xref: /linux/fs/f2fs/segment.c (revision fbce3befd60d40639bf3c6b60f7477b2f988f92d)
1 /*
2  * fs/f2fs/segment.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/f2fs_fs.h>
13 #include <linux/bio.h>
14 #include <linux/blkdev.h>
15 #include <linux/prefetch.h>
16 #include <linux/kthread.h>
17 #include <linux/swap.h>
18 #include <linux/timer.h>
19 
20 #include "f2fs.h"
21 #include "segment.h"
22 #include "node.h"
23 #include "trace.h"
24 #include <trace/events/f2fs.h>
25 
26 #define __reverse_ffz(x) __reverse_ffs(~(x))
27 
28 static struct kmem_cache *discard_entry_slab;
29 static struct kmem_cache *sit_entry_set_slab;
30 static struct kmem_cache *inmem_entry_slab;
31 
32 static unsigned long __reverse_ulong(unsigned char *str)
33 {
34 	unsigned long tmp = 0;
35 	int shift = 24, idx = 0;
36 
37 #if BITS_PER_LONG == 64
38 	shift = 56;
39 #endif
40 	while (shift >= 0) {
41 		tmp |= (unsigned long)str[idx++] << shift;
42 		shift -= BITS_PER_BYTE;
43 	}
44 	return tmp;
45 }
46 
47 /*
48  * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
49  * MSB and LSB are reversed in a byte by f2fs_set_bit.
50  */
51 static inline unsigned long __reverse_ffs(unsigned long word)
52 {
53 	int num = 0;
54 
55 #if BITS_PER_LONG == 64
56 	if ((word & 0xffffffff00000000UL) == 0)
57 		num += 32;
58 	else
59 		word >>= 32;
60 #endif
61 	if ((word & 0xffff0000) == 0)
62 		num += 16;
63 	else
64 		word >>= 16;
65 
66 	if ((word & 0xff00) == 0)
67 		num += 8;
68 	else
69 		word >>= 8;
70 
71 	if ((word & 0xf0) == 0)
72 		num += 4;
73 	else
74 		word >>= 4;
75 
76 	if ((word & 0xc) == 0)
77 		num += 2;
78 	else
79 		word >>= 2;
80 
81 	if ((word & 0x2) == 0)
82 		num += 1;
83 	return num;
84 }
85 
86 /*
87  * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because
88  * f2fs_set_bit makes MSB and LSB reversed in a byte.
89  * @size must be integral times of unsigned long.
90  * Example:
91  *                             MSB <--> LSB
92  *   f2fs_set_bit(0, bitmap) => 1000 0000
93  *   f2fs_set_bit(7, bitmap) => 0000 0001
94  */
95 static unsigned long __find_rev_next_bit(const unsigned long *addr,
96 			unsigned long size, unsigned long offset)
97 {
98 	const unsigned long *p = addr + BIT_WORD(offset);
99 	unsigned long result = size;
100 	unsigned long tmp;
101 
102 	if (offset >= size)
103 		return size;
104 
105 	size -= (offset & ~(BITS_PER_LONG - 1));
106 	offset %= BITS_PER_LONG;
107 
108 	while (1) {
109 		if (*p == 0)
110 			goto pass;
111 
112 		tmp = __reverse_ulong((unsigned char *)p);
113 
114 		tmp &= ~0UL >> offset;
115 		if (size < BITS_PER_LONG)
116 			tmp &= (~0UL << (BITS_PER_LONG - size));
117 		if (tmp)
118 			goto found;
119 pass:
120 		if (size <= BITS_PER_LONG)
121 			break;
122 		size -= BITS_PER_LONG;
123 		offset = 0;
124 		p++;
125 	}
126 	return result;
127 found:
128 	return result - size + __reverse_ffs(tmp);
129 }
130 
131 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
132 			unsigned long size, unsigned long offset)
133 {
134 	const unsigned long *p = addr + BIT_WORD(offset);
135 	unsigned long result = size;
136 	unsigned long tmp;
137 
138 	if (offset >= size)
139 		return size;
140 
141 	size -= (offset & ~(BITS_PER_LONG - 1));
142 	offset %= BITS_PER_LONG;
143 
144 	while (1) {
145 		if (*p == ~0UL)
146 			goto pass;
147 
148 		tmp = __reverse_ulong((unsigned char *)p);
149 
150 		if (offset)
151 			tmp |= ~0UL << (BITS_PER_LONG - offset);
152 		if (size < BITS_PER_LONG)
153 			tmp |= ~0UL >> size;
154 		if (tmp != ~0UL)
155 			goto found;
156 pass:
157 		if (size <= BITS_PER_LONG)
158 			break;
159 		size -= BITS_PER_LONG;
160 		offset = 0;
161 		p++;
162 	}
163 	return result;
164 found:
165 	return result - size + __reverse_ffz(tmp);
166 }
167 
168 void register_inmem_page(struct inode *inode, struct page *page)
169 {
170 	struct f2fs_inode_info *fi = F2FS_I(inode);
171 	struct inmem_pages *new;
172 
173 	f2fs_trace_pid(page);
174 
175 	set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE);
176 	SetPagePrivate(page);
177 
178 	new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
179 
180 	/* add atomic page indices to the list */
181 	new->page = page;
182 	INIT_LIST_HEAD(&new->list);
183 
184 	/* increase reference count with clean state */
185 	mutex_lock(&fi->inmem_lock);
186 	get_page(page);
187 	list_add_tail(&new->list, &fi->inmem_pages);
188 	inc_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
189 	mutex_unlock(&fi->inmem_lock);
190 
191 	trace_f2fs_register_inmem_page(page, INMEM);
192 }
193 
194 static int __revoke_inmem_pages(struct inode *inode,
195 				struct list_head *head, bool drop, bool recover)
196 {
197 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
198 	struct inmem_pages *cur, *tmp;
199 	int err = 0;
200 
201 	list_for_each_entry_safe(cur, tmp, head, list) {
202 		struct page *page = cur->page;
203 
204 		if (drop)
205 			trace_f2fs_commit_inmem_page(page, INMEM_DROP);
206 
207 		lock_page(page);
208 
209 		if (recover) {
210 			struct dnode_of_data dn;
211 			struct node_info ni;
212 
213 			trace_f2fs_commit_inmem_page(page, INMEM_REVOKE);
214 
215 			set_new_dnode(&dn, inode, NULL, NULL, 0);
216 			if (get_dnode_of_data(&dn, page->index, LOOKUP_NODE)) {
217 				err = -EAGAIN;
218 				goto next;
219 			}
220 			get_node_info(sbi, dn.nid, &ni);
221 			f2fs_replace_block(sbi, &dn, dn.data_blkaddr,
222 					cur->old_addr, ni.version, true, true);
223 			f2fs_put_dnode(&dn);
224 		}
225 next:
226 		ClearPageUptodate(page);
227 		set_page_private(page, 0);
228 		ClearPageUptodate(page);
229 		f2fs_put_page(page, 1);
230 
231 		list_del(&cur->list);
232 		kmem_cache_free(inmem_entry_slab, cur);
233 		dec_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
234 	}
235 	return err;
236 }
237 
238 void drop_inmem_pages(struct inode *inode)
239 {
240 	struct f2fs_inode_info *fi = F2FS_I(inode);
241 
242 	mutex_lock(&fi->inmem_lock);
243 	__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
244 	mutex_unlock(&fi->inmem_lock);
245 }
246 
247 static int __commit_inmem_pages(struct inode *inode,
248 					struct list_head *revoke_list)
249 {
250 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
251 	struct f2fs_inode_info *fi = F2FS_I(inode);
252 	struct inmem_pages *cur, *tmp;
253 	struct f2fs_io_info fio = {
254 		.sbi = sbi,
255 		.type = DATA,
256 		.rw = WRITE_SYNC | REQ_PRIO,
257 		.encrypted_page = NULL,
258 	};
259 	bool submit_bio = false;
260 	int err = 0;
261 
262 	list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
263 		struct page *page = cur->page;
264 
265 		lock_page(page);
266 		if (page->mapping == inode->i_mapping) {
267 			trace_f2fs_commit_inmem_page(page, INMEM);
268 
269 			set_page_dirty(page);
270 			f2fs_wait_on_page_writeback(page, DATA, true);
271 			if (clear_page_dirty_for_io(page))
272 				inode_dec_dirty_pages(inode);
273 
274 			fio.page = page;
275 			err = do_write_data_page(&fio);
276 			if (err) {
277 				unlock_page(page);
278 				break;
279 			}
280 
281 			/* record old blkaddr for revoking */
282 			cur->old_addr = fio.old_blkaddr;
283 
284 			clear_cold_data(page);
285 			submit_bio = true;
286 		}
287 		unlock_page(page);
288 		list_move_tail(&cur->list, revoke_list);
289 	}
290 
291 	if (submit_bio)
292 		f2fs_submit_merged_bio_cond(sbi, inode, NULL, 0, DATA, WRITE);
293 
294 	if (!err)
295 		__revoke_inmem_pages(inode, revoke_list, false, false);
296 
297 	return err;
298 }
299 
300 int commit_inmem_pages(struct inode *inode)
301 {
302 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
303 	struct f2fs_inode_info *fi = F2FS_I(inode);
304 	struct list_head revoke_list;
305 	int err;
306 
307 	INIT_LIST_HEAD(&revoke_list);
308 	f2fs_balance_fs(sbi, true);
309 	f2fs_lock_op(sbi);
310 
311 	mutex_lock(&fi->inmem_lock);
312 	err = __commit_inmem_pages(inode, &revoke_list);
313 	if (err) {
314 		int ret;
315 		/*
316 		 * try to revoke all committed pages, but still we could fail
317 		 * due to no memory or other reason, if that happened, EAGAIN
318 		 * will be returned, which means in such case, transaction is
319 		 * already not integrity, caller should use journal to do the
320 		 * recovery or rewrite & commit last transaction. For other
321 		 * error number, revoking was done by filesystem itself.
322 		 */
323 		ret = __revoke_inmem_pages(inode, &revoke_list, false, true);
324 		if (ret)
325 			err = ret;
326 
327 		/* drop all uncommitted pages */
328 		__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
329 	}
330 	mutex_unlock(&fi->inmem_lock);
331 
332 	f2fs_unlock_op(sbi);
333 	return err;
334 }
335 
336 /*
337  * This function balances dirty node and dentry pages.
338  * In addition, it controls garbage collection.
339  */
340 void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
341 {
342 	if (!need)
343 		return;
344 	/*
345 	 * We should do GC or end up with checkpoint, if there are so many dirty
346 	 * dir/node pages without enough free segments.
347 	 */
348 	if (has_not_enough_free_secs(sbi, 0)) {
349 		mutex_lock(&sbi->gc_mutex);
350 		f2fs_gc(sbi, false);
351 	}
352 }
353 
354 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
355 {
356 	/* try to shrink extent cache when there is no enough memory */
357 	if (!available_free_memory(sbi, EXTENT_CACHE))
358 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
359 
360 	/* check the # of cached NAT entries */
361 	if (!available_free_memory(sbi, NAT_ENTRIES))
362 		try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
363 
364 	if (!available_free_memory(sbi, FREE_NIDS))
365 		try_to_free_nids(sbi, NAT_ENTRY_PER_BLOCK * FREE_NID_PAGES);
366 
367 	/* checkpoint is the only way to shrink partial cached entries */
368 	if (!available_free_memory(sbi, NAT_ENTRIES) ||
369 			!available_free_memory(sbi, INO_ENTRIES) ||
370 			excess_prefree_segs(sbi) ||
371 			excess_dirty_nats(sbi) ||
372 			(is_idle(sbi) && f2fs_time_over(sbi, CP_TIME))) {
373 		if (test_opt(sbi, DATA_FLUSH)) {
374 			struct blk_plug plug;
375 
376 			blk_start_plug(&plug);
377 			sync_dirty_inodes(sbi, FILE_INODE);
378 			blk_finish_plug(&plug);
379 		}
380 		f2fs_sync_fs(sbi->sb, true);
381 		stat_inc_bg_cp_count(sbi->stat_info);
382 	}
383 }
384 
385 static int issue_flush_thread(void *data)
386 {
387 	struct f2fs_sb_info *sbi = data;
388 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
389 	wait_queue_head_t *q = &fcc->flush_wait_queue;
390 repeat:
391 	if (kthread_should_stop())
392 		return 0;
393 
394 	if (!llist_empty(&fcc->issue_list)) {
395 		struct bio *bio;
396 		struct flush_cmd *cmd, *next;
397 		int ret;
398 
399 		bio = f2fs_bio_alloc(0);
400 
401 		fcc->dispatch_list = llist_del_all(&fcc->issue_list);
402 		fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
403 
404 		bio->bi_bdev = sbi->sb->s_bdev;
405 		ret = submit_bio_wait(WRITE_FLUSH, bio);
406 
407 		llist_for_each_entry_safe(cmd, next,
408 					  fcc->dispatch_list, llnode) {
409 			cmd->ret = ret;
410 			complete(&cmd->wait);
411 		}
412 		bio_put(bio);
413 		fcc->dispatch_list = NULL;
414 	}
415 
416 	wait_event_interruptible(*q,
417 		kthread_should_stop() || !llist_empty(&fcc->issue_list));
418 	goto repeat;
419 }
420 
421 int f2fs_issue_flush(struct f2fs_sb_info *sbi)
422 {
423 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
424 	struct flush_cmd cmd;
425 
426 	trace_f2fs_issue_flush(sbi->sb, test_opt(sbi, NOBARRIER),
427 					test_opt(sbi, FLUSH_MERGE));
428 
429 	if (test_opt(sbi, NOBARRIER))
430 		return 0;
431 
432 	if (!test_opt(sbi, FLUSH_MERGE)) {
433 		struct bio *bio = f2fs_bio_alloc(0);
434 		int ret;
435 
436 		bio->bi_bdev = sbi->sb->s_bdev;
437 		ret = submit_bio_wait(WRITE_FLUSH, bio);
438 		bio_put(bio);
439 		return ret;
440 	}
441 
442 	init_completion(&cmd.wait);
443 
444 	llist_add(&cmd.llnode, &fcc->issue_list);
445 
446 	if (!fcc->dispatch_list)
447 		wake_up(&fcc->flush_wait_queue);
448 
449 	wait_for_completion(&cmd.wait);
450 
451 	return cmd.ret;
452 }
453 
454 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
455 {
456 	dev_t dev = sbi->sb->s_bdev->bd_dev;
457 	struct flush_cmd_control *fcc;
458 	int err = 0;
459 
460 	fcc = kzalloc(sizeof(struct flush_cmd_control), GFP_KERNEL);
461 	if (!fcc)
462 		return -ENOMEM;
463 	init_waitqueue_head(&fcc->flush_wait_queue);
464 	init_llist_head(&fcc->issue_list);
465 	SM_I(sbi)->cmd_control_info = fcc;
466 	fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
467 				"f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
468 	if (IS_ERR(fcc->f2fs_issue_flush)) {
469 		err = PTR_ERR(fcc->f2fs_issue_flush);
470 		kfree(fcc);
471 		SM_I(sbi)->cmd_control_info = NULL;
472 		return err;
473 	}
474 
475 	return err;
476 }
477 
478 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi)
479 {
480 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
481 
482 	if (fcc && fcc->f2fs_issue_flush)
483 		kthread_stop(fcc->f2fs_issue_flush);
484 	kfree(fcc);
485 	SM_I(sbi)->cmd_control_info = NULL;
486 }
487 
488 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
489 		enum dirty_type dirty_type)
490 {
491 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
492 
493 	/* need not be added */
494 	if (IS_CURSEG(sbi, segno))
495 		return;
496 
497 	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
498 		dirty_i->nr_dirty[dirty_type]++;
499 
500 	if (dirty_type == DIRTY) {
501 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
502 		enum dirty_type t = sentry->type;
503 
504 		if (unlikely(t >= DIRTY)) {
505 			f2fs_bug_on(sbi, 1);
506 			return;
507 		}
508 		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
509 			dirty_i->nr_dirty[t]++;
510 	}
511 }
512 
513 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
514 		enum dirty_type dirty_type)
515 {
516 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
517 
518 	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
519 		dirty_i->nr_dirty[dirty_type]--;
520 
521 	if (dirty_type == DIRTY) {
522 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
523 		enum dirty_type t = sentry->type;
524 
525 		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
526 			dirty_i->nr_dirty[t]--;
527 
528 		if (get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0)
529 			clear_bit(GET_SECNO(sbi, segno),
530 						dirty_i->victim_secmap);
531 	}
532 }
533 
534 /*
535  * Should not occur error such as -ENOMEM.
536  * Adding dirty entry into seglist is not critical operation.
537  * If a given segment is one of current working segments, it won't be added.
538  */
539 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
540 {
541 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
542 	unsigned short valid_blocks;
543 
544 	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
545 		return;
546 
547 	mutex_lock(&dirty_i->seglist_lock);
548 
549 	valid_blocks = get_valid_blocks(sbi, segno, 0);
550 
551 	if (valid_blocks == 0) {
552 		__locate_dirty_segment(sbi, segno, PRE);
553 		__remove_dirty_segment(sbi, segno, DIRTY);
554 	} else if (valid_blocks < sbi->blocks_per_seg) {
555 		__locate_dirty_segment(sbi, segno, DIRTY);
556 	} else {
557 		/* Recovery routine with SSR needs this */
558 		__remove_dirty_segment(sbi, segno, DIRTY);
559 	}
560 
561 	mutex_unlock(&dirty_i->seglist_lock);
562 }
563 
564 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
565 				block_t blkstart, block_t blklen)
566 {
567 	sector_t start = SECTOR_FROM_BLOCK(blkstart);
568 	sector_t len = SECTOR_FROM_BLOCK(blklen);
569 	struct seg_entry *se;
570 	unsigned int offset;
571 	block_t i;
572 
573 	for (i = blkstart; i < blkstart + blklen; i++) {
574 		se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
575 		offset = GET_BLKOFF_FROM_SEG0(sbi, i);
576 
577 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
578 			sbi->discard_blks--;
579 	}
580 	trace_f2fs_issue_discard(sbi->sb, blkstart, blklen);
581 	return blkdev_issue_discard(sbi->sb->s_bdev, start, len, GFP_NOFS, 0);
582 }
583 
584 bool discard_next_dnode(struct f2fs_sb_info *sbi, block_t blkaddr)
585 {
586 	int err = -EOPNOTSUPP;
587 
588 	if (test_opt(sbi, DISCARD)) {
589 		struct seg_entry *se = get_seg_entry(sbi,
590 				GET_SEGNO(sbi, blkaddr));
591 		unsigned int offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
592 
593 		if (f2fs_test_bit(offset, se->discard_map))
594 			return false;
595 
596 		err = f2fs_issue_discard(sbi, blkaddr, 1);
597 	}
598 
599 	if (err) {
600 		update_meta_page(sbi, NULL, blkaddr);
601 		return true;
602 	}
603 	return false;
604 }
605 
606 static void __add_discard_entry(struct f2fs_sb_info *sbi,
607 		struct cp_control *cpc, struct seg_entry *se,
608 		unsigned int start, unsigned int end)
609 {
610 	struct list_head *head = &SM_I(sbi)->discard_list;
611 	struct discard_entry *new, *last;
612 
613 	if (!list_empty(head)) {
614 		last = list_last_entry(head, struct discard_entry, list);
615 		if (START_BLOCK(sbi, cpc->trim_start) + start ==
616 						last->blkaddr + last->len) {
617 			last->len += end - start;
618 			goto done;
619 		}
620 	}
621 
622 	new = f2fs_kmem_cache_alloc(discard_entry_slab, GFP_NOFS);
623 	INIT_LIST_HEAD(&new->list);
624 	new->blkaddr = START_BLOCK(sbi, cpc->trim_start) + start;
625 	new->len = end - start;
626 	list_add_tail(&new->list, head);
627 done:
628 	SM_I(sbi)->nr_discards += end - start;
629 }
630 
631 static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
632 {
633 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
634 	int max_blocks = sbi->blocks_per_seg;
635 	struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
636 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
637 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
638 	unsigned long *discard_map = (unsigned long *)se->discard_map;
639 	unsigned long *dmap = SIT_I(sbi)->tmp_map;
640 	unsigned int start = 0, end = -1;
641 	bool force = (cpc->reason == CP_DISCARD);
642 	int i;
643 
644 	if (se->valid_blocks == max_blocks)
645 		return;
646 
647 	if (!force) {
648 		if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
649 		    SM_I(sbi)->nr_discards >= SM_I(sbi)->max_discards)
650 			return;
651 	}
652 
653 	/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
654 	for (i = 0; i < entries; i++)
655 		dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
656 				(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
657 
658 	while (force || SM_I(sbi)->nr_discards <= SM_I(sbi)->max_discards) {
659 		start = __find_rev_next_bit(dmap, max_blocks, end + 1);
660 		if (start >= max_blocks)
661 			break;
662 
663 		end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
664 		__add_discard_entry(sbi, cpc, se, start, end);
665 	}
666 }
667 
668 void release_discard_addrs(struct f2fs_sb_info *sbi)
669 {
670 	struct list_head *head = &(SM_I(sbi)->discard_list);
671 	struct discard_entry *entry, *this;
672 
673 	/* drop caches */
674 	list_for_each_entry_safe(entry, this, head, list) {
675 		list_del(&entry->list);
676 		kmem_cache_free(discard_entry_slab, entry);
677 	}
678 }
679 
680 /*
681  * Should call clear_prefree_segments after checkpoint is done.
682  */
683 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
684 {
685 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
686 	unsigned int segno;
687 
688 	mutex_lock(&dirty_i->seglist_lock);
689 	for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
690 		__set_test_and_free(sbi, segno);
691 	mutex_unlock(&dirty_i->seglist_lock);
692 }
693 
694 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
695 {
696 	struct list_head *head = &(SM_I(sbi)->discard_list);
697 	struct discard_entry *entry, *this;
698 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
699 	unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
700 	unsigned int start = 0, end = -1;
701 
702 	mutex_lock(&dirty_i->seglist_lock);
703 
704 	while (1) {
705 		int i;
706 		start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
707 		if (start >= MAIN_SEGS(sbi))
708 			break;
709 		end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
710 								start + 1);
711 
712 		for (i = start; i < end; i++)
713 			clear_bit(i, prefree_map);
714 
715 		dirty_i->nr_dirty[PRE] -= end - start;
716 
717 		if (!test_opt(sbi, DISCARD))
718 			continue;
719 
720 		f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
721 				(end - start) << sbi->log_blocks_per_seg);
722 	}
723 	mutex_unlock(&dirty_i->seglist_lock);
724 
725 	/* send small discards */
726 	list_for_each_entry_safe(entry, this, head, list) {
727 		if (cpc->reason == CP_DISCARD && entry->len < cpc->trim_minlen)
728 			goto skip;
729 		f2fs_issue_discard(sbi, entry->blkaddr, entry->len);
730 		cpc->trimmed += entry->len;
731 skip:
732 		list_del(&entry->list);
733 		SM_I(sbi)->nr_discards -= entry->len;
734 		kmem_cache_free(discard_entry_slab, entry);
735 	}
736 }
737 
738 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
739 {
740 	struct sit_info *sit_i = SIT_I(sbi);
741 
742 	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
743 		sit_i->dirty_sentries++;
744 		return false;
745 	}
746 
747 	return true;
748 }
749 
750 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
751 					unsigned int segno, int modified)
752 {
753 	struct seg_entry *se = get_seg_entry(sbi, segno);
754 	se->type = type;
755 	if (modified)
756 		__mark_sit_entry_dirty(sbi, segno);
757 }
758 
759 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
760 {
761 	struct seg_entry *se;
762 	unsigned int segno, offset;
763 	long int new_vblocks;
764 
765 	segno = GET_SEGNO(sbi, blkaddr);
766 
767 	se = get_seg_entry(sbi, segno);
768 	new_vblocks = se->valid_blocks + del;
769 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
770 
771 	f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
772 				(new_vblocks > sbi->blocks_per_seg)));
773 
774 	se->valid_blocks = new_vblocks;
775 	se->mtime = get_mtime(sbi);
776 	SIT_I(sbi)->max_mtime = se->mtime;
777 
778 	/* Update valid block bitmap */
779 	if (del > 0) {
780 		if (f2fs_test_and_set_bit(offset, se->cur_valid_map))
781 			f2fs_bug_on(sbi, 1);
782 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
783 			sbi->discard_blks--;
784 	} else {
785 		if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map))
786 			f2fs_bug_on(sbi, 1);
787 		if (f2fs_test_and_clear_bit(offset, se->discard_map))
788 			sbi->discard_blks++;
789 	}
790 	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
791 		se->ckpt_valid_blocks += del;
792 
793 	__mark_sit_entry_dirty(sbi, segno);
794 
795 	/* update total number of valid blocks to be written in ckpt area */
796 	SIT_I(sbi)->written_valid_blocks += del;
797 
798 	if (sbi->segs_per_sec > 1)
799 		get_sec_entry(sbi, segno)->valid_blocks += del;
800 }
801 
802 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new)
803 {
804 	update_sit_entry(sbi, new, 1);
805 	if (GET_SEGNO(sbi, old) != NULL_SEGNO)
806 		update_sit_entry(sbi, old, -1);
807 
808 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old));
809 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new));
810 }
811 
812 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
813 {
814 	unsigned int segno = GET_SEGNO(sbi, addr);
815 	struct sit_info *sit_i = SIT_I(sbi);
816 
817 	f2fs_bug_on(sbi, addr == NULL_ADDR);
818 	if (addr == NEW_ADDR)
819 		return;
820 
821 	/* add it into sit main buffer */
822 	mutex_lock(&sit_i->sentry_lock);
823 
824 	update_sit_entry(sbi, addr, -1);
825 
826 	/* add it into dirty seglist */
827 	locate_dirty_segment(sbi, segno);
828 
829 	mutex_unlock(&sit_i->sentry_lock);
830 }
831 
832 bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
833 {
834 	struct sit_info *sit_i = SIT_I(sbi);
835 	unsigned int segno, offset;
836 	struct seg_entry *se;
837 	bool is_cp = false;
838 
839 	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR)
840 		return true;
841 
842 	mutex_lock(&sit_i->sentry_lock);
843 
844 	segno = GET_SEGNO(sbi, blkaddr);
845 	se = get_seg_entry(sbi, segno);
846 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
847 
848 	if (f2fs_test_bit(offset, se->ckpt_valid_map))
849 		is_cp = true;
850 
851 	mutex_unlock(&sit_i->sentry_lock);
852 
853 	return is_cp;
854 }
855 
856 /*
857  * This function should be resided under the curseg_mutex lock
858  */
859 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
860 					struct f2fs_summary *sum)
861 {
862 	struct curseg_info *curseg = CURSEG_I(sbi, type);
863 	void *addr = curseg->sum_blk;
864 	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
865 	memcpy(addr, sum, sizeof(struct f2fs_summary));
866 }
867 
868 /*
869  * Calculate the number of current summary pages for writing
870  */
871 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
872 {
873 	int valid_sum_count = 0;
874 	int i, sum_in_page;
875 
876 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
877 		if (sbi->ckpt->alloc_type[i] == SSR)
878 			valid_sum_count += sbi->blocks_per_seg;
879 		else {
880 			if (for_ra)
881 				valid_sum_count += le16_to_cpu(
882 					F2FS_CKPT(sbi)->cur_data_blkoff[i]);
883 			else
884 				valid_sum_count += curseg_blkoff(sbi, i);
885 		}
886 	}
887 
888 	sum_in_page = (PAGE_SIZE - 2 * SUM_JOURNAL_SIZE -
889 			SUM_FOOTER_SIZE) / SUMMARY_SIZE;
890 	if (valid_sum_count <= sum_in_page)
891 		return 1;
892 	else if ((valid_sum_count - sum_in_page) <=
893 		(PAGE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
894 		return 2;
895 	return 3;
896 }
897 
898 /*
899  * Caller should put this summary page
900  */
901 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
902 {
903 	return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
904 }
905 
906 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr)
907 {
908 	struct page *page = grab_meta_page(sbi, blk_addr);
909 	void *dst = page_address(page);
910 
911 	if (src)
912 		memcpy(dst, src, PAGE_SIZE);
913 	else
914 		memset(dst, 0, PAGE_SIZE);
915 	set_page_dirty(page);
916 	f2fs_put_page(page, 1);
917 }
918 
919 static void write_sum_page(struct f2fs_sb_info *sbi,
920 			struct f2fs_summary_block *sum_blk, block_t blk_addr)
921 {
922 	update_meta_page(sbi, (void *)sum_blk, blk_addr);
923 }
924 
925 static void write_current_sum_page(struct f2fs_sb_info *sbi,
926 						int type, block_t blk_addr)
927 {
928 	struct curseg_info *curseg = CURSEG_I(sbi, type);
929 	struct page *page = grab_meta_page(sbi, blk_addr);
930 	struct f2fs_summary_block *src = curseg->sum_blk;
931 	struct f2fs_summary_block *dst;
932 
933 	dst = (struct f2fs_summary_block *)page_address(page);
934 
935 	mutex_lock(&curseg->curseg_mutex);
936 
937 	down_read(&curseg->journal_rwsem);
938 	memcpy(&dst->journal, curseg->journal, SUM_JOURNAL_SIZE);
939 	up_read(&curseg->journal_rwsem);
940 
941 	memcpy(dst->entries, src->entries, SUM_ENTRY_SIZE);
942 	memcpy(&dst->footer, &src->footer, SUM_FOOTER_SIZE);
943 
944 	mutex_unlock(&curseg->curseg_mutex);
945 
946 	set_page_dirty(page);
947 	f2fs_put_page(page, 1);
948 }
949 
950 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
951 {
952 	struct curseg_info *curseg = CURSEG_I(sbi, type);
953 	unsigned int segno = curseg->segno + 1;
954 	struct free_segmap_info *free_i = FREE_I(sbi);
955 
956 	if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
957 		return !test_bit(segno, free_i->free_segmap);
958 	return 0;
959 }
960 
961 /*
962  * Find a new segment from the free segments bitmap to right order
963  * This function should be returned with success, otherwise BUG
964  */
965 static void get_new_segment(struct f2fs_sb_info *sbi,
966 			unsigned int *newseg, bool new_sec, int dir)
967 {
968 	struct free_segmap_info *free_i = FREE_I(sbi);
969 	unsigned int segno, secno, zoneno;
970 	unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
971 	unsigned int hint = *newseg / sbi->segs_per_sec;
972 	unsigned int old_zoneno = GET_ZONENO_FROM_SEGNO(sbi, *newseg);
973 	unsigned int left_start = hint;
974 	bool init = true;
975 	int go_left = 0;
976 	int i;
977 
978 	spin_lock(&free_i->segmap_lock);
979 
980 	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
981 		segno = find_next_zero_bit(free_i->free_segmap,
982 				(hint + 1) * sbi->segs_per_sec, *newseg + 1);
983 		if (segno < (hint + 1) * sbi->segs_per_sec)
984 			goto got_it;
985 	}
986 find_other_zone:
987 	secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
988 	if (secno >= MAIN_SECS(sbi)) {
989 		if (dir == ALLOC_RIGHT) {
990 			secno = find_next_zero_bit(free_i->free_secmap,
991 							MAIN_SECS(sbi), 0);
992 			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
993 		} else {
994 			go_left = 1;
995 			left_start = hint - 1;
996 		}
997 	}
998 	if (go_left == 0)
999 		goto skip_left;
1000 
1001 	while (test_bit(left_start, free_i->free_secmap)) {
1002 		if (left_start > 0) {
1003 			left_start--;
1004 			continue;
1005 		}
1006 		left_start = find_next_zero_bit(free_i->free_secmap,
1007 							MAIN_SECS(sbi), 0);
1008 		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
1009 		break;
1010 	}
1011 	secno = left_start;
1012 skip_left:
1013 	hint = secno;
1014 	segno = secno * sbi->segs_per_sec;
1015 	zoneno = secno / sbi->secs_per_zone;
1016 
1017 	/* give up on finding another zone */
1018 	if (!init)
1019 		goto got_it;
1020 	if (sbi->secs_per_zone == 1)
1021 		goto got_it;
1022 	if (zoneno == old_zoneno)
1023 		goto got_it;
1024 	if (dir == ALLOC_LEFT) {
1025 		if (!go_left && zoneno + 1 >= total_zones)
1026 			goto got_it;
1027 		if (go_left && zoneno == 0)
1028 			goto got_it;
1029 	}
1030 	for (i = 0; i < NR_CURSEG_TYPE; i++)
1031 		if (CURSEG_I(sbi, i)->zone == zoneno)
1032 			break;
1033 
1034 	if (i < NR_CURSEG_TYPE) {
1035 		/* zone is in user, try another */
1036 		if (go_left)
1037 			hint = zoneno * sbi->secs_per_zone - 1;
1038 		else if (zoneno + 1 >= total_zones)
1039 			hint = 0;
1040 		else
1041 			hint = (zoneno + 1) * sbi->secs_per_zone;
1042 		init = false;
1043 		goto find_other_zone;
1044 	}
1045 got_it:
1046 	/* set it as dirty segment in free segmap */
1047 	f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
1048 	__set_inuse(sbi, segno);
1049 	*newseg = segno;
1050 	spin_unlock(&free_i->segmap_lock);
1051 }
1052 
1053 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
1054 {
1055 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1056 	struct summary_footer *sum_footer;
1057 
1058 	curseg->segno = curseg->next_segno;
1059 	curseg->zone = GET_ZONENO_FROM_SEGNO(sbi, curseg->segno);
1060 	curseg->next_blkoff = 0;
1061 	curseg->next_segno = NULL_SEGNO;
1062 
1063 	sum_footer = &(curseg->sum_blk->footer);
1064 	memset(sum_footer, 0, sizeof(struct summary_footer));
1065 	if (IS_DATASEG(type))
1066 		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
1067 	if (IS_NODESEG(type))
1068 		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
1069 	__set_sit_entry_type(sbi, type, curseg->segno, modified);
1070 }
1071 
1072 /*
1073  * Allocate a current working segment.
1074  * This function always allocates a free segment in LFS manner.
1075  */
1076 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
1077 {
1078 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1079 	unsigned int segno = curseg->segno;
1080 	int dir = ALLOC_LEFT;
1081 
1082 	write_sum_page(sbi, curseg->sum_blk,
1083 				GET_SUM_BLOCK(sbi, segno));
1084 	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
1085 		dir = ALLOC_RIGHT;
1086 
1087 	if (test_opt(sbi, NOHEAP))
1088 		dir = ALLOC_RIGHT;
1089 
1090 	get_new_segment(sbi, &segno, new_sec, dir);
1091 	curseg->next_segno = segno;
1092 	reset_curseg(sbi, type, 1);
1093 	curseg->alloc_type = LFS;
1094 }
1095 
1096 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
1097 			struct curseg_info *seg, block_t start)
1098 {
1099 	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
1100 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1101 	unsigned long *target_map = SIT_I(sbi)->tmp_map;
1102 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1103 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1104 	int i, pos;
1105 
1106 	for (i = 0; i < entries; i++)
1107 		target_map[i] = ckpt_map[i] | cur_map[i];
1108 
1109 	pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
1110 
1111 	seg->next_blkoff = pos;
1112 }
1113 
1114 /*
1115  * If a segment is written by LFS manner, next block offset is just obtained
1116  * by increasing the current block offset. However, if a segment is written by
1117  * SSR manner, next block offset obtained by calling __next_free_blkoff
1118  */
1119 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
1120 				struct curseg_info *seg)
1121 {
1122 	if (seg->alloc_type == SSR)
1123 		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
1124 	else
1125 		seg->next_blkoff++;
1126 }
1127 
1128 /*
1129  * This function always allocates a used segment(from dirty seglist) by SSR
1130  * manner, so it should recover the existing segment information of valid blocks
1131  */
1132 static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
1133 {
1134 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1135 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1136 	unsigned int new_segno = curseg->next_segno;
1137 	struct f2fs_summary_block *sum_node;
1138 	struct page *sum_page;
1139 
1140 	write_sum_page(sbi, curseg->sum_blk,
1141 				GET_SUM_BLOCK(sbi, curseg->segno));
1142 	__set_test_and_inuse(sbi, new_segno);
1143 
1144 	mutex_lock(&dirty_i->seglist_lock);
1145 	__remove_dirty_segment(sbi, new_segno, PRE);
1146 	__remove_dirty_segment(sbi, new_segno, DIRTY);
1147 	mutex_unlock(&dirty_i->seglist_lock);
1148 
1149 	reset_curseg(sbi, type, 1);
1150 	curseg->alloc_type = SSR;
1151 	__next_free_blkoff(sbi, curseg, 0);
1152 
1153 	if (reuse) {
1154 		sum_page = get_sum_page(sbi, new_segno);
1155 		sum_node = (struct f2fs_summary_block *)page_address(sum_page);
1156 		memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
1157 		f2fs_put_page(sum_page, 1);
1158 	}
1159 }
1160 
1161 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
1162 {
1163 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1164 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
1165 
1166 	if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0))
1167 		return v_ops->get_victim(sbi,
1168 				&(curseg)->next_segno, BG_GC, type, SSR);
1169 
1170 	/* For data segments, let's do SSR more intensively */
1171 	for (; type >= CURSEG_HOT_DATA; type--)
1172 		if (v_ops->get_victim(sbi, &(curseg)->next_segno,
1173 						BG_GC, type, SSR))
1174 			return 1;
1175 	return 0;
1176 }
1177 
1178 /*
1179  * flush out current segment and replace it with new segment
1180  * This function should be returned with success, otherwise BUG
1181  */
1182 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
1183 						int type, bool force)
1184 {
1185 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1186 
1187 	if (force)
1188 		new_curseg(sbi, type, true);
1189 	else if (type == CURSEG_WARM_NODE)
1190 		new_curseg(sbi, type, false);
1191 	else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
1192 		new_curseg(sbi, type, false);
1193 	else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
1194 		change_curseg(sbi, type, true);
1195 	else
1196 		new_curseg(sbi, type, false);
1197 
1198 	stat_inc_seg_type(sbi, curseg);
1199 }
1200 
1201 static void __allocate_new_segments(struct f2fs_sb_info *sbi, int type)
1202 {
1203 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1204 	unsigned int old_segno;
1205 
1206 	old_segno = curseg->segno;
1207 	SIT_I(sbi)->s_ops->allocate_segment(sbi, type, true);
1208 	locate_dirty_segment(sbi, old_segno);
1209 }
1210 
1211 void allocate_new_segments(struct f2fs_sb_info *sbi)
1212 {
1213 	int i;
1214 
1215 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)
1216 		__allocate_new_segments(sbi, i);
1217 }
1218 
1219 static const struct segment_allocation default_salloc_ops = {
1220 	.allocate_segment = allocate_segment_by_default,
1221 };
1222 
1223 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
1224 {
1225 	__u64 start = F2FS_BYTES_TO_BLK(range->start);
1226 	__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
1227 	unsigned int start_segno, end_segno;
1228 	struct cp_control cpc;
1229 	int err = 0;
1230 
1231 	if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
1232 		return -EINVAL;
1233 
1234 	cpc.trimmed = 0;
1235 	if (end <= MAIN_BLKADDR(sbi))
1236 		goto out;
1237 
1238 	/* start/end segment number in main_area */
1239 	start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
1240 	end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
1241 						GET_SEGNO(sbi, end);
1242 	cpc.reason = CP_DISCARD;
1243 	cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
1244 
1245 	/* do checkpoint to issue discard commands safely */
1246 	for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
1247 		cpc.trim_start = start_segno;
1248 
1249 		if (sbi->discard_blks == 0)
1250 			break;
1251 		else if (sbi->discard_blks < BATCHED_TRIM_BLOCKS(sbi))
1252 			cpc.trim_end = end_segno;
1253 		else
1254 			cpc.trim_end = min_t(unsigned int,
1255 				rounddown(start_segno +
1256 				BATCHED_TRIM_SEGMENTS(sbi),
1257 				sbi->segs_per_sec) - 1, end_segno);
1258 
1259 		mutex_lock(&sbi->gc_mutex);
1260 		err = write_checkpoint(sbi, &cpc);
1261 		mutex_unlock(&sbi->gc_mutex);
1262 	}
1263 out:
1264 	range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
1265 	return err;
1266 }
1267 
1268 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
1269 {
1270 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1271 	if (curseg->next_blkoff < sbi->blocks_per_seg)
1272 		return true;
1273 	return false;
1274 }
1275 
1276 static int __get_segment_type_2(struct page *page, enum page_type p_type)
1277 {
1278 	if (p_type == DATA)
1279 		return CURSEG_HOT_DATA;
1280 	else
1281 		return CURSEG_HOT_NODE;
1282 }
1283 
1284 static int __get_segment_type_4(struct page *page, enum page_type p_type)
1285 {
1286 	if (p_type == DATA) {
1287 		struct inode *inode = page->mapping->host;
1288 
1289 		if (S_ISDIR(inode->i_mode))
1290 			return CURSEG_HOT_DATA;
1291 		else
1292 			return CURSEG_COLD_DATA;
1293 	} else {
1294 		if (IS_DNODE(page) && is_cold_node(page))
1295 			return CURSEG_WARM_NODE;
1296 		else
1297 			return CURSEG_COLD_NODE;
1298 	}
1299 }
1300 
1301 static int __get_segment_type_6(struct page *page, enum page_type p_type)
1302 {
1303 	if (p_type == DATA) {
1304 		struct inode *inode = page->mapping->host;
1305 
1306 		if (S_ISDIR(inode->i_mode))
1307 			return CURSEG_HOT_DATA;
1308 		else if (is_cold_data(page) || file_is_cold(inode))
1309 			return CURSEG_COLD_DATA;
1310 		else
1311 			return CURSEG_WARM_DATA;
1312 	} else {
1313 		if (IS_DNODE(page))
1314 			return is_cold_node(page) ? CURSEG_WARM_NODE :
1315 						CURSEG_HOT_NODE;
1316 		else
1317 			return CURSEG_COLD_NODE;
1318 	}
1319 }
1320 
1321 static int __get_segment_type(struct page *page, enum page_type p_type)
1322 {
1323 	switch (F2FS_P_SB(page)->active_logs) {
1324 	case 2:
1325 		return __get_segment_type_2(page, p_type);
1326 	case 4:
1327 		return __get_segment_type_4(page, p_type);
1328 	}
1329 	/* NR_CURSEG_TYPE(6) logs by default */
1330 	f2fs_bug_on(F2FS_P_SB(page),
1331 		F2FS_P_SB(page)->active_logs != NR_CURSEG_TYPE);
1332 	return __get_segment_type_6(page, p_type);
1333 }
1334 
1335 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
1336 		block_t old_blkaddr, block_t *new_blkaddr,
1337 		struct f2fs_summary *sum, int type)
1338 {
1339 	struct sit_info *sit_i = SIT_I(sbi);
1340 	struct curseg_info *curseg;
1341 	bool direct_io = (type == CURSEG_DIRECT_IO);
1342 
1343 	type = direct_io ? CURSEG_WARM_DATA : type;
1344 
1345 	curseg = CURSEG_I(sbi, type);
1346 
1347 	mutex_lock(&curseg->curseg_mutex);
1348 	mutex_lock(&sit_i->sentry_lock);
1349 
1350 	/* direct_io'ed data is aligned to the segment for better performance */
1351 	if (direct_io && curseg->next_blkoff &&
1352 				!has_not_enough_free_secs(sbi, 0))
1353 		__allocate_new_segments(sbi, type);
1354 
1355 	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
1356 
1357 	/*
1358 	 * __add_sum_entry should be resided under the curseg_mutex
1359 	 * because, this function updates a summary entry in the
1360 	 * current summary block.
1361 	 */
1362 	__add_sum_entry(sbi, type, sum);
1363 
1364 	__refresh_next_blkoff(sbi, curseg);
1365 
1366 	stat_inc_block_count(sbi, curseg);
1367 
1368 	if (!__has_curseg_space(sbi, type))
1369 		sit_i->s_ops->allocate_segment(sbi, type, false);
1370 	/*
1371 	 * SIT information should be updated before segment allocation,
1372 	 * since SSR needs latest valid block information.
1373 	 */
1374 	refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
1375 
1376 	mutex_unlock(&sit_i->sentry_lock);
1377 
1378 	if (page && IS_NODESEG(type))
1379 		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
1380 
1381 	mutex_unlock(&curseg->curseg_mutex);
1382 }
1383 
1384 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
1385 {
1386 	int type = __get_segment_type(fio->page, fio->type);
1387 
1388 	allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
1389 					&fio->new_blkaddr, sum, type);
1390 
1391 	/* writeout dirty page into bdev */
1392 	f2fs_submit_page_mbio(fio);
1393 }
1394 
1395 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
1396 {
1397 	struct f2fs_io_info fio = {
1398 		.sbi = sbi,
1399 		.type = META,
1400 		.rw = WRITE_SYNC | REQ_META | REQ_PRIO,
1401 		.old_blkaddr = page->index,
1402 		.new_blkaddr = page->index,
1403 		.page = page,
1404 		.encrypted_page = NULL,
1405 	};
1406 
1407 	if (unlikely(page->index >= MAIN_BLKADDR(sbi)))
1408 		fio.rw &= ~REQ_META;
1409 
1410 	set_page_writeback(page);
1411 	f2fs_submit_page_mbio(&fio);
1412 }
1413 
1414 void write_node_page(unsigned int nid, struct f2fs_io_info *fio)
1415 {
1416 	struct f2fs_summary sum;
1417 
1418 	set_summary(&sum, nid, 0, 0);
1419 	do_write_page(&sum, fio);
1420 }
1421 
1422 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio)
1423 {
1424 	struct f2fs_sb_info *sbi = fio->sbi;
1425 	struct f2fs_summary sum;
1426 	struct node_info ni;
1427 
1428 	f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
1429 	get_node_info(sbi, dn->nid, &ni);
1430 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
1431 	do_write_page(&sum, fio);
1432 	f2fs_update_data_blkaddr(dn, fio->new_blkaddr);
1433 }
1434 
1435 void rewrite_data_page(struct f2fs_io_info *fio)
1436 {
1437 	fio->new_blkaddr = fio->old_blkaddr;
1438 	stat_inc_inplace_blocks(fio->sbi);
1439 	f2fs_submit_page_mbio(fio);
1440 }
1441 
1442 void __f2fs_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
1443 				block_t old_blkaddr, block_t new_blkaddr,
1444 				bool recover_curseg, bool recover_newaddr)
1445 {
1446 	struct sit_info *sit_i = SIT_I(sbi);
1447 	struct curseg_info *curseg;
1448 	unsigned int segno, old_cursegno;
1449 	struct seg_entry *se;
1450 	int type;
1451 	unsigned short old_blkoff;
1452 
1453 	segno = GET_SEGNO(sbi, new_blkaddr);
1454 	se = get_seg_entry(sbi, segno);
1455 	type = se->type;
1456 
1457 	if (!recover_curseg) {
1458 		/* for recovery flow */
1459 		if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
1460 			if (old_blkaddr == NULL_ADDR)
1461 				type = CURSEG_COLD_DATA;
1462 			else
1463 				type = CURSEG_WARM_DATA;
1464 		}
1465 	} else {
1466 		if (!IS_CURSEG(sbi, segno))
1467 			type = CURSEG_WARM_DATA;
1468 	}
1469 
1470 	curseg = CURSEG_I(sbi, type);
1471 
1472 	mutex_lock(&curseg->curseg_mutex);
1473 	mutex_lock(&sit_i->sentry_lock);
1474 
1475 	old_cursegno = curseg->segno;
1476 	old_blkoff = curseg->next_blkoff;
1477 
1478 	/* change the current segment */
1479 	if (segno != curseg->segno) {
1480 		curseg->next_segno = segno;
1481 		change_curseg(sbi, type, true);
1482 	}
1483 
1484 	curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
1485 	__add_sum_entry(sbi, type, sum);
1486 
1487 	if (!recover_curseg || recover_newaddr)
1488 		update_sit_entry(sbi, new_blkaddr, 1);
1489 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
1490 		update_sit_entry(sbi, old_blkaddr, -1);
1491 
1492 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
1493 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new_blkaddr));
1494 
1495 	locate_dirty_segment(sbi, old_cursegno);
1496 
1497 	if (recover_curseg) {
1498 		if (old_cursegno != curseg->segno) {
1499 			curseg->next_segno = old_cursegno;
1500 			change_curseg(sbi, type, true);
1501 		}
1502 		curseg->next_blkoff = old_blkoff;
1503 	}
1504 
1505 	mutex_unlock(&sit_i->sentry_lock);
1506 	mutex_unlock(&curseg->curseg_mutex);
1507 }
1508 
1509 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
1510 				block_t old_addr, block_t new_addr,
1511 				unsigned char version, bool recover_curseg,
1512 				bool recover_newaddr)
1513 {
1514 	struct f2fs_summary sum;
1515 
1516 	set_summary(&sum, dn->nid, dn->ofs_in_node, version);
1517 
1518 	__f2fs_replace_block(sbi, &sum, old_addr, new_addr,
1519 					recover_curseg, recover_newaddr);
1520 
1521 	f2fs_update_data_blkaddr(dn, new_addr);
1522 }
1523 
1524 void f2fs_wait_on_page_writeback(struct page *page,
1525 				enum page_type type, bool ordered)
1526 {
1527 	if (PageWriteback(page)) {
1528 		struct f2fs_sb_info *sbi = F2FS_P_SB(page);
1529 
1530 		f2fs_submit_merged_bio_cond(sbi, NULL, page, 0, type, WRITE);
1531 		if (ordered)
1532 			wait_on_page_writeback(page);
1533 		else
1534 			wait_for_stable_page(page);
1535 	}
1536 }
1537 
1538 void f2fs_wait_on_encrypted_page_writeback(struct f2fs_sb_info *sbi,
1539 							block_t blkaddr)
1540 {
1541 	struct page *cpage;
1542 
1543 	if (blkaddr == NEW_ADDR)
1544 		return;
1545 
1546 	f2fs_bug_on(sbi, blkaddr == NULL_ADDR);
1547 
1548 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
1549 	if (cpage) {
1550 		f2fs_wait_on_page_writeback(cpage, DATA, true);
1551 		f2fs_put_page(cpage, 1);
1552 	}
1553 }
1554 
1555 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
1556 {
1557 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1558 	struct curseg_info *seg_i;
1559 	unsigned char *kaddr;
1560 	struct page *page;
1561 	block_t start;
1562 	int i, j, offset;
1563 
1564 	start = start_sum_block(sbi);
1565 
1566 	page = get_meta_page(sbi, start++);
1567 	kaddr = (unsigned char *)page_address(page);
1568 
1569 	/* Step 1: restore nat cache */
1570 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1571 	memcpy(seg_i->journal, kaddr, SUM_JOURNAL_SIZE);
1572 
1573 	/* Step 2: restore sit cache */
1574 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1575 	memcpy(seg_i->journal, kaddr + SUM_JOURNAL_SIZE, SUM_JOURNAL_SIZE);
1576 	offset = 2 * SUM_JOURNAL_SIZE;
1577 
1578 	/* Step 3: restore summary entries */
1579 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1580 		unsigned short blk_off;
1581 		unsigned int segno;
1582 
1583 		seg_i = CURSEG_I(sbi, i);
1584 		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
1585 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
1586 		seg_i->next_segno = segno;
1587 		reset_curseg(sbi, i, 0);
1588 		seg_i->alloc_type = ckpt->alloc_type[i];
1589 		seg_i->next_blkoff = blk_off;
1590 
1591 		if (seg_i->alloc_type == SSR)
1592 			blk_off = sbi->blocks_per_seg;
1593 
1594 		for (j = 0; j < blk_off; j++) {
1595 			struct f2fs_summary *s;
1596 			s = (struct f2fs_summary *)(kaddr + offset);
1597 			seg_i->sum_blk->entries[j] = *s;
1598 			offset += SUMMARY_SIZE;
1599 			if (offset + SUMMARY_SIZE <= PAGE_SIZE -
1600 						SUM_FOOTER_SIZE)
1601 				continue;
1602 
1603 			f2fs_put_page(page, 1);
1604 			page = NULL;
1605 
1606 			page = get_meta_page(sbi, start++);
1607 			kaddr = (unsigned char *)page_address(page);
1608 			offset = 0;
1609 		}
1610 	}
1611 	f2fs_put_page(page, 1);
1612 	return 0;
1613 }
1614 
1615 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
1616 {
1617 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1618 	struct f2fs_summary_block *sum;
1619 	struct curseg_info *curseg;
1620 	struct page *new;
1621 	unsigned short blk_off;
1622 	unsigned int segno = 0;
1623 	block_t blk_addr = 0;
1624 
1625 	/* get segment number and block addr */
1626 	if (IS_DATASEG(type)) {
1627 		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
1628 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
1629 							CURSEG_HOT_DATA]);
1630 		if (__exist_node_summaries(sbi))
1631 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
1632 		else
1633 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
1634 	} else {
1635 		segno = le32_to_cpu(ckpt->cur_node_segno[type -
1636 							CURSEG_HOT_NODE]);
1637 		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
1638 							CURSEG_HOT_NODE]);
1639 		if (__exist_node_summaries(sbi))
1640 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
1641 							type - CURSEG_HOT_NODE);
1642 		else
1643 			blk_addr = GET_SUM_BLOCK(sbi, segno);
1644 	}
1645 
1646 	new = get_meta_page(sbi, blk_addr);
1647 	sum = (struct f2fs_summary_block *)page_address(new);
1648 
1649 	if (IS_NODESEG(type)) {
1650 		if (__exist_node_summaries(sbi)) {
1651 			struct f2fs_summary *ns = &sum->entries[0];
1652 			int i;
1653 			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
1654 				ns->version = 0;
1655 				ns->ofs_in_node = 0;
1656 			}
1657 		} else {
1658 			int err;
1659 
1660 			err = restore_node_summary(sbi, segno, sum);
1661 			if (err) {
1662 				f2fs_put_page(new, 1);
1663 				return err;
1664 			}
1665 		}
1666 	}
1667 
1668 	/* set uncompleted segment to curseg */
1669 	curseg = CURSEG_I(sbi, type);
1670 	mutex_lock(&curseg->curseg_mutex);
1671 
1672 	/* update journal info */
1673 	down_write(&curseg->journal_rwsem);
1674 	memcpy(curseg->journal, &sum->journal, SUM_JOURNAL_SIZE);
1675 	up_write(&curseg->journal_rwsem);
1676 
1677 	memcpy(curseg->sum_blk->entries, sum->entries, SUM_ENTRY_SIZE);
1678 	memcpy(&curseg->sum_blk->footer, &sum->footer, SUM_FOOTER_SIZE);
1679 	curseg->next_segno = segno;
1680 	reset_curseg(sbi, type, 0);
1681 	curseg->alloc_type = ckpt->alloc_type[type];
1682 	curseg->next_blkoff = blk_off;
1683 	mutex_unlock(&curseg->curseg_mutex);
1684 	f2fs_put_page(new, 1);
1685 	return 0;
1686 }
1687 
1688 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
1689 {
1690 	int type = CURSEG_HOT_DATA;
1691 	int err;
1692 
1693 	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG)) {
1694 		int npages = npages_for_summary_flush(sbi, true);
1695 
1696 		if (npages >= 2)
1697 			ra_meta_pages(sbi, start_sum_block(sbi), npages,
1698 							META_CP, true);
1699 
1700 		/* restore for compacted data summary */
1701 		if (read_compacted_summaries(sbi))
1702 			return -EINVAL;
1703 		type = CURSEG_HOT_NODE;
1704 	}
1705 
1706 	if (__exist_node_summaries(sbi))
1707 		ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
1708 					NR_CURSEG_TYPE - type, META_CP, true);
1709 
1710 	for (; type <= CURSEG_COLD_NODE; type++) {
1711 		err = read_normal_summaries(sbi, type);
1712 		if (err)
1713 			return err;
1714 	}
1715 
1716 	return 0;
1717 }
1718 
1719 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
1720 {
1721 	struct page *page;
1722 	unsigned char *kaddr;
1723 	struct f2fs_summary *summary;
1724 	struct curseg_info *seg_i;
1725 	int written_size = 0;
1726 	int i, j;
1727 
1728 	page = grab_meta_page(sbi, blkaddr++);
1729 	kaddr = (unsigned char *)page_address(page);
1730 
1731 	/* Step 1: write nat cache */
1732 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1733 	memcpy(kaddr, seg_i->journal, SUM_JOURNAL_SIZE);
1734 	written_size += SUM_JOURNAL_SIZE;
1735 
1736 	/* Step 2: write sit cache */
1737 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1738 	memcpy(kaddr + written_size, seg_i->journal, SUM_JOURNAL_SIZE);
1739 	written_size += SUM_JOURNAL_SIZE;
1740 
1741 	/* Step 3: write summary entries */
1742 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1743 		unsigned short blkoff;
1744 		seg_i = CURSEG_I(sbi, i);
1745 		if (sbi->ckpt->alloc_type[i] == SSR)
1746 			blkoff = sbi->blocks_per_seg;
1747 		else
1748 			blkoff = curseg_blkoff(sbi, i);
1749 
1750 		for (j = 0; j < blkoff; j++) {
1751 			if (!page) {
1752 				page = grab_meta_page(sbi, blkaddr++);
1753 				kaddr = (unsigned char *)page_address(page);
1754 				written_size = 0;
1755 			}
1756 			summary = (struct f2fs_summary *)(kaddr + written_size);
1757 			*summary = seg_i->sum_blk->entries[j];
1758 			written_size += SUMMARY_SIZE;
1759 
1760 			if (written_size + SUMMARY_SIZE <= PAGE_SIZE -
1761 							SUM_FOOTER_SIZE)
1762 				continue;
1763 
1764 			set_page_dirty(page);
1765 			f2fs_put_page(page, 1);
1766 			page = NULL;
1767 		}
1768 	}
1769 	if (page) {
1770 		set_page_dirty(page);
1771 		f2fs_put_page(page, 1);
1772 	}
1773 }
1774 
1775 static void write_normal_summaries(struct f2fs_sb_info *sbi,
1776 					block_t blkaddr, int type)
1777 {
1778 	int i, end;
1779 	if (IS_DATASEG(type))
1780 		end = type + NR_CURSEG_DATA_TYPE;
1781 	else
1782 		end = type + NR_CURSEG_NODE_TYPE;
1783 
1784 	for (i = type; i < end; i++)
1785 		write_current_sum_page(sbi, i, blkaddr + (i - type));
1786 }
1787 
1788 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1789 {
1790 	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG))
1791 		write_compacted_summaries(sbi, start_blk);
1792 	else
1793 		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
1794 }
1795 
1796 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1797 {
1798 	write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
1799 }
1800 
1801 int lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
1802 					unsigned int val, int alloc)
1803 {
1804 	int i;
1805 
1806 	if (type == NAT_JOURNAL) {
1807 		for (i = 0; i < nats_in_cursum(journal); i++) {
1808 			if (le32_to_cpu(nid_in_journal(journal, i)) == val)
1809 				return i;
1810 		}
1811 		if (alloc && __has_cursum_space(journal, 1, NAT_JOURNAL))
1812 			return update_nats_in_cursum(journal, 1);
1813 	} else if (type == SIT_JOURNAL) {
1814 		for (i = 0; i < sits_in_cursum(journal); i++)
1815 			if (le32_to_cpu(segno_in_journal(journal, i)) == val)
1816 				return i;
1817 		if (alloc && __has_cursum_space(journal, 1, SIT_JOURNAL))
1818 			return update_sits_in_cursum(journal, 1);
1819 	}
1820 	return -1;
1821 }
1822 
1823 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
1824 					unsigned int segno)
1825 {
1826 	return get_meta_page(sbi, current_sit_addr(sbi, segno));
1827 }
1828 
1829 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
1830 					unsigned int start)
1831 {
1832 	struct sit_info *sit_i = SIT_I(sbi);
1833 	struct page *src_page, *dst_page;
1834 	pgoff_t src_off, dst_off;
1835 	void *src_addr, *dst_addr;
1836 
1837 	src_off = current_sit_addr(sbi, start);
1838 	dst_off = next_sit_addr(sbi, src_off);
1839 
1840 	/* get current sit block page without lock */
1841 	src_page = get_meta_page(sbi, src_off);
1842 	dst_page = grab_meta_page(sbi, dst_off);
1843 	f2fs_bug_on(sbi, PageDirty(src_page));
1844 
1845 	src_addr = page_address(src_page);
1846 	dst_addr = page_address(dst_page);
1847 	memcpy(dst_addr, src_addr, PAGE_SIZE);
1848 
1849 	set_page_dirty(dst_page);
1850 	f2fs_put_page(src_page, 1);
1851 
1852 	set_to_next_sit(sit_i, start);
1853 
1854 	return dst_page;
1855 }
1856 
1857 static struct sit_entry_set *grab_sit_entry_set(void)
1858 {
1859 	struct sit_entry_set *ses =
1860 			f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
1861 
1862 	ses->entry_cnt = 0;
1863 	INIT_LIST_HEAD(&ses->set_list);
1864 	return ses;
1865 }
1866 
1867 static void release_sit_entry_set(struct sit_entry_set *ses)
1868 {
1869 	list_del(&ses->set_list);
1870 	kmem_cache_free(sit_entry_set_slab, ses);
1871 }
1872 
1873 static void adjust_sit_entry_set(struct sit_entry_set *ses,
1874 						struct list_head *head)
1875 {
1876 	struct sit_entry_set *next = ses;
1877 
1878 	if (list_is_last(&ses->set_list, head))
1879 		return;
1880 
1881 	list_for_each_entry_continue(next, head, set_list)
1882 		if (ses->entry_cnt <= next->entry_cnt)
1883 			break;
1884 
1885 	list_move_tail(&ses->set_list, &next->set_list);
1886 }
1887 
1888 static void add_sit_entry(unsigned int segno, struct list_head *head)
1889 {
1890 	struct sit_entry_set *ses;
1891 	unsigned int start_segno = START_SEGNO(segno);
1892 
1893 	list_for_each_entry(ses, head, set_list) {
1894 		if (ses->start_segno == start_segno) {
1895 			ses->entry_cnt++;
1896 			adjust_sit_entry_set(ses, head);
1897 			return;
1898 		}
1899 	}
1900 
1901 	ses = grab_sit_entry_set();
1902 
1903 	ses->start_segno = start_segno;
1904 	ses->entry_cnt++;
1905 	list_add(&ses->set_list, head);
1906 }
1907 
1908 static void add_sits_in_set(struct f2fs_sb_info *sbi)
1909 {
1910 	struct f2fs_sm_info *sm_info = SM_I(sbi);
1911 	struct list_head *set_list = &sm_info->sit_entry_set;
1912 	unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
1913 	unsigned int segno;
1914 
1915 	for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
1916 		add_sit_entry(segno, set_list);
1917 }
1918 
1919 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
1920 {
1921 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1922 	struct f2fs_journal *journal = curseg->journal;
1923 	int i;
1924 
1925 	down_write(&curseg->journal_rwsem);
1926 	for (i = 0; i < sits_in_cursum(journal); i++) {
1927 		unsigned int segno;
1928 		bool dirtied;
1929 
1930 		segno = le32_to_cpu(segno_in_journal(journal, i));
1931 		dirtied = __mark_sit_entry_dirty(sbi, segno);
1932 
1933 		if (!dirtied)
1934 			add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
1935 	}
1936 	update_sits_in_cursum(journal, -i);
1937 	up_write(&curseg->journal_rwsem);
1938 }
1939 
1940 /*
1941  * CP calls this function, which flushes SIT entries including sit_journal,
1942  * and moves prefree segs to free segs.
1943  */
1944 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1945 {
1946 	struct sit_info *sit_i = SIT_I(sbi);
1947 	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
1948 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1949 	struct f2fs_journal *journal = curseg->journal;
1950 	struct sit_entry_set *ses, *tmp;
1951 	struct list_head *head = &SM_I(sbi)->sit_entry_set;
1952 	bool to_journal = true;
1953 	struct seg_entry *se;
1954 
1955 	mutex_lock(&sit_i->sentry_lock);
1956 
1957 	if (!sit_i->dirty_sentries)
1958 		goto out;
1959 
1960 	/*
1961 	 * add and account sit entries of dirty bitmap in sit entry
1962 	 * set temporarily
1963 	 */
1964 	add_sits_in_set(sbi);
1965 
1966 	/*
1967 	 * if there are no enough space in journal to store dirty sit
1968 	 * entries, remove all entries from journal and add and account
1969 	 * them in sit entry set.
1970 	 */
1971 	if (!__has_cursum_space(journal, sit_i->dirty_sentries, SIT_JOURNAL))
1972 		remove_sits_in_journal(sbi);
1973 
1974 	/*
1975 	 * there are two steps to flush sit entries:
1976 	 * #1, flush sit entries to journal in current cold data summary block.
1977 	 * #2, flush sit entries to sit page.
1978 	 */
1979 	list_for_each_entry_safe(ses, tmp, head, set_list) {
1980 		struct page *page = NULL;
1981 		struct f2fs_sit_block *raw_sit = NULL;
1982 		unsigned int start_segno = ses->start_segno;
1983 		unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
1984 						(unsigned long)MAIN_SEGS(sbi));
1985 		unsigned int segno = start_segno;
1986 
1987 		if (to_journal &&
1988 			!__has_cursum_space(journal, ses->entry_cnt, SIT_JOURNAL))
1989 			to_journal = false;
1990 
1991 		if (to_journal) {
1992 			down_write(&curseg->journal_rwsem);
1993 		} else {
1994 			page = get_next_sit_page(sbi, start_segno);
1995 			raw_sit = page_address(page);
1996 		}
1997 
1998 		/* flush dirty sit entries in region of current sit set */
1999 		for_each_set_bit_from(segno, bitmap, end) {
2000 			int offset, sit_offset;
2001 
2002 			se = get_seg_entry(sbi, segno);
2003 
2004 			/* add discard candidates */
2005 			if (cpc->reason != CP_DISCARD) {
2006 				cpc->trim_start = segno;
2007 				add_discard_addrs(sbi, cpc);
2008 			}
2009 
2010 			if (to_journal) {
2011 				offset = lookup_journal_in_cursum(journal,
2012 							SIT_JOURNAL, segno, 1);
2013 				f2fs_bug_on(sbi, offset < 0);
2014 				segno_in_journal(journal, offset) =
2015 							cpu_to_le32(segno);
2016 				seg_info_to_raw_sit(se,
2017 					&sit_in_journal(journal, offset));
2018 			} else {
2019 				sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
2020 				seg_info_to_raw_sit(se,
2021 						&raw_sit->entries[sit_offset]);
2022 			}
2023 
2024 			__clear_bit(segno, bitmap);
2025 			sit_i->dirty_sentries--;
2026 			ses->entry_cnt--;
2027 		}
2028 
2029 		if (to_journal)
2030 			up_write(&curseg->journal_rwsem);
2031 		else
2032 			f2fs_put_page(page, 1);
2033 
2034 		f2fs_bug_on(sbi, ses->entry_cnt);
2035 		release_sit_entry_set(ses);
2036 	}
2037 
2038 	f2fs_bug_on(sbi, !list_empty(head));
2039 	f2fs_bug_on(sbi, sit_i->dirty_sentries);
2040 out:
2041 	if (cpc->reason == CP_DISCARD) {
2042 		for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
2043 			add_discard_addrs(sbi, cpc);
2044 	}
2045 	mutex_unlock(&sit_i->sentry_lock);
2046 
2047 	set_prefree_as_free_segments(sbi);
2048 }
2049 
2050 static int build_sit_info(struct f2fs_sb_info *sbi)
2051 {
2052 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2053 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2054 	struct sit_info *sit_i;
2055 	unsigned int sit_segs, start;
2056 	char *src_bitmap, *dst_bitmap;
2057 	unsigned int bitmap_size;
2058 
2059 	/* allocate memory for SIT information */
2060 	sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
2061 	if (!sit_i)
2062 		return -ENOMEM;
2063 
2064 	SM_I(sbi)->sit_info = sit_i;
2065 
2066 	sit_i->sentries = f2fs_kvzalloc(MAIN_SEGS(sbi) *
2067 					sizeof(struct seg_entry), GFP_KERNEL);
2068 	if (!sit_i->sentries)
2069 		return -ENOMEM;
2070 
2071 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2072 	sit_i->dirty_sentries_bitmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2073 	if (!sit_i->dirty_sentries_bitmap)
2074 		return -ENOMEM;
2075 
2076 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2077 		sit_i->sentries[start].cur_valid_map
2078 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2079 		sit_i->sentries[start].ckpt_valid_map
2080 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2081 		sit_i->sentries[start].discard_map
2082 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2083 		if (!sit_i->sentries[start].cur_valid_map ||
2084 				!sit_i->sentries[start].ckpt_valid_map ||
2085 				!sit_i->sentries[start].discard_map)
2086 			return -ENOMEM;
2087 	}
2088 
2089 	sit_i->tmp_map = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2090 	if (!sit_i->tmp_map)
2091 		return -ENOMEM;
2092 
2093 	if (sbi->segs_per_sec > 1) {
2094 		sit_i->sec_entries = f2fs_kvzalloc(MAIN_SECS(sbi) *
2095 					sizeof(struct sec_entry), GFP_KERNEL);
2096 		if (!sit_i->sec_entries)
2097 			return -ENOMEM;
2098 	}
2099 
2100 	/* get information related with SIT */
2101 	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
2102 
2103 	/* setup SIT bitmap from ckeckpoint pack */
2104 	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
2105 	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
2106 
2107 	dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
2108 	if (!dst_bitmap)
2109 		return -ENOMEM;
2110 
2111 	/* init SIT information */
2112 	sit_i->s_ops = &default_salloc_ops;
2113 
2114 	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
2115 	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
2116 	sit_i->written_valid_blocks = le64_to_cpu(ckpt->valid_block_count);
2117 	sit_i->sit_bitmap = dst_bitmap;
2118 	sit_i->bitmap_size = bitmap_size;
2119 	sit_i->dirty_sentries = 0;
2120 	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
2121 	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
2122 	sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
2123 	mutex_init(&sit_i->sentry_lock);
2124 	return 0;
2125 }
2126 
2127 static int build_free_segmap(struct f2fs_sb_info *sbi)
2128 {
2129 	struct free_segmap_info *free_i;
2130 	unsigned int bitmap_size, sec_bitmap_size;
2131 
2132 	/* allocate memory for free segmap information */
2133 	free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
2134 	if (!free_i)
2135 		return -ENOMEM;
2136 
2137 	SM_I(sbi)->free_info = free_i;
2138 
2139 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2140 	free_i->free_segmap = f2fs_kvmalloc(bitmap_size, GFP_KERNEL);
2141 	if (!free_i->free_segmap)
2142 		return -ENOMEM;
2143 
2144 	sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2145 	free_i->free_secmap = f2fs_kvmalloc(sec_bitmap_size, GFP_KERNEL);
2146 	if (!free_i->free_secmap)
2147 		return -ENOMEM;
2148 
2149 	/* set all segments as dirty temporarily */
2150 	memset(free_i->free_segmap, 0xff, bitmap_size);
2151 	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
2152 
2153 	/* init free segmap information */
2154 	free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
2155 	free_i->free_segments = 0;
2156 	free_i->free_sections = 0;
2157 	spin_lock_init(&free_i->segmap_lock);
2158 	return 0;
2159 }
2160 
2161 static int build_curseg(struct f2fs_sb_info *sbi)
2162 {
2163 	struct curseg_info *array;
2164 	int i;
2165 
2166 	array = kcalloc(NR_CURSEG_TYPE, sizeof(*array), GFP_KERNEL);
2167 	if (!array)
2168 		return -ENOMEM;
2169 
2170 	SM_I(sbi)->curseg_array = array;
2171 
2172 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
2173 		mutex_init(&array[i].curseg_mutex);
2174 		array[i].sum_blk = kzalloc(PAGE_SIZE, GFP_KERNEL);
2175 		if (!array[i].sum_blk)
2176 			return -ENOMEM;
2177 		init_rwsem(&array[i].journal_rwsem);
2178 		array[i].journal = kzalloc(sizeof(struct f2fs_journal),
2179 							GFP_KERNEL);
2180 		if (!array[i].journal)
2181 			return -ENOMEM;
2182 		array[i].segno = NULL_SEGNO;
2183 		array[i].next_blkoff = 0;
2184 	}
2185 	return restore_curseg_summaries(sbi);
2186 }
2187 
2188 static void build_sit_entries(struct f2fs_sb_info *sbi)
2189 {
2190 	struct sit_info *sit_i = SIT_I(sbi);
2191 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2192 	struct f2fs_journal *journal = curseg->journal;
2193 	int sit_blk_cnt = SIT_BLK_CNT(sbi);
2194 	unsigned int i, start, end;
2195 	unsigned int readed, start_blk = 0;
2196 	int nrpages = MAX_BIO_BLOCKS(sbi) * 8;
2197 
2198 	do {
2199 		readed = ra_meta_pages(sbi, start_blk, nrpages, META_SIT, true);
2200 
2201 		start = start_blk * sit_i->sents_per_block;
2202 		end = (start_blk + readed) * sit_i->sents_per_block;
2203 
2204 		for (; start < end && start < MAIN_SEGS(sbi); start++) {
2205 			struct seg_entry *se = &sit_i->sentries[start];
2206 			struct f2fs_sit_block *sit_blk;
2207 			struct f2fs_sit_entry sit;
2208 			struct page *page;
2209 
2210 			down_read(&curseg->journal_rwsem);
2211 			for (i = 0; i < sits_in_cursum(journal); i++) {
2212 				if (le32_to_cpu(segno_in_journal(journal, i))
2213 								== start) {
2214 					sit = sit_in_journal(journal, i);
2215 					up_read(&curseg->journal_rwsem);
2216 					goto got_it;
2217 				}
2218 			}
2219 			up_read(&curseg->journal_rwsem);
2220 
2221 			page = get_current_sit_page(sbi, start);
2222 			sit_blk = (struct f2fs_sit_block *)page_address(page);
2223 			sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
2224 			f2fs_put_page(page, 1);
2225 got_it:
2226 			check_block_count(sbi, start, &sit);
2227 			seg_info_from_raw_sit(se, &sit);
2228 
2229 			/* build discard map only one time */
2230 			memcpy(se->discard_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
2231 			sbi->discard_blks += sbi->blocks_per_seg - se->valid_blocks;
2232 
2233 			if (sbi->segs_per_sec > 1) {
2234 				struct sec_entry *e = get_sec_entry(sbi, start);
2235 				e->valid_blocks += se->valid_blocks;
2236 			}
2237 		}
2238 		start_blk += readed;
2239 	} while (start_blk < sit_blk_cnt);
2240 }
2241 
2242 static void init_free_segmap(struct f2fs_sb_info *sbi)
2243 {
2244 	unsigned int start;
2245 	int type;
2246 
2247 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2248 		struct seg_entry *sentry = get_seg_entry(sbi, start);
2249 		if (!sentry->valid_blocks)
2250 			__set_free(sbi, start);
2251 	}
2252 
2253 	/* set use the current segments */
2254 	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
2255 		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
2256 		__set_test_and_inuse(sbi, curseg_t->segno);
2257 	}
2258 }
2259 
2260 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
2261 {
2262 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2263 	struct free_segmap_info *free_i = FREE_I(sbi);
2264 	unsigned int segno = 0, offset = 0;
2265 	unsigned short valid_blocks;
2266 
2267 	while (1) {
2268 		/* find dirty segment based on free segmap */
2269 		segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
2270 		if (segno >= MAIN_SEGS(sbi))
2271 			break;
2272 		offset = segno + 1;
2273 		valid_blocks = get_valid_blocks(sbi, segno, 0);
2274 		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
2275 			continue;
2276 		if (valid_blocks > sbi->blocks_per_seg) {
2277 			f2fs_bug_on(sbi, 1);
2278 			continue;
2279 		}
2280 		mutex_lock(&dirty_i->seglist_lock);
2281 		__locate_dirty_segment(sbi, segno, DIRTY);
2282 		mutex_unlock(&dirty_i->seglist_lock);
2283 	}
2284 }
2285 
2286 static int init_victim_secmap(struct f2fs_sb_info *sbi)
2287 {
2288 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2289 	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2290 
2291 	dirty_i->victim_secmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2292 	if (!dirty_i->victim_secmap)
2293 		return -ENOMEM;
2294 	return 0;
2295 }
2296 
2297 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
2298 {
2299 	struct dirty_seglist_info *dirty_i;
2300 	unsigned int bitmap_size, i;
2301 
2302 	/* allocate memory for dirty segments list information */
2303 	dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
2304 	if (!dirty_i)
2305 		return -ENOMEM;
2306 
2307 	SM_I(sbi)->dirty_info = dirty_i;
2308 	mutex_init(&dirty_i->seglist_lock);
2309 
2310 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2311 
2312 	for (i = 0; i < NR_DIRTY_TYPE; i++) {
2313 		dirty_i->dirty_segmap[i] = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2314 		if (!dirty_i->dirty_segmap[i])
2315 			return -ENOMEM;
2316 	}
2317 
2318 	init_dirty_segmap(sbi);
2319 	return init_victim_secmap(sbi);
2320 }
2321 
2322 /*
2323  * Update min, max modified time for cost-benefit GC algorithm
2324  */
2325 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
2326 {
2327 	struct sit_info *sit_i = SIT_I(sbi);
2328 	unsigned int segno;
2329 
2330 	mutex_lock(&sit_i->sentry_lock);
2331 
2332 	sit_i->min_mtime = LLONG_MAX;
2333 
2334 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
2335 		unsigned int i;
2336 		unsigned long long mtime = 0;
2337 
2338 		for (i = 0; i < sbi->segs_per_sec; i++)
2339 			mtime += get_seg_entry(sbi, segno + i)->mtime;
2340 
2341 		mtime = div_u64(mtime, sbi->segs_per_sec);
2342 
2343 		if (sit_i->min_mtime > mtime)
2344 			sit_i->min_mtime = mtime;
2345 	}
2346 	sit_i->max_mtime = get_mtime(sbi);
2347 	mutex_unlock(&sit_i->sentry_lock);
2348 }
2349 
2350 int build_segment_manager(struct f2fs_sb_info *sbi)
2351 {
2352 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2353 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2354 	struct f2fs_sm_info *sm_info;
2355 	int err;
2356 
2357 	sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
2358 	if (!sm_info)
2359 		return -ENOMEM;
2360 
2361 	/* init sm info */
2362 	sbi->sm_info = sm_info;
2363 	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
2364 	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
2365 	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
2366 	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
2367 	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
2368 	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
2369 	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
2370 	sm_info->rec_prefree_segments = sm_info->main_segments *
2371 					DEF_RECLAIM_PREFREE_SEGMENTS / 100;
2372 	sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
2373 	sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
2374 	sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
2375 
2376 	INIT_LIST_HEAD(&sm_info->discard_list);
2377 	sm_info->nr_discards = 0;
2378 	sm_info->max_discards = 0;
2379 
2380 	sm_info->trim_sections = DEF_BATCHED_TRIM_SECTIONS;
2381 
2382 	INIT_LIST_HEAD(&sm_info->sit_entry_set);
2383 
2384 	if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) {
2385 		err = create_flush_cmd_control(sbi);
2386 		if (err)
2387 			return err;
2388 	}
2389 
2390 	err = build_sit_info(sbi);
2391 	if (err)
2392 		return err;
2393 	err = build_free_segmap(sbi);
2394 	if (err)
2395 		return err;
2396 	err = build_curseg(sbi);
2397 	if (err)
2398 		return err;
2399 
2400 	/* reinit free segmap based on SIT */
2401 	build_sit_entries(sbi);
2402 
2403 	init_free_segmap(sbi);
2404 	err = build_dirty_segmap(sbi);
2405 	if (err)
2406 		return err;
2407 
2408 	init_min_max_mtime(sbi);
2409 	return 0;
2410 }
2411 
2412 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
2413 		enum dirty_type dirty_type)
2414 {
2415 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2416 
2417 	mutex_lock(&dirty_i->seglist_lock);
2418 	kvfree(dirty_i->dirty_segmap[dirty_type]);
2419 	dirty_i->nr_dirty[dirty_type] = 0;
2420 	mutex_unlock(&dirty_i->seglist_lock);
2421 }
2422 
2423 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
2424 {
2425 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2426 	kvfree(dirty_i->victim_secmap);
2427 }
2428 
2429 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
2430 {
2431 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2432 	int i;
2433 
2434 	if (!dirty_i)
2435 		return;
2436 
2437 	/* discard pre-free/dirty segments list */
2438 	for (i = 0; i < NR_DIRTY_TYPE; i++)
2439 		discard_dirty_segmap(sbi, i);
2440 
2441 	destroy_victim_secmap(sbi);
2442 	SM_I(sbi)->dirty_info = NULL;
2443 	kfree(dirty_i);
2444 }
2445 
2446 static void destroy_curseg(struct f2fs_sb_info *sbi)
2447 {
2448 	struct curseg_info *array = SM_I(sbi)->curseg_array;
2449 	int i;
2450 
2451 	if (!array)
2452 		return;
2453 	SM_I(sbi)->curseg_array = NULL;
2454 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
2455 		kfree(array[i].sum_blk);
2456 		kfree(array[i].journal);
2457 	}
2458 	kfree(array);
2459 }
2460 
2461 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
2462 {
2463 	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
2464 	if (!free_i)
2465 		return;
2466 	SM_I(sbi)->free_info = NULL;
2467 	kvfree(free_i->free_segmap);
2468 	kvfree(free_i->free_secmap);
2469 	kfree(free_i);
2470 }
2471 
2472 static void destroy_sit_info(struct f2fs_sb_info *sbi)
2473 {
2474 	struct sit_info *sit_i = SIT_I(sbi);
2475 	unsigned int start;
2476 
2477 	if (!sit_i)
2478 		return;
2479 
2480 	if (sit_i->sentries) {
2481 		for (start = 0; start < MAIN_SEGS(sbi); start++) {
2482 			kfree(sit_i->sentries[start].cur_valid_map);
2483 			kfree(sit_i->sentries[start].ckpt_valid_map);
2484 			kfree(sit_i->sentries[start].discard_map);
2485 		}
2486 	}
2487 	kfree(sit_i->tmp_map);
2488 
2489 	kvfree(sit_i->sentries);
2490 	kvfree(sit_i->sec_entries);
2491 	kvfree(sit_i->dirty_sentries_bitmap);
2492 
2493 	SM_I(sbi)->sit_info = NULL;
2494 	kfree(sit_i->sit_bitmap);
2495 	kfree(sit_i);
2496 }
2497 
2498 void destroy_segment_manager(struct f2fs_sb_info *sbi)
2499 {
2500 	struct f2fs_sm_info *sm_info = SM_I(sbi);
2501 
2502 	if (!sm_info)
2503 		return;
2504 	destroy_flush_cmd_control(sbi);
2505 	destroy_dirty_segmap(sbi);
2506 	destroy_curseg(sbi);
2507 	destroy_free_segmap(sbi);
2508 	destroy_sit_info(sbi);
2509 	sbi->sm_info = NULL;
2510 	kfree(sm_info);
2511 }
2512 
2513 int __init create_segment_manager_caches(void)
2514 {
2515 	discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
2516 			sizeof(struct discard_entry));
2517 	if (!discard_entry_slab)
2518 		goto fail;
2519 
2520 	sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
2521 			sizeof(struct sit_entry_set));
2522 	if (!sit_entry_set_slab)
2523 		goto destory_discard_entry;
2524 
2525 	inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
2526 			sizeof(struct inmem_pages));
2527 	if (!inmem_entry_slab)
2528 		goto destroy_sit_entry_set;
2529 	return 0;
2530 
2531 destroy_sit_entry_set:
2532 	kmem_cache_destroy(sit_entry_set_slab);
2533 destory_discard_entry:
2534 	kmem_cache_destroy(discard_entry_slab);
2535 fail:
2536 	return -ENOMEM;
2537 }
2538 
2539 void destroy_segment_manager_caches(void)
2540 {
2541 	kmem_cache_destroy(sit_entry_set_slab);
2542 	kmem_cache_destroy(discard_entry_slab);
2543 	kmem_cache_destroy(inmem_entry_slab);
2544 }
2545