xref: /openbmc/linux/fs/f2fs/segment.c (revision a468f0ef516fda9c7d91bb550d458e853d76955e)
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 *bio_entry_slab;
30 static struct kmem_cache *sit_entry_set_slab;
31 static struct kmem_cache *inmem_entry_slab;
32 
33 static unsigned long __reverse_ulong(unsigned char *str)
34 {
35 	unsigned long tmp = 0;
36 	int shift = 24, idx = 0;
37 
38 #if BITS_PER_LONG == 64
39 	shift = 56;
40 #endif
41 	while (shift >= 0) {
42 		tmp |= (unsigned long)str[idx++] << shift;
43 		shift -= BITS_PER_BYTE;
44 	}
45 	return tmp;
46 }
47 
48 /*
49  * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
50  * MSB and LSB are reversed in a byte by f2fs_set_bit.
51  */
52 static inline unsigned long __reverse_ffs(unsigned long word)
53 {
54 	int num = 0;
55 
56 #if BITS_PER_LONG == 64
57 	if ((word & 0xffffffff00000000UL) == 0)
58 		num += 32;
59 	else
60 		word >>= 32;
61 #endif
62 	if ((word & 0xffff0000) == 0)
63 		num += 16;
64 	else
65 		word >>= 16;
66 
67 	if ((word & 0xff00) == 0)
68 		num += 8;
69 	else
70 		word >>= 8;
71 
72 	if ((word & 0xf0) == 0)
73 		num += 4;
74 	else
75 		word >>= 4;
76 
77 	if ((word & 0xc) == 0)
78 		num += 2;
79 	else
80 		word >>= 2;
81 
82 	if ((word & 0x2) == 0)
83 		num += 1;
84 	return num;
85 }
86 
87 /*
88  * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because
89  * f2fs_set_bit makes MSB and LSB reversed in a byte.
90  * @size must be integral times of unsigned long.
91  * Example:
92  *                             MSB <--> LSB
93  *   f2fs_set_bit(0, bitmap) => 1000 0000
94  *   f2fs_set_bit(7, bitmap) => 0000 0001
95  */
96 static unsigned long __find_rev_next_bit(const unsigned long *addr,
97 			unsigned long size, unsigned long offset)
98 {
99 	const unsigned long *p = addr + BIT_WORD(offset);
100 	unsigned long result = size;
101 	unsigned long tmp;
102 
103 	if (offset >= size)
104 		return size;
105 
106 	size -= (offset & ~(BITS_PER_LONG - 1));
107 	offset %= BITS_PER_LONG;
108 
109 	while (1) {
110 		if (*p == 0)
111 			goto pass;
112 
113 		tmp = __reverse_ulong((unsigned char *)p);
114 
115 		tmp &= ~0UL >> offset;
116 		if (size < BITS_PER_LONG)
117 			tmp &= (~0UL << (BITS_PER_LONG - size));
118 		if (tmp)
119 			goto found;
120 pass:
121 		if (size <= BITS_PER_LONG)
122 			break;
123 		size -= BITS_PER_LONG;
124 		offset = 0;
125 		p++;
126 	}
127 	return result;
128 found:
129 	return result - size + __reverse_ffs(tmp);
130 }
131 
132 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
133 			unsigned long size, unsigned long offset)
134 {
135 	const unsigned long *p = addr + BIT_WORD(offset);
136 	unsigned long result = size;
137 	unsigned long tmp;
138 
139 	if (offset >= size)
140 		return size;
141 
142 	size -= (offset & ~(BITS_PER_LONG - 1));
143 	offset %= BITS_PER_LONG;
144 
145 	while (1) {
146 		if (*p == ~0UL)
147 			goto pass;
148 
149 		tmp = __reverse_ulong((unsigned char *)p);
150 
151 		if (offset)
152 			tmp |= ~0UL << (BITS_PER_LONG - offset);
153 		if (size < BITS_PER_LONG)
154 			tmp |= ~0UL >> size;
155 		if (tmp != ~0UL)
156 			goto found;
157 pass:
158 		if (size <= BITS_PER_LONG)
159 			break;
160 		size -= BITS_PER_LONG;
161 		offset = 0;
162 		p++;
163 	}
164 	return result;
165 found:
166 	return result - size + __reverse_ffz(tmp);
167 }
168 
169 void register_inmem_page(struct inode *inode, struct page *page)
170 {
171 	struct f2fs_inode_info *fi = F2FS_I(inode);
172 	struct inmem_pages *new;
173 
174 	f2fs_trace_pid(page);
175 
176 	set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE);
177 	SetPagePrivate(page);
178 
179 	new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
180 
181 	/* add atomic page indices to the list */
182 	new->page = page;
183 	INIT_LIST_HEAD(&new->list);
184 
185 	/* increase reference count with clean state */
186 	mutex_lock(&fi->inmem_lock);
187 	get_page(page);
188 	list_add_tail(&new->list, &fi->inmem_pages);
189 	inc_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
190 	mutex_unlock(&fi->inmem_lock);
191 
192 	trace_f2fs_register_inmem_page(page, INMEM);
193 }
194 
195 static int __revoke_inmem_pages(struct inode *inode,
196 				struct list_head *head, bool drop, bool recover)
197 {
198 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
199 	struct inmem_pages *cur, *tmp;
200 	int err = 0;
201 
202 	list_for_each_entry_safe(cur, tmp, head, list) {
203 		struct page *page = cur->page;
204 
205 		if (drop)
206 			trace_f2fs_commit_inmem_page(page, INMEM_DROP);
207 
208 		lock_page(page);
209 
210 		if (recover) {
211 			struct dnode_of_data dn;
212 			struct node_info ni;
213 
214 			trace_f2fs_commit_inmem_page(page, INMEM_REVOKE);
215 
216 			set_new_dnode(&dn, inode, NULL, NULL, 0);
217 			if (get_dnode_of_data(&dn, page->index, LOOKUP_NODE)) {
218 				err = -EAGAIN;
219 				goto next;
220 			}
221 			get_node_info(sbi, dn.nid, &ni);
222 			f2fs_replace_block(sbi, &dn, dn.data_blkaddr,
223 					cur->old_addr, ni.version, true, true);
224 			f2fs_put_dnode(&dn);
225 		}
226 next:
227 		/* we don't need to invalidate this in the sccessful status */
228 		if (drop || recover)
229 			ClearPageUptodate(page);
230 		set_page_private(page, 0);
231 		ClearPagePrivate(page);
232 		f2fs_put_page(page, 1);
233 
234 		list_del(&cur->list);
235 		kmem_cache_free(inmem_entry_slab, cur);
236 		dec_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
237 	}
238 	return err;
239 }
240 
241 void drop_inmem_pages(struct inode *inode)
242 {
243 	struct f2fs_inode_info *fi = F2FS_I(inode);
244 
245 	clear_inode_flag(inode, FI_ATOMIC_FILE);
246 
247 	mutex_lock(&fi->inmem_lock);
248 	__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
249 	mutex_unlock(&fi->inmem_lock);
250 }
251 
252 static int __commit_inmem_pages(struct inode *inode,
253 					struct list_head *revoke_list)
254 {
255 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
256 	struct f2fs_inode_info *fi = F2FS_I(inode);
257 	struct inmem_pages *cur, *tmp;
258 	struct f2fs_io_info fio = {
259 		.sbi = sbi,
260 		.type = DATA,
261 		.op = REQ_OP_WRITE,
262 		.op_flags = WRITE_SYNC | REQ_PRIO,
263 		.encrypted_page = NULL,
264 	};
265 	bool submit_bio = false;
266 	int err = 0;
267 
268 	list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
269 		struct page *page = cur->page;
270 
271 		lock_page(page);
272 		if (page->mapping == inode->i_mapping) {
273 			trace_f2fs_commit_inmem_page(page, INMEM);
274 
275 			set_page_dirty(page);
276 			f2fs_wait_on_page_writeback(page, DATA, true);
277 			if (clear_page_dirty_for_io(page))
278 				inode_dec_dirty_pages(inode);
279 
280 			fio.page = page;
281 			err = do_write_data_page(&fio);
282 			if (err) {
283 				unlock_page(page);
284 				break;
285 			}
286 
287 			/* record old blkaddr for revoking */
288 			cur->old_addr = fio.old_blkaddr;
289 
290 			clear_cold_data(page);
291 			submit_bio = true;
292 		}
293 		unlock_page(page);
294 		list_move_tail(&cur->list, revoke_list);
295 	}
296 
297 	if (submit_bio)
298 		f2fs_submit_merged_bio_cond(sbi, inode, NULL, 0, DATA, WRITE);
299 
300 	if (!err)
301 		__revoke_inmem_pages(inode, revoke_list, false, false);
302 
303 	return err;
304 }
305 
306 int commit_inmem_pages(struct inode *inode)
307 {
308 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
309 	struct f2fs_inode_info *fi = F2FS_I(inode);
310 	struct list_head revoke_list;
311 	int err;
312 
313 	INIT_LIST_HEAD(&revoke_list);
314 	f2fs_balance_fs(sbi, true);
315 	f2fs_lock_op(sbi);
316 
317 	mutex_lock(&fi->inmem_lock);
318 	err = __commit_inmem_pages(inode, &revoke_list);
319 	if (err) {
320 		int ret;
321 		/*
322 		 * try to revoke all committed pages, but still we could fail
323 		 * due to no memory or other reason, if that happened, EAGAIN
324 		 * will be returned, which means in such case, transaction is
325 		 * already not integrity, caller should use journal to do the
326 		 * recovery or rewrite & commit last transaction. For other
327 		 * error number, revoking was done by filesystem itself.
328 		 */
329 		ret = __revoke_inmem_pages(inode, &revoke_list, false, true);
330 		if (ret)
331 			err = ret;
332 
333 		/* drop all uncommitted pages */
334 		__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
335 	}
336 	mutex_unlock(&fi->inmem_lock);
337 
338 	f2fs_unlock_op(sbi);
339 	return err;
340 }
341 
342 /*
343  * This function balances dirty node and dentry pages.
344  * In addition, it controls garbage collection.
345  */
346 void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
347 {
348 	if (!need)
349 		return;
350 
351 	/* balance_fs_bg is able to be pending */
352 	if (excess_cached_nats(sbi))
353 		f2fs_balance_fs_bg(sbi);
354 
355 	/*
356 	 * We should do GC or end up with checkpoint, if there are so many dirty
357 	 * dir/node pages without enough free segments.
358 	 */
359 	if (has_not_enough_free_secs(sbi, 0, 0)) {
360 		mutex_lock(&sbi->gc_mutex);
361 		f2fs_gc(sbi, false);
362 	}
363 }
364 
365 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
366 {
367 	/* try to shrink extent cache when there is no enough memory */
368 	if (!available_free_memory(sbi, EXTENT_CACHE))
369 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
370 
371 	/* check the # of cached NAT entries */
372 	if (!available_free_memory(sbi, NAT_ENTRIES))
373 		try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
374 
375 	if (!available_free_memory(sbi, FREE_NIDS))
376 		try_to_free_nids(sbi, MAX_FREE_NIDS);
377 	else
378 		build_free_nids(sbi);
379 
380 	/* checkpoint is the only way to shrink partial cached entries */
381 	if (!available_free_memory(sbi, NAT_ENTRIES) ||
382 			!available_free_memory(sbi, INO_ENTRIES) ||
383 			excess_prefree_segs(sbi) ||
384 			excess_dirty_nats(sbi) ||
385 			(is_idle(sbi) && f2fs_time_over(sbi, CP_TIME))) {
386 		if (test_opt(sbi, DATA_FLUSH)) {
387 			struct blk_plug plug;
388 
389 			blk_start_plug(&plug);
390 			sync_dirty_inodes(sbi, FILE_INODE);
391 			blk_finish_plug(&plug);
392 		}
393 		f2fs_sync_fs(sbi->sb, true);
394 		stat_inc_bg_cp_count(sbi->stat_info);
395 	}
396 }
397 
398 static int issue_flush_thread(void *data)
399 {
400 	struct f2fs_sb_info *sbi = data;
401 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
402 	wait_queue_head_t *q = &fcc->flush_wait_queue;
403 repeat:
404 	if (kthread_should_stop())
405 		return 0;
406 
407 	if (!llist_empty(&fcc->issue_list)) {
408 		struct bio *bio;
409 		struct flush_cmd *cmd, *next;
410 		int ret;
411 
412 		bio = f2fs_bio_alloc(0);
413 
414 		fcc->dispatch_list = llist_del_all(&fcc->issue_list);
415 		fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
416 
417 		bio->bi_bdev = sbi->sb->s_bdev;
418 		bio_set_op_attrs(bio, REQ_OP_WRITE, WRITE_FLUSH);
419 		ret = submit_bio_wait(bio);
420 
421 		llist_for_each_entry_safe(cmd, next,
422 					  fcc->dispatch_list, llnode) {
423 			cmd->ret = ret;
424 			complete(&cmd->wait);
425 		}
426 		bio_put(bio);
427 		fcc->dispatch_list = NULL;
428 	}
429 
430 	wait_event_interruptible(*q,
431 		kthread_should_stop() || !llist_empty(&fcc->issue_list));
432 	goto repeat;
433 }
434 
435 int f2fs_issue_flush(struct f2fs_sb_info *sbi)
436 {
437 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
438 	struct flush_cmd cmd;
439 
440 	trace_f2fs_issue_flush(sbi->sb, test_opt(sbi, NOBARRIER),
441 					test_opt(sbi, FLUSH_MERGE));
442 
443 	if (test_opt(sbi, NOBARRIER))
444 		return 0;
445 
446 	if (!test_opt(sbi, FLUSH_MERGE) || !atomic_read(&fcc->submit_flush)) {
447 		struct bio *bio = f2fs_bio_alloc(0);
448 		int ret;
449 
450 		atomic_inc(&fcc->submit_flush);
451 		bio->bi_bdev = sbi->sb->s_bdev;
452 		bio_set_op_attrs(bio, REQ_OP_WRITE, WRITE_FLUSH);
453 		ret = submit_bio_wait(bio);
454 		atomic_dec(&fcc->submit_flush);
455 		bio_put(bio);
456 		return ret;
457 	}
458 
459 	init_completion(&cmd.wait);
460 
461 	atomic_inc(&fcc->submit_flush);
462 	llist_add(&cmd.llnode, &fcc->issue_list);
463 
464 	if (!fcc->dispatch_list)
465 		wake_up(&fcc->flush_wait_queue);
466 
467 	wait_for_completion(&cmd.wait);
468 	atomic_dec(&fcc->submit_flush);
469 
470 	return cmd.ret;
471 }
472 
473 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
474 {
475 	dev_t dev = sbi->sb->s_bdev->bd_dev;
476 	struct flush_cmd_control *fcc;
477 	int err = 0;
478 
479 	fcc = kzalloc(sizeof(struct flush_cmd_control), GFP_KERNEL);
480 	if (!fcc)
481 		return -ENOMEM;
482 	atomic_set(&fcc->submit_flush, 0);
483 	init_waitqueue_head(&fcc->flush_wait_queue);
484 	init_llist_head(&fcc->issue_list);
485 	SM_I(sbi)->cmd_control_info = fcc;
486 	fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
487 				"f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
488 	if (IS_ERR(fcc->f2fs_issue_flush)) {
489 		err = PTR_ERR(fcc->f2fs_issue_flush);
490 		kfree(fcc);
491 		SM_I(sbi)->cmd_control_info = NULL;
492 		return err;
493 	}
494 
495 	return err;
496 }
497 
498 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi)
499 {
500 	struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
501 
502 	if (fcc && fcc->f2fs_issue_flush)
503 		kthread_stop(fcc->f2fs_issue_flush);
504 	kfree(fcc);
505 	SM_I(sbi)->cmd_control_info = NULL;
506 }
507 
508 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
509 		enum dirty_type dirty_type)
510 {
511 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
512 
513 	/* need not be added */
514 	if (IS_CURSEG(sbi, segno))
515 		return;
516 
517 	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
518 		dirty_i->nr_dirty[dirty_type]++;
519 
520 	if (dirty_type == DIRTY) {
521 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
522 		enum dirty_type t = sentry->type;
523 
524 		if (unlikely(t >= DIRTY)) {
525 			f2fs_bug_on(sbi, 1);
526 			return;
527 		}
528 		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
529 			dirty_i->nr_dirty[t]++;
530 	}
531 }
532 
533 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
534 		enum dirty_type dirty_type)
535 {
536 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
537 
538 	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
539 		dirty_i->nr_dirty[dirty_type]--;
540 
541 	if (dirty_type == DIRTY) {
542 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
543 		enum dirty_type t = sentry->type;
544 
545 		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
546 			dirty_i->nr_dirty[t]--;
547 
548 		if (get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0)
549 			clear_bit(GET_SECNO(sbi, segno),
550 						dirty_i->victim_secmap);
551 	}
552 }
553 
554 /*
555  * Should not occur error such as -ENOMEM.
556  * Adding dirty entry into seglist is not critical operation.
557  * If a given segment is one of current working segments, it won't be added.
558  */
559 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
560 {
561 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
562 	unsigned short valid_blocks;
563 
564 	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
565 		return;
566 
567 	mutex_lock(&dirty_i->seglist_lock);
568 
569 	valid_blocks = get_valid_blocks(sbi, segno, 0);
570 
571 	if (valid_blocks == 0) {
572 		__locate_dirty_segment(sbi, segno, PRE);
573 		__remove_dirty_segment(sbi, segno, DIRTY);
574 	} else if (valid_blocks < sbi->blocks_per_seg) {
575 		__locate_dirty_segment(sbi, segno, DIRTY);
576 	} else {
577 		/* Recovery routine with SSR needs this */
578 		__remove_dirty_segment(sbi, segno, DIRTY);
579 	}
580 
581 	mutex_unlock(&dirty_i->seglist_lock);
582 }
583 
584 static struct bio_entry *__add_bio_entry(struct f2fs_sb_info *sbi,
585 							struct bio *bio)
586 {
587 	struct list_head *wait_list = &(SM_I(sbi)->wait_list);
588 	struct bio_entry *be = f2fs_kmem_cache_alloc(bio_entry_slab, GFP_NOFS);
589 
590 	INIT_LIST_HEAD(&be->list);
591 	be->bio = bio;
592 	init_completion(&be->event);
593 	list_add_tail(&be->list, wait_list);
594 
595 	return be;
596 }
597 
598 void f2fs_wait_all_discard_bio(struct f2fs_sb_info *sbi)
599 {
600 	struct list_head *wait_list = &(SM_I(sbi)->wait_list);
601 	struct bio_entry *be, *tmp;
602 
603 	list_for_each_entry_safe(be, tmp, wait_list, list) {
604 		struct bio *bio = be->bio;
605 		int err;
606 
607 		wait_for_completion_io(&be->event);
608 		err = be->error;
609 		if (err == -EOPNOTSUPP)
610 			err = 0;
611 
612 		if (err)
613 			f2fs_msg(sbi->sb, KERN_INFO,
614 				"Issue discard failed, ret: %d", err);
615 
616 		bio_put(bio);
617 		list_del(&be->list);
618 		kmem_cache_free(bio_entry_slab, be);
619 	}
620 }
621 
622 static void f2fs_submit_bio_wait_endio(struct bio *bio)
623 {
624 	struct bio_entry *be = (struct bio_entry *)bio->bi_private;
625 
626 	be->error = bio->bi_error;
627 	complete(&be->event);
628 }
629 
630 /* this function is copied from blkdev_issue_discard from block/blk-lib.c */
631 int __f2fs_issue_discard_async(struct f2fs_sb_info *sbi, sector_t sector,
632 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
633 {
634 	struct block_device *bdev = sbi->sb->s_bdev;
635 	struct bio *bio = NULL;
636 	int err;
637 
638 	err = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, flags,
639 			&bio);
640 	if (!err && bio) {
641 		struct bio_entry *be = __add_bio_entry(sbi, bio);
642 
643 		bio->bi_private = be;
644 		bio->bi_end_io = f2fs_submit_bio_wait_endio;
645 		bio->bi_opf |= REQ_SYNC;
646 		submit_bio(bio);
647 	}
648 
649 	return err;
650 }
651 
652 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
653 				block_t blkstart, block_t blklen)
654 {
655 	sector_t start = SECTOR_FROM_BLOCK(blkstart);
656 	sector_t len = SECTOR_FROM_BLOCK(blklen);
657 	struct seg_entry *se;
658 	unsigned int offset;
659 	block_t i;
660 
661 	for (i = blkstart; i < blkstart + blklen; i++) {
662 		se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
663 		offset = GET_BLKOFF_FROM_SEG0(sbi, i);
664 
665 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
666 			sbi->discard_blks--;
667 	}
668 	trace_f2fs_issue_discard(sbi->sb, blkstart, blklen);
669 	return __f2fs_issue_discard_async(sbi, start, len, GFP_NOFS, 0);
670 }
671 
672 static void __add_discard_entry(struct f2fs_sb_info *sbi,
673 		struct cp_control *cpc, struct seg_entry *se,
674 		unsigned int start, unsigned int end)
675 {
676 	struct list_head *head = &SM_I(sbi)->discard_list;
677 	struct discard_entry *new, *last;
678 
679 	if (!list_empty(head)) {
680 		last = list_last_entry(head, struct discard_entry, list);
681 		if (START_BLOCK(sbi, cpc->trim_start) + start ==
682 						last->blkaddr + last->len) {
683 			last->len += end - start;
684 			goto done;
685 		}
686 	}
687 
688 	new = f2fs_kmem_cache_alloc(discard_entry_slab, GFP_NOFS);
689 	INIT_LIST_HEAD(&new->list);
690 	new->blkaddr = START_BLOCK(sbi, cpc->trim_start) + start;
691 	new->len = end - start;
692 	list_add_tail(&new->list, head);
693 done:
694 	SM_I(sbi)->nr_discards += end - start;
695 }
696 
697 static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
698 {
699 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
700 	int max_blocks = sbi->blocks_per_seg;
701 	struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
702 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
703 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
704 	unsigned long *discard_map = (unsigned long *)se->discard_map;
705 	unsigned long *dmap = SIT_I(sbi)->tmp_map;
706 	unsigned int start = 0, end = -1;
707 	bool force = (cpc->reason == CP_DISCARD);
708 	int i;
709 
710 	if (se->valid_blocks == max_blocks || !f2fs_discard_en(sbi))
711 		return;
712 
713 	if (!force) {
714 		if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
715 		    SM_I(sbi)->nr_discards >= SM_I(sbi)->max_discards)
716 			return;
717 	}
718 
719 	/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
720 	for (i = 0; i < entries; i++)
721 		dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
722 				(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
723 
724 	while (force || SM_I(sbi)->nr_discards <= SM_I(sbi)->max_discards) {
725 		start = __find_rev_next_bit(dmap, max_blocks, end + 1);
726 		if (start >= max_blocks)
727 			break;
728 
729 		end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
730 		if (force && start && end != max_blocks
731 					&& (end - start) < cpc->trim_minlen)
732 			continue;
733 
734 		__add_discard_entry(sbi, cpc, se, start, end);
735 	}
736 }
737 
738 void release_discard_addrs(struct f2fs_sb_info *sbi)
739 {
740 	struct list_head *head = &(SM_I(sbi)->discard_list);
741 	struct discard_entry *entry, *this;
742 
743 	/* drop caches */
744 	list_for_each_entry_safe(entry, this, head, list) {
745 		list_del(&entry->list);
746 		kmem_cache_free(discard_entry_slab, entry);
747 	}
748 }
749 
750 /*
751  * Should call clear_prefree_segments after checkpoint is done.
752  */
753 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
754 {
755 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
756 	unsigned int segno;
757 
758 	mutex_lock(&dirty_i->seglist_lock);
759 	for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
760 		__set_test_and_free(sbi, segno);
761 	mutex_unlock(&dirty_i->seglist_lock);
762 }
763 
764 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
765 {
766 	struct list_head *head = &(SM_I(sbi)->discard_list);
767 	struct discard_entry *entry, *this;
768 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
769 	struct blk_plug plug;
770 	unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
771 	unsigned int start = 0, end = -1;
772 	unsigned int secno, start_segno;
773 	bool force = (cpc->reason == CP_DISCARD);
774 
775 	blk_start_plug(&plug);
776 
777 	mutex_lock(&dirty_i->seglist_lock);
778 
779 	while (1) {
780 		int i;
781 		start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
782 		if (start >= MAIN_SEGS(sbi))
783 			break;
784 		end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
785 								start + 1);
786 
787 		for (i = start; i < end; i++)
788 			clear_bit(i, prefree_map);
789 
790 		dirty_i->nr_dirty[PRE] -= end - start;
791 
792 		if (force || !test_opt(sbi, DISCARD))
793 			continue;
794 
795 		if (!test_opt(sbi, LFS) || sbi->segs_per_sec == 1) {
796 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
797 				(end - start) << sbi->log_blocks_per_seg);
798 			continue;
799 		}
800 next:
801 		secno = GET_SECNO(sbi, start);
802 		start_segno = secno * sbi->segs_per_sec;
803 		if (!IS_CURSEC(sbi, secno) &&
804 			!get_valid_blocks(sbi, start, sbi->segs_per_sec))
805 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start_segno),
806 				sbi->segs_per_sec << sbi->log_blocks_per_seg);
807 
808 		start = start_segno + sbi->segs_per_sec;
809 		if (start < end)
810 			goto next;
811 	}
812 	mutex_unlock(&dirty_i->seglist_lock);
813 
814 	/* send small discards */
815 	list_for_each_entry_safe(entry, this, head, list) {
816 		if (force && entry->len < cpc->trim_minlen)
817 			goto skip;
818 		f2fs_issue_discard(sbi, entry->blkaddr, entry->len);
819 		cpc->trimmed += entry->len;
820 skip:
821 		list_del(&entry->list);
822 		SM_I(sbi)->nr_discards -= entry->len;
823 		kmem_cache_free(discard_entry_slab, entry);
824 	}
825 
826 	blk_finish_plug(&plug);
827 }
828 
829 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
830 {
831 	struct sit_info *sit_i = SIT_I(sbi);
832 
833 	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
834 		sit_i->dirty_sentries++;
835 		return false;
836 	}
837 
838 	return true;
839 }
840 
841 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
842 					unsigned int segno, int modified)
843 {
844 	struct seg_entry *se = get_seg_entry(sbi, segno);
845 	se->type = type;
846 	if (modified)
847 		__mark_sit_entry_dirty(sbi, segno);
848 }
849 
850 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
851 {
852 	struct seg_entry *se;
853 	unsigned int segno, offset;
854 	long int new_vblocks;
855 
856 	segno = GET_SEGNO(sbi, blkaddr);
857 
858 	se = get_seg_entry(sbi, segno);
859 	new_vblocks = se->valid_blocks + del;
860 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
861 
862 	f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
863 				(new_vblocks > sbi->blocks_per_seg)));
864 
865 	se->valid_blocks = new_vblocks;
866 	se->mtime = get_mtime(sbi);
867 	SIT_I(sbi)->max_mtime = se->mtime;
868 
869 	/* Update valid block bitmap */
870 	if (del > 0) {
871 		if (f2fs_test_and_set_bit(offset, se->cur_valid_map))
872 			f2fs_bug_on(sbi, 1);
873 		if (f2fs_discard_en(sbi) &&
874 			!f2fs_test_and_set_bit(offset, se->discard_map))
875 			sbi->discard_blks--;
876 	} else {
877 		if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map))
878 			f2fs_bug_on(sbi, 1);
879 		if (f2fs_discard_en(sbi) &&
880 			f2fs_test_and_clear_bit(offset, se->discard_map))
881 			sbi->discard_blks++;
882 	}
883 	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
884 		se->ckpt_valid_blocks += del;
885 
886 	__mark_sit_entry_dirty(sbi, segno);
887 
888 	/* update total number of valid blocks to be written in ckpt area */
889 	SIT_I(sbi)->written_valid_blocks += del;
890 
891 	if (sbi->segs_per_sec > 1)
892 		get_sec_entry(sbi, segno)->valid_blocks += del;
893 }
894 
895 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new)
896 {
897 	update_sit_entry(sbi, new, 1);
898 	if (GET_SEGNO(sbi, old) != NULL_SEGNO)
899 		update_sit_entry(sbi, old, -1);
900 
901 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old));
902 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new));
903 }
904 
905 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
906 {
907 	unsigned int segno = GET_SEGNO(sbi, addr);
908 	struct sit_info *sit_i = SIT_I(sbi);
909 
910 	f2fs_bug_on(sbi, addr == NULL_ADDR);
911 	if (addr == NEW_ADDR)
912 		return;
913 
914 	/* add it into sit main buffer */
915 	mutex_lock(&sit_i->sentry_lock);
916 
917 	update_sit_entry(sbi, addr, -1);
918 
919 	/* add it into dirty seglist */
920 	locate_dirty_segment(sbi, segno);
921 
922 	mutex_unlock(&sit_i->sentry_lock);
923 }
924 
925 bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
926 {
927 	struct sit_info *sit_i = SIT_I(sbi);
928 	unsigned int segno, offset;
929 	struct seg_entry *se;
930 	bool is_cp = false;
931 
932 	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR)
933 		return true;
934 
935 	mutex_lock(&sit_i->sentry_lock);
936 
937 	segno = GET_SEGNO(sbi, blkaddr);
938 	se = get_seg_entry(sbi, segno);
939 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
940 
941 	if (f2fs_test_bit(offset, se->ckpt_valid_map))
942 		is_cp = true;
943 
944 	mutex_unlock(&sit_i->sentry_lock);
945 
946 	return is_cp;
947 }
948 
949 /*
950  * This function should be resided under the curseg_mutex lock
951  */
952 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
953 					struct f2fs_summary *sum)
954 {
955 	struct curseg_info *curseg = CURSEG_I(sbi, type);
956 	void *addr = curseg->sum_blk;
957 	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
958 	memcpy(addr, sum, sizeof(struct f2fs_summary));
959 }
960 
961 /*
962  * Calculate the number of current summary pages for writing
963  */
964 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
965 {
966 	int valid_sum_count = 0;
967 	int i, sum_in_page;
968 
969 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
970 		if (sbi->ckpt->alloc_type[i] == SSR)
971 			valid_sum_count += sbi->blocks_per_seg;
972 		else {
973 			if (for_ra)
974 				valid_sum_count += le16_to_cpu(
975 					F2FS_CKPT(sbi)->cur_data_blkoff[i]);
976 			else
977 				valid_sum_count += curseg_blkoff(sbi, i);
978 		}
979 	}
980 
981 	sum_in_page = (PAGE_SIZE - 2 * SUM_JOURNAL_SIZE -
982 			SUM_FOOTER_SIZE) / SUMMARY_SIZE;
983 	if (valid_sum_count <= sum_in_page)
984 		return 1;
985 	else if ((valid_sum_count - sum_in_page) <=
986 		(PAGE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
987 		return 2;
988 	return 3;
989 }
990 
991 /*
992  * Caller should put this summary page
993  */
994 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
995 {
996 	return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
997 }
998 
999 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr)
1000 {
1001 	struct page *page = grab_meta_page(sbi, blk_addr);
1002 	void *dst = page_address(page);
1003 
1004 	if (src)
1005 		memcpy(dst, src, PAGE_SIZE);
1006 	else
1007 		memset(dst, 0, PAGE_SIZE);
1008 	set_page_dirty(page);
1009 	f2fs_put_page(page, 1);
1010 }
1011 
1012 static void write_sum_page(struct f2fs_sb_info *sbi,
1013 			struct f2fs_summary_block *sum_blk, block_t blk_addr)
1014 {
1015 	update_meta_page(sbi, (void *)sum_blk, blk_addr);
1016 }
1017 
1018 static void write_current_sum_page(struct f2fs_sb_info *sbi,
1019 						int type, block_t blk_addr)
1020 {
1021 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1022 	struct page *page = grab_meta_page(sbi, blk_addr);
1023 	struct f2fs_summary_block *src = curseg->sum_blk;
1024 	struct f2fs_summary_block *dst;
1025 
1026 	dst = (struct f2fs_summary_block *)page_address(page);
1027 
1028 	mutex_lock(&curseg->curseg_mutex);
1029 
1030 	down_read(&curseg->journal_rwsem);
1031 	memcpy(&dst->journal, curseg->journal, SUM_JOURNAL_SIZE);
1032 	up_read(&curseg->journal_rwsem);
1033 
1034 	memcpy(dst->entries, src->entries, SUM_ENTRY_SIZE);
1035 	memcpy(&dst->footer, &src->footer, SUM_FOOTER_SIZE);
1036 
1037 	mutex_unlock(&curseg->curseg_mutex);
1038 
1039 	set_page_dirty(page);
1040 	f2fs_put_page(page, 1);
1041 }
1042 
1043 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
1044 {
1045 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1046 	unsigned int segno = curseg->segno + 1;
1047 	struct free_segmap_info *free_i = FREE_I(sbi);
1048 
1049 	if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
1050 		return !test_bit(segno, free_i->free_segmap);
1051 	return 0;
1052 }
1053 
1054 /*
1055  * Find a new segment from the free segments bitmap to right order
1056  * This function should be returned with success, otherwise BUG
1057  */
1058 static void get_new_segment(struct f2fs_sb_info *sbi,
1059 			unsigned int *newseg, bool new_sec, int dir)
1060 {
1061 	struct free_segmap_info *free_i = FREE_I(sbi);
1062 	unsigned int segno, secno, zoneno;
1063 	unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
1064 	unsigned int hint = *newseg / sbi->segs_per_sec;
1065 	unsigned int old_zoneno = GET_ZONENO_FROM_SEGNO(sbi, *newseg);
1066 	unsigned int left_start = hint;
1067 	bool init = true;
1068 	int go_left = 0;
1069 	int i;
1070 
1071 	spin_lock(&free_i->segmap_lock);
1072 
1073 	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
1074 		segno = find_next_zero_bit(free_i->free_segmap,
1075 				(hint + 1) * sbi->segs_per_sec, *newseg + 1);
1076 		if (segno < (hint + 1) * sbi->segs_per_sec)
1077 			goto got_it;
1078 	}
1079 find_other_zone:
1080 	secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
1081 	if (secno >= MAIN_SECS(sbi)) {
1082 		if (dir == ALLOC_RIGHT) {
1083 			secno = find_next_zero_bit(free_i->free_secmap,
1084 							MAIN_SECS(sbi), 0);
1085 			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
1086 		} else {
1087 			go_left = 1;
1088 			left_start = hint - 1;
1089 		}
1090 	}
1091 	if (go_left == 0)
1092 		goto skip_left;
1093 
1094 	while (test_bit(left_start, free_i->free_secmap)) {
1095 		if (left_start > 0) {
1096 			left_start--;
1097 			continue;
1098 		}
1099 		left_start = find_next_zero_bit(free_i->free_secmap,
1100 							MAIN_SECS(sbi), 0);
1101 		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
1102 		break;
1103 	}
1104 	secno = left_start;
1105 skip_left:
1106 	hint = secno;
1107 	segno = secno * sbi->segs_per_sec;
1108 	zoneno = secno / sbi->secs_per_zone;
1109 
1110 	/* give up on finding another zone */
1111 	if (!init)
1112 		goto got_it;
1113 	if (sbi->secs_per_zone == 1)
1114 		goto got_it;
1115 	if (zoneno == old_zoneno)
1116 		goto got_it;
1117 	if (dir == ALLOC_LEFT) {
1118 		if (!go_left && zoneno + 1 >= total_zones)
1119 			goto got_it;
1120 		if (go_left && zoneno == 0)
1121 			goto got_it;
1122 	}
1123 	for (i = 0; i < NR_CURSEG_TYPE; i++)
1124 		if (CURSEG_I(sbi, i)->zone == zoneno)
1125 			break;
1126 
1127 	if (i < NR_CURSEG_TYPE) {
1128 		/* zone is in user, try another */
1129 		if (go_left)
1130 			hint = zoneno * sbi->secs_per_zone - 1;
1131 		else if (zoneno + 1 >= total_zones)
1132 			hint = 0;
1133 		else
1134 			hint = (zoneno + 1) * sbi->secs_per_zone;
1135 		init = false;
1136 		goto find_other_zone;
1137 	}
1138 got_it:
1139 	/* set it as dirty segment in free segmap */
1140 	f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
1141 	__set_inuse(sbi, segno);
1142 	*newseg = segno;
1143 	spin_unlock(&free_i->segmap_lock);
1144 }
1145 
1146 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
1147 {
1148 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1149 	struct summary_footer *sum_footer;
1150 
1151 	curseg->segno = curseg->next_segno;
1152 	curseg->zone = GET_ZONENO_FROM_SEGNO(sbi, curseg->segno);
1153 	curseg->next_blkoff = 0;
1154 	curseg->next_segno = NULL_SEGNO;
1155 
1156 	sum_footer = &(curseg->sum_blk->footer);
1157 	memset(sum_footer, 0, sizeof(struct summary_footer));
1158 	if (IS_DATASEG(type))
1159 		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
1160 	if (IS_NODESEG(type))
1161 		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
1162 	__set_sit_entry_type(sbi, type, curseg->segno, modified);
1163 }
1164 
1165 /*
1166  * Allocate a current working segment.
1167  * This function always allocates a free segment in LFS manner.
1168  */
1169 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
1170 {
1171 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1172 	unsigned int segno = curseg->segno;
1173 	int dir = ALLOC_LEFT;
1174 
1175 	write_sum_page(sbi, curseg->sum_blk,
1176 				GET_SUM_BLOCK(sbi, segno));
1177 	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
1178 		dir = ALLOC_RIGHT;
1179 
1180 	if (test_opt(sbi, NOHEAP))
1181 		dir = ALLOC_RIGHT;
1182 
1183 	get_new_segment(sbi, &segno, new_sec, dir);
1184 	curseg->next_segno = segno;
1185 	reset_curseg(sbi, type, 1);
1186 	curseg->alloc_type = LFS;
1187 }
1188 
1189 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
1190 			struct curseg_info *seg, block_t start)
1191 {
1192 	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
1193 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1194 	unsigned long *target_map = SIT_I(sbi)->tmp_map;
1195 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1196 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1197 	int i, pos;
1198 
1199 	for (i = 0; i < entries; i++)
1200 		target_map[i] = ckpt_map[i] | cur_map[i];
1201 
1202 	pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
1203 
1204 	seg->next_blkoff = pos;
1205 }
1206 
1207 /*
1208  * If a segment is written by LFS manner, next block offset is just obtained
1209  * by increasing the current block offset. However, if a segment is written by
1210  * SSR manner, next block offset obtained by calling __next_free_blkoff
1211  */
1212 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
1213 				struct curseg_info *seg)
1214 {
1215 	if (seg->alloc_type == SSR)
1216 		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
1217 	else
1218 		seg->next_blkoff++;
1219 }
1220 
1221 /*
1222  * This function always allocates a used segment(from dirty seglist) by SSR
1223  * manner, so it should recover the existing segment information of valid blocks
1224  */
1225 static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
1226 {
1227 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1228 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1229 	unsigned int new_segno = curseg->next_segno;
1230 	struct f2fs_summary_block *sum_node;
1231 	struct page *sum_page;
1232 
1233 	write_sum_page(sbi, curseg->sum_blk,
1234 				GET_SUM_BLOCK(sbi, curseg->segno));
1235 	__set_test_and_inuse(sbi, new_segno);
1236 
1237 	mutex_lock(&dirty_i->seglist_lock);
1238 	__remove_dirty_segment(sbi, new_segno, PRE);
1239 	__remove_dirty_segment(sbi, new_segno, DIRTY);
1240 	mutex_unlock(&dirty_i->seglist_lock);
1241 
1242 	reset_curseg(sbi, type, 1);
1243 	curseg->alloc_type = SSR;
1244 	__next_free_blkoff(sbi, curseg, 0);
1245 
1246 	if (reuse) {
1247 		sum_page = get_sum_page(sbi, new_segno);
1248 		sum_node = (struct f2fs_summary_block *)page_address(sum_page);
1249 		memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
1250 		f2fs_put_page(sum_page, 1);
1251 	}
1252 }
1253 
1254 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
1255 {
1256 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1257 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
1258 
1259 	if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0, 0))
1260 		return v_ops->get_victim(sbi,
1261 				&(curseg)->next_segno, BG_GC, type, SSR);
1262 
1263 	/* For data segments, let's do SSR more intensively */
1264 	for (; type >= CURSEG_HOT_DATA; type--)
1265 		if (v_ops->get_victim(sbi, &(curseg)->next_segno,
1266 						BG_GC, type, SSR))
1267 			return 1;
1268 	return 0;
1269 }
1270 
1271 /*
1272  * flush out current segment and replace it with new segment
1273  * This function should be returned with success, otherwise BUG
1274  */
1275 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
1276 						int type, bool force)
1277 {
1278 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1279 
1280 	if (force)
1281 		new_curseg(sbi, type, true);
1282 	else if (type == CURSEG_WARM_NODE)
1283 		new_curseg(sbi, type, false);
1284 	else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
1285 		new_curseg(sbi, type, false);
1286 	else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
1287 		change_curseg(sbi, type, true);
1288 	else
1289 		new_curseg(sbi, type, false);
1290 
1291 	stat_inc_seg_type(sbi, curseg);
1292 }
1293 
1294 static void __allocate_new_segments(struct f2fs_sb_info *sbi, int type)
1295 {
1296 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1297 	unsigned int old_segno;
1298 
1299 	old_segno = curseg->segno;
1300 	SIT_I(sbi)->s_ops->allocate_segment(sbi, type, true);
1301 	locate_dirty_segment(sbi, old_segno);
1302 }
1303 
1304 void allocate_new_segments(struct f2fs_sb_info *sbi)
1305 {
1306 	int i;
1307 
1308 	if (test_opt(sbi, LFS))
1309 		return;
1310 
1311 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)
1312 		__allocate_new_segments(sbi, i);
1313 }
1314 
1315 static const struct segment_allocation default_salloc_ops = {
1316 	.allocate_segment = allocate_segment_by_default,
1317 };
1318 
1319 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
1320 {
1321 	__u64 start = F2FS_BYTES_TO_BLK(range->start);
1322 	__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
1323 	unsigned int start_segno, end_segno;
1324 	struct cp_control cpc;
1325 	int err = 0;
1326 
1327 	if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
1328 		return -EINVAL;
1329 
1330 	cpc.trimmed = 0;
1331 	if (end <= MAIN_BLKADDR(sbi))
1332 		goto out;
1333 
1334 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
1335 		f2fs_msg(sbi->sb, KERN_WARNING,
1336 			"Found FS corruption, run fsck to fix.");
1337 		goto out;
1338 	}
1339 
1340 	/* start/end segment number in main_area */
1341 	start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
1342 	end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
1343 						GET_SEGNO(sbi, end);
1344 	cpc.reason = CP_DISCARD;
1345 	cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
1346 
1347 	/* do checkpoint to issue discard commands safely */
1348 	for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
1349 		cpc.trim_start = start_segno;
1350 
1351 		if (sbi->discard_blks == 0)
1352 			break;
1353 		else if (sbi->discard_blks < BATCHED_TRIM_BLOCKS(sbi))
1354 			cpc.trim_end = end_segno;
1355 		else
1356 			cpc.trim_end = min_t(unsigned int,
1357 				rounddown(start_segno +
1358 				BATCHED_TRIM_SEGMENTS(sbi),
1359 				sbi->segs_per_sec) - 1, end_segno);
1360 
1361 		mutex_lock(&sbi->gc_mutex);
1362 		err = write_checkpoint(sbi, &cpc);
1363 		mutex_unlock(&sbi->gc_mutex);
1364 		if (err)
1365 			break;
1366 
1367 		schedule();
1368 	}
1369 out:
1370 	range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
1371 	return err;
1372 }
1373 
1374 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
1375 {
1376 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1377 	if (curseg->next_blkoff < sbi->blocks_per_seg)
1378 		return true;
1379 	return false;
1380 }
1381 
1382 static int __get_segment_type_2(struct page *page, enum page_type p_type)
1383 {
1384 	if (p_type == DATA)
1385 		return CURSEG_HOT_DATA;
1386 	else
1387 		return CURSEG_HOT_NODE;
1388 }
1389 
1390 static int __get_segment_type_4(struct page *page, enum page_type p_type)
1391 {
1392 	if (p_type == DATA) {
1393 		struct inode *inode = page->mapping->host;
1394 
1395 		if (S_ISDIR(inode->i_mode))
1396 			return CURSEG_HOT_DATA;
1397 		else
1398 			return CURSEG_COLD_DATA;
1399 	} else {
1400 		if (IS_DNODE(page) && is_cold_node(page))
1401 			return CURSEG_WARM_NODE;
1402 		else
1403 			return CURSEG_COLD_NODE;
1404 	}
1405 }
1406 
1407 static int __get_segment_type_6(struct page *page, enum page_type p_type)
1408 {
1409 	if (p_type == DATA) {
1410 		struct inode *inode = page->mapping->host;
1411 
1412 		if (S_ISDIR(inode->i_mode))
1413 			return CURSEG_HOT_DATA;
1414 		else if (is_cold_data(page) || file_is_cold(inode))
1415 			return CURSEG_COLD_DATA;
1416 		else
1417 			return CURSEG_WARM_DATA;
1418 	} else {
1419 		if (IS_DNODE(page))
1420 			return is_cold_node(page) ? CURSEG_WARM_NODE :
1421 						CURSEG_HOT_NODE;
1422 		else
1423 			return CURSEG_COLD_NODE;
1424 	}
1425 }
1426 
1427 static int __get_segment_type(struct page *page, enum page_type p_type)
1428 {
1429 	switch (F2FS_P_SB(page)->active_logs) {
1430 	case 2:
1431 		return __get_segment_type_2(page, p_type);
1432 	case 4:
1433 		return __get_segment_type_4(page, p_type);
1434 	}
1435 	/* NR_CURSEG_TYPE(6) logs by default */
1436 	f2fs_bug_on(F2FS_P_SB(page),
1437 		F2FS_P_SB(page)->active_logs != NR_CURSEG_TYPE);
1438 	return __get_segment_type_6(page, p_type);
1439 }
1440 
1441 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
1442 		block_t old_blkaddr, block_t *new_blkaddr,
1443 		struct f2fs_summary *sum, int type)
1444 {
1445 	struct sit_info *sit_i = SIT_I(sbi);
1446 	struct curseg_info *curseg;
1447 	bool direct_io = (type == CURSEG_DIRECT_IO);
1448 
1449 	type = direct_io ? CURSEG_WARM_DATA : type;
1450 
1451 	curseg = CURSEG_I(sbi, type);
1452 
1453 	mutex_lock(&curseg->curseg_mutex);
1454 	mutex_lock(&sit_i->sentry_lock);
1455 
1456 	/* direct_io'ed data is aligned to the segment for better performance */
1457 	if (direct_io && curseg->next_blkoff &&
1458 				!has_not_enough_free_secs(sbi, 0, 0))
1459 		__allocate_new_segments(sbi, type);
1460 
1461 	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
1462 
1463 	/*
1464 	 * __add_sum_entry should be resided under the curseg_mutex
1465 	 * because, this function updates a summary entry in the
1466 	 * current summary block.
1467 	 */
1468 	__add_sum_entry(sbi, type, sum);
1469 
1470 	__refresh_next_blkoff(sbi, curseg);
1471 
1472 	stat_inc_block_count(sbi, curseg);
1473 
1474 	if (!__has_curseg_space(sbi, type))
1475 		sit_i->s_ops->allocate_segment(sbi, type, false);
1476 	/*
1477 	 * SIT information should be updated before segment allocation,
1478 	 * since SSR needs latest valid block information.
1479 	 */
1480 	refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
1481 
1482 	mutex_unlock(&sit_i->sentry_lock);
1483 
1484 	if (page && IS_NODESEG(type))
1485 		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
1486 
1487 	mutex_unlock(&curseg->curseg_mutex);
1488 }
1489 
1490 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
1491 {
1492 	int type = __get_segment_type(fio->page, fio->type);
1493 
1494 	if (fio->type == NODE || fio->type == DATA)
1495 		mutex_lock(&fio->sbi->wio_mutex[fio->type]);
1496 
1497 	allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
1498 					&fio->new_blkaddr, sum, type);
1499 
1500 	/* writeout dirty page into bdev */
1501 	f2fs_submit_page_mbio(fio);
1502 
1503 	if (fio->type == NODE || fio->type == DATA)
1504 		mutex_unlock(&fio->sbi->wio_mutex[fio->type]);
1505 }
1506 
1507 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
1508 {
1509 	struct f2fs_io_info fio = {
1510 		.sbi = sbi,
1511 		.type = META,
1512 		.op = REQ_OP_WRITE,
1513 		.op_flags = WRITE_SYNC | REQ_META | REQ_PRIO,
1514 		.old_blkaddr = page->index,
1515 		.new_blkaddr = page->index,
1516 		.page = page,
1517 		.encrypted_page = NULL,
1518 	};
1519 
1520 	if (unlikely(page->index >= MAIN_BLKADDR(sbi)))
1521 		fio.op_flags &= ~REQ_META;
1522 
1523 	set_page_writeback(page);
1524 	f2fs_submit_page_mbio(&fio);
1525 }
1526 
1527 void write_node_page(unsigned int nid, struct f2fs_io_info *fio)
1528 {
1529 	struct f2fs_summary sum;
1530 
1531 	set_summary(&sum, nid, 0, 0);
1532 	do_write_page(&sum, fio);
1533 }
1534 
1535 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio)
1536 {
1537 	struct f2fs_sb_info *sbi = fio->sbi;
1538 	struct f2fs_summary sum;
1539 	struct node_info ni;
1540 
1541 	f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
1542 	get_node_info(sbi, dn->nid, &ni);
1543 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
1544 	do_write_page(&sum, fio);
1545 	f2fs_update_data_blkaddr(dn, fio->new_blkaddr);
1546 }
1547 
1548 void rewrite_data_page(struct f2fs_io_info *fio)
1549 {
1550 	fio->new_blkaddr = fio->old_blkaddr;
1551 	stat_inc_inplace_blocks(fio->sbi);
1552 	f2fs_submit_page_mbio(fio);
1553 }
1554 
1555 void __f2fs_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
1556 				block_t old_blkaddr, block_t new_blkaddr,
1557 				bool recover_curseg, bool recover_newaddr)
1558 {
1559 	struct sit_info *sit_i = SIT_I(sbi);
1560 	struct curseg_info *curseg;
1561 	unsigned int segno, old_cursegno;
1562 	struct seg_entry *se;
1563 	int type;
1564 	unsigned short old_blkoff;
1565 
1566 	segno = GET_SEGNO(sbi, new_blkaddr);
1567 	se = get_seg_entry(sbi, segno);
1568 	type = se->type;
1569 
1570 	if (!recover_curseg) {
1571 		/* for recovery flow */
1572 		if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
1573 			if (old_blkaddr == NULL_ADDR)
1574 				type = CURSEG_COLD_DATA;
1575 			else
1576 				type = CURSEG_WARM_DATA;
1577 		}
1578 	} else {
1579 		if (!IS_CURSEG(sbi, segno))
1580 			type = CURSEG_WARM_DATA;
1581 	}
1582 
1583 	curseg = CURSEG_I(sbi, type);
1584 
1585 	mutex_lock(&curseg->curseg_mutex);
1586 	mutex_lock(&sit_i->sentry_lock);
1587 
1588 	old_cursegno = curseg->segno;
1589 	old_blkoff = curseg->next_blkoff;
1590 
1591 	/* change the current segment */
1592 	if (segno != curseg->segno) {
1593 		curseg->next_segno = segno;
1594 		change_curseg(sbi, type, true);
1595 	}
1596 
1597 	curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
1598 	__add_sum_entry(sbi, type, sum);
1599 
1600 	if (!recover_curseg || recover_newaddr)
1601 		update_sit_entry(sbi, new_blkaddr, 1);
1602 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
1603 		update_sit_entry(sbi, old_blkaddr, -1);
1604 
1605 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
1606 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new_blkaddr));
1607 
1608 	locate_dirty_segment(sbi, old_cursegno);
1609 
1610 	if (recover_curseg) {
1611 		if (old_cursegno != curseg->segno) {
1612 			curseg->next_segno = old_cursegno;
1613 			change_curseg(sbi, type, true);
1614 		}
1615 		curseg->next_blkoff = old_blkoff;
1616 	}
1617 
1618 	mutex_unlock(&sit_i->sentry_lock);
1619 	mutex_unlock(&curseg->curseg_mutex);
1620 }
1621 
1622 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
1623 				block_t old_addr, block_t new_addr,
1624 				unsigned char version, bool recover_curseg,
1625 				bool recover_newaddr)
1626 {
1627 	struct f2fs_summary sum;
1628 
1629 	set_summary(&sum, dn->nid, dn->ofs_in_node, version);
1630 
1631 	__f2fs_replace_block(sbi, &sum, old_addr, new_addr,
1632 					recover_curseg, recover_newaddr);
1633 
1634 	f2fs_update_data_blkaddr(dn, new_addr);
1635 }
1636 
1637 void f2fs_wait_on_page_writeback(struct page *page,
1638 				enum page_type type, bool ordered)
1639 {
1640 	if (PageWriteback(page)) {
1641 		struct f2fs_sb_info *sbi = F2FS_P_SB(page);
1642 
1643 		f2fs_submit_merged_bio_cond(sbi, NULL, page, 0, type, WRITE);
1644 		if (ordered)
1645 			wait_on_page_writeback(page);
1646 		else
1647 			wait_for_stable_page(page);
1648 	}
1649 }
1650 
1651 void f2fs_wait_on_encrypted_page_writeback(struct f2fs_sb_info *sbi,
1652 							block_t blkaddr)
1653 {
1654 	struct page *cpage;
1655 
1656 	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR)
1657 		return;
1658 
1659 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
1660 	if (cpage) {
1661 		f2fs_wait_on_page_writeback(cpage, DATA, true);
1662 		f2fs_put_page(cpage, 1);
1663 	}
1664 }
1665 
1666 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
1667 {
1668 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1669 	struct curseg_info *seg_i;
1670 	unsigned char *kaddr;
1671 	struct page *page;
1672 	block_t start;
1673 	int i, j, offset;
1674 
1675 	start = start_sum_block(sbi);
1676 
1677 	page = get_meta_page(sbi, start++);
1678 	kaddr = (unsigned char *)page_address(page);
1679 
1680 	/* Step 1: restore nat cache */
1681 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1682 	memcpy(seg_i->journal, kaddr, SUM_JOURNAL_SIZE);
1683 
1684 	/* Step 2: restore sit cache */
1685 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1686 	memcpy(seg_i->journal, kaddr + SUM_JOURNAL_SIZE, SUM_JOURNAL_SIZE);
1687 	offset = 2 * SUM_JOURNAL_SIZE;
1688 
1689 	/* Step 3: restore summary entries */
1690 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1691 		unsigned short blk_off;
1692 		unsigned int segno;
1693 
1694 		seg_i = CURSEG_I(sbi, i);
1695 		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
1696 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
1697 		seg_i->next_segno = segno;
1698 		reset_curseg(sbi, i, 0);
1699 		seg_i->alloc_type = ckpt->alloc_type[i];
1700 		seg_i->next_blkoff = blk_off;
1701 
1702 		if (seg_i->alloc_type == SSR)
1703 			blk_off = sbi->blocks_per_seg;
1704 
1705 		for (j = 0; j < blk_off; j++) {
1706 			struct f2fs_summary *s;
1707 			s = (struct f2fs_summary *)(kaddr + offset);
1708 			seg_i->sum_blk->entries[j] = *s;
1709 			offset += SUMMARY_SIZE;
1710 			if (offset + SUMMARY_SIZE <= PAGE_SIZE -
1711 						SUM_FOOTER_SIZE)
1712 				continue;
1713 
1714 			f2fs_put_page(page, 1);
1715 			page = NULL;
1716 
1717 			page = get_meta_page(sbi, start++);
1718 			kaddr = (unsigned char *)page_address(page);
1719 			offset = 0;
1720 		}
1721 	}
1722 	f2fs_put_page(page, 1);
1723 	return 0;
1724 }
1725 
1726 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
1727 {
1728 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1729 	struct f2fs_summary_block *sum;
1730 	struct curseg_info *curseg;
1731 	struct page *new;
1732 	unsigned short blk_off;
1733 	unsigned int segno = 0;
1734 	block_t blk_addr = 0;
1735 
1736 	/* get segment number and block addr */
1737 	if (IS_DATASEG(type)) {
1738 		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
1739 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
1740 							CURSEG_HOT_DATA]);
1741 		if (__exist_node_summaries(sbi))
1742 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
1743 		else
1744 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
1745 	} else {
1746 		segno = le32_to_cpu(ckpt->cur_node_segno[type -
1747 							CURSEG_HOT_NODE]);
1748 		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
1749 							CURSEG_HOT_NODE]);
1750 		if (__exist_node_summaries(sbi))
1751 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
1752 							type - CURSEG_HOT_NODE);
1753 		else
1754 			blk_addr = GET_SUM_BLOCK(sbi, segno);
1755 	}
1756 
1757 	new = get_meta_page(sbi, blk_addr);
1758 	sum = (struct f2fs_summary_block *)page_address(new);
1759 
1760 	if (IS_NODESEG(type)) {
1761 		if (__exist_node_summaries(sbi)) {
1762 			struct f2fs_summary *ns = &sum->entries[0];
1763 			int i;
1764 			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
1765 				ns->version = 0;
1766 				ns->ofs_in_node = 0;
1767 			}
1768 		} else {
1769 			int err;
1770 
1771 			err = restore_node_summary(sbi, segno, sum);
1772 			if (err) {
1773 				f2fs_put_page(new, 1);
1774 				return err;
1775 			}
1776 		}
1777 	}
1778 
1779 	/* set uncompleted segment to curseg */
1780 	curseg = CURSEG_I(sbi, type);
1781 	mutex_lock(&curseg->curseg_mutex);
1782 
1783 	/* update journal info */
1784 	down_write(&curseg->journal_rwsem);
1785 	memcpy(curseg->journal, &sum->journal, SUM_JOURNAL_SIZE);
1786 	up_write(&curseg->journal_rwsem);
1787 
1788 	memcpy(curseg->sum_blk->entries, sum->entries, SUM_ENTRY_SIZE);
1789 	memcpy(&curseg->sum_blk->footer, &sum->footer, SUM_FOOTER_SIZE);
1790 	curseg->next_segno = segno;
1791 	reset_curseg(sbi, type, 0);
1792 	curseg->alloc_type = ckpt->alloc_type[type];
1793 	curseg->next_blkoff = blk_off;
1794 	mutex_unlock(&curseg->curseg_mutex);
1795 	f2fs_put_page(new, 1);
1796 	return 0;
1797 }
1798 
1799 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
1800 {
1801 	int type = CURSEG_HOT_DATA;
1802 	int err;
1803 
1804 	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG)) {
1805 		int npages = npages_for_summary_flush(sbi, true);
1806 
1807 		if (npages >= 2)
1808 			ra_meta_pages(sbi, start_sum_block(sbi), npages,
1809 							META_CP, true);
1810 
1811 		/* restore for compacted data summary */
1812 		if (read_compacted_summaries(sbi))
1813 			return -EINVAL;
1814 		type = CURSEG_HOT_NODE;
1815 	}
1816 
1817 	if (__exist_node_summaries(sbi))
1818 		ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
1819 					NR_CURSEG_TYPE - type, META_CP, true);
1820 
1821 	for (; type <= CURSEG_COLD_NODE; type++) {
1822 		err = read_normal_summaries(sbi, type);
1823 		if (err)
1824 			return err;
1825 	}
1826 
1827 	return 0;
1828 }
1829 
1830 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
1831 {
1832 	struct page *page;
1833 	unsigned char *kaddr;
1834 	struct f2fs_summary *summary;
1835 	struct curseg_info *seg_i;
1836 	int written_size = 0;
1837 	int i, j;
1838 
1839 	page = grab_meta_page(sbi, blkaddr++);
1840 	kaddr = (unsigned char *)page_address(page);
1841 
1842 	/* Step 1: write nat cache */
1843 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1844 	memcpy(kaddr, seg_i->journal, SUM_JOURNAL_SIZE);
1845 	written_size += SUM_JOURNAL_SIZE;
1846 
1847 	/* Step 2: write sit cache */
1848 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1849 	memcpy(kaddr + written_size, seg_i->journal, SUM_JOURNAL_SIZE);
1850 	written_size += SUM_JOURNAL_SIZE;
1851 
1852 	/* Step 3: write summary entries */
1853 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1854 		unsigned short blkoff;
1855 		seg_i = CURSEG_I(sbi, i);
1856 		if (sbi->ckpt->alloc_type[i] == SSR)
1857 			blkoff = sbi->blocks_per_seg;
1858 		else
1859 			blkoff = curseg_blkoff(sbi, i);
1860 
1861 		for (j = 0; j < blkoff; j++) {
1862 			if (!page) {
1863 				page = grab_meta_page(sbi, blkaddr++);
1864 				kaddr = (unsigned char *)page_address(page);
1865 				written_size = 0;
1866 			}
1867 			summary = (struct f2fs_summary *)(kaddr + written_size);
1868 			*summary = seg_i->sum_blk->entries[j];
1869 			written_size += SUMMARY_SIZE;
1870 
1871 			if (written_size + SUMMARY_SIZE <= PAGE_SIZE -
1872 							SUM_FOOTER_SIZE)
1873 				continue;
1874 
1875 			set_page_dirty(page);
1876 			f2fs_put_page(page, 1);
1877 			page = NULL;
1878 		}
1879 	}
1880 	if (page) {
1881 		set_page_dirty(page);
1882 		f2fs_put_page(page, 1);
1883 	}
1884 }
1885 
1886 static void write_normal_summaries(struct f2fs_sb_info *sbi,
1887 					block_t blkaddr, int type)
1888 {
1889 	int i, end;
1890 	if (IS_DATASEG(type))
1891 		end = type + NR_CURSEG_DATA_TYPE;
1892 	else
1893 		end = type + NR_CURSEG_NODE_TYPE;
1894 
1895 	for (i = type; i < end; i++)
1896 		write_current_sum_page(sbi, i, blkaddr + (i - type));
1897 }
1898 
1899 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1900 {
1901 	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG))
1902 		write_compacted_summaries(sbi, start_blk);
1903 	else
1904 		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
1905 }
1906 
1907 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1908 {
1909 	write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
1910 }
1911 
1912 int lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
1913 					unsigned int val, int alloc)
1914 {
1915 	int i;
1916 
1917 	if (type == NAT_JOURNAL) {
1918 		for (i = 0; i < nats_in_cursum(journal); i++) {
1919 			if (le32_to_cpu(nid_in_journal(journal, i)) == val)
1920 				return i;
1921 		}
1922 		if (alloc && __has_cursum_space(journal, 1, NAT_JOURNAL))
1923 			return update_nats_in_cursum(journal, 1);
1924 	} else if (type == SIT_JOURNAL) {
1925 		for (i = 0; i < sits_in_cursum(journal); i++)
1926 			if (le32_to_cpu(segno_in_journal(journal, i)) == val)
1927 				return i;
1928 		if (alloc && __has_cursum_space(journal, 1, SIT_JOURNAL))
1929 			return update_sits_in_cursum(journal, 1);
1930 	}
1931 	return -1;
1932 }
1933 
1934 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
1935 					unsigned int segno)
1936 {
1937 	return get_meta_page(sbi, current_sit_addr(sbi, segno));
1938 }
1939 
1940 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
1941 					unsigned int start)
1942 {
1943 	struct sit_info *sit_i = SIT_I(sbi);
1944 	struct page *src_page, *dst_page;
1945 	pgoff_t src_off, dst_off;
1946 	void *src_addr, *dst_addr;
1947 
1948 	src_off = current_sit_addr(sbi, start);
1949 	dst_off = next_sit_addr(sbi, src_off);
1950 
1951 	/* get current sit block page without lock */
1952 	src_page = get_meta_page(sbi, src_off);
1953 	dst_page = grab_meta_page(sbi, dst_off);
1954 	f2fs_bug_on(sbi, PageDirty(src_page));
1955 
1956 	src_addr = page_address(src_page);
1957 	dst_addr = page_address(dst_page);
1958 	memcpy(dst_addr, src_addr, PAGE_SIZE);
1959 
1960 	set_page_dirty(dst_page);
1961 	f2fs_put_page(src_page, 1);
1962 
1963 	set_to_next_sit(sit_i, start);
1964 
1965 	return dst_page;
1966 }
1967 
1968 static struct sit_entry_set *grab_sit_entry_set(void)
1969 {
1970 	struct sit_entry_set *ses =
1971 			f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
1972 
1973 	ses->entry_cnt = 0;
1974 	INIT_LIST_HEAD(&ses->set_list);
1975 	return ses;
1976 }
1977 
1978 static void release_sit_entry_set(struct sit_entry_set *ses)
1979 {
1980 	list_del(&ses->set_list);
1981 	kmem_cache_free(sit_entry_set_slab, ses);
1982 }
1983 
1984 static void adjust_sit_entry_set(struct sit_entry_set *ses,
1985 						struct list_head *head)
1986 {
1987 	struct sit_entry_set *next = ses;
1988 
1989 	if (list_is_last(&ses->set_list, head))
1990 		return;
1991 
1992 	list_for_each_entry_continue(next, head, set_list)
1993 		if (ses->entry_cnt <= next->entry_cnt)
1994 			break;
1995 
1996 	list_move_tail(&ses->set_list, &next->set_list);
1997 }
1998 
1999 static void add_sit_entry(unsigned int segno, struct list_head *head)
2000 {
2001 	struct sit_entry_set *ses;
2002 	unsigned int start_segno = START_SEGNO(segno);
2003 
2004 	list_for_each_entry(ses, head, set_list) {
2005 		if (ses->start_segno == start_segno) {
2006 			ses->entry_cnt++;
2007 			adjust_sit_entry_set(ses, head);
2008 			return;
2009 		}
2010 	}
2011 
2012 	ses = grab_sit_entry_set();
2013 
2014 	ses->start_segno = start_segno;
2015 	ses->entry_cnt++;
2016 	list_add(&ses->set_list, head);
2017 }
2018 
2019 static void add_sits_in_set(struct f2fs_sb_info *sbi)
2020 {
2021 	struct f2fs_sm_info *sm_info = SM_I(sbi);
2022 	struct list_head *set_list = &sm_info->sit_entry_set;
2023 	unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
2024 	unsigned int segno;
2025 
2026 	for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
2027 		add_sit_entry(segno, set_list);
2028 }
2029 
2030 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
2031 {
2032 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2033 	struct f2fs_journal *journal = curseg->journal;
2034 	int i;
2035 
2036 	down_write(&curseg->journal_rwsem);
2037 	for (i = 0; i < sits_in_cursum(journal); i++) {
2038 		unsigned int segno;
2039 		bool dirtied;
2040 
2041 		segno = le32_to_cpu(segno_in_journal(journal, i));
2042 		dirtied = __mark_sit_entry_dirty(sbi, segno);
2043 
2044 		if (!dirtied)
2045 			add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
2046 	}
2047 	update_sits_in_cursum(journal, -i);
2048 	up_write(&curseg->journal_rwsem);
2049 }
2050 
2051 /*
2052  * CP calls this function, which flushes SIT entries including sit_journal,
2053  * and moves prefree segs to free segs.
2054  */
2055 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
2056 {
2057 	struct sit_info *sit_i = SIT_I(sbi);
2058 	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
2059 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2060 	struct f2fs_journal *journal = curseg->journal;
2061 	struct sit_entry_set *ses, *tmp;
2062 	struct list_head *head = &SM_I(sbi)->sit_entry_set;
2063 	bool to_journal = true;
2064 	struct seg_entry *se;
2065 
2066 	mutex_lock(&sit_i->sentry_lock);
2067 
2068 	if (!sit_i->dirty_sentries)
2069 		goto out;
2070 
2071 	/*
2072 	 * add and account sit entries of dirty bitmap in sit entry
2073 	 * set temporarily
2074 	 */
2075 	add_sits_in_set(sbi);
2076 
2077 	/*
2078 	 * if there are no enough space in journal to store dirty sit
2079 	 * entries, remove all entries from journal and add and account
2080 	 * them in sit entry set.
2081 	 */
2082 	if (!__has_cursum_space(journal, sit_i->dirty_sentries, SIT_JOURNAL))
2083 		remove_sits_in_journal(sbi);
2084 
2085 	/*
2086 	 * there are two steps to flush sit entries:
2087 	 * #1, flush sit entries to journal in current cold data summary block.
2088 	 * #2, flush sit entries to sit page.
2089 	 */
2090 	list_for_each_entry_safe(ses, tmp, head, set_list) {
2091 		struct page *page = NULL;
2092 		struct f2fs_sit_block *raw_sit = NULL;
2093 		unsigned int start_segno = ses->start_segno;
2094 		unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
2095 						(unsigned long)MAIN_SEGS(sbi));
2096 		unsigned int segno = start_segno;
2097 
2098 		if (to_journal &&
2099 			!__has_cursum_space(journal, ses->entry_cnt, SIT_JOURNAL))
2100 			to_journal = false;
2101 
2102 		if (to_journal) {
2103 			down_write(&curseg->journal_rwsem);
2104 		} else {
2105 			page = get_next_sit_page(sbi, start_segno);
2106 			raw_sit = page_address(page);
2107 		}
2108 
2109 		/* flush dirty sit entries in region of current sit set */
2110 		for_each_set_bit_from(segno, bitmap, end) {
2111 			int offset, sit_offset;
2112 
2113 			se = get_seg_entry(sbi, segno);
2114 
2115 			/* add discard candidates */
2116 			if (cpc->reason != CP_DISCARD) {
2117 				cpc->trim_start = segno;
2118 				add_discard_addrs(sbi, cpc);
2119 			}
2120 
2121 			if (to_journal) {
2122 				offset = lookup_journal_in_cursum(journal,
2123 							SIT_JOURNAL, segno, 1);
2124 				f2fs_bug_on(sbi, offset < 0);
2125 				segno_in_journal(journal, offset) =
2126 							cpu_to_le32(segno);
2127 				seg_info_to_raw_sit(se,
2128 					&sit_in_journal(journal, offset));
2129 			} else {
2130 				sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
2131 				seg_info_to_raw_sit(se,
2132 						&raw_sit->entries[sit_offset]);
2133 			}
2134 
2135 			__clear_bit(segno, bitmap);
2136 			sit_i->dirty_sentries--;
2137 			ses->entry_cnt--;
2138 		}
2139 
2140 		if (to_journal)
2141 			up_write(&curseg->journal_rwsem);
2142 		else
2143 			f2fs_put_page(page, 1);
2144 
2145 		f2fs_bug_on(sbi, ses->entry_cnt);
2146 		release_sit_entry_set(ses);
2147 	}
2148 
2149 	f2fs_bug_on(sbi, !list_empty(head));
2150 	f2fs_bug_on(sbi, sit_i->dirty_sentries);
2151 out:
2152 	if (cpc->reason == CP_DISCARD) {
2153 		for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
2154 			add_discard_addrs(sbi, cpc);
2155 	}
2156 	mutex_unlock(&sit_i->sentry_lock);
2157 
2158 	set_prefree_as_free_segments(sbi);
2159 }
2160 
2161 static int build_sit_info(struct f2fs_sb_info *sbi)
2162 {
2163 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2164 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2165 	struct sit_info *sit_i;
2166 	unsigned int sit_segs, start;
2167 	char *src_bitmap, *dst_bitmap;
2168 	unsigned int bitmap_size;
2169 
2170 	/* allocate memory for SIT information */
2171 	sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
2172 	if (!sit_i)
2173 		return -ENOMEM;
2174 
2175 	SM_I(sbi)->sit_info = sit_i;
2176 
2177 	sit_i->sentries = f2fs_kvzalloc(MAIN_SEGS(sbi) *
2178 					sizeof(struct seg_entry), GFP_KERNEL);
2179 	if (!sit_i->sentries)
2180 		return -ENOMEM;
2181 
2182 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2183 	sit_i->dirty_sentries_bitmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2184 	if (!sit_i->dirty_sentries_bitmap)
2185 		return -ENOMEM;
2186 
2187 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2188 		sit_i->sentries[start].cur_valid_map
2189 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2190 		sit_i->sentries[start].ckpt_valid_map
2191 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2192 		if (!sit_i->sentries[start].cur_valid_map ||
2193 				!sit_i->sentries[start].ckpt_valid_map)
2194 			return -ENOMEM;
2195 
2196 		if (f2fs_discard_en(sbi)) {
2197 			sit_i->sentries[start].discard_map
2198 				= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2199 			if (!sit_i->sentries[start].discard_map)
2200 				return -ENOMEM;
2201 		}
2202 	}
2203 
2204 	sit_i->tmp_map = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2205 	if (!sit_i->tmp_map)
2206 		return -ENOMEM;
2207 
2208 	if (sbi->segs_per_sec > 1) {
2209 		sit_i->sec_entries = f2fs_kvzalloc(MAIN_SECS(sbi) *
2210 					sizeof(struct sec_entry), GFP_KERNEL);
2211 		if (!sit_i->sec_entries)
2212 			return -ENOMEM;
2213 	}
2214 
2215 	/* get information related with SIT */
2216 	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
2217 
2218 	/* setup SIT bitmap from ckeckpoint pack */
2219 	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
2220 	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
2221 
2222 	dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
2223 	if (!dst_bitmap)
2224 		return -ENOMEM;
2225 
2226 	/* init SIT information */
2227 	sit_i->s_ops = &default_salloc_ops;
2228 
2229 	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
2230 	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
2231 	sit_i->written_valid_blocks = le64_to_cpu(ckpt->valid_block_count);
2232 	sit_i->sit_bitmap = dst_bitmap;
2233 	sit_i->bitmap_size = bitmap_size;
2234 	sit_i->dirty_sentries = 0;
2235 	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
2236 	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
2237 	sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
2238 	mutex_init(&sit_i->sentry_lock);
2239 	return 0;
2240 }
2241 
2242 static int build_free_segmap(struct f2fs_sb_info *sbi)
2243 {
2244 	struct free_segmap_info *free_i;
2245 	unsigned int bitmap_size, sec_bitmap_size;
2246 
2247 	/* allocate memory for free segmap information */
2248 	free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
2249 	if (!free_i)
2250 		return -ENOMEM;
2251 
2252 	SM_I(sbi)->free_info = free_i;
2253 
2254 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2255 	free_i->free_segmap = f2fs_kvmalloc(bitmap_size, GFP_KERNEL);
2256 	if (!free_i->free_segmap)
2257 		return -ENOMEM;
2258 
2259 	sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2260 	free_i->free_secmap = f2fs_kvmalloc(sec_bitmap_size, GFP_KERNEL);
2261 	if (!free_i->free_secmap)
2262 		return -ENOMEM;
2263 
2264 	/* set all segments as dirty temporarily */
2265 	memset(free_i->free_segmap, 0xff, bitmap_size);
2266 	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
2267 
2268 	/* init free segmap information */
2269 	free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
2270 	free_i->free_segments = 0;
2271 	free_i->free_sections = 0;
2272 	spin_lock_init(&free_i->segmap_lock);
2273 	return 0;
2274 }
2275 
2276 static int build_curseg(struct f2fs_sb_info *sbi)
2277 {
2278 	struct curseg_info *array;
2279 	int i;
2280 
2281 	array = kcalloc(NR_CURSEG_TYPE, sizeof(*array), GFP_KERNEL);
2282 	if (!array)
2283 		return -ENOMEM;
2284 
2285 	SM_I(sbi)->curseg_array = array;
2286 
2287 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
2288 		mutex_init(&array[i].curseg_mutex);
2289 		array[i].sum_blk = kzalloc(PAGE_SIZE, GFP_KERNEL);
2290 		if (!array[i].sum_blk)
2291 			return -ENOMEM;
2292 		init_rwsem(&array[i].journal_rwsem);
2293 		array[i].journal = kzalloc(sizeof(struct f2fs_journal),
2294 							GFP_KERNEL);
2295 		if (!array[i].journal)
2296 			return -ENOMEM;
2297 		array[i].segno = NULL_SEGNO;
2298 		array[i].next_blkoff = 0;
2299 	}
2300 	return restore_curseg_summaries(sbi);
2301 }
2302 
2303 static void build_sit_entries(struct f2fs_sb_info *sbi)
2304 {
2305 	struct sit_info *sit_i = SIT_I(sbi);
2306 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2307 	struct f2fs_journal *journal = curseg->journal;
2308 	int sit_blk_cnt = SIT_BLK_CNT(sbi);
2309 	unsigned int i, start, end;
2310 	unsigned int readed, start_blk = 0;
2311 	int nrpages = MAX_BIO_BLOCKS(sbi) * 8;
2312 
2313 	do {
2314 		readed = ra_meta_pages(sbi, start_blk, nrpages, META_SIT, true);
2315 
2316 		start = start_blk * sit_i->sents_per_block;
2317 		end = (start_blk + readed) * sit_i->sents_per_block;
2318 
2319 		for (; start < end && start < MAIN_SEGS(sbi); start++) {
2320 			struct seg_entry *se = &sit_i->sentries[start];
2321 			struct f2fs_sit_block *sit_blk;
2322 			struct f2fs_sit_entry sit;
2323 			struct page *page;
2324 
2325 			page = get_current_sit_page(sbi, start);
2326 			sit_blk = (struct f2fs_sit_block *)page_address(page);
2327 			sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
2328 			f2fs_put_page(page, 1);
2329 
2330 			check_block_count(sbi, start, &sit);
2331 			seg_info_from_raw_sit(se, &sit);
2332 
2333 			/* build discard map only one time */
2334 			if (f2fs_discard_en(sbi)) {
2335 				memcpy(se->discard_map, se->cur_valid_map,
2336 							SIT_VBLOCK_MAP_SIZE);
2337 				sbi->discard_blks += sbi->blocks_per_seg -
2338 							se->valid_blocks;
2339 			}
2340 
2341 			if (sbi->segs_per_sec > 1)
2342 				get_sec_entry(sbi, start)->valid_blocks +=
2343 							se->valid_blocks;
2344 		}
2345 		start_blk += readed;
2346 	} while (start_blk < sit_blk_cnt);
2347 
2348 	down_read(&curseg->journal_rwsem);
2349 	for (i = 0; i < sits_in_cursum(journal); i++) {
2350 		struct f2fs_sit_entry sit;
2351 		struct seg_entry *se;
2352 		unsigned int old_valid_blocks;
2353 
2354 		start = le32_to_cpu(segno_in_journal(journal, i));
2355 		se = &sit_i->sentries[start];
2356 		sit = sit_in_journal(journal, i);
2357 
2358 		old_valid_blocks = se->valid_blocks;
2359 
2360 		check_block_count(sbi, start, &sit);
2361 		seg_info_from_raw_sit(se, &sit);
2362 
2363 		if (f2fs_discard_en(sbi)) {
2364 			memcpy(se->discard_map, se->cur_valid_map,
2365 						SIT_VBLOCK_MAP_SIZE);
2366 			sbi->discard_blks += old_valid_blocks -
2367 						se->valid_blocks;
2368 		}
2369 
2370 		if (sbi->segs_per_sec > 1)
2371 			get_sec_entry(sbi, start)->valid_blocks +=
2372 				se->valid_blocks - old_valid_blocks;
2373 	}
2374 	up_read(&curseg->journal_rwsem);
2375 }
2376 
2377 static void init_free_segmap(struct f2fs_sb_info *sbi)
2378 {
2379 	unsigned int start;
2380 	int type;
2381 
2382 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2383 		struct seg_entry *sentry = get_seg_entry(sbi, start);
2384 		if (!sentry->valid_blocks)
2385 			__set_free(sbi, start);
2386 	}
2387 
2388 	/* set use the current segments */
2389 	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
2390 		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
2391 		__set_test_and_inuse(sbi, curseg_t->segno);
2392 	}
2393 }
2394 
2395 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
2396 {
2397 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2398 	struct free_segmap_info *free_i = FREE_I(sbi);
2399 	unsigned int segno = 0, offset = 0;
2400 	unsigned short valid_blocks;
2401 
2402 	while (1) {
2403 		/* find dirty segment based on free segmap */
2404 		segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
2405 		if (segno >= MAIN_SEGS(sbi))
2406 			break;
2407 		offset = segno + 1;
2408 		valid_blocks = get_valid_blocks(sbi, segno, 0);
2409 		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
2410 			continue;
2411 		if (valid_blocks > sbi->blocks_per_seg) {
2412 			f2fs_bug_on(sbi, 1);
2413 			continue;
2414 		}
2415 		mutex_lock(&dirty_i->seglist_lock);
2416 		__locate_dirty_segment(sbi, segno, DIRTY);
2417 		mutex_unlock(&dirty_i->seglist_lock);
2418 	}
2419 }
2420 
2421 static int init_victim_secmap(struct f2fs_sb_info *sbi)
2422 {
2423 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2424 	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2425 
2426 	dirty_i->victim_secmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2427 	if (!dirty_i->victim_secmap)
2428 		return -ENOMEM;
2429 	return 0;
2430 }
2431 
2432 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
2433 {
2434 	struct dirty_seglist_info *dirty_i;
2435 	unsigned int bitmap_size, i;
2436 
2437 	/* allocate memory for dirty segments list information */
2438 	dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
2439 	if (!dirty_i)
2440 		return -ENOMEM;
2441 
2442 	SM_I(sbi)->dirty_info = dirty_i;
2443 	mutex_init(&dirty_i->seglist_lock);
2444 
2445 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2446 
2447 	for (i = 0; i < NR_DIRTY_TYPE; i++) {
2448 		dirty_i->dirty_segmap[i] = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2449 		if (!dirty_i->dirty_segmap[i])
2450 			return -ENOMEM;
2451 	}
2452 
2453 	init_dirty_segmap(sbi);
2454 	return init_victim_secmap(sbi);
2455 }
2456 
2457 /*
2458  * Update min, max modified time for cost-benefit GC algorithm
2459  */
2460 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
2461 {
2462 	struct sit_info *sit_i = SIT_I(sbi);
2463 	unsigned int segno;
2464 
2465 	mutex_lock(&sit_i->sentry_lock);
2466 
2467 	sit_i->min_mtime = LLONG_MAX;
2468 
2469 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
2470 		unsigned int i;
2471 		unsigned long long mtime = 0;
2472 
2473 		for (i = 0; i < sbi->segs_per_sec; i++)
2474 			mtime += get_seg_entry(sbi, segno + i)->mtime;
2475 
2476 		mtime = div_u64(mtime, sbi->segs_per_sec);
2477 
2478 		if (sit_i->min_mtime > mtime)
2479 			sit_i->min_mtime = mtime;
2480 	}
2481 	sit_i->max_mtime = get_mtime(sbi);
2482 	mutex_unlock(&sit_i->sentry_lock);
2483 }
2484 
2485 int build_segment_manager(struct f2fs_sb_info *sbi)
2486 {
2487 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2488 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2489 	struct f2fs_sm_info *sm_info;
2490 	int err;
2491 
2492 	sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
2493 	if (!sm_info)
2494 		return -ENOMEM;
2495 
2496 	/* init sm info */
2497 	sbi->sm_info = sm_info;
2498 	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
2499 	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
2500 	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
2501 	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
2502 	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
2503 	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
2504 	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
2505 	sm_info->rec_prefree_segments = sm_info->main_segments *
2506 					DEF_RECLAIM_PREFREE_SEGMENTS / 100;
2507 	if (sm_info->rec_prefree_segments > DEF_MAX_RECLAIM_PREFREE_SEGMENTS)
2508 		sm_info->rec_prefree_segments = DEF_MAX_RECLAIM_PREFREE_SEGMENTS;
2509 
2510 	if (!test_opt(sbi, LFS))
2511 		sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
2512 	sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
2513 	sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
2514 
2515 	INIT_LIST_HEAD(&sm_info->discard_list);
2516 	INIT_LIST_HEAD(&sm_info->wait_list);
2517 	sm_info->nr_discards = 0;
2518 	sm_info->max_discards = 0;
2519 
2520 	sm_info->trim_sections = DEF_BATCHED_TRIM_SECTIONS;
2521 
2522 	INIT_LIST_HEAD(&sm_info->sit_entry_set);
2523 
2524 	if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) {
2525 		err = create_flush_cmd_control(sbi);
2526 		if (err)
2527 			return err;
2528 	}
2529 
2530 	err = build_sit_info(sbi);
2531 	if (err)
2532 		return err;
2533 	err = build_free_segmap(sbi);
2534 	if (err)
2535 		return err;
2536 	err = build_curseg(sbi);
2537 	if (err)
2538 		return err;
2539 
2540 	/* reinit free segmap based on SIT */
2541 	build_sit_entries(sbi);
2542 
2543 	init_free_segmap(sbi);
2544 	err = build_dirty_segmap(sbi);
2545 	if (err)
2546 		return err;
2547 
2548 	init_min_max_mtime(sbi);
2549 	return 0;
2550 }
2551 
2552 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
2553 		enum dirty_type dirty_type)
2554 {
2555 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2556 
2557 	mutex_lock(&dirty_i->seglist_lock);
2558 	kvfree(dirty_i->dirty_segmap[dirty_type]);
2559 	dirty_i->nr_dirty[dirty_type] = 0;
2560 	mutex_unlock(&dirty_i->seglist_lock);
2561 }
2562 
2563 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
2564 {
2565 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2566 	kvfree(dirty_i->victim_secmap);
2567 }
2568 
2569 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
2570 {
2571 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2572 	int i;
2573 
2574 	if (!dirty_i)
2575 		return;
2576 
2577 	/* discard pre-free/dirty segments list */
2578 	for (i = 0; i < NR_DIRTY_TYPE; i++)
2579 		discard_dirty_segmap(sbi, i);
2580 
2581 	destroy_victim_secmap(sbi);
2582 	SM_I(sbi)->dirty_info = NULL;
2583 	kfree(dirty_i);
2584 }
2585 
2586 static void destroy_curseg(struct f2fs_sb_info *sbi)
2587 {
2588 	struct curseg_info *array = SM_I(sbi)->curseg_array;
2589 	int i;
2590 
2591 	if (!array)
2592 		return;
2593 	SM_I(sbi)->curseg_array = NULL;
2594 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
2595 		kfree(array[i].sum_blk);
2596 		kfree(array[i].journal);
2597 	}
2598 	kfree(array);
2599 }
2600 
2601 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
2602 {
2603 	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
2604 	if (!free_i)
2605 		return;
2606 	SM_I(sbi)->free_info = NULL;
2607 	kvfree(free_i->free_segmap);
2608 	kvfree(free_i->free_secmap);
2609 	kfree(free_i);
2610 }
2611 
2612 static void destroy_sit_info(struct f2fs_sb_info *sbi)
2613 {
2614 	struct sit_info *sit_i = SIT_I(sbi);
2615 	unsigned int start;
2616 
2617 	if (!sit_i)
2618 		return;
2619 
2620 	if (sit_i->sentries) {
2621 		for (start = 0; start < MAIN_SEGS(sbi); start++) {
2622 			kfree(sit_i->sentries[start].cur_valid_map);
2623 			kfree(sit_i->sentries[start].ckpt_valid_map);
2624 			kfree(sit_i->sentries[start].discard_map);
2625 		}
2626 	}
2627 	kfree(sit_i->tmp_map);
2628 
2629 	kvfree(sit_i->sentries);
2630 	kvfree(sit_i->sec_entries);
2631 	kvfree(sit_i->dirty_sentries_bitmap);
2632 
2633 	SM_I(sbi)->sit_info = NULL;
2634 	kfree(sit_i->sit_bitmap);
2635 	kfree(sit_i);
2636 }
2637 
2638 void destroy_segment_manager(struct f2fs_sb_info *sbi)
2639 {
2640 	struct f2fs_sm_info *sm_info = SM_I(sbi);
2641 
2642 	if (!sm_info)
2643 		return;
2644 	destroy_flush_cmd_control(sbi);
2645 	destroy_dirty_segmap(sbi);
2646 	destroy_curseg(sbi);
2647 	destroy_free_segmap(sbi);
2648 	destroy_sit_info(sbi);
2649 	sbi->sm_info = NULL;
2650 	kfree(sm_info);
2651 }
2652 
2653 int __init create_segment_manager_caches(void)
2654 {
2655 	discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
2656 			sizeof(struct discard_entry));
2657 	if (!discard_entry_slab)
2658 		goto fail;
2659 
2660 	bio_entry_slab = f2fs_kmem_cache_create("bio_entry",
2661 			sizeof(struct bio_entry));
2662 	if (!bio_entry_slab)
2663 		goto destroy_discard_entry;
2664 
2665 	sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
2666 			sizeof(struct sit_entry_set));
2667 	if (!sit_entry_set_slab)
2668 		goto destroy_bio_entry;
2669 
2670 	inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
2671 			sizeof(struct inmem_pages));
2672 	if (!inmem_entry_slab)
2673 		goto destroy_sit_entry_set;
2674 	return 0;
2675 
2676 destroy_sit_entry_set:
2677 	kmem_cache_destroy(sit_entry_set_slab);
2678 destroy_bio_entry:
2679 	kmem_cache_destroy(bio_entry_slab);
2680 destroy_discard_entry:
2681 	kmem_cache_destroy(discard_entry_slab);
2682 fail:
2683 	return -ENOMEM;
2684 }
2685 
2686 void destroy_segment_manager_caches(void)
2687 {
2688 	kmem_cache_destroy(sit_entry_set_slab);
2689 	kmem_cache_destroy(bio_entry_slab);
2690 	kmem_cache_destroy(discard_entry_slab);
2691 	kmem_cache_destroy(inmem_entry_slab);
2692 }
2693