xref: /openbmc/linux/fs/f2fs/checkpoint.c (revision 55d1cdb25a815ba92a917ae579c27cc3ffb9a57d)
1 /*
2  * fs/f2fs/checkpoint.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/fs.h>
12 #include <linux/bio.h>
13 #include <linux/mpage.h>
14 #include <linux/writeback.h>
15 #include <linux/blkdev.h>
16 #include <linux/f2fs_fs.h>
17 #include <linux/pagevec.h>
18 #include <linux/swap.h>
19 
20 #include "f2fs.h"
21 #include "node.h"
22 #include "segment.h"
23 #include "trace.h"
24 #include <trace/events/f2fs.h>
25 
26 static struct kmem_cache *ino_entry_slab;
27 struct kmem_cache *inode_entry_slab;
28 
29 /*
30  * We guarantee no failure on the returned page.
31  */
32 struct page *grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
33 {
34 	struct address_space *mapping = META_MAPPING(sbi);
35 	struct page *page = NULL;
36 repeat:
37 	page = grab_cache_page(mapping, index);
38 	if (!page) {
39 		cond_resched();
40 		goto repeat;
41 	}
42 	f2fs_wait_on_page_writeback(page, META);
43 	SetPageUptodate(page);
44 	return page;
45 }
46 
47 /*
48  * We guarantee no failure on the returned page.
49  */
50 static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
51 							bool is_meta)
52 {
53 	struct address_space *mapping = META_MAPPING(sbi);
54 	struct page *page;
55 	struct f2fs_io_info fio = {
56 		.sbi = sbi,
57 		.type = META,
58 		.rw = READ_SYNC | REQ_META | REQ_PRIO,
59 		.blk_addr = index,
60 		.encrypted_page = NULL,
61 	};
62 
63 	if (unlikely(!is_meta))
64 		fio.rw &= ~REQ_META;
65 repeat:
66 	page = grab_cache_page(mapping, index);
67 	if (!page) {
68 		cond_resched();
69 		goto repeat;
70 	}
71 	if (PageUptodate(page))
72 		goto out;
73 
74 	fio.page = page;
75 
76 	if (f2fs_submit_page_bio(&fio)) {
77 		f2fs_put_page(page, 1);
78 		goto repeat;
79 	}
80 
81 	lock_page(page);
82 	if (unlikely(page->mapping != mapping)) {
83 		f2fs_put_page(page, 1);
84 		goto repeat;
85 	}
86 
87 	/*
88 	 * if there is any IO error when accessing device, make our filesystem
89 	 * readonly and make sure do not write checkpoint with non-uptodate
90 	 * meta page.
91 	 */
92 	if (unlikely(!PageUptodate(page)))
93 		f2fs_stop_checkpoint(sbi);
94 out:
95 	return page;
96 }
97 
98 struct page *get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
99 {
100 	return __get_meta_page(sbi, index, true);
101 }
102 
103 /* for POR only */
104 struct page *get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index)
105 {
106 	return __get_meta_page(sbi, index, false);
107 }
108 
109 bool is_valid_blkaddr(struct f2fs_sb_info *sbi, block_t blkaddr, int type)
110 {
111 	switch (type) {
112 	case META_NAT:
113 		break;
114 	case META_SIT:
115 		if (unlikely(blkaddr >= SIT_BLK_CNT(sbi)))
116 			return false;
117 		break;
118 	case META_SSA:
119 		if (unlikely(blkaddr >= MAIN_BLKADDR(sbi) ||
120 			blkaddr < SM_I(sbi)->ssa_blkaddr))
121 			return false;
122 		break;
123 	case META_CP:
124 		if (unlikely(blkaddr >= SIT_I(sbi)->sit_base_addr ||
125 			blkaddr < __start_cp_addr(sbi)))
126 			return false;
127 		break;
128 	case META_POR:
129 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
130 			blkaddr < MAIN_BLKADDR(sbi)))
131 			return false;
132 		break;
133 	default:
134 		BUG();
135 	}
136 
137 	return true;
138 }
139 
140 /*
141  * Readahead CP/NAT/SIT/SSA pages
142  */
143 int ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
144 							int type, bool sync)
145 {
146 	block_t prev_blk_addr = 0;
147 	struct page *page;
148 	block_t blkno = start;
149 	struct f2fs_io_info fio = {
150 		.sbi = sbi,
151 		.type = META,
152 		.rw = sync ? (READ_SYNC | REQ_META | REQ_PRIO) : READA,
153 		.encrypted_page = NULL,
154 	};
155 
156 	if (unlikely(type == META_POR))
157 		fio.rw &= ~REQ_META;
158 
159 	for (; nrpages-- > 0; blkno++) {
160 
161 		if (!is_valid_blkaddr(sbi, blkno, type))
162 			goto out;
163 
164 		switch (type) {
165 		case META_NAT:
166 			if (unlikely(blkno >=
167 					NAT_BLOCK_OFFSET(NM_I(sbi)->max_nid)))
168 				blkno = 0;
169 			/* get nat block addr */
170 			fio.blk_addr = current_nat_addr(sbi,
171 					blkno * NAT_ENTRY_PER_BLOCK);
172 			break;
173 		case META_SIT:
174 			/* get sit block addr */
175 			fio.blk_addr = current_sit_addr(sbi,
176 					blkno * SIT_ENTRY_PER_BLOCK);
177 			if (blkno != start && prev_blk_addr + 1 != fio.blk_addr)
178 				goto out;
179 			prev_blk_addr = fio.blk_addr;
180 			break;
181 		case META_SSA:
182 		case META_CP:
183 		case META_POR:
184 			fio.blk_addr = blkno;
185 			break;
186 		default:
187 			BUG();
188 		}
189 
190 		page = grab_cache_page(META_MAPPING(sbi), fio.blk_addr);
191 		if (!page)
192 			continue;
193 		if (PageUptodate(page)) {
194 			f2fs_put_page(page, 1);
195 			continue;
196 		}
197 
198 		fio.page = page;
199 		f2fs_submit_page_mbio(&fio);
200 		f2fs_put_page(page, 0);
201 	}
202 out:
203 	f2fs_submit_merged_bio(sbi, META, READ);
204 	return blkno - start;
205 }
206 
207 void ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index)
208 {
209 	struct page *page;
210 	bool readahead = false;
211 
212 	page = find_get_page(META_MAPPING(sbi), index);
213 	if (!page || (page && !PageUptodate(page)))
214 		readahead = true;
215 	f2fs_put_page(page, 0);
216 
217 	if (readahead)
218 		ra_meta_pages(sbi, index, MAX_BIO_BLOCKS(sbi), META_POR, true);
219 }
220 
221 static int f2fs_write_meta_page(struct page *page,
222 				struct writeback_control *wbc)
223 {
224 	struct f2fs_sb_info *sbi = F2FS_P_SB(page);
225 
226 	trace_f2fs_writepage(page, META);
227 
228 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
229 		goto redirty_out;
230 	if (wbc->for_reclaim && page->index < GET_SUM_BLOCK(sbi, 0))
231 		goto redirty_out;
232 	if (unlikely(f2fs_cp_error(sbi)))
233 		goto redirty_out;
234 
235 	f2fs_wait_on_page_writeback(page, META);
236 	write_meta_page(sbi, page);
237 	dec_page_count(sbi, F2FS_DIRTY_META);
238 	unlock_page(page);
239 
240 	if (wbc->for_reclaim)
241 		f2fs_submit_merged_bio(sbi, META, WRITE);
242 	return 0;
243 
244 redirty_out:
245 	redirty_page_for_writepage(wbc, page);
246 	return AOP_WRITEPAGE_ACTIVATE;
247 }
248 
249 static int f2fs_write_meta_pages(struct address_space *mapping,
250 				struct writeback_control *wbc)
251 {
252 	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
253 	long diff, written;
254 
255 	trace_f2fs_writepages(mapping->host, wbc, META);
256 
257 	/* collect a number of dirty meta pages and write together */
258 	if (wbc->for_kupdate ||
259 		get_pages(sbi, F2FS_DIRTY_META) < nr_pages_to_skip(sbi, META))
260 		goto skip_write;
261 
262 	/* if mounting is failed, skip writing node pages */
263 	mutex_lock(&sbi->cp_mutex);
264 	diff = nr_pages_to_write(sbi, META, wbc);
265 	written = sync_meta_pages(sbi, META, wbc->nr_to_write);
266 	mutex_unlock(&sbi->cp_mutex);
267 	wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff);
268 	return 0;
269 
270 skip_write:
271 	wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_META);
272 	return 0;
273 }
274 
275 long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
276 						long nr_to_write)
277 {
278 	struct address_space *mapping = META_MAPPING(sbi);
279 	pgoff_t index = 0, end = LONG_MAX, prev = LONG_MAX;
280 	struct pagevec pvec;
281 	long nwritten = 0;
282 	struct writeback_control wbc = {
283 		.for_reclaim = 0,
284 	};
285 
286 	pagevec_init(&pvec, 0);
287 
288 	while (index <= end) {
289 		int i, nr_pages;
290 		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
291 				PAGECACHE_TAG_DIRTY,
292 				min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
293 		if (unlikely(nr_pages == 0))
294 			break;
295 
296 		for (i = 0; i < nr_pages; i++) {
297 			struct page *page = pvec.pages[i];
298 
299 			if (prev == LONG_MAX)
300 				prev = page->index - 1;
301 			if (nr_to_write != LONG_MAX && page->index != prev + 1) {
302 				pagevec_release(&pvec);
303 				goto stop;
304 			}
305 
306 			lock_page(page);
307 
308 			if (unlikely(page->mapping != mapping)) {
309 continue_unlock:
310 				unlock_page(page);
311 				continue;
312 			}
313 			if (!PageDirty(page)) {
314 				/* someone wrote it for us */
315 				goto continue_unlock;
316 			}
317 
318 			if (!clear_page_dirty_for_io(page))
319 				goto continue_unlock;
320 
321 			if (mapping->a_ops->writepage(page, &wbc)) {
322 				unlock_page(page);
323 				break;
324 			}
325 			nwritten++;
326 			prev = page->index;
327 			if (unlikely(nwritten >= nr_to_write))
328 				break;
329 		}
330 		pagevec_release(&pvec);
331 		cond_resched();
332 	}
333 stop:
334 	if (nwritten)
335 		f2fs_submit_merged_bio(sbi, type, WRITE);
336 
337 	return nwritten;
338 }
339 
340 static int f2fs_set_meta_page_dirty(struct page *page)
341 {
342 	trace_f2fs_set_page_dirty(page, META);
343 
344 	SetPageUptodate(page);
345 	if (!PageDirty(page)) {
346 		__set_page_dirty_nobuffers(page);
347 		inc_page_count(F2FS_P_SB(page), F2FS_DIRTY_META);
348 		SetPagePrivate(page);
349 		f2fs_trace_pid(page);
350 		return 1;
351 	}
352 	return 0;
353 }
354 
355 const struct address_space_operations f2fs_meta_aops = {
356 	.writepage	= f2fs_write_meta_page,
357 	.writepages	= f2fs_write_meta_pages,
358 	.set_page_dirty	= f2fs_set_meta_page_dirty,
359 	.invalidatepage = f2fs_invalidate_page,
360 	.releasepage	= f2fs_release_page,
361 };
362 
363 static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
364 {
365 	struct inode_management *im = &sbi->im[type];
366 	struct ino_entry *e, *tmp;
367 
368 	tmp = f2fs_kmem_cache_alloc(ino_entry_slab, GFP_NOFS);
369 retry:
370 	radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
371 
372 	spin_lock(&im->ino_lock);
373 	e = radix_tree_lookup(&im->ino_root, ino);
374 	if (!e) {
375 		e = tmp;
376 		if (radix_tree_insert(&im->ino_root, ino, e)) {
377 			spin_unlock(&im->ino_lock);
378 			radix_tree_preload_end();
379 			goto retry;
380 		}
381 		memset(e, 0, sizeof(struct ino_entry));
382 		e->ino = ino;
383 
384 		list_add_tail(&e->list, &im->ino_list);
385 		if (type != ORPHAN_INO)
386 			im->ino_num++;
387 	}
388 	spin_unlock(&im->ino_lock);
389 	radix_tree_preload_end();
390 
391 	if (e != tmp)
392 		kmem_cache_free(ino_entry_slab, tmp);
393 }
394 
395 static void __remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
396 {
397 	struct inode_management *im = &sbi->im[type];
398 	struct ino_entry *e;
399 
400 	spin_lock(&im->ino_lock);
401 	e = radix_tree_lookup(&im->ino_root, ino);
402 	if (e) {
403 		list_del(&e->list);
404 		radix_tree_delete(&im->ino_root, ino);
405 		im->ino_num--;
406 		spin_unlock(&im->ino_lock);
407 		kmem_cache_free(ino_entry_slab, e);
408 		return;
409 	}
410 	spin_unlock(&im->ino_lock);
411 }
412 
413 void add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
414 {
415 	/* add new dirty ino entry into list */
416 	__add_ino_entry(sbi, ino, type);
417 }
418 
419 void remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type)
420 {
421 	/* remove dirty ino entry from list */
422 	__remove_ino_entry(sbi, ino, type);
423 }
424 
425 /* mode should be APPEND_INO or UPDATE_INO */
426 bool exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode)
427 {
428 	struct inode_management *im = &sbi->im[mode];
429 	struct ino_entry *e;
430 
431 	spin_lock(&im->ino_lock);
432 	e = radix_tree_lookup(&im->ino_root, ino);
433 	spin_unlock(&im->ino_lock);
434 	return e ? true : false;
435 }
436 
437 void release_ino_entry(struct f2fs_sb_info *sbi)
438 {
439 	struct ino_entry *e, *tmp;
440 	int i;
441 
442 	for (i = APPEND_INO; i <= UPDATE_INO; i++) {
443 		struct inode_management *im = &sbi->im[i];
444 
445 		spin_lock(&im->ino_lock);
446 		list_for_each_entry_safe(e, tmp, &im->ino_list, list) {
447 			list_del(&e->list);
448 			radix_tree_delete(&im->ino_root, e->ino);
449 			kmem_cache_free(ino_entry_slab, e);
450 			im->ino_num--;
451 		}
452 		spin_unlock(&im->ino_lock);
453 	}
454 }
455 
456 int acquire_orphan_inode(struct f2fs_sb_info *sbi)
457 {
458 	struct inode_management *im = &sbi->im[ORPHAN_INO];
459 	int err = 0;
460 
461 	spin_lock(&im->ino_lock);
462 	if (unlikely(im->ino_num >= sbi->max_orphans))
463 		err = -ENOSPC;
464 	else
465 		im->ino_num++;
466 	spin_unlock(&im->ino_lock);
467 
468 	return err;
469 }
470 
471 void release_orphan_inode(struct f2fs_sb_info *sbi)
472 {
473 	struct inode_management *im = &sbi->im[ORPHAN_INO];
474 
475 	spin_lock(&im->ino_lock);
476 	f2fs_bug_on(sbi, im->ino_num == 0);
477 	im->ino_num--;
478 	spin_unlock(&im->ino_lock);
479 }
480 
481 void add_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
482 {
483 	/* add new orphan ino entry into list */
484 	__add_ino_entry(sbi, ino, ORPHAN_INO);
485 }
486 
487 void remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
488 {
489 	/* remove orphan entry from orphan list */
490 	__remove_ino_entry(sbi, ino, ORPHAN_INO);
491 }
492 
493 static int recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
494 {
495 	struct inode *inode;
496 
497 	inode = f2fs_iget(sbi->sb, ino);
498 	if (IS_ERR(inode)) {
499 		/*
500 		 * there should be a bug that we can't find the entry
501 		 * to orphan inode.
502 		 */
503 		f2fs_bug_on(sbi, PTR_ERR(inode) == -ENOENT);
504 		return PTR_ERR(inode);
505 	}
506 
507 	clear_nlink(inode);
508 
509 	/* truncate all the data during iput */
510 	iput(inode);
511 	return 0;
512 }
513 
514 int recover_orphan_inodes(struct f2fs_sb_info *sbi)
515 {
516 	block_t start_blk, orphan_blocks, i, j;
517 	int err;
518 
519 	if (!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG))
520 		return 0;
521 
522 	start_blk = __start_cp_addr(sbi) + 1 + __cp_payload(sbi);
523 	orphan_blocks = __start_sum_addr(sbi) - 1 - __cp_payload(sbi);
524 
525 	ra_meta_pages(sbi, start_blk, orphan_blocks, META_CP, true);
526 
527 	for (i = 0; i < orphan_blocks; i++) {
528 		struct page *page = get_meta_page(sbi, start_blk + i);
529 		struct f2fs_orphan_block *orphan_blk;
530 
531 		orphan_blk = (struct f2fs_orphan_block *)page_address(page);
532 		for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
533 			nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
534 			err = recover_orphan_inode(sbi, ino);
535 			if (err) {
536 				f2fs_put_page(page, 1);
537 				return err;
538 			}
539 		}
540 		f2fs_put_page(page, 1);
541 	}
542 	/* clear Orphan Flag */
543 	clear_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG);
544 	return 0;
545 }
546 
547 static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
548 {
549 	struct list_head *head;
550 	struct f2fs_orphan_block *orphan_blk = NULL;
551 	unsigned int nentries = 0;
552 	unsigned short index = 1;
553 	unsigned short orphan_blocks;
554 	struct page *page = NULL;
555 	struct ino_entry *orphan = NULL;
556 	struct inode_management *im = &sbi->im[ORPHAN_INO];
557 
558 	orphan_blocks = GET_ORPHAN_BLOCKS(im->ino_num);
559 
560 	/*
561 	 * we don't need to do spin_lock(&im->ino_lock) here, since all the
562 	 * orphan inode operations are covered under f2fs_lock_op().
563 	 * And, spin_lock should be avoided due to page operations below.
564 	 */
565 	head = &im->ino_list;
566 
567 	/* loop for each orphan inode entry and write them in Jornal block */
568 	list_for_each_entry(orphan, head, list) {
569 		if (!page) {
570 			page = grab_meta_page(sbi, start_blk++);
571 			orphan_blk =
572 				(struct f2fs_orphan_block *)page_address(page);
573 			memset(orphan_blk, 0, sizeof(*orphan_blk));
574 		}
575 
576 		orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
577 
578 		if (nentries == F2FS_ORPHANS_PER_BLOCK) {
579 			/*
580 			 * an orphan block is full of 1020 entries,
581 			 * then we need to flush current orphan blocks
582 			 * and bring another one in memory
583 			 */
584 			orphan_blk->blk_addr = cpu_to_le16(index);
585 			orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
586 			orphan_blk->entry_count = cpu_to_le32(nentries);
587 			set_page_dirty(page);
588 			f2fs_put_page(page, 1);
589 			index++;
590 			nentries = 0;
591 			page = NULL;
592 		}
593 	}
594 
595 	if (page) {
596 		orphan_blk->blk_addr = cpu_to_le16(index);
597 		orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
598 		orphan_blk->entry_count = cpu_to_le32(nentries);
599 		set_page_dirty(page);
600 		f2fs_put_page(page, 1);
601 	}
602 }
603 
604 static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
605 				block_t cp_addr, unsigned long long *version)
606 {
607 	struct page *cp_page_1, *cp_page_2 = NULL;
608 	unsigned long blk_size = sbi->blocksize;
609 	struct f2fs_checkpoint *cp_block;
610 	unsigned long long cur_version = 0, pre_version = 0;
611 	size_t crc_offset;
612 	__u32 crc = 0;
613 
614 	/* Read the 1st cp block in this CP pack */
615 	cp_page_1 = get_meta_page(sbi, cp_addr);
616 
617 	/* get the version number */
618 	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_1);
619 	crc_offset = le32_to_cpu(cp_block->checksum_offset);
620 	if (crc_offset >= blk_size)
621 		goto invalid_cp1;
622 
623 	crc = le32_to_cpu(*((__le32 *)((unsigned char *)cp_block + crc_offset)));
624 	if (!f2fs_crc_valid(crc, cp_block, crc_offset))
625 		goto invalid_cp1;
626 
627 	pre_version = cur_cp_version(cp_block);
628 
629 	/* Read the 2nd cp block in this CP pack */
630 	cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1;
631 	cp_page_2 = get_meta_page(sbi, cp_addr);
632 
633 	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_2);
634 	crc_offset = le32_to_cpu(cp_block->checksum_offset);
635 	if (crc_offset >= blk_size)
636 		goto invalid_cp2;
637 
638 	crc = le32_to_cpu(*((__le32 *)((unsigned char *)cp_block + crc_offset)));
639 	if (!f2fs_crc_valid(crc, cp_block, crc_offset))
640 		goto invalid_cp2;
641 
642 	cur_version = cur_cp_version(cp_block);
643 
644 	if (cur_version == pre_version) {
645 		*version = cur_version;
646 		f2fs_put_page(cp_page_2, 1);
647 		return cp_page_1;
648 	}
649 invalid_cp2:
650 	f2fs_put_page(cp_page_2, 1);
651 invalid_cp1:
652 	f2fs_put_page(cp_page_1, 1);
653 	return NULL;
654 }
655 
656 int get_valid_checkpoint(struct f2fs_sb_info *sbi)
657 {
658 	struct f2fs_checkpoint *cp_block;
659 	struct f2fs_super_block *fsb = sbi->raw_super;
660 	struct page *cp1, *cp2, *cur_page;
661 	unsigned long blk_size = sbi->blocksize;
662 	unsigned long long cp1_version = 0, cp2_version = 0;
663 	unsigned long long cp_start_blk_no;
664 	unsigned int cp_blks = 1 + __cp_payload(sbi);
665 	block_t cp_blk_no;
666 	int i;
667 
668 	sbi->ckpt = kzalloc(cp_blks * blk_size, GFP_KERNEL);
669 	if (!sbi->ckpt)
670 		return -ENOMEM;
671 	/*
672 	 * Finding out valid cp block involves read both
673 	 * sets( cp pack1 and cp pack 2)
674 	 */
675 	cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
676 	cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
677 
678 	/* The second checkpoint pack should start at the next segment */
679 	cp_start_blk_no += ((unsigned long long)1) <<
680 				le32_to_cpu(fsb->log_blocks_per_seg);
681 	cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
682 
683 	if (cp1 && cp2) {
684 		if (ver_after(cp2_version, cp1_version))
685 			cur_page = cp2;
686 		else
687 			cur_page = cp1;
688 	} else if (cp1) {
689 		cur_page = cp1;
690 	} else if (cp2) {
691 		cur_page = cp2;
692 	} else {
693 		goto fail_no_cp;
694 	}
695 
696 	cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
697 	memcpy(sbi->ckpt, cp_block, blk_size);
698 
699 	if (cp_blks <= 1)
700 		goto done;
701 
702 	cp_blk_no = le32_to_cpu(fsb->cp_blkaddr);
703 	if (cur_page == cp2)
704 		cp_blk_no += 1 << le32_to_cpu(fsb->log_blocks_per_seg);
705 
706 	for (i = 1; i < cp_blks; i++) {
707 		void *sit_bitmap_ptr;
708 		unsigned char *ckpt = (unsigned char *)sbi->ckpt;
709 
710 		cur_page = get_meta_page(sbi, cp_blk_no + i);
711 		sit_bitmap_ptr = page_address(cur_page);
712 		memcpy(ckpt + i * blk_size, sit_bitmap_ptr, blk_size);
713 		f2fs_put_page(cur_page, 1);
714 	}
715 done:
716 	f2fs_put_page(cp1, 1);
717 	f2fs_put_page(cp2, 1);
718 	return 0;
719 
720 fail_no_cp:
721 	kfree(sbi->ckpt);
722 	return -EINVAL;
723 }
724 
725 static void __add_dirty_inode(struct inode *inode)
726 {
727 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
728 	struct f2fs_inode_info *fi = F2FS_I(inode);
729 
730 	if (is_inode_flag_set(fi, FI_DIRTY_DIR))
731 		return;
732 
733 	set_inode_flag(fi, FI_DIRTY_DIR);
734 	list_add_tail(&fi->dirty_list, &sbi->dir_inode_list);
735 	stat_inc_dirty_dir(sbi);
736 	return;
737 }
738 
739 static void __remove_dirty_inode(struct inode *inode)
740 {
741 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
742 	struct f2fs_inode_info *fi = F2FS_I(inode);
743 
744 	if (get_dirty_pages(inode) ||
745 			!is_inode_flag_set(F2FS_I(inode), FI_DIRTY_DIR))
746 		return;
747 
748 	list_del_init(&fi->dirty_list);
749 	clear_inode_flag(fi, FI_DIRTY_DIR);
750 	stat_dec_dirty_dir(sbi);
751 }
752 
753 void update_dirty_page(struct inode *inode, struct page *page)
754 {
755 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
756 
757 	if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
758 			!S_ISLNK(inode->i_mode))
759 		return;
760 
761 	if (!S_ISDIR(inode->i_mode)) {
762 		inode_inc_dirty_pages(inode);
763 		goto out;
764 	}
765 
766 	spin_lock(&sbi->dir_inode_lock);
767 	__add_dirty_inode(inode);
768 	inode_inc_dirty_pages(inode);
769 	spin_unlock(&sbi->dir_inode_lock);
770 
771 out:
772 	SetPagePrivate(page);
773 	f2fs_trace_pid(page);
774 }
775 
776 void add_dirty_dir_inode(struct inode *inode)
777 {
778 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
779 
780 	spin_lock(&sbi->dir_inode_lock);
781 	__add_dirty_inode(inode);
782 	spin_unlock(&sbi->dir_inode_lock);
783 }
784 
785 void remove_dirty_dir_inode(struct inode *inode)
786 {
787 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
788 	struct f2fs_inode_info *fi = F2FS_I(inode);
789 
790 	if (!S_ISDIR(inode->i_mode))
791 		return;
792 
793 	spin_lock(&sbi->dir_inode_lock);
794 	__remove_dirty_inode(inode);
795 	spin_unlock(&sbi->dir_inode_lock);
796 
797 	/* Only from the recovery routine */
798 	if (is_inode_flag_set(fi, FI_DELAY_IPUT)) {
799 		clear_inode_flag(fi, FI_DELAY_IPUT);
800 		iput(inode);
801 	}
802 }
803 
804 void sync_dirty_dir_inodes(struct f2fs_sb_info *sbi)
805 {
806 	struct list_head *head;
807 	struct inode *inode;
808 	struct f2fs_inode_info *fi;
809 retry:
810 	if (unlikely(f2fs_cp_error(sbi)))
811 		return;
812 
813 	spin_lock(&sbi->dir_inode_lock);
814 
815 	head = &sbi->dir_inode_list;
816 	if (list_empty(head)) {
817 		spin_unlock(&sbi->dir_inode_lock);
818 		return;
819 	}
820 	fi = list_entry(head->next, struct f2fs_inode_info, dirty_list);
821 	inode = igrab(&fi->vfs_inode);
822 	spin_unlock(&sbi->dir_inode_lock);
823 	if (inode) {
824 		filemap_fdatawrite(inode->i_mapping);
825 		iput(inode);
826 	} else {
827 		/*
828 		 * We should submit bio, since it exists several
829 		 * wribacking dentry pages in the freeing inode.
830 		 */
831 		f2fs_submit_merged_bio(sbi, DATA, WRITE);
832 		cond_resched();
833 	}
834 	goto retry;
835 }
836 
837 /*
838  * Freeze all the FS-operations for checkpoint.
839  */
840 static int block_operations(struct f2fs_sb_info *sbi)
841 {
842 	struct writeback_control wbc = {
843 		.sync_mode = WB_SYNC_ALL,
844 		.nr_to_write = LONG_MAX,
845 		.for_reclaim = 0,
846 	};
847 	struct blk_plug plug;
848 	int err = 0;
849 
850 	blk_start_plug(&plug);
851 
852 retry_flush_dents:
853 	f2fs_lock_all(sbi);
854 	/* write all the dirty dentry pages */
855 	if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
856 		f2fs_unlock_all(sbi);
857 		sync_dirty_dir_inodes(sbi);
858 		if (unlikely(f2fs_cp_error(sbi))) {
859 			err = -EIO;
860 			goto out;
861 		}
862 		goto retry_flush_dents;
863 	}
864 
865 	/*
866 	 * POR: we should ensure that there are no dirty node pages
867 	 * until finishing nat/sit flush.
868 	 */
869 retry_flush_nodes:
870 	down_write(&sbi->node_write);
871 
872 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
873 		up_write(&sbi->node_write);
874 		sync_node_pages(sbi, 0, &wbc);
875 		if (unlikely(f2fs_cp_error(sbi))) {
876 			f2fs_unlock_all(sbi);
877 			err = -EIO;
878 			goto out;
879 		}
880 		goto retry_flush_nodes;
881 	}
882 out:
883 	blk_finish_plug(&plug);
884 	return err;
885 }
886 
887 static void unblock_operations(struct f2fs_sb_info *sbi)
888 {
889 	up_write(&sbi->node_write);
890 	f2fs_unlock_all(sbi);
891 }
892 
893 static void wait_on_all_pages_writeback(struct f2fs_sb_info *sbi)
894 {
895 	DEFINE_WAIT(wait);
896 
897 	for (;;) {
898 		prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
899 
900 		if (!get_pages(sbi, F2FS_WRITEBACK))
901 			break;
902 
903 		io_schedule();
904 	}
905 	finish_wait(&sbi->cp_wait, &wait);
906 }
907 
908 static void do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
909 {
910 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
911 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_WARM_NODE);
912 	struct f2fs_nm_info *nm_i = NM_I(sbi);
913 	unsigned long orphan_num = sbi->im[ORPHAN_INO].ino_num;
914 	nid_t last_nid = nm_i->next_scan_nid;
915 	block_t start_blk;
916 	unsigned int data_sum_blocks, orphan_blocks;
917 	__u32 crc32 = 0;
918 	int i;
919 	int cp_payload_blks = __cp_payload(sbi);
920 	block_t discard_blk = NEXT_FREE_BLKADDR(sbi, curseg);
921 	bool invalidate = false;
922 
923 	/*
924 	 * This avoids to conduct wrong roll-forward operations and uses
925 	 * metapages, so should be called prior to sync_meta_pages below.
926 	 */
927 	if (discard_next_dnode(sbi, discard_blk))
928 		invalidate = true;
929 
930 	/* Flush all the NAT/SIT pages */
931 	while (get_pages(sbi, F2FS_DIRTY_META)) {
932 		sync_meta_pages(sbi, META, LONG_MAX);
933 		if (unlikely(f2fs_cp_error(sbi)))
934 			return;
935 	}
936 
937 	next_free_nid(sbi, &last_nid);
938 
939 	/*
940 	 * modify checkpoint
941 	 * version number is already updated
942 	 */
943 	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi));
944 	ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
945 	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
946 	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
947 		ckpt->cur_node_segno[i] =
948 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
949 		ckpt->cur_node_blkoff[i] =
950 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
951 		ckpt->alloc_type[i + CURSEG_HOT_NODE] =
952 				curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
953 	}
954 	for (i = 0; i < NR_CURSEG_DATA_TYPE; i++) {
955 		ckpt->cur_data_segno[i] =
956 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
957 		ckpt->cur_data_blkoff[i] =
958 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
959 		ckpt->alloc_type[i + CURSEG_HOT_DATA] =
960 				curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
961 	}
962 
963 	ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
964 	ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
965 	ckpt->next_free_nid = cpu_to_le32(last_nid);
966 
967 	/* 2 cp  + n data seg summary + orphan inode blocks */
968 	data_sum_blocks = npages_for_summary_flush(sbi, false);
969 	if (data_sum_blocks < NR_CURSEG_DATA_TYPE)
970 		set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
971 	else
972 		clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
973 
974 	orphan_blocks = GET_ORPHAN_BLOCKS(orphan_num);
975 	ckpt->cp_pack_start_sum = cpu_to_le32(1 + cp_payload_blks +
976 			orphan_blocks);
977 
978 	if (__remain_node_summaries(cpc->reason))
979 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS+
980 				cp_payload_blks + data_sum_blocks +
981 				orphan_blocks + NR_CURSEG_NODE_TYPE);
982 	else
983 		ckpt->cp_pack_total_block_count = cpu_to_le32(F2FS_CP_PACKS +
984 				cp_payload_blks + data_sum_blocks +
985 				orphan_blocks);
986 
987 	if (cpc->reason == CP_UMOUNT)
988 		set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
989 	else
990 		clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
991 
992 	if (cpc->reason == CP_FASTBOOT)
993 		set_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
994 	else
995 		clear_ckpt_flags(ckpt, CP_FASTBOOT_FLAG);
996 
997 	if (orphan_num)
998 		set_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
999 	else
1000 		clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
1001 
1002 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
1003 		set_ckpt_flags(ckpt, CP_FSCK_FLAG);
1004 
1005 	/* update SIT/NAT bitmap */
1006 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
1007 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
1008 
1009 	crc32 = f2fs_crc32(ckpt, le32_to_cpu(ckpt->checksum_offset));
1010 	*((__le32 *)((unsigned char *)ckpt +
1011 				le32_to_cpu(ckpt->checksum_offset)))
1012 				= cpu_to_le32(crc32);
1013 
1014 	start_blk = __start_cp_addr(sbi);
1015 
1016 	/* need to wait for end_io results */
1017 	wait_on_all_pages_writeback(sbi);
1018 	if (unlikely(f2fs_cp_error(sbi)))
1019 		return;
1020 
1021 	/* write out checkpoint buffer at block 0 */
1022 	update_meta_page(sbi, ckpt, start_blk++);
1023 
1024 	for (i = 1; i < 1 + cp_payload_blks; i++)
1025 		update_meta_page(sbi, (char *)ckpt + i * F2FS_BLKSIZE,
1026 							start_blk++);
1027 
1028 	if (orphan_num) {
1029 		write_orphan_inodes(sbi, start_blk);
1030 		start_blk += orphan_blocks;
1031 	}
1032 
1033 	write_data_summaries(sbi, start_blk);
1034 	start_blk += data_sum_blocks;
1035 	if (__remain_node_summaries(cpc->reason)) {
1036 		write_node_summaries(sbi, start_blk);
1037 		start_blk += NR_CURSEG_NODE_TYPE;
1038 	}
1039 
1040 	/* writeout checkpoint block */
1041 	update_meta_page(sbi, ckpt, start_blk);
1042 
1043 	/* wait for previous submitted node/meta pages writeback */
1044 	wait_on_all_pages_writeback(sbi);
1045 
1046 	if (unlikely(f2fs_cp_error(sbi)))
1047 		return;
1048 
1049 	filemap_fdatawait_range(NODE_MAPPING(sbi), 0, LONG_MAX);
1050 	filemap_fdatawait_range(META_MAPPING(sbi), 0, LONG_MAX);
1051 
1052 	/* update user_block_counts */
1053 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1054 	sbi->alloc_valid_block_count = 0;
1055 
1056 	/* Here, we only have one bio having CP pack */
1057 	sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
1058 
1059 	/* wait for previous submitted meta pages writeback */
1060 	wait_on_all_pages_writeback(sbi);
1061 
1062 	/*
1063 	 * invalidate meta page which is used temporarily for zeroing out
1064 	 * block at the end of warm node chain.
1065 	 */
1066 	if (invalidate)
1067 		invalidate_mapping_pages(META_MAPPING(sbi), discard_blk,
1068 								discard_blk);
1069 
1070 	release_ino_entry(sbi);
1071 
1072 	if (unlikely(f2fs_cp_error(sbi)))
1073 		return;
1074 
1075 	clear_prefree_segments(sbi, cpc);
1076 	clear_sbi_flag(sbi, SBI_IS_DIRTY);
1077 }
1078 
1079 /*
1080  * We guarantee that this checkpoint procedure will not fail.
1081  */
1082 void write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1083 {
1084 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1085 	unsigned long long ckpt_ver;
1086 
1087 	mutex_lock(&sbi->cp_mutex);
1088 
1089 	if (!is_sbi_flag_set(sbi, SBI_IS_DIRTY) &&
1090 		(cpc->reason == CP_FASTBOOT || cpc->reason == CP_SYNC ||
1091 		(cpc->reason == CP_DISCARD && !sbi->discard_blks)))
1092 		goto out;
1093 	if (unlikely(f2fs_cp_error(sbi)))
1094 		goto out;
1095 	if (f2fs_readonly(sbi->sb))
1096 		goto out;
1097 
1098 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "start block_ops");
1099 
1100 	if (block_operations(sbi))
1101 		goto out;
1102 
1103 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish block_ops");
1104 
1105 	f2fs_submit_merged_bio(sbi, DATA, WRITE);
1106 	f2fs_submit_merged_bio(sbi, NODE, WRITE);
1107 	f2fs_submit_merged_bio(sbi, META, WRITE);
1108 
1109 	/*
1110 	 * update checkpoint pack index
1111 	 * Increase the version number so that
1112 	 * SIT entries and seg summaries are written at correct place
1113 	 */
1114 	ckpt_ver = cur_cp_version(ckpt);
1115 	ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
1116 
1117 	/* write cached NAT/SIT entries to NAT/SIT area */
1118 	flush_nat_entries(sbi);
1119 	flush_sit_entries(sbi, cpc);
1120 
1121 	/* unlock all the fs_lock[] in do_checkpoint() */
1122 	do_checkpoint(sbi, cpc);
1123 
1124 	unblock_operations(sbi);
1125 	stat_inc_cp_count(sbi->stat_info);
1126 
1127 	if (cpc->reason == CP_RECOVERY)
1128 		f2fs_msg(sbi->sb, KERN_NOTICE,
1129 			"checkpoint: version = %llx", ckpt_ver);
1130 
1131 	/* do checkpoint periodically */
1132 	sbi->cp_expires = round_jiffies_up(jiffies + HZ * sbi->cp_interval);
1133 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint");
1134 out:
1135 	mutex_unlock(&sbi->cp_mutex);
1136 }
1137 
1138 void init_ino_entry_info(struct f2fs_sb_info *sbi)
1139 {
1140 	int i;
1141 
1142 	for (i = 0; i < MAX_INO_ENTRY; i++) {
1143 		struct inode_management *im = &sbi->im[i];
1144 
1145 		INIT_RADIX_TREE(&im->ino_root, GFP_ATOMIC);
1146 		spin_lock_init(&im->ino_lock);
1147 		INIT_LIST_HEAD(&im->ino_list);
1148 		im->ino_num = 0;
1149 	}
1150 
1151 	sbi->max_orphans = (sbi->blocks_per_seg - F2FS_CP_PACKS -
1152 			NR_CURSEG_TYPE - __cp_payload(sbi)) *
1153 				F2FS_ORPHANS_PER_BLOCK;
1154 }
1155 
1156 int __init create_checkpoint_caches(void)
1157 {
1158 	ino_entry_slab = f2fs_kmem_cache_create("f2fs_ino_entry",
1159 			sizeof(struct ino_entry));
1160 	if (!ino_entry_slab)
1161 		return -ENOMEM;
1162 	inode_entry_slab = f2fs_kmem_cache_create("f2fs_inode_entry",
1163 			sizeof(struct inode_entry));
1164 	if (!inode_entry_slab) {
1165 		kmem_cache_destroy(ino_entry_slab);
1166 		return -ENOMEM;
1167 	}
1168 	return 0;
1169 }
1170 
1171 void destroy_checkpoint_caches(void)
1172 {
1173 	kmem_cache_destroy(ino_entry_slab);
1174 	kmem_cache_destroy(inode_entry_slab);
1175 }
1176