xref: /openbmc/linux/fs/f2fs/segment.c (revision ba48a33ef6faa573257b2a4181329f2d1eaafed9)
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 *discard_cmd_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 	mutex_lock(&fi->inmem_lock);
246 	__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
247 	mutex_unlock(&fi->inmem_lock);
248 
249 	clear_inode_flag(inode, FI_ATOMIC_FILE);
250 	stat_dec_atomic_write(inode);
251 }
252 
253 void drop_inmem_page(struct inode *inode, struct page *page)
254 {
255 	struct f2fs_inode_info *fi = F2FS_I(inode);
256 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
257 	struct list_head *head = &fi->inmem_pages;
258 	struct inmem_pages *cur = NULL;
259 
260 	f2fs_bug_on(sbi, !IS_ATOMIC_WRITTEN_PAGE(page));
261 
262 	mutex_lock(&fi->inmem_lock);
263 	list_for_each_entry(cur, head, list) {
264 		if (cur->page == page)
265 			break;
266 	}
267 
268 	f2fs_bug_on(sbi, !cur || cur->page != page);
269 	list_del(&cur->list);
270 	mutex_unlock(&fi->inmem_lock);
271 
272 	dec_page_count(sbi, F2FS_INMEM_PAGES);
273 	kmem_cache_free(inmem_entry_slab, cur);
274 
275 	ClearPageUptodate(page);
276 	set_page_private(page, 0);
277 	ClearPagePrivate(page);
278 	f2fs_put_page(page, 0);
279 
280 	trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE);
281 }
282 
283 static int __commit_inmem_pages(struct inode *inode,
284 					struct list_head *revoke_list)
285 {
286 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
287 	struct f2fs_inode_info *fi = F2FS_I(inode);
288 	struct inmem_pages *cur, *tmp;
289 	struct f2fs_io_info fio = {
290 		.sbi = sbi,
291 		.type = DATA,
292 		.op = REQ_OP_WRITE,
293 		.op_flags = REQ_SYNC | REQ_PRIO,
294 		.encrypted_page = NULL,
295 	};
296 	pgoff_t last_idx = ULONG_MAX;
297 	int err = 0;
298 
299 	list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
300 		struct page *page = cur->page;
301 
302 		lock_page(page);
303 		if (page->mapping == inode->i_mapping) {
304 			trace_f2fs_commit_inmem_page(page, INMEM);
305 
306 			set_page_dirty(page);
307 			f2fs_wait_on_page_writeback(page, DATA, true);
308 			if (clear_page_dirty_for_io(page)) {
309 				inode_dec_dirty_pages(inode);
310 				remove_dirty_inode(inode);
311 			}
312 
313 			fio.page = page;
314 			err = do_write_data_page(&fio);
315 			if (err) {
316 				unlock_page(page);
317 				break;
318 			}
319 
320 			/* record old blkaddr for revoking */
321 			cur->old_addr = fio.old_blkaddr;
322 			last_idx = page->index;
323 		}
324 		unlock_page(page);
325 		list_move_tail(&cur->list, revoke_list);
326 	}
327 
328 	if (last_idx != ULONG_MAX)
329 		f2fs_submit_merged_bio_cond(sbi, inode, 0, last_idx,
330 							DATA, WRITE);
331 
332 	if (!err)
333 		__revoke_inmem_pages(inode, revoke_list, false, false);
334 
335 	return err;
336 }
337 
338 int commit_inmem_pages(struct inode *inode)
339 {
340 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
341 	struct f2fs_inode_info *fi = F2FS_I(inode);
342 	struct list_head revoke_list;
343 	int err;
344 
345 	INIT_LIST_HEAD(&revoke_list);
346 	f2fs_balance_fs(sbi, true);
347 	f2fs_lock_op(sbi);
348 
349 	set_inode_flag(inode, FI_ATOMIC_COMMIT);
350 
351 	mutex_lock(&fi->inmem_lock);
352 	err = __commit_inmem_pages(inode, &revoke_list);
353 	if (err) {
354 		int ret;
355 		/*
356 		 * try to revoke all committed pages, but still we could fail
357 		 * due to no memory or other reason, if that happened, EAGAIN
358 		 * will be returned, which means in such case, transaction is
359 		 * already not integrity, caller should use journal to do the
360 		 * recovery or rewrite & commit last transaction. For other
361 		 * error number, revoking was done by filesystem itself.
362 		 */
363 		ret = __revoke_inmem_pages(inode, &revoke_list, false, true);
364 		if (ret)
365 			err = ret;
366 
367 		/* drop all uncommitted pages */
368 		__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
369 	}
370 	mutex_unlock(&fi->inmem_lock);
371 
372 	clear_inode_flag(inode, FI_ATOMIC_COMMIT);
373 
374 	f2fs_unlock_op(sbi);
375 	return err;
376 }
377 
378 /*
379  * This function balances dirty node and dentry pages.
380  * In addition, it controls garbage collection.
381  */
382 void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
383 {
384 #ifdef CONFIG_F2FS_FAULT_INJECTION
385 	if (time_to_inject(sbi, FAULT_CHECKPOINT)) {
386 		f2fs_show_injection_info(FAULT_CHECKPOINT);
387 		f2fs_stop_checkpoint(sbi, false);
388 	}
389 #endif
390 
391 	if (!need)
392 		return;
393 
394 	/* balance_fs_bg is able to be pending */
395 	if (excess_cached_nats(sbi))
396 		f2fs_balance_fs_bg(sbi);
397 
398 	/*
399 	 * We should do GC or end up with checkpoint, if there are so many dirty
400 	 * dir/node pages without enough free segments.
401 	 */
402 	if (has_not_enough_free_secs(sbi, 0, 0)) {
403 		mutex_lock(&sbi->gc_mutex);
404 		f2fs_gc(sbi, false, false);
405 	}
406 }
407 
408 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
409 {
410 	/* try to shrink extent cache when there is no enough memory */
411 	if (!available_free_memory(sbi, EXTENT_CACHE))
412 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
413 
414 	/* check the # of cached NAT entries */
415 	if (!available_free_memory(sbi, NAT_ENTRIES))
416 		try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
417 
418 	if (!available_free_memory(sbi, FREE_NIDS))
419 		try_to_free_nids(sbi, MAX_FREE_NIDS);
420 	else
421 		build_free_nids(sbi, false, false);
422 
423 	if (!is_idle(sbi))
424 		return;
425 
426 	/* checkpoint is the only way to shrink partial cached entries */
427 	if (!available_free_memory(sbi, NAT_ENTRIES) ||
428 			!available_free_memory(sbi, INO_ENTRIES) ||
429 			excess_prefree_segs(sbi) ||
430 			excess_dirty_nats(sbi) ||
431 			f2fs_time_over(sbi, CP_TIME)) {
432 		if (test_opt(sbi, DATA_FLUSH)) {
433 			struct blk_plug plug;
434 
435 			blk_start_plug(&plug);
436 			sync_dirty_inodes(sbi, FILE_INODE);
437 			blk_finish_plug(&plug);
438 		}
439 		f2fs_sync_fs(sbi->sb, true);
440 		stat_inc_bg_cp_count(sbi->stat_info);
441 	}
442 }
443 
444 static int __submit_flush_wait(struct f2fs_sb_info *sbi,
445 				struct block_device *bdev)
446 {
447 	struct bio *bio = f2fs_bio_alloc(0);
448 	int ret;
449 
450 	bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
451 	bio->bi_bdev = bdev;
452 	ret = submit_bio_wait(bio);
453 	bio_put(bio);
454 
455 	trace_f2fs_issue_flush(bdev, test_opt(sbi, NOBARRIER),
456 				test_opt(sbi, FLUSH_MERGE), ret);
457 	return ret;
458 }
459 
460 static int submit_flush_wait(struct f2fs_sb_info *sbi)
461 {
462 	int ret = __submit_flush_wait(sbi, sbi->sb->s_bdev);
463 	int i;
464 
465 	if (!sbi->s_ndevs || ret)
466 		return ret;
467 
468 	for (i = 1; i < sbi->s_ndevs; i++) {
469 		ret = __submit_flush_wait(sbi, FDEV(i).bdev);
470 		if (ret)
471 			break;
472 	}
473 	return ret;
474 }
475 
476 static int issue_flush_thread(void *data)
477 {
478 	struct f2fs_sb_info *sbi = data;
479 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
480 	wait_queue_head_t *q = &fcc->flush_wait_queue;
481 repeat:
482 	if (kthread_should_stop())
483 		return 0;
484 
485 	if (!llist_empty(&fcc->issue_list)) {
486 		struct flush_cmd *cmd, *next;
487 		int ret;
488 
489 		fcc->dispatch_list = llist_del_all(&fcc->issue_list);
490 		fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
491 
492 		ret = submit_flush_wait(sbi);
493 		atomic_inc(&fcc->issued_flush);
494 
495 		llist_for_each_entry_safe(cmd, next,
496 					  fcc->dispatch_list, llnode) {
497 			cmd->ret = ret;
498 			complete(&cmd->wait);
499 		}
500 		fcc->dispatch_list = NULL;
501 	}
502 
503 	wait_event_interruptible(*q,
504 		kthread_should_stop() || !llist_empty(&fcc->issue_list));
505 	goto repeat;
506 }
507 
508 int f2fs_issue_flush(struct f2fs_sb_info *sbi)
509 {
510 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
511 	struct flush_cmd cmd;
512 	int ret;
513 
514 	if (test_opt(sbi, NOBARRIER))
515 		return 0;
516 
517 	if (!test_opt(sbi, FLUSH_MERGE)) {
518 		ret = submit_flush_wait(sbi);
519 		atomic_inc(&fcc->issued_flush);
520 		return ret;
521 	}
522 
523 	if (!atomic_read(&fcc->issing_flush)) {
524 		atomic_inc(&fcc->issing_flush);
525 		ret = submit_flush_wait(sbi);
526 		atomic_dec(&fcc->issing_flush);
527 
528 		atomic_inc(&fcc->issued_flush);
529 		return ret;
530 	}
531 
532 	init_completion(&cmd.wait);
533 
534 	atomic_inc(&fcc->issing_flush);
535 	llist_add(&cmd.llnode, &fcc->issue_list);
536 
537 	if (!fcc->dispatch_list)
538 		wake_up(&fcc->flush_wait_queue);
539 
540 	if (fcc->f2fs_issue_flush) {
541 		wait_for_completion(&cmd.wait);
542 		atomic_dec(&fcc->issing_flush);
543 	} else {
544 		llist_del_all(&fcc->issue_list);
545 		atomic_set(&fcc->issing_flush, 0);
546 	}
547 
548 	return cmd.ret;
549 }
550 
551 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
552 {
553 	dev_t dev = sbi->sb->s_bdev->bd_dev;
554 	struct flush_cmd_control *fcc;
555 	int err = 0;
556 
557 	if (SM_I(sbi)->fcc_info) {
558 		fcc = SM_I(sbi)->fcc_info;
559 		goto init_thread;
560 	}
561 
562 	fcc = kzalloc(sizeof(struct flush_cmd_control), GFP_KERNEL);
563 	if (!fcc)
564 		return -ENOMEM;
565 	atomic_set(&fcc->issued_flush, 0);
566 	atomic_set(&fcc->issing_flush, 0);
567 	init_waitqueue_head(&fcc->flush_wait_queue);
568 	init_llist_head(&fcc->issue_list);
569 	SM_I(sbi)->fcc_info = fcc;
570 init_thread:
571 	fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
572 				"f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
573 	if (IS_ERR(fcc->f2fs_issue_flush)) {
574 		err = PTR_ERR(fcc->f2fs_issue_flush);
575 		kfree(fcc);
576 		SM_I(sbi)->fcc_info = NULL;
577 		return err;
578 	}
579 
580 	return err;
581 }
582 
583 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi, bool free)
584 {
585 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
586 
587 	if (fcc && fcc->f2fs_issue_flush) {
588 		struct task_struct *flush_thread = fcc->f2fs_issue_flush;
589 
590 		fcc->f2fs_issue_flush = NULL;
591 		kthread_stop(flush_thread);
592 	}
593 	if (free) {
594 		kfree(fcc);
595 		SM_I(sbi)->fcc_info = NULL;
596 	}
597 }
598 
599 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
600 		enum dirty_type dirty_type)
601 {
602 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
603 
604 	/* need not be added */
605 	if (IS_CURSEG(sbi, segno))
606 		return;
607 
608 	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
609 		dirty_i->nr_dirty[dirty_type]++;
610 
611 	if (dirty_type == DIRTY) {
612 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
613 		enum dirty_type t = sentry->type;
614 
615 		if (unlikely(t >= DIRTY)) {
616 			f2fs_bug_on(sbi, 1);
617 			return;
618 		}
619 		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
620 			dirty_i->nr_dirty[t]++;
621 	}
622 }
623 
624 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
625 		enum dirty_type dirty_type)
626 {
627 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
628 
629 	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
630 		dirty_i->nr_dirty[dirty_type]--;
631 
632 	if (dirty_type == DIRTY) {
633 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
634 		enum dirty_type t = sentry->type;
635 
636 		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
637 			dirty_i->nr_dirty[t]--;
638 
639 		if (get_valid_blocks(sbi, segno, true) == 0)
640 			clear_bit(GET_SEC_FROM_SEG(sbi, segno),
641 						dirty_i->victim_secmap);
642 	}
643 }
644 
645 /*
646  * Should not occur error such as -ENOMEM.
647  * Adding dirty entry into seglist is not critical operation.
648  * If a given segment is one of current working segments, it won't be added.
649  */
650 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
651 {
652 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
653 	unsigned short valid_blocks;
654 
655 	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
656 		return;
657 
658 	mutex_lock(&dirty_i->seglist_lock);
659 
660 	valid_blocks = get_valid_blocks(sbi, segno, false);
661 
662 	if (valid_blocks == 0) {
663 		__locate_dirty_segment(sbi, segno, PRE);
664 		__remove_dirty_segment(sbi, segno, DIRTY);
665 	} else if (valid_blocks < sbi->blocks_per_seg) {
666 		__locate_dirty_segment(sbi, segno, DIRTY);
667 	} else {
668 		/* Recovery routine with SSR needs this */
669 		__remove_dirty_segment(sbi, segno, DIRTY);
670 	}
671 
672 	mutex_unlock(&dirty_i->seglist_lock);
673 }
674 
675 static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
676 		struct block_device *bdev, block_t lstart,
677 		block_t start, block_t len)
678 {
679 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
680 	struct list_head *pend_list;
681 	struct discard_cmd *dc;
682 
683 	f2fs_bug_on(sbi, !len);
684 
685 	pend_list = &dcc->pend_list[plist_idx(len)];
686 
687 	dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS);
688 	INIT_LIST_HEAD(&dc->list);
689 	dc->bdev = bdev;
690 	dc->lstart = lstart;
691 	dc->start = start;
692 	dc->len = len;
693 	dc->state = D_PREP;
694 	dc->error = 0;
695 	init_completion(&dc->wait);
696 	list_add_tail(&dc->list, pend_list);
697 	atomic_inc(&dcc->discard_cmd_cnt);
698 
699 	return dc;
700 }
701 
702 static struct discard_cmd *__attach_discard_cmd(struct f2fs_sb_info *sbi,
703 				struct block_device *bdev, block_t lstart,
704 				block_t start, block_t len,
705 				struct rb_node *parent, struct rb_node **p)
706 {
707 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
708 	struct discard_cmd *dc;
709 
710 	dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
711 
712 	rb_link_node(&dc->rb_node, parent, p);
713 	rb_insert_color(&dc->rb_node, &dcc->root);
714 
715 	return dc;
716 }
717 
718 static void __detach_discard_cmd(struct discard_cmd_control *dcc,
719 							struct discard_cmd *dc)
720 {
721 	if (dc->state == D_DONE)
722 		atomic_dec(&dcc->issing_discard);
723 
724 	list_del(&dc->list);
725 	rb_erase(&dc->rb_node, &dcc->root);
726 
727 	kmem_cache_free(discard_cmd_slab, dc);
728 
729 	atomic_dec(&dcc->discard_cmd_cnt);
730 }
731 
732 static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
733 							struct discard_cmd *dc)
734 {
735 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
736 
737 	if (dc->error == -EOPNOTSUPP)
738 		dc->error = 0;
739 
740 	if (dc->error)
741 		f2fs_msg(sbi->sb, KERN_INFO,
742 				"Issue discard failed, ret: %d", dc->error);
743 	__detach_discard_cmd(dcc, dc);
744 }
745 
746 static void f2fs_submit_discard_endio(struct bio *bio)
747 {
748 	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
749 
750 	dc->error = bio->bi_error;
751 	dc->state = D_DONE;
752 	complete(&dc->wait);
753 	bio_put(bio);
754 }
755 
756 /* this function is copied from blkdev_issue_discard from block/blk-lib.c */
757 static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
758 				struct discard_cmd *dc)
759 {
760 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
761 	struct bio *bio = NULL;
762 
763 	if (dc->state != D_PREP)
764 		return;
765 
766 	dc->error = __blkdev_issue_discard(dc->bdev,
767 				SECTOR_FROM_BLOCK(dc->start),
768 				SECTOR_FROM_BLOCK(dc->len),
769 				GFP_NOFS, 0, &bio);
770 	if (!dc->error) {
771 		/* should keep before submission to avoid D_DONE right away */
772 		dc->state = D_SUBMIT;
773 		atomic_inc(&dcc->issued_discard);
774 		atomic_inc(&dcc->issing_discard);
775 		if (bio) {
776 			bio->bi_private = dc;
777 			bio->bi_end_io = f2fs_submit_discard_endio;
778 			bio->bi_opf |= REQ_SYNC;
779 			submit_bio(bio);
780 			list_move_tail(&dc->list, &dcc->wait_list);
781 		}
782 	} else {
783 		__remove_discard_cmd(sbi, dc);
784 	}
785 }
786 
787 static struct discard_cmd *__insert_discard_tree(struct f2fs_sb_info *sbi,
788 				struct block_device *bdev, block_t lstart,
789 				block_t start, block_t len,
790 				struct rb_node **insert_p,
791 				struct rb_node *insert_parent)
792 {
793 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
794 	struct rb_node **p = &dcc->root.rb_node;
795 	struct rb_node *parent = NULL;
796 	struct discard_cmd *dc = NULL;
797 
798 	if (insert_p && insert_parent) {
799 		parent = insert_parent;
800 		p = insert_p;
801 		goto do_insert;
802 	}
803 
804 	p = __lookup_rb_tree_for_insert(sbi, &dcc->root, &parent, lstart);
805 do_insert:
806 	dc = __attach_discard_cmd(sbi, bdev, lstart, start, len, parent, p);
807 	if (!dc)
808 		return NULL;
809 
810 	return dc;
811 }
812 
813 static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
814 						struct discard_cmd *dc)
815 {
816 	list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
817 }
818 
819 static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
820 				struct discard_cmd *dc, block_t blkaddr)
821 {
822 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
823 	struct discard_info di = dc->di;
824 	bool modified = false;
825 
826 	if (dc->state == D_DONE || dc->len == 1) {
827 		__remove_discard_cmd(sbi, dc);
828 		return;
829 	}
830 
831 	if (blkaddr > di.lstart) {
832 		dc->len = blkaddr - dc->lstart;
833 		__relocate_discard_cmd(dcc, dc);
834 		modified = true;
835 	}
836 
837 	if (blkaddr < di.lstart + di.len - 1) {
838 		if (modified) {
839 			__insert_discard_tree(sbi, dc->bdev, blkaddr + 1,
840 					di.start + blkaddr + 1 - di.lstart,
841 					di.lstart + di.len - 1 - blkaddr,
842 					NULL, NULL);
843 		} else {
844 			dc->lstart++;
845 			dc->len--;
846 			dc->start++;
847 			__relocate_discard_cmd(dcc, dc);
848 		}
849 	}
850 }
851 
852 static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
853 				struct block_device *bdev, block_t lstart,
854 				block_t start, block_t len)
855 {
856 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
857 	struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
858 	struct discard_cmd *dc;
859 	struct discard_info di = {0};
860 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
861 	block_t end = lstart + len;
862 
863 	mutex_lock(&dcc->cmd_lock);
864 
865 	dc = (struct discard_cmd *)__lookup_rb_tree_ret(&dcc->root,
866 					NULL, lstart,
867 					(struct rb_entry **)&prev_dc,
868 					(struct rb_entry **)&next_dc,
869 					&insert_p, &insert_parent, true);
870 	if (dc)
871 		prev_dc = dc;
872 
873 	if (!prev_dc) {
874 		di.lstart = lstart;
875 		di.len = next_dc ? next_dc->lstart - lstart : len;
876 		di.len = min(di.len, len);
877 		di.start = start;
878 	}
879 
880 	while (1) {
881 		struct rb_node *node;
882 		bool merged = false;
883 		struct discard_cmd *tdc = NULL;
884 
885 		if (prev_dc) {
886 			di.lstart = prev_dc->lstart + prev_dc->len;
887 			if (di.lstart < lstart)
888 				di.lstart = lstart;
889 			if (di.lstart >= end)
890 				break;
891 
892 			if (!next_dc || next_dc->lstart > end)
893 				di.len = end - di.lstart;
894 			else
895 				di.len = next_dc->lstart - di.lstart;
896 			di.start = start + di.lstart - lstart;
897 		}
898 
899 		if (!di.len)
900 			goto next;
901 
902 		if (prev_dc && prev_dc->state == D_PREP &&
903 			prev_dc->bdev == bdev &&
904 			__is_discard_back_mergeable(&di, &prev_dc->di)) {
905 			prev_dc->di.len += di.len;
906 			__relocate_discard_cmd(dcc, prev_dc);
907 			di = prev_dc->di;
908 			tdc = prev_dc;
909 			merged = true;
910 		}
911 
912 		if (next_dc && next_dc->state == D_PREP &&
913 			next_dc->bdev == bdev &&
914 			__is_discard_front_mergeable(&di, &next_dc->di)) {
915 			next_dc->di.lstart = di.lstart;
916 			next_dc->di.len += di.len;
917 			next_dc->di.start = di.start;
918 			__relocate_discard_cmd(dcc, next_dc);
919 			if (tdc)
920 				__remove_discard_cmd(sbi, tdc);
921 
922 			merged = true;
923 		}
924 
925 		if (!merged)
926 			__insert_discard_tree(sbi, bdev, di.lstart, di.start,
927 							di.len, NULL, NULL);
928  next:
929 		prev_dc = next_dc;
930 		if (!prev_dc)
931 			break;
932 
933 		node = rb_next(&prev_dc->rb_node);
934 		next_dc = rb_entry_safe(node, struct discard_cmd, rb_node);
935 	}
936 
937 	mutex_unlock(&dcc->cmd_lock);
938 }
939 
940 static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
941 		struct block_device *bdev, block_t blkstart, block_t blklen)
942 {
943 	block_t lblkstart = blkstart;
944 
945 	trace_f2fs_issue_discard(bdev, blkstart, blklen);
946 
947 	if (sbi->s_ndevs) {
948 		int devi = f2fs_target_device_index(sbi, blkstart);
949 
950 		blkstart -= FDEV(devi).start_blk;
951 	}
952 	__update_discard_tree_range(sbi, bdev, lblkstart, blkstart, blklen);
953 	wake_up(&SM_I(sbi)->dcc_info->discard_wait_queue);
954 	return 0;
955 }
956 
957 /* This should be covered by global mutex, &sit_i->sentry_lock */
958 void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
959 {
960 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
961 	struct discard_cmd *dc;
962 
963 	mutex_lock(&dcc->cmd_lock);
964 
965 	dc = (struct discard_cmd *)__lookup_rb_tree(&dcc->root, NULL, blkaddr);
966 	if (dc) {
967 		if (dc->state != D_PREP)
968 			wait_for_completion_io(&dc->wait);
969 		__punch_discard_cmd(sbi, dc, blkaddr);
970 	}
971 
972 	mutex_unlock(&dcc->cmd_lock);
973 }
974 
975 /* This comes from f2fs_put_super */
976 void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
977 {
978 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
979 	struct list_head *pend_list;
980 	struct list_head *wait_list = &(dcc->wait_list);
981 	struct discard_cmd *dc, *tmp;
982 	struct blk_plug plug;
983 	int i;
984 
985 	mutex_lock(&dcc->cmd_lock);
986 
987 	blk_start_plug(&plug);
988 	for (i = 0; i < MAX_PLIST_NUM; i++) {
989 		pend_list = &dcc->pend_list[i];
990 		list_for_each_entry_safe(dc, tmp, pend_list, list)
991 			__submit_discard_cmd(sbi, dc);
992 	}
993 	blk_finish_plug(&plug);
994 
995 	list_for_each_entry_safe(dc, tmp, wait_list, list) {
996 		wait_for_completion_io(&dc->wait);
997 		__remove_discard_cmd(sbi, dc);
998 	}
999 
1000 	mutex_unlock(&dcc->cmd_lock);
1001 }
1002 
1003 static int issue_discard_thread(void *data)
1004 {
1005 	struct f2fs_sb_info *sbi = data;
1006 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1007 	wait_queue_head_t *q = &dcc->discard_wait_queue;
1008 	struct list_head *pend_list;
1009 	struct list_head *wait_list = &dcc->wait_list;
1010 	struct discard_cmd *dc, *tmp;
1011 	struct blk_plug plug;
1012 	int iter = 0, i;
1013 repeat:
1014 	if (kthread_should_stop())
1015 		return 0;
1016 
1017 	mutex_lock(&dcc->cmd_lock);
1018 	blk_start_plug(&plug);
1019 	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
1020 		pend_list = &dcc->pend_list[i];
1021 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
1022 			f2fs_bug_on(sbi, dc->state != D_PREP);
1023 
1024 			if (is_idle(sbi))
1025 				__submit_discard_cmd(sbi, dc);
1026 
1027 			if (iter++ > DISCARD_ISSUE_RATE)
1028 				goto next_step;
1029 		}
1030 	}
1031 next_step:
1032 	blk_finish_plug(&plug);
1033 
1034 	list_for_each_entry_safe(dc, tmp, wait_list, list) {
1035 		if (dc->state == D_DONE) {
1036 			wait_for_completion_io(&dc->wait);
1037 			__remove_discard_cmd(sbi, dc);
1038 		}
1039 	}
1040 	mutex_unlock(&dcc->cmd_lock);
1041 
1042 	iter = 0;
1043 	congestion_wait(BLK_RW_SYNC, HZ/50);
1044 
1045 	wait_event_interruptible(*q, kthread_should_stop() ||
1046 				atomic_read(&dcc->discard_cmd_cnt));
1047 	goto repeat;
1048 }
1049 
1050 #ifdef CONFIG_BLK_DEV_ZONED
1051 static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
1052 		struct block_device *bdev, block_t blkstart, block_t blklen)
1053 {
1054 	sector_t sector, nr_sects;
1055 	block_t lblkstart = blkstart;
1056 	int devi = 0;
1057 
1058 	if (sbi->s_ndevs) {
1059 		devi = f2fs_target_device_index(sbi, blkstart);
1060 		blkstart -= FDEV(devi).start_blk;
1061 	}
1062 
1063 	/*
1064 	 * We need to know the type of the zone: for conventional zones,
1065 	 * use regular discard if the drive supports it. For sequential
1066 	 * zones, reset the zone write pointer.
1067 	 */
1068 	switch (get_blkz_type(sbi, bdev, blkstart)) {
1069 
1070 	case BLK_ZONE_TYPE_CONVENTIONAL:
1071 		if (!blk_queue_discard(bdev_get_queue(bdev)))
1072 			return 0;
1073 		return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
1074 	case BLK_ZONE_TYPE_SEQWRITE_REQ:
1075 	case BLK_ZONE_TYPE_SEQWRITE_PREF:
1076 		sector = SECTOR_FROM_BLOCK(blkstart);
1077 		nr_sects = SECTOR_FROM_BLOCK(blklen);
1078 
1079 		if (sector & (bdev_zone_sectors(bdev) - 1) ||
1080 				nr_sects != bdev_zone_sectors(bdev)) {
1081 			f2fs_msg(sbi->sb, KERN_INFO,
1082 				"(%d) %s: Unaligned discard attempted (block %x + %x)",
1083 				devi, sbi->s_ndevs ? FDEV(devi).path: "",
1084 				blkstart, blklen);
1085 			return -EIO;
1086 		}
1087 		trace_f2fs_issue_reset_zone(bdev, blkstart);
1088 		return blkdev_reset_zones(bdev, sector,
1089 					  nr_sects, GFP_NOFS);
1090 	default:
1091 		/* Unknown zone type: broken device ? */
1092 		return -EIO;
1093 	}
1094 }
1095 #endif
1096 
1097 static int __issue_discard_async(struct f2fs_sb_info *sbi,
1098 		struct block_device *bdev, block_t blkstart, block_t blklen)
1099 {
1100 #ifdef CONFIG_BLK_DEV_ZONED
1101 	if (f2fs_sb_mounted_blkzoned(sbi->sb) &&
1102 				bdev_zoned_model(bdev) != BLK_ZONED_NONE)
1103 		return __f2fs_issue_discard_zone(sbi, bdev, blkstart, blklen);
1104 #endif
1105 	return __queue_discard_cmd(sbi, bdev, blkstart, blklen);
1106 }
1107 
1108 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
1109 				block_t blkstart, block_t blklen)
1110 {
1111 	sector_t start = blkstart, len = 0;
1112 	struct block_device *bdev;
1113 	struct seg_entry *se;
1114 	unsigned int offset;
1115 	block_t i;
1116 	int err = 0;
1117 
1118 	bdev = f2fs_target_device(sbi, blkstart, NULL);
1119 
1120 	for (i = blkstart; i < blkstart + blklen; i++, len++) {
1121 		if (i != start) {
1122 			struct block_device *bdev2 =
1123 				f2fs_target_device(sbi, i, NULL);
1124 
1125 			if (bdev2 != bdev) {
1126 				err = __issue_discard_async(sbi, bdev,
1127 						start, len);
1128 				if (err)
1129 					return err;
1130 				bdev = bdev2;
1131 				start = i;
1132 				len = 0;
1133 			}
1134 		}
1135 
1136 		se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
1137 		offset = GET_BLKOFF_FROM_SEG0(sbi, i);
1138 
1139 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
1140 			sbi->discard_blks--;
1141 	}
1142 
1143 	if (len)
1144 		err = __issue_discard_async(sbi, bdev, start, len);
1145 	return err;
1146 }
1147 
1148 static bool add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc,
1149 							bool check_only)
1150 {
1151 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1152 	int max_blocks = sbi->blocks_per_seg;
1153 	struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
1154 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1155 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1156 	unsigned long *discard_map = (unsigned long *)se->discard_map;
1157 	unsigned long *dmap = SIT_I(sbi)->tmp_map;
1158 	unsigned int start = 0, end = -1;
1159 	bool force = (cpc->reason == CP_DISCARD);
1160 	struct discard_entry *de = NULL;
1161 	struct list_head *head = &SM_I(sbi)->dcc_info->entry_list;
1162 	int i;
1163 
1164 	if (se->valid_blocks == max_blocks || !f2fs_discard_en(sbi))
1165 		return false;
1166 
1167 	if (!force) {
1168 		if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
1169 			SM_I(sbi)->dcc_info->nr_discards >=
1170 				SM_I(sbi)->dcc_info->max_discards)
1171 			return false;
1172 	}
1173 
1174 	/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
1175 	for (i = 0; i < entries; i++)
1176 		dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
1177 				(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
1178 
1179 	while (force || SM_I(sbi)->dcc_info->nr_discards <=
1180 				SM_I(sbi)->dcc_info->max_discards) {
1181 		start = __find_rev_next_bit(dmap, max_blocks, end + 1);
1182 		if (start >= max_blocks)
1183 			break;
1184 
1185 		end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
1186 		if (force && start && end != max_blocks
1187 					&& (end - start) < cpc->trim_minlen)
1188 			continue;
1189 
1190 		if (check_only)
1191 			return true;
1192 
1193 		if (!de) {
1194 			de = f2fs_kmem_cache_alloc(discard_entry_slab,
1195 								GFP_F2FS_ZERO);
1196 			de->start_blkaddr = START_BLOCK(sbi, cpc->trim_start);
1197 			list_add_tail(&de->list, head);
1198 		}
1199 
1200 		for (i = start; i < end; i++)
1201 			__set_bit_le(i, (void *)de->discard_map);
1202 
1203 		SM_I(sbi)->dcc_info->nr_discards += end - start;
1204 	}
1205 	return false;
1206 }
1207 
1208 void release_discard_addrs(struct f2fs_sb_info *sbi)
1209 {
1210 	struct list_head *head = &(SM_I(sbi)->dcc_info->entry_list);
1211 	struct discard_entry *entry, *this;
1212 
1213 	/* drop caches */
1214 	list_for_each_entry_safe(entry, this, head, list) {
1215 		list_del(&entry->list);
1216 		kmem_cache_free(discard_entry_slab, entry);
1217 	}
1218 }
1219 
1220 /*
1221  * Should call clear_prefree_segments after checkpoint is done.
1222  */
1223 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
1224 {
1225 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1226 	unsigned int segno;
1227 
1228 	mutex_lock(&dirty_i->seglist_lock);
1229 	for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
1230 		__set_test_and_free(sbi, segno);
1231 	mutex_unlock(&dirty_i->seglist_lock);
1232 }
1233 
1234 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1235 {
1236 	struct list_head *head = &(SM_I(sbi)->dcc_info->entry_list);
1237 	struct discard_entry *entry, *this;
1238 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1239 	unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
1240 	unsigned int start = 0, end = -1;
1241 	unsigned int secno, start_segno;
1242 	bool force = (cpc->reason == CP_DISCARD);
1243 
1244 	mutex_lock(&dirty_i->seglist_lock);
1245 
1246 	while (1) {
1247 		int i;
1248 		start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
1249 		if (start >= MAIN_SEGS(sbi))
1250 			break;
1251 		end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
1252 								start + 1);
1253 
1254 		for (i = start; i < end; i++)
1255 			clear_bit(i, prefree_map);
1256 
1257 		dirty_i->nr_dirty[PRE] -= end - start;
1258 
1259 		if (!test_opt(sbi, DISCARD))
1260 			continue;
1261 
1262 		if (force && start >= cpc->trim_start &&
1263 					(end - 1) <= cpc->trim_end)
1264 				continue;
1265 
1266 		if (!test_opt(sbi, LFS) || sbi->segs_per_sec == 1) {
1267 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
1268 				(end - start) << sbi->log_blocks_per_seg);
1269 			continue;
1270 		}
1271 next:
1272 		secno = GET_SEC_FROM_SEG(sbi, start);
1273 		start_segno = GET_SEG_FROM_SEC(sbi, secno);
1274 		if (!IS_CURSEC(sbi, secno) &&
1275 			!get_valid_blocks(sbi, start, true))
1276 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start_segno),
1277 				sbi->segs_per_sec << sbi->log_blocks_per_seg);
1278 
1279 		start = start_segno + sbi->segs_per_sec;
1280 		if (start < end)
1281 			goto next;
1282 		else
1283 			end = start - 1;
1284 	}
1285 	mutex_unlock(&dirty_i->seglist_lock);
1286 
1287 	/* send small discards */
1288 	list_for_each_entry_safe(entry, this, head, list) {
1289 		unsigned int cur_pos = 0, next_pos, len, total_len = 0;
1290 		bool is_valid = test_bit_le(0, entry->discard_map);
1291 
1292 find_next:
1293 		if (is_valid) {
1294 			next_pos = find_next_zero_bit_le(entry->discard_map,
1295 					sbi->blocks_per_seg, cur_pos);
1296 			len = next_pos - cur_pos;
1297 
1298 			if (force && len < cpc->trim_minlen)
1299 				goto skip;
1300 
1301 			f2fs_issue_discard(sbi, entry->start_blkaddr + cur_pos,
1302 									len);
1303 			cpc->trimmed += len;
1304 			total_len += len;
1305 		} else {
1306 			next_pos = find_next_bit_le(entry->discard_map,
1307 					sbi->blocks_per_seg, cur_pos);
1308 		}
1309 skip:
1310 		cur_pos = next_pos;
1311 		is_valid = !is_valid;
1312 
1313 		if (cur_pos < sbi->blocks_per_seg)
1314 			goto find_next;
1315 
1316 		list_del(&entry->list);
1317 		SM_I(sbi)->dcc_info->nr_discards -= total_len;
1318 		kmem_cache_free(discard_entry_slab, entry);
1319 	}
1320 }
1321 
1322 static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
1323 {
1324 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1325 	struct discard_cmd_control *dcc;
1326 	int err = 0, i;
1327 
1328 	if (SM_I(sbi)->dcc_info) {
1329 		dcc = SM_I(sbi)->dcc_info;
1330 		goto init_thread;
1331 	}
1332 
1333 	dcc = kzalloc(sizeof(struct discard_cmd_control), GFP_KERNEL);
1334 	if (!dcc)
1335 		return -ENOMEM;
1336 
1337 	INIT_LIST_HEAD(&dcc->entry_list);
1338 	for (i = 0; i < MAX_PLIST_NUM; i++)
1339 		INIT_LIST_HEAD(&dcc->pend_list[i]);
1340 	INIT_LIST_HEAD(&dcc->wait_list);
1341 	mutex_init(&dcc->cmd_lock);
1342 	atomic_set(&dcc->issued_discard, 0);
1343 	atomic_set(&dcc->issing_discard, 0);
1344 	atomic_set(&dcc->discard_cmd_cnt, 0);
1345 	dcc->nr_discards = 0;
1346 	dcc->max_discards = 0;
1347 	dcc->root = RB_ROOT;
1348 
1349 	init_waitqueue_head(&dcc->discard_wait_queue);
1350 	SM_I(sbi)->dcc_info = dcc;
1351 init_thread:
1352 	dcc->f2fs_issue_discard = kthread_run(issue_discard_thread, sbi,
1353 				"f2fs_discard-%u:%u", MAJOR(dev), MINOR(dev));
1354 	if (IS_ERR(dcc->f2fs_issue_discard)) {
1355 		err = PTR_ERR(dcc->f2fs_issue_discard);
1356 		kfree(dcc);
1357 		SM_I(sbi)->dcc_info = NULL;
1358 		return err;
1359 	}
1360 
1361 	return err;
1362 }
1363 
1364 static void destroy_discard_cmd_control(struct f2fs_sb_info *sbi)
1365 {
1366 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1367 
1368 	if (!dcc)
1369 		return;
1370 
1371 	if (dcc->f2fs_issue_discard) {
1372 		struct task_struct *discard_thread = dcc->f2fs_issue_discard;
1373 
1374 		dcc->f2fs_issue_discard = NULL;
1375 		kthread_stop(discard_thread);
1376 	}
1377 
1378 	kfree(dcc);
1379 	SM_I(sbi)->dcc_info = NULL;
1380 }
1381 
1382 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
1383 {
1384 	struct sit_info *sit_i = SIT_I(sbi);
1385 
1386 	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
1387 		sit_i->dirty_sentries++;
1388 		return false;
1389 	}
1390 
1391 	return true;
1392 }
1393 
1394 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
1395 					unsigned int segno, int modified)
1396 {
1397 	struct seg_entry *se = get_seg_entry(sbi, segno);
1398 	se->type = type;
1399 	if (modified)
1400 		__mark_sit_entry_dirty(sbi, segno);
1401 }
1402 
1403 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
1404 {
1405 	struct seg_entry *se;
1406 	unsigned int segno, offset;
1407 	long int new_vblocks;
1408 
1409 	segno = GET_SEGNO(sbi, blkaddr);
1410 
1411 	se = get_seg_entry(sbi, segno);
1412 	new_vblocks = se->valid_blocks + del;
1413 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1414 
1415 	f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
1416 				(new_vblocks > sbi->blocks_per_seg)));
1417 
1418 	se->valid_blocks = new_vblocks;
1419 	se->mtime = get_mtime(sbi);
1420 	SIT_I(sbi)->max_mtime = se->mtime;
1421 
1422 	/* Update valid block bitmap */
1423 	if (del > 0) {
1424 		if (f2fs_test_and_set_bit(offset, se->cur_valid_map)) {
1425 #ifdef CONFIG_F2FS_CHECK_FS
1426 			if (f2fs_test_and_set_bit(offset,
1427 						se->cur_valid_map_mir))
1428 				f2fs_bug_on(sbi, 1);
1429 			else
1430 				WARN_ON(1);
1431 #else
1432 			f2fs_bug_on(sbi, 1);
1433 #endif
1434 		}
1435 		if (f2fs_discard_en(sbi) &&
1436 			!f2fs_test_and_set_bit(offset, se->discard_map))
1437 			sbi->discard_blks--;
1438 
1439 		/* don't overwrite by SSR to keep node chain */
1440 		if (se->type == CURSEG_WARM_NODE) {
1441 			if (!f2fs_test_and_set_bit(offset, se->ckpt_valid_map))
1442 				se->ckpt_valid_blocks++;
1443 		}
1444 	} else {
1445 		if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map)) {
1446 #ifdef CONFIG_F2FS_CHECK_FS
1447 			if (!f2fs_test_and_clear_bit(offset,
1448 						se->cur_valid_map_mir))
1449 				f2fs_bug_on(sbi, 1);
1450 			else
1451 				WARN_ON(1);
1452 #else
1453 			f2fs_bug_on(sbi, 1);
1454 #endif
1455 		}
1456 		if (f2fs_discard_en(sbi) &&
1457 			f2fs_test_and_clear_bit(offset, se->discard_map))
1458 			sbi->discard_blks++;
1459 	}
1460 	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
1461 		se->ckpt_valid_blocks += del;
1462 
1463 	__mark_sit_entry_dirty(sbi, segno);
1464 
1465 	/* update total number of valid blocks to be written in ckpt area */
1466 	SIT_I(sbi)->written_valid_blocks += del;
1467 
1468 	if (sbi->segs_per_sec > 1)
1469 		get_sec_entry(sbi, segno)->valid_blocks += del;
1470 }
1471 
1472 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new)
1473 {
1474 	update_sit_entry(sbi, new, 1);
1475 	if (GET_SEGNO(sbi, old) != NULL_SEGNO)
1476 		update_sit_entry(sbi, old, -1);
1477 
1478 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old));
1479 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new));
1480 }
1481 
1482 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
1483 {
1484 	unsigned int segno = GET_SEGNO(sbi, addr);
1485 	struct sit_info *sit_i = SIT_I(sbi);
1486 
1487 	f2fs_bug_on(sbi, addr == NULL_ADDR);
1488 	if (addr == NEW_ADDR)
1489 		return;
1490 
1491 	/* add it into sit main buffer */
1492 	mutex_lock(&sit_i->sentry_lock);
1493 
1494 	update_sit_entry(sbi, addr, -1);
1495 
1496 	/* add it into dirty seglist */
1497 	locate_dirty_segment(sbi, segno);
1498 
1499 	mutex_unlock(&sit_i->sentry_lock);
1500 }
1501 
1502 bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
1503 {
1504 	struct sit_info *sit_i = SIT_I(sbi);
1505 	unsigned int segno, offset;
1506 	struct seg_entry *se;
1507 	bool is_cp = false;
1508 
1509 	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR)
1510 		return true;
1511 
1512 	mutex_lock(&sit_i->sentry_lock);
1513 
1514 	segno = GET_SEGNO(sbi, blkaddr);
1515 	se = get_seg_entry(sbi, segno);
1516 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1517 
1518 	if (f2fs_test_bit(offset, se->ckpt_valid_map))
1519 		is_cp = true;
1520 
1521 	mutex_unlock(&sit_i->sentry_lock);
1522 
1523 	return is_cp;
1524 }
1525 
1526 /*
1527  * This function should be resided under the curseg_mutex lock
1528  */
1529 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
1530 					struct f2fs_summary *sum)
1531 {
1532 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1533 	void *addr = curseg->sum_blk;
1534 	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
1535 	memcpy(addr, sum, sizeof(struct f2fs_summary));
1536 }
1537 
1538 /*
1539  * Calculate the number of current summary pages for writing
1540  */
1541 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
1542 {
1543 	int valid_sum_count = 0;
1544 	int i, sum_in_page;
1545 
1546 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1547 		if (sbi->ckpt->alloc_type[i] == SSR)
1548 			valid_sum_count += sbi->blocks_per_seg;
1549 		else {
1550 			if (for_ra)
1551 				valid_sum_count += le16_to_cpu(
1552 					F2FS_CKPT(sbi)->cur_data_blkoff[i]);
1553 			else
1554 				valid_sum_count += curseg_blkoff(sbi, i);
1555 		}
1556 	}
1557 
1558 	sum_in_page = (PAGE_SIZE - 2 * SUM_JOURNAL_SIZE -
1559 			SUM_FOOTER_SIZE) / SUMMARY_SIZE;
1560 	if (valid_sum_count <= sum_in_page)
1561 		return 1;
1562 	else if ((valid_sum_count - sum_in_page) <=
1563 		(PAGE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
1564 		return 2;
1565 	return 3;
1566 }
1567 
1568 /*
1569  * Caller should put this summary page
1570  */
1571 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
1572 {
1573 	return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
1574 }
1575 
1576 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr)
1577 {
1578 	struct page *page = grab_meta_page(sbi, blk_addr);
1579 	void *dst = page_address(page);
1580 
1581 	if (src)
1582 		memcpy(dst, src, PAGE_SIZE);
1583 	else
1584 		memset(dst, 0, PAGE_SIZE);
1585 	set_page_dirty(page);
1586 	f2fs_put_page(page, 1);
1587 }
1588 
1589 static void write_sum_page(struct f2fs_sb_info *sbi,
1590 			struct f2fs_summary_block *sum_blk, block_t blk_addr)
1591 {
1592 	update_meta_page(sbi, (void *)sum_blk, blk_addr);
1593 }
1594 
1595 static void write_current_sum_page(struct f2fs_sb_info *sbi,
1596 						int type, block_t blk_addr)
1597 {
1598 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1599 	struct page *page = grab_meta_page(sbi, blk_addr);
1600 	struct f2fs_summary_block *src = curseg->sum_blk;
1601 	struct f2fs_summary_block *dst;
1602 
1603 	dst = (struct f2fs_summary_block *)page_address(page);
1604 
1605 	mutex_lock(&curseg->curseg_mutex);
1606 
1607 	down_read(&curseg->journal_rwsem);
1608 	memcpy(&dst->journal, curseg->journal, SUM_JOURNAL_SIZE);
1609 	up_read(&curseg->journal_rwsem);
1610 
1611 	memcpy(dst->entries, src->entries, SUM_ENTRY_SIZE);
1612 	memcpy(&dst->footer, &src->footer, SUM_FOOTER_SIZE);
1613 
1614 	mutex_unlock(&curseg->curseg_mutex);
1615 
1616 	set_page_dirty(page);
1617 	f2fs_put_page(page, 1);
1618 }
1619 
1620 /*
1621  * Find a new segment from the free segments bitmap to right order
1622  * This function should be returned with success, otherwise BUG
1623  */
1624 static void get_new_segment(struct f2fs_sb_info *sbi,
1625 			unsigned int *newseg, bool new_sec, int dir)
1626 {
1627 	struct free_segmap_info *free_i = FREE_I(sbi);
1628 	unsigned int segno, secno, zoneno;
1629 	unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
1630 	unsigned int hint = GET_SEC_FROM_SEG(sbi, *newseg);
1631 	unsigned int old_zoneno = GET_ZONE_FROM_SEG(sbi, *newseg);
1632 	unsigned int left_start = hint;
1633 	bool init = true;
1634 	int go_left = 0;
1635 	int i;
1636 
1637 	spin_lock(&free_i->segmap_lock);
1638 
1639 	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
1640 		segno = find_next_zero_bit(free_i->free_segmap,
1641 			GET_SEG_FROM_SEC(sbi, hint + 1), *newseg + 1);
1642 		if (segno < GET_SEG_FROM_SEC(sbi, hint + 1))
1643 			goto got_it;
1644 	}
1645 find_other_zone:
1646 	secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
1647 	if (secno >= MAIN_SECS(sbi)) {
1648 		if (dir == ALLOC_RIGHT) {
1649 			secno = find_next_zero_bit(free_i->free_secmap,
1650 							MAIN_SECS(sbi), 0);
1651 			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
1652 		} else {
1653 			go_left = 1;
1654 			left_start = hint - 1;
1655 		}
1656 	}
1657 	if (go_left == 0)
1658 		goto skip_left;
1659 
1660 	while (test_bit(left_start, free_i->free_secmap)) {
1661 		if (left_start > 0) {
1662 			left_start--;
1663 			continue;
1664 		}
1665 		left_start = find_next_zero_bit(free_i->free_secmap,
1666 							MAIN_SECS(sbi), 0);
1667 		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
1668 		break;
1669 	}
1670 	secno = left_start;
1671 skip_left:
1672 	hint = secno;
1673 	segno = GET_SEG_FROM_SEC(sbi, secno);
1674 	zoneno = GET_ZONE_FROM_SEC(sbi, secno);
1675 
1676 	/* give up on finding another zone */
1677 	if (!init)
1678 		goto got_it;
1679 	if (sbi->secs_per_zone == 1)
1680 		goto got_it;
1681 	if (zoneno == old_zoneno)
1682 		goto got_it;
1683 	if (dir == ALLOC_LEFT) {
1684 		if (!go_left && zoneno + 1 >= total_zones)
1685 			goto got_it;
1686 		if (go_left && zoneno == 0)
1687 			goto got_it;
1688 	}
1689 	for (i = 0; i < NR_CURSEG_TYPE; i++)
1690 		if (CURSEG_I(sbi, i)->zone == zoneno)
1691 			break;
1692 
1693 	if (i < NR_CURSEG_TYPE) {
1694 		/* zone is in user, try another */
1695 		if (go_left)
1696 			hint = zoneno * sbi->secs_per_zone - 1;
1697 		else if (zoneno + 1 >= total_zones)
1698 			hint = 0;
1699 		else
1700 			hint = (zoneno + 1) * sbi->secs_per_zone;
1701 		init = false;
1702 		goto find_other_zone;
1703 	}
1704 got_it:
1705 	/* set it as dirty segment in free segmap */
1706 	f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
1707 	__set_inuse(sbi, segno);
1708 	*newseg = segno;
1709 	spin_unlock(&free_i->segmap_lock);
1710 }
1711 
1712 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
1713 {
1714 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1715 	struct summary_footer *sum_footer;
1716 
1717 	curseg->segno = curseg->next_segno;
1718 	curseg->zone = GET_ZONE_FROM_SEG(sbi, curseg->segno);
1719 	curseg->next_blkoff = 0;
1720 	curseg->next_segno = NULL_SEGNO;
1721 
1722 	sum_footer = &(curseg->sum_blk->footer);
1723 	memset(sum_footer, 0, sizeof(struct summary_footer));
1724 	if (IS_DATASEG(type))
1725 		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
1726 	if (IS_NODESEG(type))
1727 		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
1728 	__set_sit_entry_type(sbi, type, curseg->segno, modified);
1729 }
1730 
1731 static unsigned int __get_next_segno(struct f2fs_sb_info *sbi, int type)
1732 {
1733 	if (type == CURSEG_HOT_DATA || IS_NODESEG(type))
1734 		return 0;
1735 
1736 	return CURSEG_I(sbi, type)->segno;
1737 }
1738 
1739 /*
1740  * Allocate a current working segment.
1741  * This function always allocates a free segment in LFS manner.
1742  */
1743 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
1744 {
1745 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1746 	unsigned int segno = curseg->segno;
1747 	int dir = ALLOC_LEFT;
1748 
1749 	write_sum_page(sbi, curseg->sum_blk,
1750 				GET_SUM_BLOCK(sbi, segno));
1751 	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
1752 		dir = ALLOC_RIGHT;
1753 
1754 	if (test_opt(sbi, NOHEAP))
1755 		dir = ALLOC_RIGHT;
1756 
1757 	segno = __get_next_segno(sbi, type);
1758 	get_new_segment(sbi, &segno, new_sec, dir);
1759 	curseg->next_segno = segno;
1760 	reset_curseg(sbi, type, 1);
1761 	curseg->alloc_type = LFS;
1762 }
1763 
1764 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
1765 			struct curseg_info *seg, block_t start)
1766 {
1767 	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
1768 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1769 	unsigned long *target_map = SIT_I(sbi)->tmp_map;
1770 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1771 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1772 	int i, pos;
1773 
1774 	for (i = 0; i < entries; i++)
1775 		target_map[i] = ckpt_map[i] | cur_map[i];
1776 
1777 	pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
1778 
1779 	seg->next_blkoff = pos;
1780 }
1781 
1782 /*
1783  * If a segment is written by LFS manner, next block offset is just obtained
1784  * by increasing the current block offset. However, if a segment is written by
1785  * SSR manner, next block offset obtained by calling __next_free_blkoff
1786  */
1787 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
1788 				struct curseg_info *seg)
1789 {
1790 	if (seg->alloc_type == SSR)
1791 		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
1792 	else
1793 		seg->next_blkoff++;
1794 }
1795 
1796 /*
1797  * This function always allocates a used segment(from dirty seglist) by SSR
1798  * manner, so it should recover the existing segment information of valid blocks
1799  */
1800 static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
1801 {
1802 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1803 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1804 	unsigned int new_segno = curseg->next_segno;
1805 	struct f2fs_summary_block *sum_node;
1806 	struct page *sum_page;
1807 
1808 	write_sum_page(sbi, curseg->sum_blk,
1809 				GET_SUM_BLOCK(sbi, curseg->segno));
1810 	__set_test_and_inuse(sbi, new_segno);
1811 
1812 	mutex_lock(&dirty_i->seglist_lock);
1813 	__remove_dirty_segment(sbi, new_segno, PRE);
1814 	__remove_dirty_segment(sbi, new_segno, DIRTY);
1815 	mutex_unlock(&dirty_i->seglist_lock);
1816 
1817 	reset_curseg(sbi, type, 1);
1818 	curseg->alloc_type = SSR;
1819 	__next_free_blkoff(sbi, curseg, 0);
1820 
1821 	if (reuse) {
1822 		sum_page = get_sum_page(sbi, new_segno);
1823 		sum_node = (struct f2fs_summary_block *)page_address(sum_page);
1824 		memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
1825 		f2fs_put_page(sum_page, 1);
1826 	}
1827 }
1828 
1829 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
1830 {
1831 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1832 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
1833 	int i, cnt;
1834 	bool reversed = false;
1835 
1836 	/* need_SSR() already forces to do this */
1837 	if (v_ops->get_victim(sbi, &(curseg)->next_segno, BG_GC, type, SSR))
1838 		return 1;
1839 
1840 	/* For node segments, let's do SSR more intensively */
1841 	if (IS_NODESEG(type)) {
1842 		if (type >= CURSEG_WARM_NODE) {
1843 			reversed = true;
1844 			i = CURSEG_COLD_NODE;
1845 		} else {
1846 			i = CURSEG_HOT_NODE;
1847 		}
1848 		cnt = NR_CURSEG_NODE_TYPE;
1849 	} else {
1850 		if (type >= CURSEG_WARM_DATA) {
1851 			reversed = true;
1852 			i = CURSEG_COLD_DATA;
1853 		} else {
1854 			i = CURSEG_HOT_DATA;
1855 		}
1856 		cnt = NR_CURSEG_DATA_TYPE;
1857 	}
1858 
1859 	for (; cnt-- > 0; reversed ? i-- : i++) {
1860 		if (i == type)
1861 			continue;
1862 		if (v_ops->get_victim(sbi, &(curseg)->next_segno,
1863 						BG_GC, i, SSR))
1864 			return 1;
1865 	}
1866 	return 0;
1867 }
1868 
1869 /*
1870  * flush out current segment and replace it with new segment
1871  * This function should be returned with success, otherwise BUG
1872  */
1873 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
1874 						int type, bool force)
1875 {
1876 	if (force)
1877 		new_curseg(sbi, type, true);
1878 	else if (!is_set_ckpt_flags(sbi, CP_CRC_RECOVERY_FLAG) &&
1879 					type == CURSEG_WARM_NODE)
1880 		new_curseg(sbi, type, false);
1881 	else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
1882 		change_curseg(sbi, type, true);
1883 	else
1884 		new_curseg(sbi, type, false);
1885 
1886 	stat_inc_seg_type(sbi, CURSEG_I(sbi, type));
1887 }
1888 
1889 void allocate_new_segments(struct f2fs_sb_info *sbi)
1890 {
1891 	struct curseg_info *curseg;
1892 	unsigned int old_segno;
1893 	int i;
1894 
1895 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1896 		curseg = CURSEG_I(sbi, i);
1897 		old_segno = curseg->segno;
1898 		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
1899 		locate_dirty_segment(sbi, old_segno);
1900 	}
1901 }
1902 
1903 static const struct segment_allocation default_salloc_ops = {
1904 	.allocate_segment = allocate_segment_by_default,
1905 };
1906 
1907 bool exist_trim_candidates(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1908 {
1909 	__u64 trim_start = cpc->trim_start;
1910 	bool has_candidate = false;
1911 
1912 	mutex_lock(&SIT_I(sbi)->sentry_lock);
1913 	for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++) {
1914 		if (add_discard_addrs(sbi, cpc, true)) {
1915 			has_candidate = true;
1916 			break;
1917 		}
1918 	}
1919 	mutex_unlock(&SIT_I(sbi)->sentry_lock);
1920 
1921 	cpc->trim_start = trim_start;
1922 	return has_candidate;
1923 }
1924 
1925 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
1926 {
1927 	__u64 start = F2FS_BYTES_TO_BLK(range->start);
1928 	__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
1929 	unsigned int start_segno, end_segno;
1930 	struct cp_control cpc;
1931 	int err = 0;
1932 
1933 	if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
1934 		return -EINVAL;
1935 
1936 	cpc.trimmed = 0;
1937 	if (end <= MAIN_BLKADDR(sbi))
1938 		goto out;
1939 
1940 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
1941 		f2fs_msg(sbi->sb, KERN_WARNING,
1942 			"Found FS corruption, run fsck to fix.");
1943 		goto out;
1944 	}
1945 
1946 	/* start/end segment number in main_area */
1947 	start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
1948 	end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
1949 						GET_SEGNO(sbi, end);
1950 	cpc.reason = CP_DISCARD;
1951 	cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
1952 
1953 	/* do checkpoint to issue discard commands safely */
1954 	for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
1955 		cpc.trim_start = start_segno;
1956 
1957 		if (sbi->discard_blks == 0)
1958 			break;
1959 		else if (sbi->discard_blks < BATCHED_TRIM_BLOCKS(sbi))
1960 			cpc.trim_end = end_segno;
1961 		else
1962 			cpc.trim_end = min_t(unsigned int,
1963 				rounddown(start_segno +
1964 				BATCHED_TRIM_SEGMENTS(sbi),
1965 				sbi->segs_per_sec) - 1, end_segno);
1966 
1967 		mutex_lock(&sbi->gc_mutex);
1968 		err = write_checkpoint(sbi, &cpc);
1969 		mutex_unlock(&sbi->gc_mutex);
1970 		if (err)
1971 			break;
1972 
1973 		schedule();
1974 	}
1975 out:
1976 	range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
1977 	return err;
1978 }
1979 
1980 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
1981 {
1982 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1983 	if (curseg->next_blkoff < sbi->blocks_per_seg)
1984 		return true;
1985 	return false;
1986 }
1987 
1988 static int __get_segment_type_2(struct page *page, enum page_type p_type)
1989 {
1990 	if (p_type == DATA)
1991 		return CURSEG_HOT_DATA;
1992 	else
1993 		return CURSEG_HOT_NODE;
1994 }
1995 
1996 static int __get_segment_type_4(struct page *page, enum page_type p_type)
1997 {
1998 	if (p_type == DATA) {
1999 		struct inode *inode = page->mapping->host;
2000 
2001 		if (S_ISDIR(inode->i_mode))
2002 			return CURSEG_HOT_DATA;
2003 		else
2004 			return CURSEG_COLD_DATA;
2005 	} else {
2006 		if (IS_DNODE(page) && is_cold_node(page))
2007 			return CURSEG_WARM_NODE;
2008 		else
2009 			return CURSEG_COLD_NODE;
2010 	}
2011 }
2012 
2013 static int __get_segment_type_6(struct page *page, enum page_type p_type)
2014 {
2015 	if (p_type == DATA) {
2016 		struct inode *inode = page->mapping->host;
2017 
2018 		if (is_cold_data(page) || file_is_cold(inode))
2019 			return CURSEG_COLD_DATA;
2020 		if (is_inode_flag_set(inode, FI_HOT_DATA))
2021 			return CURSEG_HOT_DATA;
2022 		return CURSEG_WARM_DATA;
2023 	} else {
2024 		if (IS_DNODE(page))
2025 			return is_cold_node(page) ? CURSEG_WARM_NODE :
2026 						CURSEG_HOT_NODE;
2027 		return CURSEG_COLD_NODE;
2028 	}
2029 }
2030 
2031 static int __get_segment_type(struct page *page, enum page_type p_type)
2032 {
2033 	switch (F2FS_P_SB(page)->active_logs) {
2034 	case 2:
2035 		return __get_segment_type_2(page, p_type);
2036 	case 4:
2037 		return __get_segment_type_4(page, p_type);
2038 	}
2039 	/* NR_CURSEG_TYPE(6) logs by default */
2040 	f2fs_bug_on(F2FS_P_SB(page),
2041 		F2FS_P_SB(page)->active_logs != NR_CURSEG_TYPE);
2042 	return __get_segment_type_6(page, p_type);
2043 }
2044 
2045 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
2046 		block_t old_blkaddr, block_t *new_blkaddr,
2047 		struct f2fs_summary *sum, int type)
2048 {
2049 	struct sit_info *sit_i = SIT_I(sbi);
2050 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2051 
2052 	mutex_lock(&curseg->curseg_mutex);
2053 	mutex_lock(&sit_i->sentry_lock);
2054 
2055 	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
2056 
2057 	f2fs_wait_discard_bio(sbi, *new_blkaddr);
2058 
2059 	/*
2060 	 * __add_sum_entry should be resided under the curseg_mutex
2061 	 * because, this function updates a summary entry in the
2062 	 * current summary block.
2063 	 */
2064 	__add_sum_entry(sbi, type, sum);
2065 
2066 	__refresh_next_blkoff(sbi, curseg);
2067 
2068 	stat_inc_block_count(sbi, curseg);
2069 
2070 	if (!__has_curseg_space(sbi, type))
2071 		sit_i->s_ops->allocate_segment(sbi, type, false);
2072 	/*
2073 	 * SIT information should be updated after segment allocation,
2074 	 * since we need to keep dirty segments precisely under SSR.
2075 	 */
2076 	refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
2077 
2078 	mutex_unlock(&sit_i->sentry_lock);
2079 
2080 	if (page && IS_NODESEG(type))
2081 		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
2082 
2083 	mutex_unlock(&curseg->curseg_mutex);
2084 }
2085 
2086 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
2087 {
2088 	int type = __get_segment_type(fio->page, fio->type);
2089 	int err;
2090 
2091 	if (fio->type == NODE || fio->type == DATA)
2092 		mutex_lock(&fio->sbi->wio_mutex[fio->type]);
2093 reallocate:
2094 	allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
2095 					&fio->new_blkaddr, sum, type);
2096 
2097 	/* writeout dirty page into bdev */
2098 	err = f2fs_submit_page_mbio(fio);
2099 	if (err == -EAGAIN) {
2100 		fio->old_blkaddr = fio->new_blkaddr;
2101 		goto reallocate;
2102 	}
2103 
2104 	if (fio->type == NODE || fio->type == DATA)
2105 		mutex_unlock(&fio->sbi->wio_mutex[fio->type]);
2106 }
2107 
2108 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
2109 {
2110 	struct f2fs_io_info fio = {
2111 		.sbi = sbi,
2112 		.type = META,
2113 		.op = REQ_OP_WRITE,
2114 		.op_flags = REQ_SYNC | REQ_META | REQ_PRIO,
2115 		.old_blkaddr = page->index,
2116 		.new_blkaddr = page->index,
2117 		.page = page,
2118 		.encrypted_page = NULL,
2119 	};
2120 
2121 	if (unlikely(page->index >= MAIN_BLKADDR(sbi)))
2122 		fio.op_flags &= ~REQ_META;
2123 
2124 	set_page_writeback(page);
2125 	f2fs_submit_page_mbio(&fio);
2126 }
2127 
2128 void write_node_page(unsigned int nid, struct f2fs_io_info *fio)
2129 {
2130 	struct f2fs_summary sum;
2131 
2132 	set_summary(&sum, nid, 0, 0);
2133 	do_write_page(&sum, fio);
2134 }
2135 
2136 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio)
2137 {
2138 	struct f2fs_sb_info *sbi = fio->sbi;
2139 	struct f2fs_summary sum;
2140 	struct node_info ni;
2141 
2142 	f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
2143 	get_node_info(sbi, dn->nid, &ni);
2144 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
2145 	do_write_page(&sum, fio);
2146 	f2fs_update_data_blkaddr(dn, fio->new_blkaddr);
2147 }
2148 
2149 int rewrite_data_page(struct f2fs_io_info *fio)
2150 {
2151 	fio->new_blkaddr = fio->old_blkaddr;
2152 	stat_inc_inplace_blocks(fio->sbi);
2153 	return f2fs_submit_page_bio(fio);
2154 }
2155 
2156 void __f2fs_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
2157 				block_t old_blkaddr, block_t new_blkaddr,
2158 				bool recover_curseg, bool recover_newaddr)
2159 {
2160 	struct sit_info *sit_i = SIT_I(sbi);
2161 	struct curseg_info *curseg;
2162 	unsigned int segno, old_cursegno;
2163 	struct seg_entry *se;
2164 	int type;
2165 	unsigned short old_blkoff;
2166 
2167 	segno = GET_SEGNO(sbi, new_blkaddr);
2168 	se = get_seg_entry(sbi, segno);
2169 	type = se->type;
2170 
2171 	if (!recover_curseg) {
2172 		/* for recovery flow */
2173 		if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
2174 			if (old_blkaddr == NULL_ADDR)
2175 				type = CURSEG_COLD_DATA;
2176 			else
2177 				type = CURSEG_WARM_DATA;
2178 		}
2179 	} else {
2180 		if (!IS_CURSEG(sbi, segno))
2181 			type = CURSEG_WARM_DATA;
2182 	}
2183 
2184 	curseg = CURSEG_I(sbi, type);
2185 
2186 	mutex_lock(&curseg->curseg_mutex);
2187 	mutex_lock(&sit_i->sentry_lock);
2188 
2189 	old_cursegno = curseg->segno;
2190 	old_blkoff = curseg->next_blkoff;
2191 
2192 	/* change the current segment */
2193 	if (segno != curseg->segno) {
2194 		curseg->next_segno = segno;
2195 		change_curseg(sbi, type, true);
2196 	}
2197 
2198 	curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
2199 	__add_sum_entry(sbi, type, sum);
2200 
2201 	if (!recover_curseg || recover_newaddr)
2202 		update_sit_entry(sbi, new_blkaddr, 1);
2203 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
2204 		update_sit_entry(sbi, old_blkaddr, -1);
2205 
2206 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
2207 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new_blkaddr));
2208 
2209 	locate_dirty_segment(sbi, old_cursegno);
2210 
2211 	if (recover_curseg) {
2212 		if (old_cursegno != curseg->segno) {
2213 			curseg->next_segno = old_cursegno;
2214 			change_curseg(sbi, type, true);
2215 		}
2216 		curseg->next_blkoff = old_blkoff;
2217 	}
2218 
2219 	mutex_unlock(&sit_i->sentry_lock);
2220 	mutex_unlock(&curseg->curseg_mutex);
2221 }
2222 
2223 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
2224 				block_t old_addr, block_t new_addr,
2225 				unsigned char version, bool recover_curseg,
2226 				bool recover_newaddr)
2227 {
2228 	struct f2fs_summary sum;
2229 
2230 	set_summary(&sum, dn->nid, dn->ofs_in_node, version);
2231 
2232 	__f2fs_replace_block(sbi, &sum, old_addr, new_addr,
2233 					recover_curseg, recover_newaddr);
2234 
2235 	f2fs_update_data_blkaddr(dn, new_addr);
2236 }
2237 
2238 void f2fs_wait_on_page_writeback(struct page *page,
2239 				enum page_type type, bool ordered)
2240 {
2241 	if (PageWriteback(page)) {
2242 		struct f2fs_sb_info *sbi = F2FS_P_SB(page);
2243 
2244 		f2fs_submit_merged_bio_cond(sbi, page->mapping->host,
2245 						0, page->index, type, WRITE);
2246 		if (ordered)
2247 			wait_on_page_writeback(page);
2248 		else
2249 			wait_for_stable_page(page);
2250 	}
2251 }
2252 
2253 void f2fs_wait_on_encrypted_page_writeback(struct f2fs_sb_info *sbi,
2254 							block_t blkaddr)
2255 {
2256 	struct page *cpage;
2257 
2258 	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR)
2259 		return;
2260 
2261 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
2262 	if (cpage) {
2263 		f2fs_wait_on_page_writeback(cpage, DATA, true);
2264 		f2fs_put_page(cpage, 1);
2265 	}
2266 }
2267 
2268 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
2269 {
2270 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2271 	struct curseg_info *seg_i;
2272 	unsigned char *kaddr;
2273 	struct page *page;
2274 	block_t start;
2275 	int i, j, offset;
2276 
2277 	start = start_sum_block(sbi);
2278 
2279 	page = get_meta_page(sbi, start++);
2280 	kaddr = (unsigned char *)page_address(page);
2281 
2282 	/* Step 1: restore nat cache */
2283 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
2284 	memcpy(seg_i->journal, kaddr, SUM_JOURNAL_SIZE);
2285 
2286 	/* Step 2: restore sit cache */
2287 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
2288 	memcpy(seg_i->journal, kaddr + SUM_JOURNAL_SIZE, SUM_JOURNAL_SIZE);
2289 	offset = 2 * SUM_JOURNAL_SIZE;
2290 
2291 	/* Step 3: restore summary entries */
2292 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
2293 		unsigned short blk_off;
2294 		unsigned int segno;
2295 
2296 		seg_i = CURSEG_I(sbi, i);
2297 		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
2298 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
2299 		seg_i->next_segno = segno;
2300 		reset_curseg(sbi, i, 0);
2301 		seg_i->alloc_type = ckpt->alloc_type[i];
2302 		seg_i->next_blkoff = blk_off;
2303 
2304 		if (seg_i->alloc_type == SSR)
2305 			blk_off = sbi->blocks_per_seg;
2306 
2307 		for (j = 0; j < blk_off; j++) {
2308 			struct f2fs_summary *s;
2309 			s = (struct f2fs_summary *)(kaddr + offset);
2310 			seg_i->sum_blk->entries[j] = *s;
2311 			offset += SUMMARY_SIZE;
2312 			if (offset + SUMMARY_SIZE <= PAGE_SIZE -
2313 						SUM_FOOTER_SIZE)
2314 				continue;
2315 
2316 			f2fs_put_page(page, 1);
2317 			page = NULL;
2318 
2319 			page = get_meta_page(sbi, start++);
2320 			kaddr = (unsigned char *)page_address(page);
2321 			offset = 0;
2322 		}
2323 	}
2324 	f2fs_put_page(page, 1);
2325 	return 0;
2326 }
2327 
2328 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
2329 {
2330 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2331 	struct f2fs_summary_block *sum;
2332 	struct curseg_info *curseg;
2333 	struct page *new;
2334 	unsigned short blk_off;
2335 	unsigned int segno = 0;
2336 	block_t blk_addr = 0;
2337 
2338 	/* get segment number and block addr */
2339 	if (IS_DATASEG(type)) {
2340 		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
2341 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
2342 							CURSEG_HOT_DATA]);
2343 		if (__exist_node_summaries(sbi))
2344 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
2345 		else
2346 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
2347 	} else {
2348 		segno = le32_to_cpu(ckpt->cur_node_segno[type -
2349 							CURSEG_HOT_NODE]);
2350 		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
2351 							CURSEG_HOT_NODE]);
2352 		if (__exist_node_summaries(sbi))
2353 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
2354 							type - CURSEG_HOT_NODE);
2355 		else
2356 			blk_addr = GET_SUM_BLOCK(sbi, segno);
2357 	}
2358 
2359 	new = get_meta_page(sbi, blk_addr);
2360 	sum = (struct f2fs_summary_block *)page_address(new);
2361 
2362 	if (IS_NODESEG(type)) {
2363 		if (__exist_node_summaries(sbi)) {
2364 			struct f2fs_summary *ns = &sum->entries[0];
2365 			int i;
2366 			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
2367 				ns->version = 0;
2368 				ns->ofs_in_node = 0;
2369 			}
2370 		} else {
2371 			int err;
2372 
2373 			err = restore_node_summary(sbi, segno, sum);
2374 			if (err) {
2375 				f2fs_put_page(new, 1);
2376 				return err;
2377 			}
2378 		}
2379 	}
2380 
2381 	/* set uncompleted segment to curseg */
2382 	curseg = CURSEG_I(sbi, type);
2383 	mutex_lock(&curseg->curseg_mutex);
2384 
2385 	/* update journal info */
2386 	down_write(&curseg->journal_rwsem);
2387 	memcpy(curseg->journal, &sum->journal, SUM_JOURNAL_SIZE);
2388 	up_write(&curseg->journal_rwsem);
2389 
2390 	memcpy(curseg->sum_blk->entries, sum->entries, SUM_ENTRY_SIZE);
2391 	memcpy(&curseg->sum_blk->footer, &sum->footer, SUM_FOOTER_SIZE);
2392 	curseg->next_segno = segno;
2393 	reset_curseg(sbi, type, 0);
2394 	curseg->alloc_type = ckpt->alloc_type[type];
2395 	curseg->next_blkoff = blk_off;
2396 	mutex_unlock(&curseg->curseg_mutex);
2397 	f2fs_put_page(new, 1);
2398 	return 0;
2399 }
2400 
2401 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
2402 {
2403 	int type = CURSEG_HOT_DATA;
2404 	int err;
2405 
2406 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG)) {
2407 		int npages = npages_for_summary_flush(sbi, true);
2408 
2409 		if (npages >= 2)
2410 			ra_meta_pages(sbi, start_sum_block(sbi), npages,
2411 							META_CP, true);
2412 
2413 		/* restore for compacted data summary */
2414 		if (read_compacted_summaries(sbi))
2415 			return -EINVAL;
2416 		type = CURSEG_HOT_NODE;
2417 	}
2418 
2419 	if (__exist_node_summaries(sbi))
2420 		ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
2421 					NR_CURSEG_TYPE - type, META_CP, true);
2422 
2423 	for (; type <= CURSEG_COLD_NODE; type++) {
2424 		err = read_normal_summaries(sbi, type);
2425 		if (err)
2426 			return err;
2427 	}
2428 
2429 	return 0;
2430 }
2431 
2432 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
2433 {
2434 	struct page *page;
2435 	unsigned char *kaddr;
2436 	struct f2fs_summary *summary;
2437 	struct curseg_info *seg_i;
2438 	int written_size = 0;
2439 	int i, j;
2440 
2441 	page = grab_meta_page(sbi, blkaddr++);
2442 	kaddr = (unsigned char *)page_address(page);
2443 
2444 	/* Step 1: write nat cache */
2445 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
2446 	memcpy(kaddr, seg_i->journal, SUM_JOURNAL_SIZE);
2447 	written_size += SUM_JOURNAL_SIZE;
2448 
2449 	/* Step 2: write sit cache */
2450 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
2451 	memcpy(kaddr + written_size, seg_i->journal, SUM_JOURNAL_SIZE);
2452 	written_size += SUM_JOURNAL_SIZE;
2453 
2454 	/* Step 3: write summary entries */
2455 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
2456 		unsigned short blkoff;
2457 		seg_i = CURSEG_I(sbi, i);
2458 		if (sbi->ckpt->alloc_type[i] == SSR)
2459 			blkoff = sbi->blocks_per_seg;
2460 		else
2461 			blkoff = curseg_blkoff(sbi, i);
2462 
2463 		for (j = 0; j < blkoff; j++) {
2464 			if (!page) {
2465 				page = grab_meta_page(sbi, blkaddr++);
2466 				kaddr = (unsigned char *)page_address(page);
2467 				written_size = 0;
2468 			}
2469 			summary = (struct f2fs_summary *)(kaddr + written_size);
2470 			*summary = seg_i->sum_blk->entries[j];
2471 			written_size += SUMMARY_SIZE;
2472 
2473 			if (written_size + SUMMARY_SIZE <= PAGE_SIZE -
2474 							SUM_FOOTER_SIZE)
2475 				continue;
2476 
2477 			set_page_dirty(page);
2478 			f2fs_put_page(page, 1);
2479 			page = NULL;
2480 		}
2481 	}
2482 	if (page) {
2483 		set_page_dirty(page);
2484 		f2fs_put_page(page, 1);
2485 	}
2486 }
2487 
2488 static void write_normal_summaries(struct f2fs_sb_info *sbi,
2489 					block_t blkaddr, int type)
2490 {
2491 	int i, end;
2492 	if (IS_DATASEG(type))
2493 		end = type + NR_CURSEG_DATA_TYPE;
2494 	else
2495 		end = type + NR_CURSEG_NODE_TYPE;
2496 
2497 	for (i = type; i < end; i++)
2498 		write_current_sum_page(sbi, i, blkaddr + (i - type));
2499 }
2500 
2501 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
2502 {
2503 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG))
2504 		write_compacted_summaries(sbi, start_blk);
2505 	else
2506 		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
2507 }
2508 
2509 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
2510 {
2511 	write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
2512 }
2513 
2514 int lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
2515 					unsigned int val, int alloc)
2516 {
2517 	int i;
2518 
2519 	if (type == NAT_JOURNAL) {
2520 		for (i = 0; i < nats_in_cursum(journal); i++) {
2521 			if (le32_to_cpu(nid_in_journal(journal, i)) == val)
2522 				return i;
2523 		}
2524 		if (alloc && __has_cursum_space(journal, 1, NAT_JOURNAL))
2525 			return update_nats_in_cursum(journal, 1);
2526 	} else if (type == SIT_JOURNAL) {
2527 		for (i = 0; i < sits_in_cursum(journal); i++)
2528 			if (le32_to_cpu(segno_in_journal(journal, i)) == val)
2529 				return i;
2530 		if (alloc && __has_cursum_space(journal, 1, SIT_JOURNAL))
2531 			return update_sits_in_cursum(journal, 1);
2532 	}
2533 	return -1;
2534 }
2535 
2536 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
2537 					unsigned int segno)
2538 {
2539 	return get_meta_page(sbi, current_sit_addr(sbi, segno));
2540 }
2541 
2542 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
2543 					unsigned int start)
2544 {
2545 	struct sit_info *sit_i = SIT_I(sbi);
2546 	struct page *src_page, *dst_page;
2547 	pgoff_t src_off, dst_off;
2548 	void *src_addr, *dst_addr;
2549 
2550 	src_off = current_sit_addr(sbi, start);
2551 	dst_off = next_sit_addr(sbi, src_off);
2552 
2553 	/* get current sit block page without lock */
2554 	src_page = get_meta_page(sbi, src_off);
2555 	dst_page = grab_meta_page(sbi, dst_off);
2556 	f2fs_bug_on(sbi, PageDirty(src_page));
2557 
2558 	src_addr = page_address(src_page);
2559 	dst_addr = page_address(dst_page);
2560 	memcpy(dst_addr, src_addr, PAGE_SIZE);
2561 
2562 	set_page_dirty(dst_page);
2563 	f2fs_put_page(src_page, 1);
2564 
2565 	set_to_next_sit(sit_i, start);
2566 
2567 	return dst_page;
2568 }
2569 
2570 static struct sit_entry_set *grab_sit_entry_set(void)
2571 {
2572 	struct sit_entry_set *ses =
2573 			f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
2574 
2575 	ses->entry_cnt = 0;
2576 	INIT_LIST_HEAD(&ses->set_list);
2577 	return ses;
2578 }
2579 
2580 static void release_sit_entry_set(struct sit_entry_set *ses)
2581 {
2582 	list_del(&ses->set_list);
2583 	kmem_cache_free(sit_entry_set_slab, ses);
2584 }
2585 
2586 static void adjust_sit_entry_set(struct sit_entry_set *ses,
2587 						struct list_head *head)
2588 {
2589 	struct sit_entry_set *next = ses;
2590 
2591 	if (list_is_last(&ses->set_list, head))
2592 		return;
2593 
2594 	list_for_each_entry_continue(next, head, set_list)
2595 		if (ses->entry_cnt <= next->entry_cnt)
2596 			break;
2597 
2598 	list_move_tail(&ses->set_list, &next->set_list);
2599 }
2600 
2601 static void add_sit_entry(unsigned int segno, struct list_head *head)
2602 {
2603 	struct sit_entry_set *ses;
2604 	unsigned int start_segno = START_SEGNO(segno);
2605 
2606 	list_for_each_entry(ses, head, set_list) {
2607 		if (ses->start_segno == start_segno) {
2608 			ses->entry_cnt++;
2609 			adjust_sit_entry_set(ses, head);
2610 			return;
2611 		}
2612 	}
2613 
2614 	ses = grab_sit_entry_set();
2615 
2616 	ses->start_segno = start_segno;
2617 	ses->entry_cnt++;
2618 	list_add(&ses->set_list, head);
2619 }
2620 
2621 static void add_sits_in_set(struct f2fs_sb_info *sbi)
2622 {
2623 	struct f2fs_sm_info *sm_info = SM_I(sbi);
2624 	struct list_head *set_list = &sm_info->sit_entry_set;
2625 	unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
2626 	unsigned int segno;
2627 
2628 	for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
2629 		add_sit_entry(segno, set_list);
2630 }
2631 
2632 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
2633 {
2634 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2635 	struct f2fs_journal *journal = curseg->journal;
2636 	int i;
2637 
2638 	down_write(&curseg->journal_rwsem);
2639 	for (i = 0; i < sits_in_cursum(journal); i++) {
2640 		unsigned int segno;
2641 		bool dirtied;
2642 
2643 		segno = le32_to_cpu(segno_in_journal(journal, i));
2644 		dirtied = __mark_sit_entry_dirty(sbi, segno);
2645 
2646 		if (!dirtied)
2647 			add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
2648 	}
2649 	update_sits_in_cursum(journal, -i);
2650 	up_write(&curseg->journal_rwsem);
2651 }
2652 
2653 /*
2654  * CP calls this function, which flushes SIT entries including sit_journal,
2655  * and moves prefree segs to free segs.
2656  */
2657 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
2658 {
2659 	struct sit_info *sit_i = SIT_I(sbi);
2660 	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
2661 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2662 	struct f2fs_journal *journal = curseg->journal;
2663 	struct sit_entry_set *ses, *tmp;
2664 	struct list_head *head = &SM_I(sbi)->sit_entry_set;
2665 	bool to_journal = true;
2666 	struct seg_entry *se;
2667 
2668 	mutex_lock(&sit_i->sentry_lock);
2669 
2670 	if (!sit_i->dirty_sentries)
2671 		goto out;
2672 
2673 	/*
2674 	 * add and account sit entries of dirty bitmap in sit entry
2675 	 * set temporarily
2676 	 */
2677 	add_sits_in_set(sbi);
2678 
2679 	/*
2680 	 * if there are no enough space in journal to store dirty sit
2681 	 * entries, remove all entries from journal and add and account
2682 	 * them in sit entry set.
2683 	 */
2684 	if (!__has_cursum_space(journal, sit_i->dirty_sentries, SIT_JOURNAL))
2685 		remove_sits_in_journal(sbi);
2686 
2687 	/*
2688 	 * there are two steps to flush sit entries:
2689 	 * #1, flush sit entries to journal in current cold data summary block.
2690 	 * #2, flush sit entries to sit page.
2691 	 */
2692 	list_for_each_entry_safe(ses, tmp, head, set_list) {
2693 		struct page *page = NULL;
2694 		struct f2fs_sit_block *raw_sit = NULL;
2695 		unsigned int start_segno = ses->start_segno;
2696 		unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
2697 						(unsigned long)MAIN_SEGS(sbi));
2698 		unsigned int segno = start_segno;
2699 
2700 		if (to_journal &&
2701 			!__has_cursum_space(journal, ses->entry_cnt, SIT_JOURNAL))
2702 			to_journal = false;
2703 
2704 		if (to_journal) {
2705 			down_write(&curseg->journal_rwsem);
2706 		} else {
2707 			page = get_next_sit_page(sbi, start_segno);
2708 			raw_sit = page_address(page);
2709 		}
2710 
2711 		/* flush dirty sit entries in region of current sit set */
2712 		for_each_set_bit_from(segno, bitmap, end) {
2713 			int offset, sit_offset;
2714 
2715 			se = get_seg_entry(sbi, segno);
2716 
2717 			/* add discard candidates */
2718 			if (cpc->reason != CP_DISCARD) {
2719 				cpc->trim_start = segno;
2720 				add_discard_addrs(sbi, cpc, false);
2721 			}
2722 
2723 			if (to_journal) {
2724 				offset = lookup_journal_in_cursum(journal,
2725 							SIT_JOURNAL, segno, 1);
2726 				f2fs_bug_on(sbi, offset < 0);
2727 				segno_in_journal(journal, offset) =
2728 							cpu_to_le32(segno);
2729 				seg_info_to_raw_sit(se,
2730 					&sit_in_journal(journal, offset));
2731 			} else {
2732 				sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
2733 				seg_info_to_raw_sit(se,
2734 						&raw_sit->entries[sit_offset]);
2735 			}
2736 
2737 			__clear_bit(segno, bitmap);
2738 			sit_i->dirty_sentries--;
2739 			ses->entry_cnt--;
2740 		}
2741 
2742 		if (to_journal)
2743 			up_write(&curseg->journal_rwsem);
2744 		else
2745 			f2fs_put_page(page, 1);
2746 
2747 		f2fs_bug_on(sbi, ses->entry_cnt);
2748 		release_sit_entry_set(ses);
2749 	}
2750 
2751 	f2fs_bug_on(sbi, !list_empty(head));
2752 	f2fs_bug_on(sbi, sit_i->dirty_sentries);
2753 out:
2754 	if (cpc->reason == CP_DISCARD) {
2755 		__u64 trim_start = cpc->trim_start;
2756 
2757 		for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
2758 			add_discard_addrs(sbi, cpc, false);
2759 
2760 		cpc->trim_start = trim_start;
2761 	}
2762 	mutex_unlock(&sit_i->sentry_lock);
2763 
2764 	set_prefree_as_free_segments(sbi);
2765 }
2766 
2767 static int build_sit_info(struct f2fs_sb_info *sbi)
2768 {
2769 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2770 	struct sit_info *sit_i;
2771 	unsigned int sit_segs, start;
2772 	char *src_bitmap;
2773 	unsigned int bitmap_size;
2774 
2775 	/* allocate memory for SIT information */
2776 	sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
2777 	if (!sit_i)
2778 		return -ENOMEM;
2779 
2780 	SM_I(sbi)->sit_info = sit_i;
2781 
2782 	sit_i->sentries = f2fs_kvzalloc(MAIN_SEGS(sbi) *
2783 					sizeof(struct seg_entry), GFP_KERNEL);
2784 	if (!sit_i->sentries)
2785 		return -ENOMEM;
2786 
2787 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2788 	sit_i->dirty_sentries_bitmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
2789 	if (!sit_i->dirty_sentries_bitmap)
2790 		return -ENOMEM;
2791 
2792 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2793 		sit_i->sentries[start].cur_valid_map
2794 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2795 		sit_i->sentries[start].ckpt_valid_map
2796 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2797 		if (!sit_i->sentries[start].cur_valid_map ||
2798 				!sit_i->sentries[start].ckpt_valid_map)
2799 			return -ENOMEM;
2800 
2801 #ifdef CONFIG_F2FS_CHECK_FS
2802 		sit_i->sentries[start].cur_valid_map_mir
2803 			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2804 		if (!sit_i->sentries[start].cur_valid_map_mir)
2805 			return -ENOMEM;
2806 #endif
2807 
2808 		if (f2fs_discard_en(sbi)) {
2809 			sit_i->sentries[start].discard_map
2810 				= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2811 			if (!sit_i->sentries[start].discard_map)
2812 				return -ENOMEM;
2813 		}
2814 	}
2815 
2816 	sit_i->tmp_map = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
2817 	if (!sit_i->tmp_map)
2818 		return -ENOMEM;
2819 
2820 	if (sbi->segs_per_sec > 1) {
2821 		sit_i->sec_entries = f2fs_kvzalloc(MAIN_SECS(sbi) *
2822 					sizeof(struct sec_entry), GFP_KERNEL);
2823 		if (!sit_i->sec_entries)
2824 			return -ENOMEM;
2825 	}
2826 
2827 	/* get information related with SIT */
2828 	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
2829 
2830 	/* setup SIT bitmap from ckeckpoint pack */
2831 	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
2832 	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
2833 
2834 	sit_i->sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
2835 	if (!sit_i->sit_bitmap)
2836 		return -ENOMEM;
2837 
2838 #ifdef CONFIG_F2FS_CHECK_FS
2839 	sit_i->sit_bitmap_mir = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
2840 	if (!sit_i->sit_bitmap_mir)
2841 		return -ENOMEM;
2842 #endif
2843 
2844 	/* init SIT information */
2845 	sit_i->s_ops = &default_salloc_ops;
2846 
2847 	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
2848 	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
2849 	sit_i->written_valid_blocks = 0;
2850 	sit_i->bitmap_size = bitmap_size;
2851 	sit_i->dirty_sentries = 0;
2852 	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
2853 	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
2854 	sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
2855 	mutex_init(&sit_i->sentry_lock);
2856 	return 0;
2857 }
2858 
2859 static int build_free_segmap(struct f2fs_sb_info *sbi)
2860 {
2861 	struct free_segmap_info *free_i;
2862 	unsigned int bitmap_size, sec_bitmap_size;
2863 
2864 	/* allocate memory for free segmap information */
2865 	free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
2866 	if (!free_i)
2867 		return -ENOMEM;
2868 
2869 	SM_I(sbi)->free_info = free_i;
2870 
2871 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2872 	free_i->free_segmap = f2fs_kvmalloc(bitmap_size, GFP_KERNEL);
2873 	if (!free_i->free_segmap)
2874 		return -ENOMEM;
2875 
2876 	sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2877 	free_i->free_secmap = f2fs_kvmalloc(sec_bitmap_size, GFP_KERNEL);
2878 	if (!free_i->free_secmap)
2879 		return -ENOMEM;
2880 
2881 	/* set all segments as dirty temporarily */
2882 	memset(free_i->free_segmap, 0xff, bitmap_size);
2883 	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
2884 
2885 	/* init free segmap information */
2886 	free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
2887 	free_i->free_segments = 0;
2888 	free_i->free_sections = 0;
2889 	spin_lock_init(&free_i->segmap_lock);
2890 	return 0;
2891 }
2892 
2893 static int build_curseg(struct f2fs_sb_info *sbi)
2894 {
2895 	struct curseg_info *array;
2896 	int i;
2897 
2898 	array = kcalloc(NR_CURSEG_TYPE, sizeof(*array), GFP_KERNEL);
2899 	if (!array)
2900 		return -ENOMEM;
2901 
2902 	SM_I(sbi)->curseg_array = array;
2903 
2904 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
2905 		mutex_init(&array[i].curseg_mutex);
2906 		array[i].sum_blk = kzalloc(PAGE_SIZE, GFP_KERNEL);
2907 		if (!array[i].sum_blk)
2908 			return -ENOMEM;
2909 		init_rwsem(&array[i].journal_rwsem);
2910 		array[i].journal = kzalloc(sizeof(struct f2fs_journal),
2911 							GFP_KERNEL);
2912 		if (!array[i].journal)
2913 			return -ENOMEM;
2914 		array[i].segno = NULL_SEGNO;
2915 		array[i].next_blkoff = 0;
2916 	}
2917 	return restore_curseg_summaries(sbi);
2918 }
2919 
2920 static void build_sit_entries(struct f2fs_sb_info *sbi)
2921 {
2922 	struct sit_info *sit_i = SIT_I(sbi);
2923 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2924 	struct f2fs_journal *journal = curseg->journal;
2925 	struct seg_entry *se;
2926 	struct f2fs_sit_entry sit;
2927 	int sit_blk_cnt = SIT_BLK_CNT(sbi);
2928 	unsigned int i, start, end;
2929 	unsigned int readed, start_blk = 0;
2930 
2931 	do {
2932 		readed = ra_meta_pages(sbi, start_blk, BIO_MAX_PAGES,
2933 							META_SIT, true);
2934 
2935 		start = start_blk * sit_i->sents_per_block;
2936 		end = (start_blk + readed) * sit_i->sents_per_block;
2937 
2938 		for (; start < end && start < MAIN_SEGS(sbi); start++) {
2939 			struct f2fs_sit_block *sit_blk;
2940 			struct page *page;
2941 
2942 			se = &sit_i->sentries[start];
2943 			page = get_current_sit_page(sbi, start);
2944 			sit_blk = (struct f2fs_sit_block *)page_address(page);
2945 			sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
2946 			f2fs_put_page(page, 1);
2947 
2948 			check_block_count(sbi, start, &sit);
2949 			seg_info_from_raw_sit(se, &sit);
2950 
2951 			/* build discard map only one time */
2952 			if (f2fs_discard_en(sbi)) {
2953 				memcpy(se->discard_map, se->cur_valid_map,
2954 							SIT_VBLOCK_MAP_SIZE);
2955 				sbi->discard_blks += sbi->blocks_per_seg -
2956 							se->valid_blocks;
2957 			}
2958 
2959 			if (sbi->segs_per_sec > 1)
2960 				get_sec_entry(sbi, start)->valid_blocks +=
2961 							se->valid_blocks;
2962 		}
2963 		start_blk += readed;
2964 	} while (start_blk < sit_blk_cnt);
2965 
2966 	down_read(&curseg->journal_rwsem);
2967 	for (i = 0; i < sits_in_cursum(journal); i++) {
2968 		unsigned int old_valid_blocks;
2969 
2970 		start = le32_to_cpu(segno_in_journal(journal, i));
2971 		se = &sit_i->sentries[start];
2972 		sit = sit_in_journal(journal, i);
2973 
2974 		old_valid_blocks = se->valid_blocks;
2975 
2976 		check_block_count(sbi, start, &sit);
2977 		seg_info_from_raw_sit(se, &sit);
2978 
2979 		if (f2fs_discard_en(sbi)) {
2980 			memcpy(se->discard_map, se->cur_valid_map,
2981 						SIT_VBLOCK_MAP_SIZE);
2982 			sbi->discard_blks += old_valid_blocks -
2983 						se->valid_blocks;
2984 		}
2985 
2986 		if (sbi->segs_per_sec > 1)
2987 			get_sec_entry(sbi, start)->valid_blocks +=
2988 				se->valid_blocks - old_valid_blocks;
2989 	}
2990 	up_read(&curseg->journal_rwsem);
2991 }
2992 
2993 static void init_free_segmap(struct f2fs_sb_info *sbi)
2994 {
2995 	unsigned int start;
2996 	int type;
2997 
2998 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
2999 		struct seg_entry *sentry = get_seg_entry(sbi, start);
3000 		if (!sentry->valid_blocks)
3001 			__set_free(sbi, start);
3002 		else
3003 			SIT_I(sbi)->written_valid_blocks +=
3004 						sentry->valid_blocks;
3005 	}
3006 
3007 	/* set use the current segments */
3008 	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
3009 		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
3010 		__set_test_and_inuse(sbi, curseg_t->segno);
3011 	}
3012 }
3013 
3014 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
3015 {
3016 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3017 	struct free_segmap_info *free_i = FREE_I(sbi);
3018 	unsigned int segno = 0, offset = 0;
3019 	unsigned short valid_blocks;
3020 
3021 	while (1) {
3022 		/* find dirty segment based on free segmap */
3023 		segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
3024 		if (segno >= MAIN_SEGS(sbi))
3025 			break;
3026 		offset = segno + 1;
3027 		valid_blocks = get_valid_blocks(sbi, segno, false);
3028 		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
3029 			continue;
3030 		if (valid_blocks > sbi->blocks_per_seg) {
3031 			f2fs_bug_on(sbi, 1);
3032 			continue;
3033 		}
3034 		mutex_lock(&dirty_i->seglist_lock);
3035 		__locate_dirty_segment(sbi, segno, DIRTY);
3036 		mutex_unlock(&dirty_i->seglist_lock);
3037 	}
3038 }
3039 
3040 static int init_victim_secmap(struct f2fs_sb_info *sbi)
3041 {
3042 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3043 	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
3044 
3045 	dirty_i->victim_secmap = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
3046 	if (!dirty_i->victim_secmap)
3047 		return -ENOMEM;
3048 	return 0;
3049 }
3050 
3051 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
3052 {
3053 	struct dirty_seglist_info *dirty_i;
3054 	unsigned int bitmap_size, i;
3055 
3056 	/* allocate memory for dirty segments list information */
3057 	dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
3058 	if (!dirty_i)
3059 		return -ENOMEM;
3060 
3061 	SM_I(sbi)->dirty_info = dirty_i;
3062 	mutex_init(&dirty_i->seglist_lock);
3063 
3064 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3065 
3066 	for (i = 0; i < NR_DIRTY_TYPE; i++) {
3067 		dirty_i->dirty_segmap[i] = f2fs_kvzalloc(bitmap_size, GFP_KERNEL);
3068 		if (!dirty_i->dirty_segmap[i])
3069 			return -ENOMEM;
3070 	}
3071 
3072 	init_dirty_segmap(sbi);
3073 	return init_victim_secmap(sbi);
3074 }
3075 
3076 /*
3077  * Update min, max modified time for cost-benefit GC algorithm
3078  */
3079 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
3080 {
3081 	struct sit_info *sit_i = SIT_I(sbi);
3082 	unsigned int segno;
3083 
3084 	mutex_lock(&sit_i->sentry_lock);
3085 
3086 	sit_i->min_mtime = LLONG_MAX;
3087 
3088 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
3089 		unsigned int i;
3090 		unsigned long long mtime = 0;
3091 
3092 		for (i = 0; i < sbi->segs_per_sec; i++)
3093 			mtime += get_seg_entry(sbi, segno + i)->mtime;
3094 
3095 		mtime = div_u64(mtime, sbi->segs_per_sec);
3096 
3097 		if (sit_i->min_mtime > mtime)
3098 			sit_i->min_mtime = mtime;
3099 	}
3100 	sit_i->max_mtime = get_mtime(sbi);
3101 	mutex_unlock(&sit_i->sentry_lock);
3102 }
3103 
3104 int build_segment_manager(struct f2fs_sb_info *sbi)
3105 {
3106 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
3107 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3108 	struct f2fs_sm_info *sm_info;
3109 	int err;
3110 
3111 	sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
3112 	if (!sm_info)
3113 		return -ENOMEM;
3114 
3115 	/* init sm info */
3116 	sbi->sm_info = sm_info;
3117 	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
3118 	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
3119 	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
3120 	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
3121 	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
3122 	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
3123 	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
3124 	sm_info->rec_prefree_segments = sm_info->main_segments *
3125 					DEF_RECLAIM_PREFREE_SEGMENTS / 100;
3126 	if (sm_info->rec_prefree_segments > DEF_MAX_RECLAIM_PREFREE_SEGMENTS)
3127 		sm_info->rec_prefree_segments = DEF_MAX_RECLAIM_PREFREE_SEGMENTS;
3128 
3129 	if (!test_opt(sbi, LFS))
3130 		sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
3131 	sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
3132 	sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
3133 	sm_info->min_hot_blocks = DEF_MIN_HOT_BLOCKS;
3134 
3135 	sm_info->trim_sections = DEF_BATCHED_TRIM_SECTIONS;
3136 
3137 	INIT_LIST_HEAD(&sm_info->sit_entry_set);
3138 
3139 	if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) {
3140 		err = create_flush_cmd_control(sbi);
3141 		if (err)
3142 			return err;
3143 	}
3144 
3145 	err = create_discard_cmd_control(sbi);
3146 	if (err)
3147 		return err;
3148 
3149 	err = build_sit_info(sbi);
3150 	if (err)
3151 		return err;
3152 	err = build_free_segmap(sbi);
3153 	if (err)
3154 		return err;
3155 	err = build_curseg(sbi);
3156 	if (err)
3157 		return err;
3158 
3159 	/* reinit free segmap based on SIT */
3160 	build_sit_entries(sbi);
3161 
3162 	init_free_segmap(sbi);
3163 	err = build_dirty_segmap(sbi);
3164 	if (err)
3165 		return err;
3166 
3167 	init_min_max_mtime(sbi);
3168 	return 0;
3169 }
3170 
3171 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
3172 		enum dirty_type dirty_type)
3173 {
3174 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3175 
3176 	mutex_lock(&dirty_i->seglist_lock);
3177 	kvfree(dirty_i->dirty_segmap[dirty_type]);
3178 	dirty_i->nr_dirty[dirty_type] = 0;
3179 	mutex_unlock(&dirty_i->seglist_lock);
3180 }
3181 
3182 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
3183 {
3184 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3185 	kvfree(dirty_i->victim_secmap);
3186 }
3187 
3188 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
3189 {
3190 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3191 	int i;
3192 
3193 	if (!dirty_i)
3194 		return;
3195 
3196 	/* discard pre-free/dirty segments list */
3197 	for (i = 0; i < NR_DIRTY_TYPE; i++)
3198 		discard_dirty_segmap(sbi, i);
3199 
3200 	destroy_victim_secmap(sbi);
3201 	SM_I(sbi)->dirty_info = NULL;
3202 	kfree(dirty_i);
3203 }
3204 
3205 static void destroy_curseg(struct f2fs_sb_info *sbi)
3206 {
3207 	struct curseg_info *array = SM_I(sbi)->curseg_array;
3208 	int i;
3209 
3210 	if (!array)
3211 		return;
3212 	SM_I(sbi)->curseg_array = NULL;
3213 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
3214 		kfree(array[i].sum_blk);
3215 		kfree(array[i].journal);
3216 	}
3217 	kfree(array);
3218 }
3219 
3220 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
3221 {
3222 	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
3223 	if (!free_i)
3224 		return;
3225 	SM_I(sbi)->free_info = NULL;
3226 	kvfree(free_i->free_segmap);
3227 	kvfree(free_i->free_secmap);
3228 	kfree(free_i);
3229 }
3230 
3231 static void destroy_sit_info(struct f2fs_sb_info *sbi)
3232 {
3233 	struct sit_info *sit_i = SIT_I(sbi);
3234 	unsigned int start;
3235 
3236 	if (!sit_i)
3237 		return;
3238 
3239 	if (sit_i->sentries) {
3240 		for (start = 0; start < MAIN_SEGS(sbi); start++) {
3241 			kfree(sit_i->sentries[start].cur_valid_map);
3242 #ifdef CONFIG_F2FS_CHECK_FS
3243 			kfree(sit_i->sentries[start].cur_valid_map_mir);
3244 #endif
3245 			kfree(sit_i->sentries[start].ckpt_valid_map);
3246 			kfree(sit_i->sentries[start].discard_map);
3247 		}
3248 	}
3249 	kfree(sit_i->tmp_map);
3250 
3251 	kvfree(sit_i->sentries);
3252 	kvfree(sit_i->sec_entries);
3253 	kvfree(sit_i->dirty_sentries_bitmap);
3254 
3255 	SM_I(sbi)->sit_info = NULL;
3256 	kfree(sit_i->sit_bitmap);
3257 #ifdef CONFIG_F2FS_CHECK_FS
3258 	kfree(sit_i->sit_bitmap_mir);
3259 #endif
3260 	kfree(sit_i);
3261 }
3262 
3263 void destroy_segment_manager(struct f2fs_sb_info *sbi)
3264 {
3265 	struct f2fs_sm_info *sm_info = SM_I(sbi);
3266 
3267 	if (!sm_info)
3268 		return;
3269 	destroy_flush_cmd_control(sbi, true);
3270 	destroy_discard_cmd_control(sbi);
3271 	destroy_dirty_segmap(sbi);
3272 	destroy_curseg(sbi);
3273 	destroy_free_segmap(sbi);
3274 	destroy_sit_info(sbi);
3275 	sbi->sm_info = NULL;
3276 	kfree(sm_info);
3277 }
3278 
3279 int __init create_segment_manager_caches(void)
3280 {
3281 	discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
3282 			sizeof(struct discard_entry));
3283 	if (!discard_entry_slab)
3284 		goto fail;
3285 
3286 	discard_cmd_slab = f2fs_kmem_cache_create("discard_cmd",
3287 			sizeof(struct discard_cmd));
3288 	if (!discard_cmd_slab)
3289 		goto destroy_discard_entry;
3290 
3291 	sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
3292 			sizeof(struct sit_entry_set));
3293 	if (!sit_entry_set_slab)
3294 		goto destroy_discard_cmd;
3295 
3296 	inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
3297 			sizeof(struct inmem_pages));
3298 	if (!inmem_entry_slab)
3299 		goto destroy_sit_entry_set;
3300 	return 0;
3301 
3302 destroy_sit_entry_set:
3303 	kmem_cache_destroy(sit_entry_set_slab);
3304 destroy_discard_cmd:
3305 	kmem_cache_destroy(discard_cmd_slab);
3306 destroy_discard_entry:
3307 	kmem_cache_destroy(discard_entry_slab);
3308 fail:
3309 	return -ENOMEM;
3310 }
3311 
3312 void destroy_segment_manager_caches(void)
3313 {
3314 	kmem_cache_destroy(sit_entry_set_slab);
3315 	kmem_cache_destroy(discard_cmd_slab);
3316 	kmem_cache_destroy(discard_entry_slab);
3317 	kmem_cache_destroy(inmem_entry_slab);
3318 }
3319