt, 0);
1911 	atomic_set(&cprc->total_ckpt, 0);
1912 	atomic_set(&cprc->queued_ckpt, 0);
1913 	cprc->ckpt_thread_ioprio = DEFAULT_CHECKPOINT_IOPRIO;
1914 	init_waitqueue_head(&cprc->ckpt_wait_queue);
1915 	init_llist_head(&cprc->issue_list);
1916 	spin_lock_init(&cprc->stat_lock);
1917 }
1918