xref: /openbmc/linux/fs/f2fs/checkpoint.c (revision 7bd59381c82defe19875284c48b1ac9dacd16e8f)
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/events/f2fs.h>
24 
25 static struct kmem_cache *orphan_entry_slab;
26 static struct kmem_cache *inode_entry_slab;
27 
28 /*
29  * We guarantee no failure on the returned page.
30  */
31 struct page *grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
32 {
33 	struct address_space *mapping = sbi->meta_inode->i_mapping;
34 	struct page *page = NULL;
35 repeat:
36 	page = grab_cache_page(mapping, index);
37 	if (!page) {
38 		cond_resched();
39 		goto repeat;
40 	}
41 
42 	/* We wait writeback only inside grab_meta_page() */
43 	wait_on_page_writeback(page);
44 	SetPageUptodate(page);
45 	return page;
46 }
47 
48 /*
49  * We guarantee no failure on the returned page.
50  */
51 struct page *get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
52 {
53 	struct address_space *mapping = sbi->meta_inode->i_mapping;
54 	struct page *page;
55 repeat:
56 	page = grab_cache_page(mapping, index);
57 	if (!page) {
58 		cond_resched();
59 		goto repeat;
60 	}
61 	if (PageUptodate(page))
62 		goto out;
63 
64 	if (f2fs_readpage(sbi, page, index, READ_SYNC))
65 		goto repeat;
66 
67 	lock_page(page);
68 	if (page->mapping != mapping) {
69 		f2fs_put_page(page, 1);
70 		goto repeat;
71 	}
72 out:
73 	mark_page_accessed(page);
74 	return page;
75 }
76 
77 static int f2fs_write_meta_page(struct page *page,
78 				struct writeback_control *wbc)
79 {
80 	struct inode *inode = page->mapping->host;
81 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
82 
83 	/* Should not write any meta pages, if any IO error was occurred */
84 	if (wbc->for_reclaim || sbi->por_doing ||
85 			is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ERROR_FLAG)) {
86 		dec_page_count(sbi, F2FS_DIRTY_META);
87 		wbc->pages_skipped++;
88 		set_page_dirty(page);
89 		return AOP_WRITEPAGE_ACTIVATE;
90 	}
91 
92 	wait_on_page_writeback(page);
93 
94 	write_meta_page(sbi, page);
95 	dec_page_count(sbi, F2FS_DIRTY_META);
96 	unlock_page(page);
97 	return 0;
98 }
99 
100 static int f2fs_write_meta_pages(struct address_space *mapping,
101 				struct writeback_control *wbc)
102 {
103 	struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
104 	struct block_device *bdev = sbi->sb->s_bdev;
105 	long written;
106 
107 	if (wbc->for_kupdate)
108 		return 0;
109 
110 	if (get_pages(sbi, F2FS_DIRTY_META) == 0)
111 		return 0;
112 
113 	/* if mounting is failed, skip writing node pages */
114 	mutex_lock(&sbi->cp_mutex);
115 	written = sync_meta_pages(sbi, META, bio_get_nr_vecs(bdev));
116 	mutex_unlock(&sbi->cp_mutex);
117 	wbc->nr_to_write -= written;
118 	return 0;
119 }
120 
121 long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
122 						long nr_to_write)
123 {
124 	struct address_space *mapping = sbi->meta_inode->i_mapping;
125 	pgoff_t index = 0, end = LONG_MAX;
126 	struct pagevec pvec;
127 	long nwritten = 0;
128 	struct writeback_control wbc = {
129 		.for_reclaim = 0,
130 	};
131 
132 	pagevec_init(&pvec, 0);
133 
134 	while (index <= end) {
135 		int i, nr_pages;
136 		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
137 				PAGECACHE_TAG_DIRTY,
138 				min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
139 		if (nr_pages == 0)
140 			break;
141 
142 		for (i = 0; i < nr_pages; i++) {
143 			struct page *page = pvec.pages[i];
144 			lock_page(page);
145 			BUG_ON(page->mapping != mapping);
146 			BUG_ON(!PageDirty(page));
147 			clear_page_dirty_for_io(page);
148 			if (f2fs_write_meta_page(page, &wbc)) {
149 				unlock_page(page);
150 				break;
151 			}
152 			if (nwritten++ >= nr_to_write)
153 				break;
154 		}
155 		pagevec_release(&pvec);
156 		cond_resched();
157 	}
158 
159 	if (nwritten)
160 		f2fs_submit_bio(sbi, type, nr_to_write == LONG_MAX);
161 
162 	return nwritten;
163 }
164 
165 static int f2fs_set_meta_page_dirty(struct page *page)
166 {
167 	struct address_space *mapping = page->mapping;
168 	struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
169 
170 	SetPageUptodate(page);
171 	if (!PageDirty(page)) {
172 		__set_page_dirty_nobuffers(page);
173 		inc_page_count(sbi, F2FS_DIRTY_META);
174 		return 1;
175 	}
176 	return 0;
177 }
178 
179 const struct address_space_operations f2fs_meta_aops = {
180 	.writepage	= f2fs_write_meta_page,
181 	.writepages	= f2fs_write_meta_pages,
182 	.set_page_dirty	= f2fs_set_meta_page_dirty,
183 };
184 
185 int acquire_orphan_inode(struct f2fs_sb_info *sbi)
186 {
187 	unsigned int max_orphans;
188 	int err = 0;
189 
190 	/*
191 	 * considering 512 blocks in a segment 5 blocks are needed for cp
192 	 * and log segment summaries. Remaining blocks are used to keep
193 	 * orphan entries with the limitation one reserved segment
194 	 * for cp pack we can have max 1020*507 orphan entries
195 	 */
196 	max_orphans = (sbi->blocks_per_seg - 5) * F2FS_ORPHANS_PER_BLOCK;
197 	mutex_lock(&sbi->orphan_inode_mutex);
198 	if (sbi->n_orphans >= max_orphans)
199 		err = -ENOSPC;
200 	else
201 		sbi->n_orphans++;
202 	mutex_unlock(&sbi->orphan_inode_mutex);
203 	return err;
204 }
205 
206 void release_orphan_inode(struct f2fs_sb_info *sbi)
207 {
208 	mutex_lock(&sbi->orphan_inode_mutex);
209 	BUG_ON(sbi->n_orphans == 0);
210 	sbi->n_orphans--;
211 	mutex_unlock(&sbi->orphan_inode_mutex);
212 }
213 
214 void add_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
215 {
216 	struct list_head *head, *this;
217 	struct orphan_inode_entry *new = NULL, *orphan = NULL;
218 
219 	mutex_lock(&sbi->orphan_inode_mutex);
220 	head = &sbi->orphan_inode_list;
221 	list_for_each(this, head) {
222 		orphan = list_entry(this, struct orphan_inode_entry, list);
223 		if (orphan->ino == ino)
224 			goto out;
225 		if (orphan->ino > ino)
226 			break;
227 		orphan = NULL;
228 	}
229 
230 	new = f2fs_kmem_cache_alloc(orphan_entry_slab, GFP_ATOMIC);
231 	new->ino = ino;
232 
233 	/* add new_oentry into list which is sorted by inode number */
234 	if (orphan)
235 		list_add(&new->list, this->prev);
236 	else
237 		list_add_tail(&new->list, head);
238 out:
239 	mutex_unlock(&sbi->orphan_inode_mutex);
240 }
241 
242 void remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
243 {
244 	struct list_head *head;
245 	struct orphan_inode_entry *orphan;
246 
247 	mutex_lock(&sbi->orphan_inode_mutex);
248 	head = &sbi->orphan_inode_list;
249 	list_for_each_entry(orphan, head, list) {
250 		if (orphan->ino == ino) {
251 			list_del(&orphan->list);
252 			kmem_cache_free(orphan_entry_slab, orphan);
253 			BUG_ON(sbi->n_orphans == 0);
254 			sbi->n_orphans--;
255 			break;
256 		}
257 	}
258 	mutex_unlock(&sbi->orphan_inode_mutex);
259 }
260 
261 static void recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
262 {
263 	struct inode *inode = f2fs_iget(sbi->sb, ino);
264 	BUG_ON(IS_ERR(inode));
265 	clear_nlink(inode);
266 
267 	/* truncate all the data during iput */
268 	iput(inode);
269 }
270 
271 int recover_orphan_inodes(struct f2fs_sb_info *sbi)
272 {
273 	block_t start_blk, orphan_blkaddr, i, j;
274 
275 	if (!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG))
276 		return 0;
277 
278 	sbi->por_doing = 1;
279 	start_blk = __start_cp_addr(sbi) + 1;
280 	orphan_blkaddr = __start_sum_addr(sbi) - 1;
281 
282 	for (i = 0; i < orphan_blkaddr; i++) {
283 		struct page *page = get_meta_page(sbi, start_blk + i);
284 		struct f2fs_orphan_block *orphan_blk;
285 
286 		orphan_blk = (struct f2fs_orphan_block *)page_address(page);
287 		for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
288 			nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
289 			recover_orphan_inode(sbi, ino);
290 		}
291 		f2fs_put_page(page, 1);
292 	}
293 	/* clear Orphan Flag */
294 	clear_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG);
295 	sbi->por_doing = 0;
296 	return 0;
297 }
298 
299 static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
300 {
301 	struct list_head *head, *this, *next;
302 	struct f2fs_orphan_block *orphan_blk = NULL;
303 	struct page *page = NULL;
304 	unsigned int nentries = 0;
305 	unsigned short index = 1;
306 	unsigned short orphan_blocks;
307 
308 	orphan_blocks = (unsigned short)((sbi->n_orphans +
309 		(F2FS_ORPHANS_PER_BLOCK - 1)) / F2FS_ORPHANS_PER_BLOCK);
310 
311 	mutex_lock(&sbi->orphan_inode_mutex);
312 	head = &sbi->orphan_inode_list;
313 
314 	/* loop for each orphan inode entry and write them in Jornal block */
315 	list_for_each_safe(this, next, head) {
316 		struct orphan_inode_entry *orphan;
317 
318 		orphan = list_entry(this, struct orphan_inode_entry, list);
319 
320 		if (nentries == F2FS_ORPHANS_PER_BLOCK) {
321 			/*
322 			 * an orphan block is full of 1020 entries,
323 			 * then we need to flush current orphan blocks
324 			 * and bring another one in memory
325 			 */
326 			orphan_blk->blk_addr = cpu_to_le16(index);
327 			orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
328 			orphan_blk->entry_count = cpu_to_le32(nentries);
329 			set_page_dirty(page);
330 			f2fs_put_page(page, 1);
331 			index++;
332 			start_blk++;
333 			nentries = 0;
334 			page = NULL;
335 		}
336 		if (page)
337 			goto page_exist;
338 
339 		page = grab_meta_page(sbi, start_blk);
340 		orphan_blk = (struct f2fs_orphan_block *)page_address(page);
341 		memset(orphan_blk, 0, sizeof(*orphan_blk));
342 page_exist:
343 		orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
344 	}
345 	if (!page)
346 		goto end;
347 
348 	orphan_blk->blk_addr = cpu_to_le16(index);
349 	orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
350 	orphan_blk->entry_count = cpu_to_le32(nentries);
351 	set_page_dirty(page);
352 	f2fs_put_page(page, 1);
353 end:
354 	mutex_unlock(&sbi->orphan_inode_mutex);
355 }
356 
357 static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
358 				block_t cp_addr, unsigned long long *version)
359 {
360 	struct page *cp_page_1, *cp_page_2 = NULL;
361 	unsigned long blk_size = sbi->blocksize;
362 	struct f2fs_checkpoint *cp_block;
363 	unsigned long long cur_version = 0, pre_version = 0;
364 	size_t crc_offset;
365 	__u32 crc = 0;
366 
367 	/* Read the 1st cp block in this CP pack */
368 	cp_page_1 = get_meta_page(sbi, cp_addr);
369 
370 	/* get the version number */
371 	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_1);
372 	crc_offset = le32_to_cpu(cp_block->checksum_offset);
373 	if (crc_offset >= blk_size)
374 		goto invalid_cp1;
375 
376 	crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
377 	if (!f2fs_crc_valid(crc, cp_block, crc_offset))
378 		goto invalid_cp1;
379 
380 	pre_version = cur_cp_version(cp_block);
381 
382 	/* Read the 2nd cp block in this CP pack */
383 	cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1;
384 	cp_page_2 = get_meta_page(sbi, cp_addr);
385 
386 	cp_block = (struct f2fs_checkpoint *)page_address(cp_page_2);
387 	crc_offset = le32_to_cpu(cp_block->checksum_offset);
388 	if (crc_offset >= blk_size)
389 		goto invalid_cp2;
390 
391 	crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
392 	if (!f2fs_crc_valid(crc, cp_block, crc_offset))
393 		goto invalid_cp2;
394 
395 	cur_version = cur_cp_version(cp_block);
396 
397 	if (cur_version == pre_version) {
398 		*version = cur_version;
399 		f2fs_put_page(cp_page_2, 1);
400 		return cp_page_1;
401 	}
402 invalid_cp2:
403 	f2fs_put_page(cp_page_2, 1);
404 invalid_cp1:
405 	f2fs_put_page(cp_page_1, 1);
406 	return NULL;
407 }
408 
409 int get_valid_checkpoint(struct f2fs_sb_info *sbi)
410 {
411 	struct f2fs_checkpoint *cp_block;
412 	struct f2fs_super_block *fsb = sbi->raw_super;
413 	struct page *cp1, *cp2, *cur_page;
414 	unsigned long blk_size = sbi->blocksize;
415 	unsigned long long cp1_version = 0, cp2_version = 0;
416 	unsigned long long cp_start_blk_no;
417 
418 	sbi->ckpt = kzalloc(blk_size, GFP_KERNEL);
419 	if (!sbi->ckpt)
420 		return -ENOMEM;
421 	/*
422 	 * Finding out valid cp block involves read both
423 	 * sets( cp pack1 and cp pack 2)
424 	 */
425 	cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
426 	cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
427 
428 	/* The second checkpoint pack should start at the next segment */
429 	cp_start_blk_no += 1 << le32_to_cpu(fsb->log_blocks_per_seg);
430 	cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
431 
432 	if (cp1 && cp2) {
433 		if (ver_after(cp2_version, cp1_version))
434 			cur_page = cp2;
435 		else
436 			cur_page = cp1;
437 	} else if (cp1) {
438 		cur_page = cp1;
439 	} else if (cp2) {
440 		cur_page = cp2;
441 	} else {
442 		goto fail_no_cp;
443 	}
444 
445 	cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
446 	memcpy(sbi->ckpt, cp_block, blk_size);
447 
448 	f2fs_put_page(cp1, 1);
449 	f2fs_put_page(cp2, 1);
450 	return 0;
451 
452 fail_no_cp:
453 	kfree(sbi->ckpt);
454 	return -EINVAL;
455 }
456 
457 static int __add_dirty_inode(struct inode *inode, struct dir_inode_entry *new)
458 {
459 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
460 	struct list_head *head = &sbi->dir_inode_list;
461 	struct list_head *this;
462 
463 	list_for_each(this, head) {
464 		struct dir_inode_entry *entry;
465 		entry = list_entry(this, struct dir_inode_entry, list);
466 		if (entry->inode == inode)
467 			return -EEXIST;
468 	}
469 	list_add_tail(&new->list, head);
470 #ifdef CONFIG_F2FS_STAT_FS
471 	sbi->n_dirty_dirs++;
472 #endif
473 	return 0;
474 }
475 
476 void set_dirty_dir_page(struct inode *inode, struct page *page)
477 {
478 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
479 	struct dir_inode_entry *new;
480 
481 	if (!S_ISDIR(inode->i_mode))
482 		return;
483 
484 	new = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
485 	new->inode = inode;
486 	INIT_LIST_HEAD(&new->list);
487 
488 	spin_lock(&sbi->dir_inode_lock);
489 	if (__add_dirty_inode(inode, new))
490 		kmem_cache_free(inode_entry_slab, new);
491 
492 	inc_page_count(sbi, F2FS_DIRTY_DENTS);
493 	inode_inc_dirty_dents(inode);
494 	SetPagePrivate(page);
495 	spin_unlock(&sbi->dir_inode_lock);
496 }
497 
498 void add_dirty_dir_inode(struct inode *inode)
499 {
500 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
501 	struct dir_inode_entry *new =
502 			f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
503 
504 	new->inode = inode;
505 	INIT_LIST_HEAD(&new->list);
506 
507 	spin_lock(&sbi->dir_inode_lock);
508 	if (__add_dirty_inode(inode, new))
509 		kmem_cache_free(inode_entry_slab, new);
510 	spin_unlock(&sbi->dir_inode_lock);
511 }
512 
513 void remove_dirty_dir_inode(struct inode *inode)
514 {
515 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
516 	struct list_head *head = &sbi->dir_inode_list;
517 	struct list_head *this;
518 
519 	if (!S_ISDIR(inode->i_mode))
520 		return;
521 
522 	spin_lock(&sbi->dir_inode_lock);
523 	if (atomic_read(&F2FS_I(inode)->dirty_dents)) {
524 		spin_unlock(&sbi->dir_inode_lock);
525 		return;
526 	}
527 
528 	list_for_each(this, head) {
529 		struct dir_inode_entry *entry;
530 		entry = list_entry(this, struct dir_inode_entry, list);
531 		if (entry->inode == inode) {
532 			list_del(&entry->list);
533 			kmem_cache_free(inode_entry_slab, entry);
534 #ifdef CONFIG_F2FS_STAT_FS
535 			sbi->n_dirty_dirs--;
536 #endif
537 			break;
538 		}
539 	}
540 	spin_unlock(&sbi->dir_inode_lock);
541 
542 	/* Only from the recovery routine */
543 	if (is_inode_flag_set(F2FS_I(inode), FI_DELAY_IPUT)) {
544 		clear_inode_flag(F2FS_I(inode), FI_DELAY_IPUT);
545 		iput(inode);
546 	}
547 }
548 
549 struct inode *check_dirty_dir_inode(struct f2fs_sb_info *sbi, nid_t ino)
550 {
551 	struct list_head *head = &sbi->dir_inode_list;
552 	struct list_head *this;
553 	struct inode *inode = NULL;
554 
555 	spin_lock(&sbi->dir_inode_lock);
556 	list_for_each(this, head) {
557 		struct dir_inode_entry *entry;
558 		entry = list_entry(this, struct dir_inode_entry, list);
559 		if (entry->inode->i_ino == ino) {
560 			inode = entry->inode;
561 			break;
562 		}
563 	}
564 	spin_unlock(&sbi->dir_inode_lock);
565 	return inode;
566 }
567 
568 void sync_dirty_dir_inodes(struct f2fs_sb_info *sbi)
569 {
570 	struct list_head *head = &sbi->dir_inode_list;
571 	struct dir_inode_entry *entry;
572 	struct inode *inode;
573 retry:
574 	spin_lock(&sbi->dir_inode_lock);
575 	if (list_empty(head)) {
576 		spin_unlock(&sbi->dir_inode_lock);
577 		return;
578 	}
579 	entry = list_entry(head->next, struct dir_inode_entry, list);
580 	inode = igrab(entry->inode);
581 	spin_unlock(&sbi->dir_inode_lock);
582 	if (inode) {
583 		filemap_flush(inode->i_mapping);
584 		iput(inode);
585 	} else {
586 		/*
587 		 * We should submit bio, since it exists several
588 		 * wribacking dentry pages in the freeing inode.
589 		 */
590 		f2fs_submit_bio(sbi, DATA, true);
591 	}
592 	goto retry;
593 }
594 
595 /*
596  * Freeze all the FS-operations for checkpoint.
597  */
598 static void block_operations(struct f2fs_sb_info *sbi)
599 {
600 	struct writeback_control wbc = {
601 		.sync_mode = WB_SYNC_ALL,
602 		.nr_to_write = LONG_MAX,
603 		.for_reclaim = 0,
604 	};
605 	struct blk_plug plug;
606 
607 	blk_start_plug(&plug);
608 
609 retry_flush_dents:
610 	f2fs_lock_all(sbi);
611 	/* write all the dirty dentry pages */
612 	if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
613 		f2fs_unlock_all(sbi);
614 		sync_dirty_dir_inodes(sbi);
615 		goto retry_flush_dents;
616 	}
617 
618 	/*
619 	 * POR: we should ensure that there is no dirty node pages
620 	 * until finishing nat/sit flush.
621 	 */
622 retry_flush_nodes:
623 	mutex_lock(&sbi->node_write);
624 
625 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
626 		mutex_unlock(&sbi->node_write);
627 		sync_node_pages(sbi, 0, &wbc);
628 		goto retry_flush_nodes;
629 	}
630 	blk_finish_plug(&plug);
631 }
632 
633 static void unblock_operations(struct f2fs_sb_info *sbi)
634 {
635 	mutex_unlock(&sbi->node_write);
636 	f2fs_unlock_all(sbi);
637 }
638 
639 static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
640 {
641 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
642 	nid_t last_nid = 0;
643 	block_t start_blk;
644 	struct page *cp_page;
645 	unsigned int data_sum_blocks, orphan_blocks;
646 	__u32 crc32 = 0;
647 	void *kaddr;
648 	int i;
649 
650 	/* Flush all the NAT/SIT pages */
651 	while (get_pages(sbi, F2FS_DIRTY_META))
652 		sync_meta_pages(sbi, META, LONG_MAX);
653 
654 	next_free_nid(sbi, &last_nid);
655 
656 	/*
657 	 * modify checkpoint
658 	 * version number is already updated
659 	 */
660 	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi));
661 	ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
662 	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
663 	for (i = 0; i < 3; i++) {
664 		ckpt->cur_node_segno[i] =
665 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
666 		ckpt->cur_node_blkoff[i] =
667 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
668 		ckpt->alloc_type[i + CURSEG_HOT_NODE] =
669 				curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
670 	}
671 	for (i = 0; i < 3; i++) {
672 		ckpt->cur_data_segno[i] =
673 			cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
674 		ckpt->cur_data_blkoff[i] =
675 			cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
676 		ckpt->alloc_type[i + CURSEG_HOT_DATA] =
677 				curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
678 	}
679 
680 	ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
681 	ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
682 	ckpt->next_free_nid = cpu_to_le32(last_nid);
683 
684 	/* 2 cp  + n data seg summary + orphan inode blocks */
685 	data_sum_blocks = npages_for_summary_flush(sbi);
686 	if (data_sum_blocks < 3)
687 		set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
688 	else
689 		clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
690 
691 	orphan_blocks = (sbi->n_orphans + F2FS_ORPHANS_PER_BLOCK - 1)
692 					/ F2FS_ORPHANS_PER_BLOCK;
693 	ckpt->cp_pack_start_sum = cpu_to_le32(1 + orphan_blocks);
694 
695 	if (is_umount) {
696 		set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
697 		ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
698 			data_sum_blocks + orphan_blocks + NR_CURSEG_NODE_TYPE);
699 	} else {
700 		clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
701 		ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
702 			data_sum_blocks + orphan_blocks);
703 	}
704 
705 	if (sbi->n_orphans)
706 		set_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
707 	else
708 		clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
709 
710 	/* update SIT/NAT bitmap */
711 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
712 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
713 
714 	crc32 = f2fs_crc32(ckpt, le32_to_cpu(ckpt->checksum_offset));
715 	*((__le32 *)((unsigned char *)ckpt +
716 				le32_to_cpu(ckpt->checksum_offset)))
717 				= cpu_to_le32(crc32);
718 
719 	start_blk = __start_cp_addr(sbi);
720 
721 	/* write out checkpoint buffer at block 0 */
722 	cp_page = grab_meta_page(sbi, start_blk++);
723 	kaddr = page_address(cp_page);
724 	memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
725 	set_page_dirty(cp_page);
726 	f2fs_put_page(cp_page, 1);
727 
728 	if (sbi->n_orphans) {
729 		write_orphan_inodes(sbi, start_blk);
730 		start_blk += orphan_blocks;
731 	}
732 
733 	write_data_summaries(sbi, start_blk);
734 	start_blk += data_sum_blocks;
735 	if (is_umount) {
736 		write_node_summaries(sbi, start_blk);
737 		start_blk += NR_CURSEG_NODE_TYPE;
738 	}
739 
740 	/* writeout checkpoint block */
741 	cp_page = grab_meta_page(sbi, start_blk);
742 	kaddr = page_address(cp_page);
743 	memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
744 	set_page_dirty(cp_page);
745 	f2fs_put_page(cp_page, 1);
746 
747 	/* wait for previous submitted node/meta pages writeback */
748 	sbi->cp_task = current;
749 	while (get_pages(sbi, F2FS_WRITEBACK)) {
750 		set_current_state(TASK_UNINTERRUPTIBLE);
751 		if (!get_pages(sbi, F2FS_WRITEBACK))
752 			break;
753 		io_schedule();
754 	}
755 	__set_current_state(TASK_RUNNING);
756 	sbi->cp_task = NULL;
757 
758 	filemap_fdatawait_range(sbi->node_inode->i_mapping, 0, LONG_MAX);
759 	filemap_fdatawait_range(sbi->meta_inode->i_mapping, 0, LONG_MAX);
760 
761 	/* update user_block_counts */
762 	sbi->last_valid_block_count = sbi->total_valid_block_count;
763 	sbi->alloc_valid_block_count = 0;
764 
765 	/* Here, we only have one bio having CP pack */
766 	sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
767 
768 	if (!is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
769 		clear_prefree_segments(sbi);
770 		F2FS_RESET_SB_DIRT(sbi);
771 	}
772 }
773 
774 /*
775  * We guarantee that this checkpoint procedure should not fail.
776  */
777 void write_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
778 {
779 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
780 	unsigned long long ckpt_ver;
781 
782 	trace_f2fs_write_checkpoint(sbi->sb, is_umount, "start block_ops");
783 
784 	mutex_lock(&sbi->cp_mutex);
785 	block_operations(sbi);
786 
787 	trace_f2fs_write_checkpoint(sbi->sb, is_umount, "finish block_ops");
788 
789 	f2fs_submit_bio(sbi, DATA, true);
790 	f2fs_submit_bio(sbi, NODE, true);
791 	f2fs_submit_bio(sbi, META, true);
792 
793 	/*
794 	 * update checkpoint pack index
795 	 * Increase the version number so that
796 	 * SIT entries and seg summaries are written at correct place
797 	 */
798 	ckpt_ver = cur_cp_version(ckpt);
799 	ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
800 
801 	/* write cached NAT/SIT entries to NAT/SIT area */
802 	flush_nat_entries(sbi);
803 	flush_sit_entries(sbi);
804 
805 	/* unlock all the fs_lock[] in do_checkpoint() */
806 	do_checkpoint(sbi, is_umount);
807 
808 	unblock_operations(sbi);
809 	mutex_unlock(&sbi->cp_mutex);
810 
811 	trace_f2fs_write_checkpoint(sbi->sb, is_umount, "finish checkpoint");
812 }
813 
814 void init_orphan_info(struct f2fs_sb_info *sbi)
815 {
816 	mutex_init(&sbi->orphan_inode_mutex);
817 	INIT_LIST_HEAD(&sbi->orphan_inode_list);
818 	sbi->n_orphans = 0;
819 }
820 
821 int __init create_checkpoint_caches(void)
822 {
823 	orphan_entry_slab = f2fs_kmem_cache_create("f2fs_orphan_entry",
824 			sizeof(struct orphan_inode_entry), NULL);
825 	if (unlikely(!orphan_entry_slab))
826 		return -ENOMEM;
827 	inode_entry_slab = f2fs_kmem_cache_create("f2fs_dirty_dir_entry",
828 			sizeof(struct dir_inode_entry), NULL);
829 	if (unlikely(!inode_entry_slab)) {
830 		kmem_cache_destroy(orphan_entry_slab);
831 		return -ENOMEM;
832 	}
833 	return 0;
834 }
835 
836 void destroy_checkpoint_caches(void)
837 {
838 	kmem_cache_destroy(orphan_entry_slab);
839 	kmem_cache_destroy(inode_entry_slab);
840 }
841