xref: /openbmc/linux/fs/f2fs/segment.c (revision 5b0e95398e2bcc18e871758221cc712be4a0a39a)
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 #include <linux/freezer.h>
20 #include <linux/sched/signal.h>
21 
22 #include "f2fs.h"
23 #include "segment.h"
24 #include "node.h"
25 #include "gc.h"
26 #include "trace.h"
27 #include <trace/events/f2fs.h>
28 
29 #define __reverse_ffz(x) __reverse_ffs(~(x))
30 
31 static struct kmem_cache *discard_entry_slab;
32 static struct kmem_cache *discard_cmd_slab;
33 static struct kmem_cache *sit_entry_set_slab;
34 static struct kmem_cache *inmem_entry_slab;
35 
36 static unsigned long __reverse_ulong(unsigned char *str)
37 {
38 	unsigned long tmp = 0;
39 	int shift = 24, idx = 0;
40 
41 #if BITS_PER_LONG == 64
42 	shift = 56;
43 #endif
44 	while (shift >= 0) {
45 		tmp |= (unsigned long)str[idx++] << shift;
46 		shift -= BITS_PER_BYTE;
47 	}
48 	return tmp;
49 }
50 
51 /*
52  * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
53  * MSB and LSB are reversed in a byte by f2fs_set_bit.
54  */
55 static inline unsigned long __reverse_ffs(unsigned long word)
56 {
57 	int num = 0;
58 
59 #if BITS_PER_LONG == 64
60 	if ((word & 0xffffffff00000000UL) == 0)
61 		num += 32;
62 	else
63 		word >>= 32;
64 #endif
65 	if ((word & 0xffff0000) == 0)
66 		num += 16;
67 	else
68 		word >>= 16;
69 
70 	if ((word & 0xff00) == 0)
71 		num += 8;
72 	else
73 		word >>= 8;
74 
75 	if ((word & 0xf0) == 0)
76 		num += 4;
77 	else
78 		word >>= 4;
79 
80 	if ((word & 0xc) == 0)
81 		num += 2;
82 	else
83 		word >>= 2;
84 
85 	if ((word & 0x2) == 0)
86 		num += 1;
87 	return num;
88 }
89 
90 /*
91  * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because
92  * f2fs_set_bit makes MSB and LSB reversed in a byte.
93  * @size must be integral times of unsigned long.
94  * Example:
95  *                             MSB <--> LSB
96  *   f2fs_set_bit(0, bitmap) => 1000 0000
97  *   f2fs_set_bit(7, bitmap) => 0000 0001
98  */
99 static unsigned long __find_rev_next_bit(const unsigned long *addr,
100 			unsigned long size, unsigned long offset)
101 {
102 	const unsigned long *p = addr + BIT_WORD(offset);
103 	unsigned long result = size;
104 	unsigned long tmp;
105 
106 	if (offset >= size)
107 		return size;
108 
109 	size -= (offset & ~(BITS_PER_LONG - 1));
110 	offset %= BITS_PER_LONG;
111 
112 	while (1) {
113 		if (*p == 0)
114 			goto pass;
115 
116 		tmp = __reverse_ulong((unsigned char *)p);
117 
118 		tmp &= ~0UL >> offset;
119 		if (size < BITS_PER_LONG)
120 			tmp &= (~0UL << (BITS_PER_LONG - size));
121 		if (tmp)
122 			goto found;
123 pass:
124 		if (size <= BITS_PER_LONG)
125 			break;
126 		size -= BITS_PER_LONG;
127 		offset = 0;
128 		p++;
129 	}
130 	return result;
131 found:
132 	return result - size + __reverse_ffs(tmp);
133 }
134 
135 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
136 			unsigned long size, unsigned long offset)
137 {
138 	const unsigned long *p = addr + BIT_WORD(offset);
139 	unsigned long result = size;
140 	unsigned long tmp;
141 
142 	if (offset >= size)
143 		return size;
144 
145 	size -= (offset & ~(BITS_PER_LONG - 1));
146 	offset %= BITS_PER_LONG;
147 
148 	while (1) {
149 		if (*p == ~0UL)
150 			goto pass;
151 
152 		tmp = __reverse_ulong((unsigned char *)p);
153 
154 		if (offset)
155 			tmp |= ~0UL << (BITS_PER_LONG - offset);
156 		if (size < BITS_PER_LONG)
157 			tmp |= ~0UL >> size;
158 		if (tmp != ~0UL)
159 			goto found;
160 pass:
161 		if (size <= BITS_PER_LONG)
162 			break;
163 		size -= BITS_PER_LONG;
164 		offset = 0;
165 		p++;
166 	}
167 	return result;
168 found:
169 	return result - size + __reverse_ffz(tmp);
170 }
171 
172 bool need_SSR(struct f2fs_sb_info *sbi)
173 {
174 	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
175 	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
176 	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
177 
178 	if (test_opt(sbi, LFS))
179 		return false;
180 	if (sbi->gc_mode == GC_URGENT)
181 		return true;
182 
183 	return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
184 			SM_I(sbi)->min_ssr_sections + reserved_sections(sbi));
185 }
186 
187 void register_inmem_page(struct inode *inode, struct page *page)
188 {
189 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
190 	struct f2fs_inode_info *fi = F2FS_I(inode);
191 	struct inmem_pages *new;
192 
193 	f2fs_trace_pid(page);
194 
195 	set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE);
196 	SetPagePrivate(page);
197 
198 	new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
199 
200 	/* add atomic page indices to the list */
201 	new->page = page;
202 	INIT_LIST_HEAD(&new->list);
203 
204 	/* increase reference count with clean state */
205 	mutex_lock(&fi->inmem_lock);
206 	get_page(page);
207 	list_add_tail(&new->list, &fi->inmem_pages);
208 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
209 	if (list_empty(&fi->inmem_ilist))
210 		list_add_tail(&fi->inmem_ilist, &sbi->inode_list[ATOMIC_FILE]);
211 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
212 	inc_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
213 	mutex_unlock(&fi->inmem_lock);
214 
215 	trace_f2fs_register_inmem_page(page, INMEM);
216 }
217 
218 static int __revoke_inmem_pages(struct inode *inode,
219 				struct list_head *head, bool drop, bool recover)
220 {
221 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
222 	struct inmem_pages *cur, *tmp;
223 	int err = 0;
224 
225 	list_for_each_entry_safe(cur, tmp, head, list) {
226 		struct page *page = cur->page;
227 
228 		if (drop)
229 			trace_f2fs_commit_inmem_page(page, INMEM_DROP);
230 
231 		lock_page(page);
232 
233 		f2fs_wait_on_page_writeback(page, DATA, true);
234 
235 		if (recover) {
236 			struct dnode_of_data dn;
237 			struct node_info ni;
238 
239 			trace_f2fs_commit_inmem_page(page, INMEM_REVOKE);
240 retry:
241 			set_new_dnode(&dn, inode, NULL, NULL, 0);
242 			err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
243 			if (err) {
244 				if (err == -ENOMEM) {
245 					congestion_wait(BLK_RW_ASYNC, HZ/50);
246 					cond_resched();
247 					goto retry;
248 				}
249 				err = -EAGAIN;
250 				goto next;
251 			}
252 			get_node_info(sbi, dn.nid, &ni);
253 			if (cur->old_addr == NEW_ADDR) {
254 				invalidate_blocks(sbi, dn.data_blkaddr);
255 				f2fs_update_data_blkaddr(&dn, NEW_ADDR);
256 			} else
257 				f2fs_replace_block(sbi, &dn, dn.data_blkaddr,
258 					cur->old_addr, ni.version, true, true);
259 			f2fs_put_dnode(&dn);
260 		}
261 next:
262 		/* we don't need to invalidate this in the sccessful status */
263 		if (drop || recover)
264 			ClearPageUptodate(page);
265 		set_page_private(page, 0);
266 		ClearPagePrivate(page);
267 		f2fs_put_page(page, 1);
268 
269 		list_del(&cur->list);
270 		kmem_cache_free(inmem_entry_slab, cur);
271 		dec_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
272 	}
273 	return err;
274 }
275 
276 void drop_inmem_pages_all(struct f2fs_sb_info *sbi)
277 {
278 	struct list_head *head = &sbi->inode_list[ATOMIC_FILE];
279 	struct inode *inode;
280 	struct f2fs_inode_info *fi;
281 next:
282 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
283 	if (list_empty(head)) {
284 		spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
285 		return;
286 	}
287 	fi = list_first_entry(head, struct f2fs_inode_info, inmem_ilist);
288 	inode = igrab(&fi->vfs_inode);
289 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
290 
291 	if (inode) {
292 		drop_inmem_pages(inode);
293 		iput(inode);
294 	}
295 	congestion_wait(BLK_RW_ASYNC, HZ/50);
296 	cond_resched();
297 	goto next;
298 }
299 
300 void drop_inmem_pages(struct inode *inode)
301 {
302 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
303 	struct f2fs_inode_info *fi = F2FS_I(inode);
304 
305 	mutex_lock(&fi->inmem_lock);
306 	__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
307 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
308 	if (!list_empty(&fi->inmem_ilist))
309 		list_del_init(&fi->inmem_ilist);
310 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
311 	mutex_unlock(&fi->inmem_lock);
312 
313 	clear_inode_flag(inode, FI_ATOMIC_FILE);
314 	stat_dec_atomic_write(inode);
315 }
316 
317 void drop_inmem_page(struct inode *inode, struct page *page)
318 {
319 	struct f2fs_inode_info *fi = F2FS_I(inode);
320 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
321 	struct list_head *head = &fi->inmem_pages;
322 	struct inmem_pages *cur = NULL;
323 
324 	f2fs_bug_on(sbi, !IS_ATOMIC_WRITTEN_PAGE(page));
325 
326 	mutex_lock(&fi->inmem_lock);
327 	list_for_each_entry(cur, head, list) {
328 		if (cur->page == page)
329 			break;
330 	}
331 
332 	f2fs_bug_on(sbi, list_empty(head) || cur->page != page);
333 	list_del(&cur->list);
334 	mutex_unlock(&fi->inmem_lock);
335 
336 	dec_page_count(sbi, F2FS_INMEM_PAGES);
337 	kmem_cache_free(inmem_entry_slab, cur);
338 
339 	ClearPageUptodate(page);
340 	set_page_private(page, 0);
341 	ClearPagePrivate(page);
342 	f2fs_put_page(page, 0);
343 
344 	trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE);
345 }
346 
347 static int __commit_inmem_pages(struct inode *inode)
348 {
349 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
350 	struct f2fs_inode_info *fi = F2FS_I(inode);
351 	struct inmem_pages *cur, *tmp;
352 	struct f2fs_io_info fio = {
353 		.sbi = sbi,
354 		.ino = inode->i_ino,
355 		.type = DATA,
356 		.op = REQ_OP_WRITE,
357 		.op_flags = REQ_SYNC | REQ_PRIO,
358 		.io_type = FS_DATA_IO,
359 	};
360 	struct list_head revoke_list;
361 	pgoff_t last_idx = ULONG_MAX;
362 	int err = 0;
363 
364 	INIT_LIST_HEAD(&revoke_list);
365 
366 	list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
367 		struct page *page = cur->page;
368 
369 		lock_page(page);
370 		if (page->mapping == inode->i_mapping) {
371 			trace_f2fs_commit_inmem_page(page, INMEM);
372 
373 			set_page_dirty(page);
374 			f2fs_wait_on_page_writeback(page, DATA, true);
375 			if (clear_page_dirty_for_io(page)) {
376 				inode_dec_dirty_pages(inode);
377 				remove_dirty_inode(inode);
378 			}
379 retry:
380 			fio.page = page;
381 			fio.old_blkaddr = NULL_ADDR;
382 			fio.encrypted_page = NULL;
383 			fio.need_lock = LOCK_DONE;
384 			err = do_write_data_page(&fio);
385 			if (err) {
386 				if (err == -ENOMEM) {
387 					congestion_wait(BLK_RW_ASYNC, HZ/50);
388 					cond_resched();
389 					goto retry;
390 				}
391 				unlock_page(page);
392 				break;
393 			}
394 			/* record old blkaddr for revoking */
395 			cur->old_addr = fio.old_blkaddr;
396 			last_idx = page->index;
397 		}
398 		unlock_page(page);
399 		list_move_tail(&cur->list, &revoke_list);
400 	}
401 
402 	if (last_idx != ULONG_MAX)
403 		f2fs_submit_merged_write_cond(sbi, inode, 0, last_idx, DATA);
404 
405 	if (err) {
406 		/*
407 		 * try to revoke all committed pages, but still we could fail
408 		 * due to no memory or other reason, if that happened, EAGAIN
409 		 * will be returned, which means in such case, transaction is
410 		 * already not integrity, caller should use journal to do the
411 		 * recovery or rewrite & commit last transaction. For other
412 		 * error number, revoking was done by filesystem itself.
413 		 */
414 		err = __revoke_inmem_pages(inode, &revoke_list, false, true);
415 
416 		/* drop all uncommitted pages */
417 		__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
418 	} else {
419 		__revoke_inmem_pages(inode, &revoke_list, false, false);
420 	}
421 
422 	return err;
423 }
424 
425 int commit_inmem_pages(struct inode *inode)
426 {
427 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
428 	struct f2fs_inode_info *fi = F2FS_I(inode);
429 	int err;
430 
431 	f2fs_balance_fs(sbi, true);
432 	f2fs_lock_op(sbi);
433 
434 	set_inode_flag(inode, FI_ATOMIC_COMMIT);
435 
436 	mutex_lock(&fi->inmem_lock);
437 	err = __commit_inmem_pages(inode);
438 
439 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
440 	if (!list_empty(&fi->inmem_ilist))
441 		list_del_init(&fi->inmem_ilist);
442 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
443 	mutex_unlock(&fi->inmem_lock);
444 
445 	clear_inode_flag(inode, FI_ATOMIC_COMMIT);
446 
447 	f2fs_unlock_op(sbi);
448 	return err;
449 }
450 
451 /*
452  * This function balances dirty node and dentry pages.
453  * In addition, it controls garbage collection.
454  */
455 void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
456 {
457 #ifdef CONFIG_F2FS_FAULT_INJECTION
458 	if (time_to_inject(sbi, FAULT_CHECKPOINT)) {
459 		f2fs_show_injection_info(FAULT_CHECKPOINT);
460 		f2fs_stop_checkpoint(sbi, false);
461 	}
462 #endif
463 
464 	/* balance_fs_bg is able to be pending */
465 	if (need && excess_cached_nats(sbi))
466 		f2fs_balance_fs_bg(sbi);
467 
468 	/*
469 	 * We should do GC or end up with checkpoint, if there are so many dirty
470 	 * dir/node pages without enough free segments.
471 	 */
472 	if (has_not_enough_free_secs(sbi, 0, 0)) {
473 		mutex_lock(&sbi->gc_mutex);
474 		f2fs_gc(sbi, false, false, NULL_SEGNO);
475 	}
476 }
477 
478 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
479 {
480 	/* try to shrink extent cache when there is no enough memory */
481 	if (!available_free_memory(sbi, EXTENT_CACHE))
482 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
483 
484 	/* check the # of cached NAT entries */
485 	if (!available_free_memory(sbi, NAT_ENTRIES))
486 		try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
487 
488 	if (!available_free_memory(sbi, FREE_NIDS))
489 		try_to_free_nids(sbi, MAX_FREE_NIDS);
490 	else
491 		build_free_nids(sbi, false, false);
492 
493 	if (!is_idle(sbi) && !excess_dirty_nats(sbi))
494 		return;
495 
496 	/* checkpoint is the only way to shrink partial cached entries */
497 	if (!available_free_memory(sbi, NAT_ENTRIES) ||
498 			!available_free_memory(sbi, INO_ENTRIES) ||
499 			excess_prefree_segs(sbi) ||
500 			excess_dirty_nats(sbi) ||
501 			f2fs_time_over(sbi, CP_TIME)) {
502 		if (test_opt(sbi, DATA_FLUSH)) {
503 			struct blk_plug plug;
504 
505 			blk_start_plug(&plug);
506 			sync_dirty_inodes(sbi, FILE_INODE);
507 			blk_finish_plug(&plug);
508 		}
509 		f2fs_sync_fs(sbi->sb, true);
510 		stat_inc_bg_cp_count(sbi->stat_info);
511 	}
512 }
513 
514 static int __submit_flush_wait(struct f2fs_sb_info *sbi,
515 				struct block_device *bdev)
516 {
517 	struct bio *bio = f2fs_bio_alloc(sbi, 0, true);
518 	int ret;
519 
520 	bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH;
521 	bio_set_dev(bio, bdev);
522 	ret = submit_bio_wait(bio);
523 	bio_put(bio);
524 
525 	trace_f2fs_issue_flush(bdev, test_opt(sbi, NOBARRIER),
526 				test_opt(sbi, FLUSH_MERGE), ret);
527 	return ret;
528 }
529 
530 static int submit_flush_wait(struct f2fs_sb_info *sbi, nid_t ino)
531 {
532 	int ret = 0;
533 	int i;
534 
535 	if (!sbi->s_ndevs)
536 		return __submit_flush_wait(sbi, sbi->sb->s_bdev);
537 
538 	for (i = 0; i < sbi->s_ndevs; i++) {
539 		if (!is_dirty_device(sbi, ino, i, FLUSH_INO))
540 			continue;
541 		ret = __submit_flush_wait(sbi, FDEV(i).bdev);
542 		if (ret)
543 			break;
544 	}
545 	return ret;
546 }
547 
548 static int issue_flush_thread(void *data)
549 {
550 	struct f2fs_sb_info *sbi = data;
551 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
552 	wait_queue_head_t *q = &fcc->flush_wait_queue;
553 repeat:
554 	if (kthread_should_stop())
555 		return 0;
556 
557 	sb_start_intwrite(sbi->sb);
558 
559 	if (!llist_empty(&fcc->issue_list)) {
560 		struct flush_cmd *cmd, *next;
561 		int ret;
562 
563 		fcc->dispatch_list = llist_del_all(&fcc->issue_list);
564 		fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
565 
566 		cmd = llist_entry(fcc->dispatch_list, struct flush_cmd, llnode);
567 
568 		ret = submit_flush_wait(sbi, cmd->ino);
569 		atomic_inc(&fcc->issued_flush);
570 
571 		llist_for_each_entry_safe(cmd, next,
572 					  fcc->dispatch_list, llnode) {
573 			cmd->ret = ret;
574 			complete(&cmd->wait);
575 		}
576 		fcc->dispatch_list = NULL;
577 	}
578 
579 	sb_end_intwrite(sbi->sb);
580 
581 	wait_event_interruptible(*q,
582 		kthread_should_stop() || !llist_empty(&fcc->issue_list));
583 	goto repeat;
584 }
585 
586 int f2fs_issue_flush(struct f2fs_sb_info *sbi, nid_t ino)
587 {
588 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
589 	struct flush_cmd cmd;
590 	int ret;
591 
592 	if (test_opt(sbi, NOBARRIER))
593 		return 0;
594 
595 	if (!test_opt(sbi, FLUSH_MERGE)) {
596 		ret = submit_flush_wait(sbi, ino);
597 		atomic_inc(&fcc->issued_flush);
598 		return ret;
599 	}
600 
601 	if (atomic_inc_return(&fcc->issing_flush) == 1 || sbi->s_ndevs > 1) {
602 		ret = submit_flush_wait(sbi, ino);
603 		atomic_dec(&fcc->issing_flush);
604 
605 		atomic_inc(&fcc->issued_flush);
606 		return ret;
607 	}
608 
609 	cmd.ino = ino;
610 	init_completion(&cmd.wait);
611 
612 	llist_add(&cmd.llnode, &fcc->issue_list);
613 
614 	/* update issue_list before we wake up issue_flush thread */
615 	smp_mb();
616 
617 	if (waitqueue_active(&fcc->flush_wait_queue))
618 		wake_up(&fcc->flush_wait_queue);
619 
620 	if (fcc->f2fs_issue_flush) {
621 		wait_for_completion(&cmd.wait);
622 		atomic_dec(&fcc->issing_flush);
623 	} else {
624 		struct llist_node *list;
625 
626 		list = llist_del_all(&fcc->issue_list);
627 		if (!list) {
628 			wait_for_completion(&cmd.wait);
629 			atomic_dec(&fcc->issing_flush);
630 		} else {
631 			struct flush_cmd *tmp, *next;
632 
633 			ret = submit_flush_wait(sbi, ino);
634 
635 			llist_for_each_entry_safe(tmp, next, list, llnode) {
636 				if (tmp == &cmd) {
637 					cmd.ret = ret;
638 					atomic_dec(&fcc->issing_flush);
639 					continue;
640 				}
641 				tmp->ret = ret;
642 				complete(&tmp->wait);
643 			}
644 		}
645 	}
646 
647 	return cmd.ret;
648 }
649 
650 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
651 {
652 	dev_t dev = sbi->sb->s_bdev->bd_dev;
653 	struct flush_cmd_control *fcc;
654 	int err = 0;
655 
656 	if (SM_I(sbi)->fcc_info) {
657 		fcc = SM_I(sbi)->fcc_info;
658 		if (fcc->f2fs_issue_flush)
659 			return err;
660 		goto init_thread;
661 	}
662 
663 	fcc = f2fs_kzalloc(sbi, sizeof(struct flush_cmd_control), GFP_KERNEL);
664 	if (!fcc)
665 		return -ENOMEM;
666 	atomic_set(&fcc->issued_flush, 0);
667 	atomic_set(&fcc->issing_flush, 0);
668 	init_waitqueue_head(&fcc->flush_wait_queue);
669 	init_llist_head(&fcc->issue_list);
670 	SM_I(sbi)->fcc_info = fcc;
671 	if (!test_opt(sbi, FLUSH_MERGE))
672 		return err;
673 
674 init_thread:
675 	fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
676 				"f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
677 	if (IS_ERR(fcc->f2fs_issue_flush)) {
678 		err = PTR_ERR(fcc->f2fs_issue_flush);
679 		kfree(fcc);
680 		SM_I(sbi)->fcc_info = NULL;
681 		return err;
682 	}
683 
684 	return err;
685 }
686 
687 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi, bool free)
688 {
689 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
690 
691 	if (fcc && fcc->f2fs_issue_flush) {
692 		struct task_struct *flush_thread = fcc->f2fs_issue_flush;
693 
694 		fcc->f2fs_issue_flush = NULL;
695 		kthread_stop(flush_thread);
696 	}
697 	if (free) {
698 		kfree(fcc);
699 		SM_I(sbi)->fcc_info = NULL;
700 	}
701 }
702 
703 int f2fs_flush_device_cache(struct f2fs_sb_info *sbi)
704 {
705 	int ret = 0, i;
706 
707 	if (!sbi->s_ndevs)
708 		return 0;
709 
710 	for (i = 1; i < sbi->s_ndevs; i++) {
711 		if (!f2fs_test_bit(i, (char *)&sbi->dirty_device))
712 			continue;
713 		ret = __submit_flush_wait(sbi, FDEV(i).bdev);
714 		if (ret)
715 			break;
716 
717 		spin_lock(&sbi->dev_lock);
718 		f2fs_clear_bit(i, (char *)&sbi->dirty_device);
719 		spin_unlock(&sbi->dev_lock);
720 	}
721 
722 	return ret;
723 }
724 
725 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
726 		enum dirty_type dirty_type)
727 {
728 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
729 
730 	/* need not be added */
731 	if (IS_CURSEG(sbi, segno))
732 		return;
733 
734 	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
735 		dirty_i->nr_dirty[dirty_type]++;
736 
737 	if (dirty_type == DIRTY) {
738 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
739 		enum dirty_type t = sentry->type;
740 
741 		if (unlikely(t >= DIRTY)) {
742 			f2fs_bug_on(sbi, 1);
743 			return;
744 		}
745 		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
746 			dirty_i->nr_dirty[t]++;
747 	}
748 }
749 
750 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
751 		enum dirty_type dirty_type)
752 {
753 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
754 
755 	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
756 		dirty_i->nr_dirty[dirty_type]--;
757 
758 	if (dirty_type == DIRTY) {
759 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
760 		enum dirty_type t = sentry->type;
761 
762 		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
763 			dirty_i->nr_dirty[t]--;
764 
765 		if (get_valid_blocks(sbi, segno, true) == 0)
766 			clear_bit(GET_SEC_FROM_SEG(sbi, segno),
767 						dirty_i->victim_secmap);
768 	}
769 }
770 
771 /*
772  * Should not occur error such as -ENOMEM.
773  * Adding dirty entry into seglist is not critical operation.
774  * If a given segment is one of current working segments, it won't be added.
775  */
776 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
777 {
778 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
779 	unsigned short valid_blocks;
780 
781 	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
782 		return;
783 
784 	mutex_lock(&dirty_i->seglist_lock);
785 
786 	valid_blocks = get_valid_blocks(sbi, segno, false);
787 
788 	if (valid_blocks == 0) {
789 		__locate_dirty_segment(sbi, segno, PRE);
790 		__remove_dirty_segment(sbi, segno, DIRTY);
791 	} else if (valid_blocks < sbi->blocks_per_seg) {
792 		__locate_dirty_segment(sbi, segno, DIRTY);
793 	} else {
794 		/* Recovery routine with SSR needs this */
795 		__remove_dirty_segment(sbi, segno, DIRTY);
796 	}
797 
798 	mutex_unlock(&dirty_i->seglist_lock);
799 }
800 
801 static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
802 		struct block_device *bdev, block_t lstart,
803 		block_t start, block_t len)
804 {
805 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
806 	struct list_head *pend_list;
807 	struct discard_cmd *dc;
808 
809 	f2fs_bug_on(sbi, !len);
810 
811 	pend_list = &dcc->pend_list[plist_idx(len)];
812 
813 	dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS);
814 	INIT_LIST_HEAD(&dc->list);
815 	dc->bdev = bdev;
816 	dc->lstart = lstart;
817 	dc->start = start;
818 	dc->len = len;
819 	dc->ref = 0;
820 	dc->state = D_PREP;
821 	dc->error = 0;
822 	init_completion(&dc->wait);
823 	list_add_tail(&dc->list, pend_list);
824 	atomic_inc(&dcc->discard_cmd_cnt);
825 	dcc->undiscard_blks += len;
826 
827 	return dc;
828 }
829 
830 static struct discard_cmd *__attach_discard_cmd(struct f2fs_sb_info *sbi,
831 				struct block_device *bdev, block_t lstart,
832 				block_t start, block_t len,
833 				struct rb_node *parent, struct rb_node **p)
834 {
835 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
836 	struct discard_cmd *dc;
837 
838 	dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
839 
840 	rb_link_node(&dc->rb_node, parent, p);
841 	rb_insert_color(&dc->rb_node, &dcc->root);
842 
843 	return dc;
844 }
845 
846 static void __detach_discard_cmd(struct discard_cmd_control *dcc,
847 							struct discard_cmd *dc)
848 {
849 	if (dc->state == D_DONE)
850 		atomic_dec(&dcc->issing_discard);
851 
852 	list_del(&dc->list);
853 	rb_erase(&dc->rb_node, &dcc->root);
854 	dcc->undiscard_blks -= dc->len;
855 
856 	kmem_cache_free(discard_cmd_slab, dc);
857 
858 	atomic_dec(&dcc->discard_cmd_cnt);
859 }
860 
861 static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
862 							struct discard_cmd *dc)
863 {
864 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
865 
866 	trace_f2fs_remove_discard(dc->bdev, dc->start, dc->len);
867 
868 	f2fs_bug_on(sbi, dc->ref);
869 
870 	if (dc->error == -EOPNOTSUPP)
871 		dc->error = 0;
872 
873 	if (dc->error)
874 		f2fs_msg(sbi->sb, KERN_INFO,
875 			"Issue discard(%u, %u, %u) failed, ret: %d",
876 			dc->lstart, dc->start, dc->len, dc->error);
877 	__detach_discard_cmd(dcc, dc);
878 }
879 
880 static void f2fs_submit_discard_endio(struct bio *bio)
881 {
882 	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
883 
884 	dc->error = blk_status_to_errno(bio->bi_status);
885 	dc->state = D_DONE;
886 	complete_all(&dc->wait);
887 	bio_put(bio);
888 }
889 
890 static void __check_sit_bitmap(struct f2fs_sb_info *sbi,
891 				block_t start, block_t end)
892 {
893 #ifdef CONFIG_F2FS_CHECK_FS
894 	struct seg_entry *sentry;
895 	unsigned int segno;
896 	block_t blk = start;
897 	unsigned long offset, size, max_blocks = sbi->blocks_per_seg;
898 	unsigned long *map;
899 
900 	while (blk < end) {
901 		segno = GET_SEGNO(sbi, blk);
902 		sentry = get_seg_entry(sbi, segno);
903 		offset = GET_BLKOFF_FROM_SEG0(sbi, blk);
904 
905 		if (end < START_BLOCK(sbi, segno + 1))
906 			size = GET_BLKOFF_FROM_SEG0(sbi, end);
907 		else
908 			size = max_blocks;
909 		map = (unsigned long *)(sentry->cur_valid_map);
910 		offset = __find_rev_next_bit(map, size, offset);
911 		f2fs_bug_on(sbi, offset != size);
912 		blk = START_BLOCK(sbi, segno + 1);
913 	}
914 #endif
915 }
916 
917 static void __init_discard_policy(struct f2fs_sb_info *sbi,
918 				struct discard_policy *dpolicy,
919 				int discard_type, unsigned int granularity)
920 {
921 	/* common policy */
922 	dpolicy->type = discard_type;
923 	dpolicy->sync = true;
924 	dpolicy->granularity = granularity;
925 
926 	dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
927 	dpolicy->io_aware_gran = MAX_PLIST_NUM;
928 
929 	if (discard_type == DPOLICY_BG) {
930 		dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
931 		dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
932 		dpolicy->io_aware = true;
933 		dpolicy->sync = false;
934 		if (utilization(sbi) > DEF_DISCARD_URGENT_UTIL) {
935 			dpolicy->granularity = 1;
936 			dpolicy->max_interval = DEF_MIN_DISCARD_ISSUE_TIME;
937 		}
938 	} else if (discard_type == DPOLICY_FORCE) {
939 		dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
940 		dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
941 		dpolicy->io_aware = false;
942 	} else if (discard_type == DPOLICY_FSTRIM) {
943 		dpolicy->io_aware = false;
944 	} else if (discard_type == DPOLICY_UMOUNT) {
945 		dpolicy->max_requests = UINT_MAX;
946 		dpolicy->io_aware = false;
947 	}
948 }
949 
950 
951 /* this function is copied from blkdev_issue_discard from block/blk-lib.c */
952 static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
953 						struct discard_policy *dpolicy,
954 						struct discard_cmd *dc)
955 {
956 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
957 	struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ?
958 					&(dcc->fstrim_list) : &(dcc->wait_list);
959 	struct bio *bio = NULL;
960 	int flag = dpolicy->sync ? REQ_SYNC : 0;
961 
962 	if (dc->state != D_PREP)
963 		return;
964 
965 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
966 		return;
967 
968 	trace_f2fs_issue_discard(dc->bdev, dc->start, dc->len);
969 
970 	dc->error = __blkdev_issue_discard(dc->bdev,
971 				SECTOR_FROM_BLOCK(dc->start),
972 				SECTOR_FROM_BLOCK(dc->len),
973 				GFP_NOFS, 0, &bio);
974 	if (!dc->error) {
975 		/* should keep before submission to avoid D_DONE right away */
976 		dc->state = D_SUBMIT;
977 		atomic_inc(&dcc->issued_discard);
978 		atomic_inc(&dcc->issing_discard);
979 		if (bio) {
980 			bio->bi_private = dc;
981 			bio->bi_end_io = f2fs_submit_discard_endio;
982 			bio->bi_opf |= flag;
983 			submit_bio(bio);
984 			list_move_tail(&dc->list, wait_list);
985 			__check_sit_bitmap(sbi, dc->start, dc->start + dc->len);
986 
987 			f2fs_update_iostat(sbi, FS_DISCARD, 1);
988 		}
989 	} else {
990 		__remove_discard_cmd(sbi, dc);
991 	}
992 }
993 
994 static struct discard_cmd *__insert_discard_tree(struct f2fs_sb_info *sbi,
995 				struct block_device *bdev, block_t lstart,
996 				block_t start, block_t len,
997 				struct rb_node **insert_p,
998 				struct rb_node *insert_parent)
999 {
1000 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1001 	struct rb_node **p;
1002 	struct rb_node *parent = NULL;
1003 	struct discard_cmd *dc = NULL;
1004 
1005 	if (insert_p && insert_parent) {
1006 		parent = insert_parent;
1007 		p = insert_p;
1008 		goto do_insert;
1009 	}
1010 
1011 	p = __lookup_rb_tree_for_insert(sbi, &dcc->root, &parent, lstart);
1012 do_insert:
1013 	dc = __attach_discard_cmd(sbi, bdev, lstart, start, len, parent, p);
1014 	if (!dc)
1015 		return NULL;
1016 
1017 	return dc;
1018 }
1019 
1020 static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
1021 						struct discard_cmd *dc)
1022 {
1023 	list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
1024 }
1025 
1026 static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
1027 				struct discard_cmd *dc, block_t blkaddr)
1028 {
1029 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1030 	struct discard_info di = dc->di;
1031 	bool modified = false;
1032 
1033 	if (dc->state == D_DONE || dc->len == 1) {
1034 		__remove_discard_cmd(sbi, dc);
1035 		return;
1036 	}
1037 
1038 	dcc->undiscard_blks -= di.len;
1039 
1040 	if (blkaddr > di.lstart) {
1041 		dc->len = blkaddr - dc->lstart;
1042 		dcc->undiscard_blks += dc->len;
1043 		__relocate_discard_cmd(dcc, dc);
1044 		modified = true;
1045 	}
1046 
1047 	if (blkaddr < di.lstart + di.len - 1) {
1048 		if (modified) {
1049 			__insert_discard_tree(sbi, dc->bdev, blkaddr + 1,
1050 					di.start + blkaddr + 1 - di.lstart,
1051 					di.lstart + di.len - 1 - blkaddr,
1052 					NULL, NULL);
1053 		} else {
1054 			dc->lstart++;
1055 			dc->len--;
1056 			dc->start++;
1057 			dcc->undiscard_blks += dc->len;
1058 			__relocate_discard_cmd(dcc, dc);
1059 		}
1060 	}
1061 }
1062 
1063 static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
1064 				struct block_device *bdev, block_t lstart,
1065 				block_t start, block_t len)
1066 {
1067 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1068 	struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
1069 	struct discard_cmd *dc;
1070 	struct discard_info di = {0};
1071 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
1072 	block_t end = lstart + len;
1073 
1074 	mutex_lock(&dcc->cmd_lock);
1075 
1076 	dc = (struct discard_cmd *)__lookup_rb_tree_ret(&dcc->root,
1077 					NULL, lstart,
1078 					(struct rb_entry **)&prev_dc,
1079 					(struct rb_entry **)&next_dc,
1080 					&insert_p, &insert_parent, true);
1081 	if (dc)
1082 		prev_dc = dc;
1083 
1084 	if (!prev_dc) {
1085 		di.lstart = lstart;
1086 		di.len = next_dc ? next_dc->lstart - lstart : len;
1087 		di.len = min(di.len, len);
1088 		di.start = start;
1089 	}
1090 
1091 	while (1) {
1092 		struct rb_node *node;
1093 		bool merged = false;
1094 		struct discard_cmd *tdc = NULL;
1095 
1096 		if (prev_dc) {
1097 			di.lstart = prev_dc->lstart + prev_dc->len;
1098 			if (di.lstart < lstart)
1099 				di.lstart = lstart;
1100 			if (di.lstart >= end)
1101 				break;
1102 
1103 			if (!next_dc || next_dc->lstart > end)
1104 				di.len = end - di.lstart;
1105 			else
1106 				di.len = next_dc->lstart - di.lstart;
1107 			di.start = start + di.lstart - lstart;
1108 		}
1109 
1110 		if (!di.len)
1111 			goto next;
1112 
1113 		if (prev_dc && prev_dc->state == D_PREP &&
1114 			prev_dc->bdev == bdev &&
1115 			__is_discard_back_mergeable(&di, &prev_dc->di)) {
1116 			prev_dc->di.len += di.len;
1117 			dcc->undiscard_blks += di.len;
1118 			__relocate_discard_cmd(dcc, prev_dc);
1119 			di = prev_dc->di;
1120 			tdc = prev_dc;
1121 			merged = true;
1122 		}
1123 
1124 		if (next_dc && next_dc->state == D_PREP &&
1125 			next_dc->bdev == bdev &&
1126 			__is_discard_front_mergeable(&di, &next_dc->di)) {
1127 			next_dc->di.lstart = di.lstart;
1128 			next_dc->di.len += di.len;
1129 			next_dc->di.start = di.start;
1130 			dcc->undiscard_blks += di.len;
1131 			__relocate_discard_cmd(dcc, next_dc);
1132 			if (tdc)
1133 				__remove_discard_cmd(sbi, tdc);
1134 			merged = true;
1135 		}
1136 
1137 		if (!merged) {
1138 			__insert_discard_tree(sbi, bdev, di.lstart, di.start,
1139 							di.len, NULL, NULL);
1140 		}
1141  next:
1142 		prev_dc = next_dc;
1143 		if (!prev_dc)
1144 			break;
1145 
1146 		node = rb_next(&prev_dc->rb_node);
1147 		next_dc = rb_entry_safe(node, struct discard_cmd, rb_node);
1148 	}
1149 
1150 	mutex_unlock(&dcc->cmd_lock);
1151 }
1152 
1153 static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
1154 		struct block_device *bdev, block_t blkstart, block_t blklen)
1155 {
1156 	block_t lblkstart = blkstart;
1157 
1158 	trace_f2fs_queue_discard(bdev, blkstart, blklen);
1159 
1160 	if (sbi->s_ndevs) {
1161 		int devi = f2fs_target_device_index(sbi, blkstart);
1162 
1163 		blkstart -= FDEV(devi).start_blk;
1164 	}
1165 	__update_discard_tree_range(sbi, bdev, lblkstart, blkstart, blklen);
1166 	return 0;
1167 }
1168 
1169 static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
1170 					struct discard_policy *dpolicy)
1171 {
1172 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1173 	struct list_head *pend_list;
1174 	struct discard_cmd *dc, *tmp;
1175 	struct blk_plug plug;
1176 	int i, iter = 0, issued = 0;
1177 	bool io_interrupted = false;
1178 
1179 	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
1180 		if (i + 1 < dpolicy->granularity)
1181 			break;
1182 		pend_list = &dcc->pend_list[i];
1183 
1184 		mutex_lock(&dcc->cmd_lock);
1185 		if (list_empty(pend_list))
1186 			goto next;
1187 		f2fs_bug_on(sbi, !__check_rb_tree_consistence(sbi, &dcc->root));
1188 		blk_start_plug(&plug);
1189 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
1190 			f2fs_bug_on(sbi, dc->state != D_PREP);
1191 
1192 			if (dpolicy->io_aware && i < dpolicy->io_aware_gran &&
1193 								!is_idle(sbi)) {
1194 				io_interrupted = true;
1195 				goto skip;
1196 			}
1197 
1198 			__submit_discard_cmd(sbi, dpolicy, dc);
1199 			issued++;
1200 skip:
1201 			if (++iter >= dpolicy->max_requests)
1202 				break;
1203 		}
1204 		blk_finish_plug(&plug);
1205 next:
1206 		mutex_unlock(&dcc->cmd_lock);
1207 
1208 		if (iter >= dpolicy->max_requests)
1209 			break;
1210 	}
1211 
1212 	if (!issued && io_interrupted)
1213 		issued = -1;
1214 
1215 	return issued;
1216 }
1217 
1218 static bool __drop_discard_cmd(struct f2fs_sb_info *sbi)
1219 {
1220 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1221 	struct list_head *pend_list;
1222 	struct discard_cmd *dc, *tmp;
1223 	int i;
1224 	bool dropped = false;
1225 
1226 	mutex_lock(&dcc->cmd_lock);
1227 	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
1228 		pend_list = &dcc->pend_list[i];
1229 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
1230 			f2fs_bug_on(sbi, dc->state != D_PREP);
1231 			__remove_discard_cmd(sbi, dc);
1232 			dropped = true;
1233 		}
1234 	}
1235 	mutex_unlock(&dcc->cmd_lock);
1236 
1237 	return dropped;
1238 }
1239 
1240 void drop_discard_cmd(struct f2fs_sb_info *sbi)
1241 {
1242 	__drop_discard_cmd(sbi);
1243 }
1244 
1245 static unsigned int __wait_one_discard_bio(struct f2fs_sb_info *sbi,
1246 							struct discard_cmd *dc)
1247 {
1248 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1249 	unsigned int len = 0;
1250 
1251 	wait_for_completion_io(&dc->wait);
1252 	mutex_lock(&dcc->cmd_lock);
1253 	f2fs_bug_on(sbi, dc->state != D_DONE);
1254 	dc->ref--;
1255 	if (!dc->ref) {
1256 		if (!dc->error)
1257 			len = dc->len;
1258 		__remove_discard_cmd(sbi, dc);
1259 	}
1260 	mutex_unlock(&dcc->cmd_lock);
1261 
1262 	return len;
1263 }
1264 
1265 static unsigned int __wait_discard_cmd_range(struct f2fs_sb_info *sbi,
1266 						struct discard_policy *dpolicy,
1267 						block_t start, block_t end)
1268 {
1269 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1270 	struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ?
1271 					&(dcc->fstrim_list) : &(dcc->wait_list);
1272 	struct discard_cmd *dc, *tmp;
1273 	bool need_wait;
1274 	unsigned int trimmed = 0;
1275 
1276 next:
1277 	need_wait = false;
1278 
1279 	mutex_lock(&dcc->cmd_lock);
1280 	list_for_each_entry_safe(dc, tmp, wait_list, list) {
1281 		if (dc->lstart + dc->len <= start || end <= dc->lstart)
1282 			continue;
1283 		if (dc->len < dpolicy->granularity)
1284 			continue;
1285 		if (dc->state == D_DONE && !dc->ref) {
1286 			wait_for_completion_io(&dc->wait);
1287 			if (!dc->error)
1288 				trimmed += dc->len;
1289 			__remove_discard_cmd(sbi, dc);
1290 		} else {
1291 			dc->ref++;
1292 			need_wait = true;
1293 			break;
1294 		}
1295 	}
1296 	mutex_unlock(&dcc->cmd_lock);
1297 
1298 	if (need_wait) {
1299 		trimmed += __wait_one_discard_bio(sbi, dc);
1300 		goto next;
1301 	}
1302 
1303 	return trimmed;
1304 }
1305 
1306 static void __wait_all_discard_cmd(struct f2fs_sb_info *sbi,
1307 						struct discard_policy *dpolicy)
1308 {
1309 	struct discard_policy dp;
1310 
1311 	if (dpolicy) {
1312 		__wait_discard_cmd_range(sbi, dpolicy, 0, UINT_MAX);
1313 		return;
1314 	}
1315 
1316 	/* wait all */
1317 	__init_discard_policy(sbi, &dp, DPOLICY_FSTRIM, 1);
1318 	__wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX);
1319 	__init_discard_policy(sbi, &dp, DPOLICY_UMOUNT, 1);
1320 	__wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX);
1321 }
1322 
1323 /* This should be covered by global mutex, &sit_i->sentry_lock */
1324 static void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
1325 {
1326 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1327 	struct discard_cmd *dc;
1328 	bool need_wait = false;
1329 
1330 	mutex_lock(&dcc->cmd_lock);
1331 	dc = (struct discard_cmd *)__lookup_rb_tree(&dcc->root, NULL, blkaddr);
1332 	if (dc) {
1333 		if (dc->state == D_PREP) {
1334 			__punch_discard_cmd(sbi, dc, blkaddr);
1335 		} else {
1336 			dc->ref++;
1337 			need_wait = true;
1338 		}
1339 	}
1340 	mutex_unlock(&dcc->cmd_lock);
1341 
1342 	if (need_wait)
1343 		__wait_one_discard_bio(sbi, dc);
1344 }
1345 
1346 void stop_discard_thread(struct f2fs_sb_info *sbi)
1347 {
1348 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1349 
1350 	if (dcc && dcc->f2fs_issue_discard) {
1351 		struct task_struct *discard_thread = dcc->f2fs_issue_discard;
1352 
1353 		dcc->f2fs_issue_discard = NULL;
1354 		kthread_stop(discard_thread);
1355 	}
1356 }
1357 
1358 /* This comes from f2fs_put_super */
1359 bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
1360 {
1361 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1362 	struct discard_policy dpolicy;
1363 	bool dropped;
1364 
1365 	__init_discard_policy(sbi, &dpolicy, DPOLICY_UMOUNT,
1366 					dcc->discard_granularity);
1367 	__issue_discard_cmd(sbi, &dpolicy);
1368 	dropped = __drop_discard_cmd(sbi);
1369 
1370 	/* just to make sure there is no pending discard commands */
1371 	__wait_all_discard_cmd(sbi, NULL);
1372 	return dropped;
1373 }
1374 
1375 static int issue_discard_thread(void *data)
1376 {
1377 	struct f2fs_sb_info *sbi = data;
1378 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1379 	wait_queue_head_t *q = &dcc->discard_wait_queue;
1380 	struct discard_policy dpolicy;
1381 	unsigned int wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
1382 	int issued;
1383 
1384 	set_freezable();
1385 
1386 	do {
1387 		__init_discard_policy(sbi, &dpolicy, DPOLICY_BG,
1388 					dcc->discard_granularity);
1389 
1390 		wait_event_interruptible_timeout(*q,
1391 				kthread_should_stop() || freezing(current) ||
1392 				dcc->discard_wake,
1393 				msecs_to_jiffies(wait_ms));
1394 		if (try_to_freeze())
1395 			continue;
1396 		if (f2fs_readonly(sbi->sb))
1397 			continue;
1398 		if (kthread_should_stop())
1399 			return 0;
1400 		if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
1401 			wait_ms = dpolicy.max_interval;
1402 			continue;
1403 		}
1404 
1405 		if (dcc->discard_wake)
1406 			dcc->discard_wake = 0;
1407 
1408 		if (sbi->gc_mode == GC_URGENT)
1409 			__init_discard_policy(sbi, &dpolicy, DPOLICY_FORCE, 1);
1410 
1411 		sb_start_intwrite(sbi->sb);
1412 
1413 		issued = __issue_discard_cmd(sbi, &dpolicy);
1414 		if (issued) {
1415 			__wait_all_discard_cmd(sbi, &dpolicy);
1416 			wait_ms = dpolicy.min_interval;
1417 		} else {
1418 			wait_ms = dpolicy.max_interval;
1419 		}
1420 
1421 		sb_end_intwrite(sbi->sb);
1422 
1423 	} while (!kthread_should_stop());
1424 	return 0;
1425 }
1426 
1427 #ifdef CONFIG_BLK_DEV_ZONED
1428 static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
1429 		struct block_device *bdev, block_t blkstart, block_t blklen)
1430 {
1431 	sector_t sector, nr_sects;
1432 	block_t lblkstart = blkstart;
1433 	int devi = 0;
1434 
1435 	if (sbi->s_ndevs) {
1436 		devi = f2fs_target_device_index(sbi, blkstart);
1437 		blkstart -= FDEV(devi).start_blk;
1438 	}
1439 
1440 	/*
1441 	 * We need to know the type of the zone: for conventional zones,
1442 	 * use regular discard if the drive supports it. For sequential
1443 	 * zones, reset the zone write pointer.
1444 	 */
1445 	switch (get_blkz_type(sbi, bdev, blkstart)) {
1446 
1447 	case BLK_ZONE_TYPE_CONVENTIONAL:
1448 		if (!blk_queue_discard(bdev_get_queue(bdev)))
1449 			return 0;
1450 		return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
1451 	case BLK_ZONE_TYPE_SEQWRITE_REQ:
1452 	case BLK_ZONE_TYPE_SEQWRITE_PREF:
1453 		sector = SECTOR_FROM_BLOCK(blkstart);
1454 		nr_sects = SECTOR_FROM_BLOCK(blklen);
1455 
1456 		if (sector & (bdev_zone_sectors(bdev) - 1) ||
1457 				nr_sects != bdev_zone_sectors(bdev)) {
1458 			f2fs_msg(sbi->sb, KERN_INFO,
1459 				"(%d) %s: Unaligned discard attempted (block %x + %x)",
1460 				devi, sbi->s_ndevs ? FDEV(devi).path: "",
1461 				blkstart, blklen);
1462 			return -EIO;
1463 		}
1464 		trace_f2fs_issue_reset_zone(bdev, blkstart);
1465 		return blkdev_reset_zones(bdev, sector,
1466 					  nr_sects, GFP_NOFS);
1467 	default:
1468 		/* Unknown zone type: broken device ? */
1469 		return -EIO;
1470 	}
1471 }
1472 #endif
1473 
1474 static int __issue_discard_async(struct f2fs_sb_info *sbi,
1475 		struct block_device *bdev, block_t blkstart, block_t blklen)
1476 {
1477 #ifdef CONFIG_BLK_DEV_ZONED
1478 	if (f2fs_sb_has_blkzoned(sbi->sb) &&
1479 				bdev_zoned_model(bdev) != BLK_ZONED_NONE)
1480 		return __f2fs_issue_discard_zone(sbi, bdev, blkstart, blklen);
1481 #endif
1482 	return __queue_discard_cmd(sbi, bdev, blkstart, blklen);
1483 }
1484 
1485 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
1486 				block_t blkstart, block_t blklen)
1487 {
1488 	sector_t start = blkstart, len = 0;
1489 	struct block_device *bdev;
1490 	struct seg_entry *se;
1491 	unsigned int offset;
1492 	block_t i;
1493 	int err = 0;
1494 
1495 	bdev = f2fs_target_device(sbi, blkstart, NULL);
1496 
1497 	for (i = blkstart; i < blkstart + blklen; i++, len++) {
1498 		if (i != start) {
1499 			struct block_device *bdev2 =
1500 				f2fs_target_device(sbi, i, NULL);
1501 
1502 			if (bdev2 != bdev) {
1503 				err = __issue_discard_async(sbi, bdev,
1504 						start, len);
1505 				if (err)
1506 					return err;
1507 				bdev = bdev2;
1508 				start = i;
1509 				len = 0;
1510 			}
1511 		}
1512 
1513 		se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
1514 		offset = GET_BLKOFF_FROM_SEG0(sbi, i);
1515 
1516 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
1517 			sbi->discard_blks--;
1518 	}
1519 
1520 	if (len)
1521 		err = __issue_discard_async(sbi, bdev, start, len);
1522 	return err;
1523 }
1524 
1525 static bool add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc,
1526 							bool check_only)
1527 {
1528 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1529 	int max_blocks = sbi->blocks_per_seg;
1530 	struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
1531 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1532 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1533 	unsigned long *discard_map = (unsigned long *)se->discard_map;
1534 	unsigned long *dmap = SIT_I(sbi)->tmp_map;
1535 	unsigned int start = 0, end = -1;
1536 	bool force = (cpc->reason & CP_DISCARD);
1537 	struct discard_entry *de = NULL;
1538 	struct list_head *head = &SM_I(sbi)->dcc_info->entry_list;
1539 	int i;
1540 
1541 	if (se->valid_blocks == max_blocks || !f2fs_discard_en(sbi))
1542 		return false;
1543 
1544 	if (!force) {
1545 		if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
1546 			SM_I(sbi)->dcc_info->nr_discards >=
1547 				SM_I(sbi)->dcc_info->max_discards)
1548 			return false;
1549 	}
1550 
1551 	/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
1552 	for (i = 0; i < entries; i++)
1553 		dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
1554 				(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
1555 
1556 	while (force || SM_I(sbi)->dcc_info->nr_discards <=
1557 				SM_I(sbi)->dcc_info->max_discards) {
1558 		start = __find_rev_next_bit(dmap, max_blocks, end + 1);
1559 		if (start >= max_blocks)
1560 			break;
1561 
1562 		end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
1563 		if (force && start && end != max_blocks
1564 					&& (end - start) < cpc->trim_minlen)
1565 			continue;
1566 
1567 		if (check_only)
1568 			return true;
1569 
1570 		if (!de) {
1571 			de = f2fs_kmem_cache_alloc(discard_entry_slab,
1572 								GFP_F2FS_ZERO);
1573 			de->start_blkaddr = START_BLOCK(sbi, cpc->trim_start);
1574 			list_add_tail(&de->list, head);
1575 		}
1576 
1577 		for (i = start; i < end; i++)
1578 			__set_bit_le(i, (void *)de->discard_map);
1579 
1580 		SM_I(sbi)->dcc_info->nr_discards += end - start;
1581 	}
1582 	return false;
1583 }
1584 
1585 static void release_discard_addr(struct discard_entry *entry)
1586 {
1587 	list_del(&entry->list);
1588 	kmem_cache_free(discard_entry_slab, entry);
1589 }
1590 
1591 void release_discard_addrs(struct f2fs_sb_info *sbi)
1592 {
1593 	struct list_head *head = &(SM_I(sbi)->dcc_info->entry_list);
1594 	struct discard_entry *entry, *this;
1595 
1596 	/* drop caches */
1597 	list_for_each_entry_safe(entry, this, head, list)
1598 		release_discard_addr(entry);
1599 }
1600 
1601 /*
1602  * Should call clear_prefree_segments after checkpoint is done.
1603  */
1604 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
1605 {
1606 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1607 	unsigned int segno;
1608 
1609 	mutex_lock(&dirty_i->seglist_lock);
1610 	for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
1611 		__set_test_and_free(sbi, segno);
1612 	mutex_unlock(&dirty_i->seglist_lock);
1613 }
1614 
1615 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1616 {
1617 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1618 	struct list_head *head = &dcc->entry_list;
1619 	struct discard_entry *entry, *this;
1620 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1621 	unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
1622 	unsigned int start = 0, end = -1;
1623 	unsigned int secno, start_segno;
1624 	bool force = (cpc->reason & CP_DISCARD);
1625 
1626 	mutex_lock(&dirty_i->seglist_lock);
1627 
1628 	while (1) {
1629 		int i;
1630 		start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
1631 		if (start >= MAIN_SEGS(sbi))
1632 			break;
1633 		end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
1634 								start + 1);
1635 
1636 		for (i = start; i < end; i++)
1637 			clear_bit(i, prefree_map);
1638 
1639 		dirty_i->nr_dirty[PRE] -= end - start;
1640 
1641 		if (!test_opt(sbi, DISCARD))
1642 			continue;
1643 
1644 		if (force && start >= cpc->trim_start &&
1645 					(end - 1) <= cpc->trim_end)
1646 				continue;
1647 
1648 		if (!test_opt(sbi, LFS) || sbi->segs_per_sec == 1) {
1649 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
1650 				(end - start) << sbi->log_blocks_per_seg);
1651 			continue;
1652 		}
1653 next:
1654 		secno = GET_SEC_FROM_SEG(sbi, start);
1655 		start_segno = GET_SEG_FROM_SEC(sbi, secno);
1656 		if (!IS_CURSEC(sbi, secno) &&
1657 			!get_valid_blocks(sbi, start, true))
1658 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start_segno),
1659 				sbi->segs_per_sec << sbi->log_blocks_per_seg);
1660 
1661 		start = start_segno + sbi->segs_per_sec;
1662 		if (start < end)
1663 			goto next;
1664 		else
1665 			end = start - 1;
1666 	}
1667 	mutex_unlock(&dirty_i->seglist_lock);
1668 
1669 	/* send small discards */
1670 	list_for_each_entry_safe(entry, this, head, list) {
1671 		unsigned int cur_pos = 0, next_pos, len, total_len = 0;
1672 		bool is_valid = test_bit_le(0, entry->discard_map);
1673 
1674 find_next:
1675 		if (is_valid) {
1676 			next_pos = find_next_zero_bit_le(entry->discard_map,
1677 					sbi->blocks_per_seg, cur_pos);
1678 			len = next_pos - cur_pos;
1679 
1680 			if (f2fs_sb_has_blkzoned(sbi->sb) ||
1681 			    (force && len < cpc->trim_minlen))
1682 				goto skip;
1683 
1684 			f2fs_issue_discard(sbi, entry->start_blkaddr + cur_pos,
1685 									len);
1686 			total_len += len;
1687 		} else {
1688 			next_pos = find_next_bit_le(entry->discard_map,
1689 					sbi->blocks_per_seg, cur_pos);
1690 		}
1691 skip:
1692 		cur_pos = next_pos;
1693 		is_valid = !is_valid;
1694 
1695 		if (cur_pos < sbi->blocks_per_seg)
1696 			goto find_next;
1697 
1698 		release_discard_addr(entry);
1699 		dcc->nr_discards -= total_len;
1700 	}
1701 
1702 	wake_up_discard_thread(sbi, false);
1703 }
1704 
1705 static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
1706 {
1707 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1708 	struct discard_cmd_control *dcc;
1709 	int err = 0, i;
1710 
1711 	if (SM_I(sbi)->dcc_info) {
1712 		dcc = SM_I(sbi)->dcc_info;
1713 		goto init_thread;
1714 	}
1715 
1716 	dcc = f2fs_kzalloc(sbi, sizeof(struct discard_cmd_control), GFP_KERNEL);
1717 	if (!dcc)
1718 		return -ENOMEM;
1719 
1720 	dcc->discard_granularity = DEFAULT_DISCARD_GRANULARITY;
1721 	INIT_LIST_HEAD(&dcc->entry_list);
1722 	for (i = 0; i < MAX_PLIST_NUM; i++)
1723 		INIT_LIST_HEAD(&dcc->pend_list[i]);
1724 	INIT_LIST_HEAD(&dcc->wait_list);
1725 	INIT_LIST_HEAD(&dcc->fstrim_list);
1726 	mutex_init(&dcc->cmd_lock);
1727 	atomic_set(&dcc->issued_discard, 0);
1728 	atomic_set(&dcc->issing_discard, 0);
1729 	atomic_set(&dcc->discard_cmd_cnt, 0);
1730 	dcc->nr_discards = 0;
1731 	dcc->max_discards = MAIN_SEGS(sbi) << sbi->log_blocks_per_seg;
1732 	dcc->undiscard_blks = 0;
1733 	dcc->root = RB_ROOT;
1734 
1735 	init_waitqueue_head(&dcc->discard_wait_queue);
1736 	SM_I(sbi)->dcc_info = dcc;
1737 init_thread:
1738 	dcc->f2fs_issue_discard = kthread_run(issue_discard_thread, sbi,
1739 				"f2fs_discard-%u:%u", MAJOR(dev), MINOR(dev));
1740 	if (IS_ERR(dcc->f2fs_issue_discard)) {
1741 		err = PTR_ERR(dcc->f2fs_issue_discard);
1742 		kfree(dcc);
1743 		SM_I(sbi)->dcc_info = NULL;
1744 		return err;
1745 	}
1746 
1747 	return err;
1748 }
1749 
1750 static void destroy_discard_cmd_control(struct f2fs_sb_info *sbi)
1751 {
1752 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1753 
1754 	if (!dcc)
1755 		return;
1756 
1757 	stop_discard_thread(sbi);
1758 
1759 	kfree(dcc);
1760 	SM_I(sbi)->dcc_info = NULL;
1761 }
1762 
1763 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
1764 {
1765 	struct sit_info *sit_i = SIT_I(sbi);
1766 
1767 	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
1768 		sit_i->dirty_sentries++;
1769 		return false;
1770 	}
1771 
1772 	return true;
1773 }
1774 
1775 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
1776 					unsigned int segno, int modified)
1777 {
1778 	struct seg_entry *se = get_seg_entry(sbi, segno);
1779 	se->type = type;
1780 	if (modified)
1781 		__mark_sit_entry_dirty(sbi, segno);
1782 }
1783 
1784 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
1785 {
1786 	struct seg_entry *se;
1787 	unsigned int segno, offset;
1788 	long int new_vblocks;
1789 	bool exist;
1790 #ifdef CONFIG_F2FS_CHECK_FS
1791 	bool mir_exist;
1792 #endif
1793 
1794 	segno = GET_SEGNO(sbi, blkaddr);
1795 
1796 	se = get_seg_entry(sbi, segno);
1797 	new_vblocks = se->valid_blocks + del;
1798 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1799 
1800 	f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
1801 				(new_vblocks > sbi->blocks_per_seg)));
1802 
1803 	se->valid_blocks = new_vblocks;
1804 	se->mtime = get_mtime(sbi);
1805 	SIT_I(sbi)->max_mtime = se->mtime;
1806 
1807 	/* Update valid block bitmap */
1808 	if (del > 0) {
1809 		exist = f2fs_test_and_set_bit(offset, se->cur_valid_map);
1810 #ifdef CONFIG_F2FS_CHECK_FS
1811 		mir_exist = f2fs_test_and_set_bit(offset,
1812 						se->cur_valid_map_mir);
1813 		if (unlikely(exist != mir_exist)) {
1814 			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
1815 				"when setting bitmap, blk:%u, old bit:%d",
1816 				blkaddr, exist);
1817 			f2fs_bug_on(sbi, 1);
1818 		}
1819 #endif
1820 		if (unlikely(exist)) {
1821 			f2fs_msg(sbi->sb, KERN_ERR,
1822 				"Bitmap was wrongly set, blk:%u", blkaddr);
1823 			f2fs_bug_on(sbi, 1);
1824 			se->valid_blocks--;
1825 			del = 0;
1826 		}
1827 
1828 		if (f2fs_discard_en(sbi) &&
1829 			!f2fs_test_and_set_bit(offset, se->discard_map))
1830 			sbi->discard_blks--;
1831 
1832 		/* don't overwrite by SSR to keep node chain */
1833 		if (IS_NODESEG(se->type)) {
1834 			if (!f2fs_test_and_set_bit(offset, se->ckpt_valid_map))
1835 				se->ckpt_valid_blocks++;
1836 		}
1837 	} else {
1838 		exist = f2fs_test_and_clear_bit(offset, se->cur_valid_map);
1839 #ifdef CONFIG_F2FS_CHECK_FS
1840 		mir_exist = f2fs_test_and_clear_bit(offset,
1841 						se->cur_valid_map_mir);
1842 		if (unlikely(exist != mir_exist)) {
1843 			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
1844 				"when clearing bitmap, blk:%u, old bit:%d",
1845 				blkaddr, exist);
1846 			f2fs_bug_on(sbi, 1);
1847 		}
1848 #endif
1849 		if (unlikely(!exist)) {
1850 			f2fs_msg(sbi->sb, KERN_ERR,
1851 				"Bitmap was wrongly cleared, blk:%u", blkaddr);
1852 			f2fs_bug_on(sbi, 1);
1853 			se->valid_blocks++;
1854 			del = 0;
1855 		}
1856 
1857 		if (f2fs_discard_en(sbi) &&
1858 			f2fs_test_and_clear_bit(offset, se->discard_map))
1859 			sbi->discard_blks++;
1860 	}
1861 	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
1862 		se->ckpt_valid_blocks += del;
1863 
1864 	__mark_sit_entry_dirty(sbi, segno);
1865 
1866 	/* update total number of valid blocks to be written in ckpt area */
1867 	SIT_I(sbi)->written_valid_blocks += del;
1868 
1869 	if (sbi->segs_per_sec > 1)
1870 		get_sec_entry(sbi, segno)->valid_blocks += del;
1871 }
1872 
1873 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
1874 {
1875 	unsigned int segno = GET_SEGNO(sbi, addr);
1876 	struct sit_info *sit_i = SIT_I(sbi);
1877 
1878 	f2fs_bug_on(sbi, addr == NULL_ADDR);
1879 	if (addr == NEW_ADDR)
1880 		return;
1881 
1882 	/* add it into sit main buffer */
1883 	down_write(&sit_i->sentry_lock);
1884 
1885 	update_sit_entry(sbi, addr, -1);
1886 
1887 	/* add it into dirty seglist */
1888 	locate_dirty_segment(sbi, segno);
1889 
1890 	up_write(&sit_i->sentry_lock);
1891 }
1892 
1893 bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
1894 {
1895 	struct sit_info *sit_i = SIT_I(sbi);
1896 	unsigned int segno, offset;
1897 	struct seg_entry *se;
1898 	bool is_cp = false;
1899 
1900 	if (!is_valid_blkaddr(blkaddr))
1901 		return true;
1902 
1903 	down_read(&sit_i->sentry_lock);
1904 
1905 	segno = GET_SEGNO(sbi, blkaddr);
1906 	se = get_seg_entry(sbi, segno);
1907 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1908 
1909 	if (f2fs_test_bit(offset, se->ckpt_valid_map))
1910 		is_cp = true;
1911 
1912 	up_read(&sit_i->sentry_lock);
1913 
1914 	return is_cp;
1915 }
1916 
1917 /*
1918  * This function should be resided under the curseg_mutex lock
1919  */
1920 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
1921 					struct f2fs_summary *sum)
1922 {
1923 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1924 	void *addr = curseg->sum_blk;
1925 	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
1926 	memcpy(addr, sum, sizeof(struct f2fs_summary));
1927 }
1928 
1929 /*
1930  * Calculate the number of current summary pages for writing
1931  */
1932 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
1933 {
1934 	int valid_sum_count = 0;
1935 	int i, sum_in_page;
1936 
1937 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1938 		if (sbi->ckpt->alloc_type[i] == SSR)
1939 			valid_sum_count += sbi->blocks_per_seg;
1940 		else {
1941 			if (for_ra)
1942 				valid_sum_count += le16_to_cpu(
1943 					F2FS_CKPT(sbi)->cur_data_blkoff[i]);
1944 			else
1945 				valid_sum_count += curseg_blkoff(sbi, i);
1946 		}
1947 	}
1948 
1949 	sum_in_page = (PAGE_SIZE - 2 * SUM_JOURNAL_SIZE -
1950 			SUM_FOOTER_SIZE) / SUMMARY_SIZE;
1951 	if (valid_sum_count <= sum_in_page)
1952 		return 1;
1953 	else if ((valid_sum_count - sum_in_page) <=
1954 		(PAGE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
1955 		return 2;
1956 	return 3;
1957 }
1958 
1959 /*
1960  * Caller should put this summary page
1961  */
1962 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
1963 {
1964 	return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
1965 }
1966 
1967 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr)
1968 {
1969 	struct page *page = grab_meta_page(sbi, blk_addr);
1970 
1971 	memcpy(page_address(page), src, PAGE_SIZE);
1972 	set_page_dirty(page);
1973 	f2fs_put_page(page, 1);
1974 }
1975 
1976 static void write_sum_page(struct f2fs_sb_info *sbi,
1977 			struct f2fs_summary_block *sum_blk, block_t blk_addr)
1978 {
1979 	update_meta_page(sbi, (void *)sum_blk, blk_addr);
1980 }
1981 
1982 static void write_current_sum_page(struct f2fs_sb_info *sbi,
1983 						int type, block_t blk_addr)
1984 {
1985 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1986 	struct page *page = grab_meta_page(sbi, blk_addr);
1987 	struct f2fs_summary_block *src = curseg->sum_blk;
1988 	struct f2fs_summary_block *dst;
1989 
1990 	dst = (struct f2fs_summary_block *)page_address(page);
1991 	memset(dst, 0, PAGE_SIZE);
1992 
1993 	mutex_lock(&curseg->curseg_mutex);
1994 
1995 	down_read(&curseg->journal_rwsem);
1996 	memcpy(&dst->journal, curseg->journal, SUM_JOURNAL_SIZE);
1997 	up_read(&curseg->journal_rwsem);
1998 
1999 	memcpy(dst->entries, src->entries, SUM_ENTRY_SIZE);
2000 	memcpy(&dst->footer, &src->footer, SUM_FOOTER_SIZE);
2001 
2002 	mutex_unlock(&curseg->curseg_mutex);
2003 
2004 	set_page_dirty(page);
2005 	f2fs_put_page(page, 1);
2006 }
2007 
2008 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
2009 {
2010 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2011 	unsigned int segno = curseg->segno + 1;
2012 	struct free_segmap_info *free_i = FREE_I(sbi);
2013 
2014 	if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
2015 		return !test_bit(segno, free_i->free_segmap);
2016 	return 0;
2017 }
2018 
2019 /*
2020  * Find a new segment from the free segments bitmap to right order
2021  * This function should be returned with success, otherwise BUG
2022  */
2023 static void get_new_segment(struct f2fs_sb_info *sbi,
2024 			unsigned int *newseg, bool new_sec, int dir)
2025 {
2026 	struct free_segmap_info *free_i = FREE_I(sbi);
2027 	unsigned int segno, secno, zoneno;
2028 	unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
2029 	unsigned int hint = GET_SEC_FROM_SEG(sbi, *newseg);
2030 	unsigned int old_zoneno = GET_ZONE_FROM_SEG(sbi, *newseg);
2031 	unsigned int left_start = hint;
2032 	bool init = true;
2033 	int go_left = 0;
2034 	int i;
2035 
2036 	spin_lock(&free_i->segmap_lock);
2037 
2038 	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
2039 		segno = find_next_zero_bit(free_i->free_segmap,
2040 			GET_SEG_FROM_SEC(sbi, hint + 1), *newseg + 1);
2041 		if (segno < GET_SEG_FROM_SEC(sbi, hint + 1))
2042 			goto got_it;
2043 	}
2044 find_other_zone:
2045 	secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
2046 	if (secno >= MAIN_SECS(sbi)) {
2047 		if (dir == ALLOC_RIGHT) {
2048 			secno = find_next_zero_bit(free_i->free_secmap,
2049 							MAIN_SECS(sbi), 0);
2050 			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
2051 		} else {
2052 			go_left = 1;
2053 			left_start = hint - 1;
2054 		}
2055 	}
2056 	if (go_left == 0)
2057 		goto skip_left;
2058 
2059 	while (test_bit(left_start, free_i->free_secmap)) {
2060 		if (left_start > 0) {
2061 			left_start--;
2062 			continue;
2063 		}
2064 		left_start = find_next_zero_bit(free_i->free_secmap,
2065 							MAIN_SECS(sbi), 0);
2066 		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
2067 		break;
2068 	}
2069 	secno = left_start;
2070 skip_left:
2071 	segno = GET_SEG_FROM_SEC(sbi, secno);
2072 	zoneno = GET_ZONE_FROM_SEC(sbi, secno);
2073 
2074 	/* give up on finding another zone */
2075 	if (!init)
2076 		goto got_it;
2077 	if (sbi->secs_per_zone == 1)
2078 		goto got_it;
2079 	if (zoneno == old_zoneno)
2080 		goto got_it;
2081 	if (dir == ALLOC_LEFT) {
2082 		if (!go_left && zoneno + 1 >= total_zones)
2083 			goto got_it;
2084 		if (go_left && zoneno == 0)
2085 			goto got_it;
2086 	}
2087 	for (i = 0; i < NR_CURSEG_TYPE; i++)
2088 		if (CURSEG_I(sbi, i)->zone == zoneno)
2089 			break;
2090 
2091 	if (i < NR_CURSEG_TYPE) {
2092 		/* zone is in user, try another */
2093 		if (go_left)
2094 			hint = zoneno * sbi->secs_per_zone - 1;
2095 		else if (zoneno + 1 >= total_zones)
2096 			hint = 0;
2097 		else
2098 			hint = (zoneno + 1) * sbi->secs_per_zone;
2099 		init = false;
2100 		goto find_other_zone;
2101 	}
2102 got_it:
2103 	/* set it as dirty segment in free segmap */
2104 	f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
2105 	__set_inuse(sbi, segno);
2106 	*newseg = segno;
2107 	spin_unlock(&free_i->segmap_lock);
2108 }
2109 
2110 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
2111 {
2112 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2113 	struct summary_footer *sum_footer;
2114 
2115 	curseg->segno = curseg->next_segno;
2116 	curseg->zone = GET_ZONE_FROM_SEG(sbi, curseg->segno);
2117 	curseg->next_blkoff = 0;
2118 	curseg->next_segno = NULL_SEGNO;
2119 
2120 	sum_footer = &(curseg->sum_blk->footer);
2121 	memset(sum_footer, 0, sizeof(struct summary_footer));
2122 	if (IS_DATASEG(type))
2123 		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
2124 	if (IS_NODESEG(type))
2125 		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
2126 	__set_sit_entry_type(sbi, type, curseg->segno, modified);
2127 }
2128 
2129 static unsigned int __get_next_segno(struct f2fs_sb_info *sbi, int type)
2130 {
2131 	/* if segs_per_sec is large than 1, we need to keep original policy. */
2132 	if (sbi->segs_per_sec != 1)
2133 		return CURSEG_I(sbi, type)->segno;
2134 
2135 	if (test_opt(sbi, NOHEAP) &&
2136 		(type == CURSEG_HOT_DATA || IS_NODESEG(type)))
2137 		return 0;
2138 
2139 	if (SIT_I(sbi)->last_victim[ALLOC_NEXT])
2140 		return SIT_I(sbi)->last_victim[ALLOC_NEXT];
2141 
2142 	/* find segments from 0 to reuse freed segments */
2143 	if (F2FS_OPTION(sbi).alloc_mode == ALLOC_MODE_REUSE)
2144 		return 0;
2145 
2146 	return CURSEG_I(sbi, type)->segno;
2147 }
2148 
2149 /*
2150  * Allocate a current working segment.
2151  * This function always allocates a free segment in LFS manner.
2152  */
2153 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
2154 {
2155 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2156 	unsigned int segno = curseg->segno;
2157 	int dir = ALLOC_LEFT;
2158 
2159 	write_sum_page(sbi, curseg->sum_blk,
2160 				GET_SUM_BLOCK(sbi, segno));
2161 	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
2162 		dir = ALLOC_RIGHT;
2163 
2164 	if (test_opt(sbi, NOHEAP))
2165 		dir = ALLOC_RIGHT;
2166 
2167 	segno = __get_next_segno(sbi, type);
2168 	get_new_segment(sbi, &segno, new_sec, dir);
2169 	curseg->next_segno = segno;
2170 	reset_curseg(sbi, type, 1);
2171 	curseg->alloc_type = LFS;
2172 }
2173 
2174 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
2175 			struct curseg_info *seg, block_t start)
2176 {
2177 	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
2178 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
2179 	unsigned long *target_map = SIT_I(sbi)->tmp_map;
2180 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
2181 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
2182 	int i, pos;
2183 
2184 	for (i = 0; i < entries; i++)
2185 		target_map[i] = ckpt_map[i] | cur_map[i];
2186 
2187 	pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
2188 
2189 	seg->next_blkoff = pos;
2190 }
2191 
2192 /*
2193  * If a segment is written by LFS manner, next block offset is just obtained
2194  * by increasing the current block offset. However, if a segment is written by
2195  * SSR manner, next block offset obtained by calling __next_free_blkoff
2196  */
2197 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
2198 				struct curseg_info *seg)
2199 {
2200 	if (seg->alloc_type == SSR)
2201 		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
2202 	else
2203 		seg->next_blkoff++;
2204 }
2205 
2206 /*
2207  * This function always allocates a used segment(from dirty seglist) by SSR
2208  * manner, so it should recover the existing segment information of valid blocks
2209  */
2210 static void change_curseg(struct f2fs_sb_info *sbi, int type)
2211 {
2212 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2213 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2214 	unsigned int new_segno = curseg->next_segno;
2215 	struct f2fs_summary_block *sum_node;
2216 	struct page *sum_page;
2217 
2218 	write_sum_page(sbi, curseg->sum_blk,
2219 				GET_SUM_BLOCK(sbi, curseg->segno));
2220 	__set_test_and_inuse(sbi, new_segno);
2221 
2222 	mutex_lock(&dirty_i->seglist_lock);
2223 	__remove_dirty_segment(sbi, new_segno, PRE);
2224 	__remove_dirty_segment(sbi, new_segno, DIRTY);
2225 	mutex_unlock(&dirty_i->seglist_lock);
2226 
2227 	reset_curseg(sbi, type, 1);
2228 	curseg->alloc_type = SSR;
2229 	__next_free_blkoff(sbi, curseg, 0);
2230 
2231 	sum_page = get_sum_page(sbi, new_segno);
2232 	sum_node = (struct f2fs_summary_block *)page_address(sum_page);
2233 	memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
2234 	f2fs_put_page(sum_page, 1);
2235 }
2236 
2237 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
2238 {
2239 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2240 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
2241 	unsigned segno = NULL_SEGNO;
2242 	int i, cnt;
2243 	bool reversed = false;
2244 
2245 	/* need_SSR() already forces to do this */
2246 	if (v_ops->get_victim(sbi, &segno, BG_GC, type, SSR)) {
2247 		curseg->next_segno = segno;
2248 		return 1;
2249 	}
2250 
2251 	/* For node segments, let's do SSR more intensively */
2252 	if (IS_NODESEG(type)) {
2253 		if (type >= CURSEG_WARM_NODE) {
2254 			reversed = true;
2255 			i = CURSEG_COLD_NODE;
2256 		} else {
2257 			i = CURSEG_HOT_NODE;
2258 		}
2259 		cnt = NR_CURSEG_NODE_TYPE;
2260 	} else {
2261 		if (type >= CURSEG_WARM_DATA) {
2262 			reversed = true;
2263 			i = CURSEG_COLD_DATA;
2264 		} else {
2265 			i = CURSEG_HOT_DATA;
2266 		}
2267 		cnt = NR_CURSEG_DATA_TYPE;
2268 	}
2269 
2270 	for (; cnt-- > 0; reversed ? i-- : i++) {
2271 		if (i == type)
2272 			continue;
2273 		if (v_ops->get_victim(sbi, &segno, BG_GC, i, SSR)) {
2274 			curseg->next_segno = segno;
2275 			return 1;
2276 		}
2277 	}
2278 	return 0;
2279 }
2280 
2281 /*
2282  * flush out current segment and replace it with new segment
2283  * This function should be returned with success, otherwise BUG
2284  */
2285 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
2286 						int type, bool force)
2287 {
2288 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2289 
2290 	if (force)
2291 		new_curseg(sbi, type, true);
2292 	else if (!is_set_ckpt_flags(sbi, CP_CRC_RECOVERY_FLAG) &&
2293 					type == CURSEG_WARM_NODE)
2294 		new_curseg(sbi, type, false);
2295 	else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
2296 		new_curseg(sbi, type, false);
2297 	else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
2298 		change_curseg(sbi, type);
2299 	else
2300 		new_curseg(sbi, type, false);
2301 
2302 	stat_inc_seg_type(sbi, curseg);
2303 }
2304 
2305 void allocate_new_segments(struct f2fs_sb_info *sbi)
2306 {
2307 	struct curseg_info *curseg;
2308 	unsigned int old_segno;
2309 	int i;
2310 
2311 	down_write(&SIT_I(sbi)->sentry_lock);
2312 
2313 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
2314 		curseg = CURSEG_I(sbi, i);
2315 		old_segno = curseg->segno;
2316 		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
2317 		locate_dirty_segment(sbi, old_segno);
2318 	}
2319 
2320 	up_write(&SIT_I(sbi)->sentry_lock);
2321 }
2322 
2323 static const struct segment_allocation default_salloc_ops = {
2324 	.allocate_segment = allocate_segment_by_default,
2325 };
2326 
2327 bool exist_trim_candidates(struct f2fs_sb_info *sbi, struct cp_control *cpc)
2328 {
2329 	__u64 trim_start = cpc->trim_start;
2330 	bool has_candidate = false;
2331 
2332 	down_write(&SIT_I(sbi)->sentry_lock);
2333 	for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++) {
2334 		if (add_discard_addrs(sbi, cpc, true)) {
2335 			has_candidate = true;
2336 			break;
2337 		}
2338 	}
2339 	up_write(&SIT_I(sbi)->sentry_lock);
2340 
2341 	cpc->trim_start = trim_start;
2342 	return has_candidate;
2343 }
2344 
2345 static void __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
2346 					struct discard_policy *dpolicy,
2347 					unsigned int start, unsigned int end)
2348 {
2349 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
2350 	struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
2351 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
2352 	struct discard_cmd *dc;
2353 	struct blk_plug plug;
2354 	int issued;
2355 
2356 next:
2357 	issued = 0;
2358 
2359 	mutex_lock(&dcc->cmd_lock);
2360 	f2fs_bug_on(sbi, !__check_rb_tree_consistence(sbi, &dcc->root));
2361 
2362 	dc = (struct discard_cmd *)__lookup_rb_tree_ret(&dcc->root,
2363 					NULL, start,
2364 					(struct rb_entry **)&prev_dc,
2365 					(struct rb_entry **)&next_dc,
2366 					&insert_p, &insert_parent, true);
2367 	if (!dc)
2368 		dc = next_dc;
2369 
2370 	blk_start_plug(&plug);
2371 
2372 	while (dc && dc->lstart <= end) {
2373 		struct rb_node *node;
2374 
2375 		if (dc->len < dpolicy->granularity)
2376 			goto skip;
2377 
2378 		if (dc->state != D_PREP) {
2379 			list_move_tail(&dc->list, &dcc->fstrim_list);
2380 			goto skip;
2381 		}
2382 
2383 		__submit_discard_cmd(sbi, dpolicy, dc);
2384 
2385 		if (++issued >= dpolicy->max_requests) {
2386 			start = dc->lstart + dc->len;
2387 
2388 			blk_finish_plug(&plug);
2389 			mutex_unlock(&dcc->cmd_lock);
2390 			__wait_all_discard_cmd(sbi, NULL);
2391 			congestion_wait(BLK_RW_ASYNC, HZ/50);
2392 			goto next;
2393 		}
2394 skip:
2395 		node = rb_next(&dc->rb_node);
2396 		dc = rb_entry_safe(node, struct discard_cmd, rb_node);
2397 
2398 		if (fatal_signal_pending(current))
2399 			break;
2400 	}
2401 
2402 	blk_finish_plug(&plug);
2403 	mutex_unlock(&dcc->cmd_lock);
2404 }
2405 
2406 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
2407 {
2408 	__u64 start = F2FS_BYTES_TO_BLK(range->start);
2409 	__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
2410 	unsigned int start_segno, end_segno;
2411 	block_t start_block, end_block;
2412 	struct cp_control cpc;
2413 	struct discard_policy dpolicy;
2414 	unsigned long long trimmed = 0;
2415 	int err = 0;
2416 
2417 	if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
2418 		return -EINVAL;
2419 
2420 	if (end <= MAIN_BLKADDR(sbi))
2421 		return -EINVAL;
2422 
2423 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
2424 		f2fs_msg(sbi->sb, KERN_WARNING,
2425 			"Found FS corruption, run fsck to fix.");
2426 		return -EIO;
2427 	}
2428 
2429 	/* start/end segment number in main_area */
2430 	start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
2431 	end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
2432 						GET_SEGNO(sbi, end);
2433 
2434 	cpc.reason = CP_DISCARD;
2435 	cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
2436 	cpc.trim_start = start_segno;
2437 	cpc.trim_end = end_segno;
2438 
2439 	if (sbi->discard_blks == 0)
2440 		goto out;
2441 
2442 	mutex_lock(&sbi->gc_mutex);
2443 	err = write_checkpoint(sbi, &cpc);
2444 	mutex_unlock(&sbi->gc_mutex);
2445 	if (err)
2446 		goto out;
2447 
2448 	start_block = START_BLOCK(sbi, start_segno);
2449 	end_block = START_BLOCK(sbi, end_segno + 1);
2450 
2451 	__init_discard_policy(sbi, &dpolicy, DPOLICY_FSTRIM, cpc.trim_minlen);
2452 	__issue_discard_cmd_range(sbi, &dpolicy, start_block, end_block);
2453 
2454 	/*
2455 	 * We filed discard candidates, but actually we don't need to wait for
2456 	 * all of them, since they'll be issued in idle time along with runtime
2457 	 * discard option. User configuration looks like using runtime discard
2458 	 * or periodic fstrim instead of it.
2459 	 */
2460 	if (!test_opt(sbi, DISCARD)) {
2461 		trimmed = __wait_discard_cmd_range(sbi, &dpolicy,
2462 					start_block, end_block);
2463 		range->len = F2FS_BLK_TO_BYTES(trimmed);
2464 	}
2465 out:
2466 	return err;
2467 }
2468 
2469 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
2470 {
2471 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2472 	if (curseg->next_blkoff < sbi->blocks_per_seg)
2473 		return true;
2474 	return false;
2475 }
2476 
2477 int rw_hint_to_seg_type(enum rw_hint hint)
2478 {
2479 	switch (hint) {
2480 	case WRITE_LIFE_SHORT:
2481 		return CURSEG_HOT_DATA;
2482 	case WRITE_LIFE_EXTREME:
2483 		return CURSEG_COLD_DATA;
2484 	default:
2485 		return CURSEG_WARM_DATA;
2486 	}
2487 }
2488 
2489 /* This returns write hints for each segment type. This hints will be
2490  * passed down to block layer. There are mapping tables which depend on
2491  * the mount option 'whint_mode'.
2492  *
2493  * 1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
2494  *
2495  * 2) whint_mode=user-based. F2FS tries to pass down hints given by users.
2496  *
2497  * User                  F2FS                     Block
2498  * ----                  ----                     -----
2499  *                       META                     WRITE_LIFE_NOT_SET
2500  *                       HOT_NODE                 "
2501  *                       WARM_NODE                "
2502  *                       COLD_NODE                "
2503  * ioctl(COLD)           COLD_DATA                WRITE_LIFE_EXTREME
2504  * extension list        "                        "
2505  *
2506  * -- buffered io
2507  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2508  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2509  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2510  * WRITE_LIFE_NONE       "                        "
2511  * WRITE_LIFE_MEDIUM     "                        "
2512  * WRITE_LIFE_LONG       "                        "
2513  *
2514  * -- direct io
2515  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2516  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2517  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2518  * WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
2519  * WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
2520  * WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG
2521  *
2522  * 3) whint_mode=fs-based. F2FS passes down hints with its policy.
2523  *
2524  * User                  F2FS                     Block
2525  * ----                  ----                     -----
2526  *                       META                     WRITE_LIFE_MEDIUM;
2527  *                       HOT_NODE                 WRITE_LIFE_NOT_SET
2528  *                       WARM_NODE                "
2529  *                       COLD_NODE                WRITE_LIFE_NONE
2530  * ioctl(COLD)           COLD_DATA                WRITE_LIFE_EXTREME
2531  * extension list        "                        "
2532  *
2533  * -- buffered io
2534  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2535  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2536  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_LONG
2537  * WRITE_LIFE_NONE       "                        "
2538  * WRITE_LIFE_MEDIUM     "                        "
2539  * WRITE_LIFE_LONG       "                        "
2540  *
2541  * -- direct io
2542  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2543  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2544  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2545  * WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
2546  * WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
2547  * WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG
2548  */
2549 
2550 enum rw_hint io_type_to_rw_hint(struct f2fs_sb_info *sbi,
2551 				enum page_type type, enum temp_type temp)
2552 {
2553 	if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_USER) {
2554 		if (type == DATA) {
2555 			if (temp == WARM)
2556 				return WRITE_LIFE_NOT_SET;
2557 			else if (temp == HOT)
2558 				return WRITE_LIFE_SHORT;
2559 			else if (temp == COLD)
2560 				return WRITE_LIFE_EXTREME;
2561 		} else {
2562 			return WRITE_LIFE_NOT_SET;
2563 		}
2564 	} else if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_FS) {
2565 		if (type == DATA) {
2566 			if (temp == WARM)
2567 				return WRITE_LIFE_LONG;
2568 			else if (temp == HOT)
2569 				return WRITE_LIFE_SHORT;
2570 			else if (temp == COLD)
2571 				return WRITE_LIFE_EXTREME;
2572 		} else if (type == NODE) {
2573 			if (temp == WARM || temp == HOT)
2574 				return WRITE_LIFE_NOT_SET;
2575 			else if (temp == COLD)
2576 				return WRITE_LIFE_NONE;
2577 		} else if (type == META) {
2578 			return WRITE_LIFE_MEDIUM;
2579 		}
2580 	}
2581 	return WRITE_LIFE_NOT_SET;
2582 }
2583 
2584 static int __get_segment_type_2(struct f2fs_io_info *fio)
2585 {
2586 	if (fio->type == DATA)
2587 		return CURSEG_HOT_DATA;
2588 	else
2589 		return CURSEG_HOT_NODE;
2590 }
2591 
2592 static int __get_segment_type_4(struct f2fs_io_info *fio)
2593 {
2594 	if (fio->type == DATA) {
2595 		struct inode *inode = fio->page->mapping->host;
2596 
2597 		if (S_ISDIR(inode->i_mode))
2598 			return CURSEG_HOT_DATA;
2599 		else
2600 			return CURSEG_COLD_DATA;
2601 	} else {
2602 		if (IS_DNODE(fio->page) && is_cold_node(fio->page))
2603 			return CURSEG_WARM_NODE;
2604 		else
2605 			return CURSEG_COLD_NODE;
2606 	}
2607 }
2608 
2609 static int __get_segment_type_6(struct f2fs_io_info *fio)
2610 {
2611 	if (fio->type == DATA) {
2612 		struct inode *inode = fio->page->mapping->host;
2613 
2614 		if (is_cold_data(fio->page) || file_is_cold(inode))
2615 			return CURSEG_COLD_DATA;
2616 		if (file_is_hot(inode) ||
2617 				is_inode_flag_set(inode, FI_HOT_DATA) ||
2618 				is_inode_flag_set(inode, FI_ATOMIC_FILE) ||
2619 				is_inode_flag_set(inode, FI_VOLATILE_FILE))
2620 			return CURSEG_HOT_DATA;
2621 		return rw_hint_to_seg_type(inode->i_write_hint);
2622 	} else {
2623 		if (IS_DNODE(fio->page))
2624 			return is_cold_node(fio->page) ? CURSEG_WARM_NODE :
2625 						CURSEG_HOT_NODE;
2626 		return CURSEG_COLD_NODE;
2627 	}
2628 }
2629 
2630 static int __get_segment_type(struct f2fs_io_info *fio)
2631 {
2632 	int type = 0;
2633 
2634 	switch (F2FS_OPTION(fio->sbi).active_logs) {
2635 	case 2:
2636 		type = __get_segment_type_2(fio);
2637 		break;
2638 	case 4:
2639 		type = __get_segment_type_4(fio);
2640 		break;
2641 	case 6:
2642 		type = __get_segment_type_6(fio);
2643 		break;
2644 	default:
2645 		f2fs_bug_on(fio->sbi, true);
2646 	}
2647 
2648 	if (IS_HOT(type))
2649 		fio->temp = HOT;
2650 	else if (IS_WARM(type))
2651 		fio->temp = WARM;
2652 	else
2653 		fio->temp = COLD;
2654 	return type;
2655 }
2656 
2657 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
2658 		block_t old_blkaddr, block_t *new_blkaddr,
2659 		struct f2fs_summary *sum, int type,
2660 		struct f2fs_io_info *fio, bool add_list)
2661 {
2662 	struct sit_info *sit_i = SIT_I(sbi);
2663 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2664 
2665 	down_read(&SM_I(sbi)->curseg_lock);
2666 
2667 	mutex_lock(&curseg->curseg_mutex);
2668 	down_write(&sit_i->sentry_lock);
2669 
2670 	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
2671 
2672 	f2fs_wait_discard_bio(sbi, *new_blkaddr);
2673 
2674 	/*
2675 	 * __add_sum_entry should be resided under the curseg_mutex
2676 	 * because, this function updates a summary entry in the
2677 	 * current summary block.
2678 	 */
2679 	__add_sum_entry(sbi, type, sum);
2680 
2681 	__refresh_next_blkoff(sbi, curseg);
2682 
2683 	stat_inc_block_count(sbi, curseg);
2684 
2685 	/*
2686 	 * SIT information should be updated before segment allocation,
2687 	 * since SSR needs latest valid block information.
2688 	 */
2689 	update_sit_entry(sbi, *new_blkaddr, 1);
2690 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
2691 		update_sit_entry(sbi, old_blkaddr, -1);
2692 
2693 	if (!__has_curseg_space(sbi, type))
2694 		sit_i->s_ops->allocate_segment(sbi, type, false);
2695 
2696 	/*
2697 	 * segment dirty status should be updated after segment allocation,
2698 	 * so we just need to update status only one time after previous
2699 	 * segment being closed.
2700 	 */
2701 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
2702 	locate_dirty_segment(sbi, GET_SEGNO(sbi, *new_blkaddr));
2703 
2704 	up_write(&sit_i->sentry_lock);
2705 
2706 	if (page && IS_NODESEG(type)) {
2707 		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
2708 
2709 		f2fs_inode_chksum_set(sbi, page);
2710 	}
2711 
2712 	if (add_list) {
2713 		struct f2fs_bio_info *io;
2714 
2715 		INIT_LIST_HEAD(&fio->list);
2716 		fio->in_list = true;
2717 		io = sbi->write_io[fio->type] + fio->temp;
2718 		spin_lock(&io->io_lock);
2719 		list_add_tail(&fio->list, &io->io_list);
2720 		spin_unlock(&io->io_lock);
2721 	}
2722 
2723 	mutex_unlock(&curseg->curseg_mutex);
2724 
2725 	up_read(&SM_I(sbi)->curseg_lock);
2726 }
2727 
2728 static void update_device_state(struct f2fs_io_info *fio)
2729 {
2730 	struct f2fs_sb_info *sbi = fio->sbi;
2731 	unsigned int devidx;
2732 
2733 	if (!sbi->s_ndevs)
2734 		return;
2735 
2736 	devidx = f2fs_target_device_index(sbi, fio->new_blkaddr);
2737 
2738 	/* update device state for fsync */
2739 	set_dirty_device(sbi, fio->ino, devidx, FLUSH_INO);
2740 
2741 	/* update device state for checkpoint */
2742 	if (!f2fs_test_bit(devidx, (char *)&sbi->dirty_device)) {
2743 		spin_lock(&sbi->dev_lock);
2744 		f2fs_set_bit(devidx, (char *)&sbi->dirty_device);
2745 		spin_unlock(&sbi->dev_lock);
2746 	}
2747 }
2748 
2749 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
2750 {
2751 	int type = __get_segment_type(fio);
2752 	int err;
2753 	bool keep_order = (test_opt(fio->sbi, LFS) && type == CURSEG_COLD_DATA);
2754 
2755 	if (keep_order)
2756 		down_read(&fio->sbi->io_order_lock);
2757 reallocate:
2758 	allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
2759 			&fio->new_blkaddr, sum, type, fio, true);
2760 
2761 	/* writeout dirty page into bdev */
2762 	err = f2fs_submit_page_write(fio);
2763 	if (err == -EAGAIN) {
2764 		fio->old_blkaddr = fio->new_blkaddr;
2765 		goto reallocate;
2766 	} else if (!err) {
2767 		update_device_state(fio);
2768 	}
2769 	if (keep_order)
2770 		up_read(&fio->sbi->io_order_lock);
2771 }
2772 
2773 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page,
2774 					enum iostat_type io_type)
2775 {
2776 	struct f2fs_io_info fio = {
2777 		.sbi = sbi,
2778 		.type = META,
2779 		.temp = HOT,
2780 		.op = REQ_OP_WRITE,
2781 		.op_flags = REQ_SYNC | REQ_META | REQ_PRIO,
2782 		.old_blkaddr = page->index,
2783 		.new_blkaddr = page->index,
2784 		.page = page,
2785 		.encrypted_page = NULL,
2786 		.in_list = false,
2787 	};
2788 
2789 	if (unlikely(page->index >= MAIN_BLKADDR(sbi)))
2790 		fio.op_flags &= ~REQ_META;
2791 
2792 	set_page_writeback(page);
2793 	ClearPageError(page);
2794 	f2fs_submit_page_write(&fio);
2795 
2796 	f2fs_update_iostat(sbi, io_type, F2FS_BLKSIZE);
2797 }
2798 
2799 void write_node_page(unsigned int nid, struct f2fs_io_info *fio)
2800 {
2801 	struct f2fs_summary sum;
2802 
2803 	set_summary(&sum, nid, 0, 0);
2804 	do_write_page(&sum, fio);
2805 
2806 	f2fs_update_iostat(fio->sbi, fio->io_type, F2FS_BLKSIZE);
2807 }
2808 
2809 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio)
2810 {
2811 	struct f2fs_sb_info *sbi = fio->sbi;
2812 	struct f2fs_summary sum;
2813 	struct node_info ni;
2814 
2815 	f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
2816 	get_node_info(sbi, dn->nid, &ni);
2817 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
2818 	do_write_page(&sum, fio);
2819 	f2fs_update_data_blkaddr(dn, fio->new_blkaddr);
2820 
2821 	f2fs_update_iostat(sbi, fio->io_type, F2FS_BLKSIZE);
2822 }
2823 
2824 int rewrite_data_page(struct f2fs_io_info *fio)
2825 {
2826 	int err;
2827 	struct f2fs_sb_info *sbi = fio->sbi;
2828 
2829 	fio->new_blkaddr = fio->old_blkaddr;
2830 	/* i/o temperature is needed for passing down write hints */
2831 	__get_segment_type(fio);
2832 
2833 	f2fs_bug_on(sbi, !IS_DATASEG(get_seg_entry(sbi,
2834 			GET_SEGNO(sbi, fio->new_blkaddr))->type));
2835 
2836 	stat_inc_inplace_blocks(fio->sbi);
2837 
2838 	err = f2fs_submit_page_bio(fio);
2839 	if (!err)
2840 		update_device_state(fio);
2841 
2842 	f2fs_update_iostat(fio->sbi, fio->io_type, F2FS_BLKSIZE);
2843 
2844 	return err;
2845 }
2846 
2847 static inline int __f2fs_get_curseg(struct f2fs_sb_info *sbi,
2848 						unsigned int segno)
2849 {
2850 	int i;
2851 
2852 	for (i = CURSEG_HOT_DATA; i < NO_CHECK_TYPE; i++) {
2853 		if (CURSEG_I(sbi, i)->segno == segno)
2854 			break;
2855 	}
2856 	return i;
2857 }
2858 
2859 void __f2fs_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
2860 				block_t old_blkaddr, block_t new_blkaddr,
2861 				bool recover_curseg, bool recover_newaddr)
2862 {
2863 	struct sit_info *sit_i = SIT_I(sbi);
2864 	struct curseg_info *curseg;
2865 	unsigned int segno, old_cursegno;
2866 	struct seg_entry *se;
2867 	int type;
2868 	unsigned short old_blkoff;
2869 
2870 	segno = GET_SEGNO(sbi, new_blkaddr);
2871 	se = get_seg_entry(sbi, segno);
2872 	type = se->type;
2873 
2874 	down_write(&SM_I(sbi)->curseg_lock);
2875 
2876 	if (!recover_curseg) {
2877 		/* for recovery flow */
2878 		if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
2879 			if (old_blkaddr == NULL_ADDR)
2880 				type = CURSEG_COLD_DATA;
2881 			else
2882 				type = CURSEG_WARM_DATA;
2883 		}
2884 	} else {
2885 		if (IS_CURSEG(sbi, segno)) {
2886 			/* se->type is volatile as SSR allocation */
2887 			type = __f2fs_get_curseg(sbi, segno);
2888 			f2fs_bug_on(sbi, type == NO_CHECK_TYPE);
2889 		} else {
2890 			type = CURSEG_WARM_DATA;
2891 		}
2892 	}
2893 
2894 	f2fs_bug_on(sbi, !IS_DATASEG(type));
2895 	curseg = CURSEG_I(sbi, type);
2896 
2897 	mutex_lock(&curseg->curseg_mutex);
2898 	down_write(&sit_i->sentry_lock);
2899 
2900 	old_cursegno = curseg->segno;
2901 	old_blkoff = curseg->next_blkoff;
2902 
2903 	/* change the current segment */
2904 	if (segno != curseg->segno) {
2905 		curseg->next_segno = segno;
2906 		change_curseg(sbi, type);
2907 	}
2908 
2909 	curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
2910 	__add_sum_entry(sbi, type, sum);
2911 
2912 	if (!recover_curseg || recover_newaddr)
2913 		update_sit_entry(sbi, new_blkaddr, 1);
2914 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
2915 		update_sit_entry(sbi, old_blkaddr, -1);
2916 
2917 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
2918 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new_blkaddr));
2919 
2920 	locate_dirty_segment(sbi, old_cursegno);
2921 
2922 	if (recover_curseg) {
2923 		if (old_cursegno != curseg->segno) {
2924 			curseg->next_segno = old_cursegno;
2925 			change_curseg(sbi, type);
2926 		}
2927 		curseg->next_blkoff = old_blkoff;
2928 	}
2929 
2930 	up_write(&sit_i->sentry_lock);
2931 	mutex_unlock(&curseg->curseg_mutex);
2932 	up_write(&SM_I(sbi)->curseg_lock);
2933 }
2934 
2935 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
2936 				block_t old_addr, block_t new_addr,
2937 				unsigned char version, bool recover_curseg,
2938 				bool recover_newaddr)
2939 {
2940 	struct f2fs_summary sum;
2941 
2942 	set_summary(&sum, dn->nid, dn->ofs_in_node, version);
2943 
2944 	__f2fs_replace_block(sbi, &sum, old_addr, new_addr,
2945 					recover_curseg, recover_newaddr);
2946 
2947 	f2fs_update_data_blkaddr(dn, new_addr);
2948 }
2949 
2950 void f2fs_wait_on_page_writeback(struct page *page,
2951 				enum page_type type, bool ordered)
2952 {
2953 	if (PageWriteback(page)) {
2954 		struct f2fs_sb_info *sbi = F2FS_P_SB(page);
2955 
2956 		f2fs_submit_merged_write_cond(sbi, page->mapping->host,
2957 						0, page->index, type);
2958 		if (ordered)
2959 			wait_on_page_writeback(page);
2960 		else
2961 			wait_for_stable_page(page);
2962 	}
2963 }
2964 
2965 void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr)
2966 {
2967 	struct page *cpage;
2968 
2969 	if (!is_valid_blkaddr(blkaddr))
2970 		return;
2971 
2972 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
2973 	if (cpage) {
2974 		f2fs_wait_on_page_writeback(cpage, DATA, true);
2975 		f2fs_put_page(cpage, 1);
2976 	}
2977 }
2978 
2979 static void read_compacted_summaries(struct f2fs_sb_info *sbi)
2980 {
2981 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2982 	struct curseg_info *seg_i;
2983 	unsigned char *kaddr;
2984 	struct page *page;
2985 	block_t start;
2986 	int i, j, offset;
2987 
2988 	start = start_sum_block(sbi);
2989 
2990 	page = get_meta_page(sbi, start++);
2991 	kaddr = (unsigned char *)page_address(page);
2992 
2993 	/* Step 1: restore nat cache */
2994 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
2995 	memcpy(seg_i->journal, kaddr, SUM_JOURNAL_SIZE);
2996 
2997 	/* Step 2: restore sit cache */
2998 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
2999 	memcpy(seg_i->journal, kaddr + SUM_JOURNAL_SIZE, SUM_JOURNAL_SIZE);
3000 	offset = 2 * SUM_JOURNAL_SIZE;
3001 
3002 	/* Step 3: restore summary entries */
3003 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
3004 		unsigned short blk_off;
3005 		unsigned int segno;
3006 
3007 		seg_i = CURSEG_I(sbi, i);
3008 		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
3009 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
3010 		seg_i->next_segno = segno;
3011 		reset_curseg(sbi, i, 0);
3012 		seg_i->alloc_type = ckpt->alloc_type[i];
3013 		seg_i->next_blkoff = blk_off;
3014 
3015 		if (seg_i->alloc_type == SSR)
3016 			blk_off = sbi->blocks_per_seg;
3017 
3018 		for (j = 0; j < blk_off; j++) {
3019 			struct f2fs_summary *s;
3020 			s = (struct f2fs_summary *)(kaddr + offset);
3021 			seg_i->sum_blk->entries[j] = *s;
3022 			offset += SUMMARY_SIZE;
3023 			if (offset + SUMMARY_SIZE <= PAGE_SIZE -
3024 						SUM_FOOTER_SIZE)
3025 				continue;
3026 
3027 			f2fs_put_page(page, 1);
3028 			page = NULL;
3029 
3030 			page = get_meta_page(sbi, start++);
3031 			kaddr = (unsigned char *)page_address(page);
3032 			offset = 0;
3033 		}
3034 	}
3035 	f2fs_put_page(page, 1);
3036 }
3037 
3038 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
3039 {
3040 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3041 	struct f2fs_summary_block *sum;
3042 	struct curseg_info *curseg;
3043 	struct page *new;
3044 	unsigned short blk_off;
3045 	unsigned int segno = 0;
3046 	block_t blk_addr = 0;
3047 
3048 	/* get segment number and block addr */
3049 	if (IS_DATASEG(type)) {
3050 		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
3051 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
3052 							CURSEG_HOT_DATA]);
3053 		if (__exist_node_summaries(sbi))
3054 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
3055 		else
3056 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
3057 	} else {
3058 		segno = le32_to_cpu(ckpt->cur_node_segno[type -
3059 							CURSEG_HOT_NODE]);
3060 		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
3061 							CURSEG_HOT_NODE]);
3062 		if (__exist_node_summaries(sbi))
3063 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
3064 							type - CURSEG_HOT_NODE);
3065 		else
3066 			blk_addr = GET_SUM_BLOCK(sbi, segno);
3067 	}
3068 
3069 	new = get_meta_page(sbi, blk_addr);
3070 	sum = (struct f2fs_summary_block *)page_address(new);
3071 
3072 	if (IS_NODESEG(type)) {
3073 		if (__exist_node_summaries(sbi)) {
3074 			struct f2fs_summary *ns = &sum->entries[0];
3075 			int i;
3076 			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
3077 				ns->version = 0;
3078 				ns->ofs_in_node = 0;
3079 			}
3080 		} else {
3081 			restore_node_summary(sbi, segno, sum);
3082 		}
3083 	}
3084 
3085 	/* set uncompleted segment to curseg */
3086 	curseg = CURSEG_I(sbi, type);
3087 	mutex_lock(&curseg->curseg_mutex);
3088 
3089 	/* update journal info */
3090 	down_write(&curseg->journal_rwsem);
3091 	memcpy(curseg->journal, &sum->journal, SUM_JOURNAL_SIZE);
3092 	up_write(&curseg->journal_rwsem);
3093 
3094 	memcpy(curseg->sum_blk->entries, sum->entries, SUM_ENTRY_SIZE);
3095 	memcpy(&curseg->sum_blk->footer, &sum->footer, SUM_FOOTER_SIZE);
3096 	curseg->next_segno = segno;
3097 	reset_curseg(sbi, type, 0);
3098 	curseg->alloc_type = ckpt->alloc_type[type];
3099 	curseg->next_blkoff = blk_off;
3100 	mutex_unlock(&curseg->curseg_mutex);
3101 	f2fs_put_page(new, 1);
3102 	return 0;
3103 }
3104 
3105 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
3106 {
3107 	struct f2fs_journal *sit_j = CURSEG_I(sbi, CURSEG_COLD_DATA)->journal;
3108 	struct f2fs_journal *nat_j = CURSEG_I(sbi, CURSEG_HOT_DATA)->journal;
3109 	int type = CURSEG_HOT_DATA;
3110 	int err;
3111 
3112 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG)) {
3113 		int npages = npages_for_summary_flush(sbi, true);
3114 
3115 		if (npages >= 2)
3116 			ra_meta_pages(sbi, start_sum_block(sbi), npages,
3117 							META_CP, true);
3118 
3119 		/* restore for compacted data summary */
3120 		read_compacted_summaries(sbi);
3121 		type = CURSEG_HOT_NODE;
3122 	}
3123 
3124 	if (__exist_node_summaries(sbi))
3125 		ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
3126 					NR_CURSEG_TYPE - type, META_CP, true);
3127 
3128 	for (; type <= CURSEG_COLD_NODE; type++) {
3129 		err = read_normal_summaries(sbi, type);
3130 		if (err)
3131 			return err;
3132 	}
3133 
3134 	/* sanity check for summary blocks */
3135 	if (nats_in_cursum(nat_j) > NAT_JOURNAL_ENTRIES ||
3136 			sits_in_cursum(sit_j) > SIT_JOURNAL_ENTRIES)
3137 		return -EINVAL;
3138 
3139 	return 0;
3140 }
3141 
3142 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
3143 {
3144 	struct page *page;
3145 	unsigned char *kaddr;
3146 	struct f2fs_summary *summary;
3147 	struct curseg_info *seg_i;
3148 	int written_size = 0;
3149 	int i, j;
3150 
3151 	page = grab_meta_page(sbi, blkaddr++);
3152 	kaddr = (unsigned char *)page_address(page);
3153 	memset(kaddr, 0, PAGE_SIZE);
3154 
3155 	/* Step 1: write nat cache */
3156 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
3157 	memcpy(kaddr, seg_i->journal, SUM_JOURNAL_SIZE);
3158 	written_size += SUM_JOURNAL_SIZE;
3159 
3160 	/* Step 2: write sit cache */
3161 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
3162 	memcpy(kaddr + written_size, seg_i->journal, SUM_JOURNAL_SIZE);
3163 	written_size += SUM_JOURNAL_SIZE;
3164 
3165 	/* Step 3: write summary entries */
3166 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
3167 		unsigned short blkoff;
3168 		seg_i = CURSEG_I(sbi, i);
3169 		if (sbi->ckpt->alloc_type[i] == SSR)
3170 			blkoff = sbi->blocks_per_seg;
3171 		else
3172 			blkoff = curseg_blkoff(sbi, i);
3173 
3174 		for (j = 0; j < blkoff; j++) {
3175 			if (!page) {
3176 				page = grab_meta_page(sbi, blkaddr++);
3177 				kaddr = (unsigned char *)page_address(page);
3178 				memset(kaddr, 0, PAGE_SIZE);
3179 				written_size = 0;
3180 			}
3181 			summary = (struct f2fs_summary *)(kaddr + written_size);
3182 			*summary = seg_i->sum_blk->entries[j];
3183 			written_size += SUMMARY_SIZE;
3184 
3185 			if (written_size + SUMMARY_SIZE <= PAGE_SIZE -
3186 							SUM_FOOTER_SIZE)
3187 				continue;
3188 
3189 			set_page_dirty(page);
3190 			f2fs_put_page(page, 1);
3191 			page = NULL;
3192 		}
3193 	}
3194 	if (page) {
3195 		set_page_dirty(page);
3196 		f2fs_put_page(page, 1);
3197 	}
3198 }
3199 
3200 static void write_normal_summaries(struct f2fs_sb_info *sbi,
3201 					block_t blkaddr, int type)
3202 {
3203 	int i, end;
3204 	if (IS_DATASEG(type))
3205 		end = type + NR_CURSEG_DATA_TYPE;
3206 	else
3207 		end = type + NR_CURSEG_NODE_TYPE;
3208 
3209 	for (i = type; i < end; i++)
3210 		write_current_sum_page(sbi, i, blkaddr + (i - type));
3211 }
3212 
3213 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
3214 {
3215 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG))
3216 		write_compacted_summaries(sbi, start_blk);
3217 	else
3218 		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
3219 }
3220 
3221 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
3222 {
3223 	write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
3224 }
3225 
3226 int lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
3227 					unsigned int val, int alloc)
3228 {
3229 	int i;
3230 
3231 	if (type == NAT_JOURNAL) {
3232 		for (i = 0; i < nats_in_cursum(journal); i++) {
3233 			if (le32_to_cpu(nid_in_journal(journal, i)) == val)
3234 				return i;
3235 		}
3236 		if (alloc && __has_cursum_space(journal, 1, NAT_JOURNAL))
3237 			return update_nats_in_cursum(journal, 1);
3238 	} else if (type == SIT_JOURNAL) {
3239 		for (i = 0; i < sits_in_cursum(journal); i++)
3240 			if (le32_to_cpu(segno_in_journal(journal, i)) == val)
3241 				return i;
3242 		if (alloc && __has_cursum_space(journal, 1, SIT_JOURNAL))
3243 			return update_sits_in_cursum(journal, 1);
3244 	}
3245 	return -1;
3246 }
3247 
3248 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
3249 					unsigned int segno)
3250 {
3251 	return get_meta_page(sbi, current_sit_addr(sbi, segno));
3252 }
3253 
3254 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
3255 					unsigned int start)
3256 {
3257 	struct sit_info *sit_i = SIT_I(sbi);
3258 	struct page *page;
3259 	pgoff_t src_off, dst_off;
3260 
3261 	src_off = current_sit_addr(sbi, start);
3262 	dst_off = next_sit_addr(sbi, src_off);
3263 
3264 	page = grab_meta_page(sbi, dst_off);
3265 	seg_info_to_sit_page(sbi, page, start);
3266 
3267 	set_page_dirty(page);
3268 	set_to_next_sit(sit_i, start);
3269 
3270 	return page;
3271 }
3272 
3273 static struct sit_entry_set *grab_sit_entry_set(void)
3274 {
3275 	struct sit_entry_set *ses =
3276 			f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
3277 
3278 	ses->entry_cnt = 0;
3279 	INIT_LIST_HEAD(&ses->set_list);
3280 	return ses;
3281 }
3282 
3283 static void release_sit_entry_set(struct sit_entry_set *ses)
3284 {
3285 	list_del(&ses->set_list);
3286 	kmem_cache_free(sit_entry_set_slab, ses);
3287 }
3288 
3289 static void adjust_sit_entry_set(struct sit_entry_set *ses,
3290 						struct list_head *head)
3291 {
3292 	struct sit_entry_set *next = ses;
3293 
3294 	if (list_is_last(&ses->set_list, head))
3295 		return;
3296 
3297 	list_for_each_entry_continue(next, head, set_list)
3298 		if (ses->entry_cnt <= next->entry_cnt)
3299 			break;
3300 
3301 	list_move_tail(&ses->set_list, &next->set_list);
3302 }
3303 
3304 static void add_sit_entry(unsigned int segno, struct list_head *head)
3305 {
3306 	struct sit_entry_set *ses;
3307 	unsigned int start_segno = START_SEGNO(segno);
3308 
3309 	list_for_each_entry(ses, head, set_list) {
3310 		if (ses->start_segno == start_segno) {
3311 			ses->entry_cnt++;
3312 			adjust_sit_entry_set(ses, head);
3313 			return;
3314 		}
3315 	}
3316 
3317 	ses = grab_sit_entry_set();
3318 
3319 	ses->start_segno = start_segno;
3320 	ses->entry_cnt++;
3321 	list_add(&ses->set_list, head);
3322 }
3323 
3324 static void add_sits_in_set(struct f2fs_sb_info *sbi)
3325 {
3326 	struct f2fs_sm_info *sm_info = SM_I(sbi);
3327 	struct list_head *set_list = &sm_info->sit_entry_set;
3328 	unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
3329 	unsigned int segno;
3330 
3331 	for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
3332 		add_sit_entry(segno, set_list);
3333 }
3334 
3335 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
3336 {
3337 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3338 	struct f2fs_journal *journal = curseg->journal;
3339 	int i;
3340 
3341 	down_write(&curseg->journal_rwsem);
3342 	for (i = 0; i < sits_in_cursum(journal); i++) {
3343 		unsigned int segno;
3344 		bool dirtied;
3345 
3346 		segno = le32_to_cpu(segno_in_journal(journal, i));
3347 		dirtied = __mark_sit_entry_dirty(sbi, segno);
3348 
3349 		if (!dirtied)
3350 			add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
3351 	}
3352 	update_sits_in_cursum(journal, -i);
3353 	up_write(&curseg->journal_rwsem);
3354 }
3355 
3356 /*
3357  * CP calls this function, which flushes SIT entries including sit_journal,
3358  * and moves prefree segs to free segs.
3359  */
3360 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
3361 {
3362 	struct sit_info *sit_i = SIT_I(sbi);
3363 	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
3364 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3365 	struct f2fs_journal *journal = curseg->journal;
3366 	struct sit_entry_set *ses, *tmp;
3367 	struct list_head *head = &SM_I(sbi)->sit_entry_set;
3368 	bool to_journal = true;
3369 	struct seg_entry *se;
3370 
3371 	down_write(&sit_i->sentry_lock);
3372 
3373 	if (!sit_i->dirty_sentries)
3374 		goto out;
3375 
3376 	/*
3377 	 * add and account sit entries of dirty bitmap in sit entry
3378 	 * set temporarily
3379 	 */
3380 	add_sits_in_set(sbi);
3381 
3382 	/*
3383 	 * if there are no enough space in journal to store dirty sit
3384 	 * entries, remove all entries from journal and add and account
3385 	 * them in sit entry set.
3386 	 */
3387 	if (!__has_cursum_space(journal, sit_i->dirty_sentries, SIT_JOURNAL))
3388 		remove_sits_in_journal(sbi);
3389 
3390 	/*
3391 	 * there are two steps to flush sit entries:
3392 	 * #1, flush sit entries to journal in current cold data summary block.
3393 	 * #2, flush sit entries to sit page.
3394 	 */
3395 	list_for_each_entry_safe(ses, tmp, head, set_list) {
3396 		struct page *page = NULL;
3397 		struct f2fs_sit_block *raw_sit = NULL;
3398 		unsigned int start_segno = ses->start_segno;
3399 		unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
3400 						(unsigned long)MAIN_SEGS(sbi));
3401 		unsigned int segno = start_segno;
3402 
3403 		if (to_journal &&
3404 			!__has_cursum_space(journal, ses->entry_cnt, SIT_JOURNAL))
3405 			to_journal = false;
3406 
3407 		if (to_journal) {
3408 			down_write(&curseg->journal_rwsem);
3409 		} else {
3410 			page = get_next_sit_page(sbi, start_segno);
3411 			raw_sit = page_address(page);
3412 		}
3413 
3414 		/* flush dirty sit entries in region of current sit set */
3415 		for_each_set_bit_from(segno, bitmap, end) {
3416 			int offset, sit_offset;
3417 
3418 			se = get_seg_entry(sbi, segno);
3419 #ifdef CONFIG_F2FS_CHECK_FS
3420 			if (memcmp(se->cur_valid_map, se->cur_valid_map_mir,
3421 						SIT_VBLOCK_MAP_SIZE))
3422 				f2fs_bug_on(sbi, 1);
3423 #endif
3424 
3425 			/* add discard candidates */
3426 			if (!(cpc->reason & CP_DISCARD)) {
3427 				cpc->trim_start = segno;
3428 				add_discard_addrs(sbi, cpc, false);
3429 			}
3430 
3431 			if (to_journal) {
3432 				offset = lookup_journal_in_cursum(journal,
3433 							SIT_JOURNAL, segno, 1);
3434 				f2fs_bug_on(sbi, offset < 0);
3435 				segno_in_journal(journal, offset) =
3436 							cpu_to_le32(segno);
3437 				seg_info_to_raw_sit(se,
3438 					&sit_in_journal(journal, offset));
3439 				check_block_count(sbi, segno,
3440 					&sit_in_journal(journal, offset));
3441 			} else {
3442 				sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
3443 				seg_info_to_raw_sit(se,
3444 						&raw_sit->entries[sit_offset]);
3445 				check_block_count(sbi, segno,
3446 						&raw_sit->entries[sit_offset]);
3447 			}
3448 
3449 			__clear_bit(segno, bitmap);
3450 			sit_i->dirty_sentries--;
3451 			ses->entry_cnt--;
3452 		}
3453 
3454 		if (to_journal)
3455 			up_write(&curseg->journal_rwsem);
3456 		else
3457 			f2fs_put_page(page, 1);
3458 
3459 		f2fs_bug_on(sbi, ses->entry_cnt);
3460 		release_sit_entry_set(ses);
3461 	}
3462 
3463 	f2fs_bug_on(sbi, !list_empty(head));
3464 	f2fs_bug_on(sbi, sit_i->dirty_sentries);
3465 out:
3466 	if (cpc->reason & CP_DISCARD) {
3467 		__u64 trim_start = cpc->trim_start;
3468 
3469 		for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
3470 			add_discard_addrs(sbi, cpc, false);
3471 
3472 		cpc->trim_start = trim_start;
3473 	}
3474 	up_write(&sit_i->sentry_lock);
3475 
3476 	set_prefree_as_free_segments(sbi);
3477 }
3478 
3479 static int build_sit_info(struct f2fs_sb_info *sbi)
3480 {
3481 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
3482 	struct sit_info *sit_i;
3483 	unsigned int sit_segs, start;
3484 	char *src_bitmap;
3485 	unsigned int bitmap_size;
3486 
3487 	/* allocate memory for SIT information */
3488 	sit_i = f2fs_kzalloc(sbi, sizeof(struct sit_info), GFP_KERNEL);
3489 	if (!sit_i)
3490 		return -ENOMEM;
3491 
3492 	SM_I(sbi)->sit_info = sit_i;
3493 
3494 	sit_i->sentries = f2fs_kvzalloc(sbi, MAIN_SEGS(sbi) *
3495 					sizeof(struct seg_entry), GFP_KERNEL);
3496 	if (!sit_i->sentries)
3497 		return -ENOMEM;
3498 
3499 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3500 	sit_i->dirty_sentries_bitmap = f2fs_kvzalloc(sbi, bitmap_size,
3501 								GFP_KERNEL);
3502 	if (!sit_i->dirty_sentries_bitmap)
3503 		return -ENOMEM;
3504 
3505 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
3506 		sit_i->sentries[start].cur_valid_map
3507 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3508 		sit_i->sentries[start].ckpt_valid_map
3509 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3510 		if (!sit_i->sentries[start].cur_valid_map ||
3511 				!sit_i->sentries[start].ckpt_valid_map)
3512 			return -ENOMEM;
3513 
3514 #ifdef CONFIG_F2FS_CHECK_FS
3515 		sit_i->sentries[start].cur_valid_map_mir
3516 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3517 		if (!sit_i->sentries[start].cur_valid_map_mir)
3518 			return -ENOMEM;
3519 #endif
3520 
3521 		if (f2fs_discard_en(sbi)) {
3522 			sit_i->sentries[start].discard_map
3523 				= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE,
3524 								GFP_KERNEL);
3525 			if (!sit_i->sentries[start].discard_map)
3526 				return -ENOMEM;
3527 		}
3528 	}
3529 
3530 	sit_i->tmp_map = f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3531 	if (!sit_i->tmp_map)
3532 		return -ENOMEM;
3533 
3534 	if (sbi->segs_per_sec > 1) {
3535 		sit_i->sec_entries = f2fs_kvzalloc(sbi, MAIN_SECS(sbi) *
3536 					sizeof(struct sec_entry), GFP_KERNEL);
3537 		if (!sit_i->sec_entries)
3538 			return -ENOMEM;
3539 	}
3540 
3541 	/* get information related with SIT */
3542 	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
3543 
3544 	/* setup SIT bitmap from ckeckpoint pack */
3545 	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
3546 	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
3547 
3548 	sit_i->sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
3549 	if (!sit_i->sit_bitmap)
3550 		return -ENOMEM;
3551 
3552 #ifdef CONFIG_F2FS_CHECK_FS
3553 	sit_i->sit_bitmap_mir = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
3554 	if (!sit_i->sit_bitmap_mir)
3555 		return -ENOMEM;
3556 #endif
3557 
3558 	/* init SIT information */
3559 	sit_i->s_ops = &default_salloc_ops;
3560 
3561 	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
3562 	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
3563 	sit_i->written_valid_blocks = 0;
3564 	sit_i->bitmap_size = bitmap_size;
3565 	sit_i->dirty_sentries = 0;
3566 	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
3567 	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
3568 	sit_i->mounted_time = ktime_get_real_seconds();
3569 	init_rwsem(&sit_i->sentry_lock);
3570 	return 0;
3571 }
3572 
3573 static int build_free_segmap(struct f2fs_sb_info *sbi)
3574 {
3575 	struct free_segmap_info *free_i;
3576 	unsigned int bitmap_size, sec_bitmap_size;
3577 
3578 	/* allocate memory for free segmap information */
3579 	free_i = f2fs_kzalloc(sbi, sizeof(struct free_segmap_info), GFP_KERNEL);
3580 	if (!free_i)
3581 		return -ENOMEM;
3582 
3583 	SM_I(sbi)->free_info = free_i;
3584 
3585 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3586 	free_i->free_segmap = f2fs_kvmalloc(sbi, bitmap_size, GFP_KERNEL);
3587 	if (!free_i->free_segmap)
3588 		return -ENOMEM;
3589 
3590 	sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
3591 	free_i->free_secmap = f2fs_kvmalloc(sbi, sec_bitmap_size, GFP_KERNEL);
3592 	if (!free_i->free_secmap)
3593 		return -ENOMEM;
3594 
3595 	/* set all segments as dirty temporarily */
3596 	memset(free_i->free_segmap, 0xff, bitmap_size);
3597 	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
3598 
3599 	/* init free segmap information */
3600 	free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
3601 	free_i->free_segments = 0;
3602 	free_i->free_sections = 0;
3603 	spin_lock_init(&free_i->segmap_lock);
3604 	return 0;
3605 }
3606 
3607 static int build_curseg(struct f2fs_sb_info *sbi)
3608 {
3609 	struct curseg_info *array;
3610 	int i;
3611 
3612 	array = f2fs_kzalloc(sbi, sizeof(*array) * NR_CURSEG_TYPE, GFP_KERNEL);
3613 	if (!array)
3614 		return -ENOMEM;
3615 
3616 	SM_I(sbi)->curseg_array = array;
3617 
3618 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
3619 		mutex_init(&array[i].curseg_mutex);
3620 		array[i].sum_blk = f2fs_kzalloc(sbi, PAGE_SIZE, GFP_KERNEL);
3621 		if (!array[i].sum_blk)
3622 			return -ENOMEM;
3623 		init_rwsem(&array[i].journal_rwsem);
3624 		array[i].journal = f2fs_kzalloc(sbi,
3625 				sizeof(struct f2fs_journal), GFP_KERNEL);
3626 		if (!array[i].journal)
3627 			return -ENOMEM;
3628 		array[i].segno = NULL_SEGNO;
3629 		array[i].next_blkoff = 0;
3630 	}
3631 	return restore_curseg_summaries(sbi);
3632 }
3633 
3634 static int build_sit_entries(struct f2fs_sb_info *sbi)
3635 {
3636 	struct sit_info *sit_i = SIT_I(sbi);
3637 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3638 	struct f2fs_journal *journal = curseg->journal;
3639 	struct seg_entry *se;
3640 	struct f2fs_sit_entry sit;
3641 	int sit_blk_cnt = SIT_BLK_CNT(sbi);
3642 	unsigned int i, start, end;
3643 	unsigned int readed, start_blk = 0;
3644 	int err = 0;
3645 	block_t total_node_blocks = 0;
3646 
3647 	do {
3648 		readed = ra_meta_pages(sbi, start_blk, BIO_MAX_PAGES,
3649 							META_SIT, true);
3650 
3651 		start = start_blk * sit_i->sents_per_block;
3652 		end = (start_blk + readed) * sit_i->sents_per_block;
3653 
3654 		for (; start < end && start < MAIN_SEGS(sbi); start++) {
3655 			struct f2fs_sit_block *sit_blk;
3656 			struct page *page;
3657 
3658 			se = &sit_i->sentries[start];
3659 			page = get_current_sit_page(sbi, start);
3660 			sit_blk = (struct f2fs_sit_block *)page_address(page);
3661 			sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
3662 			f2fs_put_page(page, 1);
3663 
3664 			err = check_block_count(sbi, start, &sit);
3665 			if (err)
3666 				return err;
3667 			seg_info_from_raw_sit(se, &sit);
3668 			if (IS_NODESEG(se->type))
3669 				total_node_blocks += se->valid_blocks;
3670 
3671 			/* build discard map only one time */
3672 			if (f2fs_discard_en(sbi)) {
3673 				if (is_set_ckpt_flags(sbi, CP_TRIMMED_FLAG)) {
3674 					memset(se->discard_map, 0xff,
3675 						SIT_VBLOCK_MAP_SIZE);
3676 				} else {
3677 					memcpy(se->discard_map,
3678 						se->cur_valid_map,
3679 						SIT_VBLOCK_MAP_SIZE);
3680 					sbi->discard_blks +=
3681 						sbi->blocks_per_seg -
3682 						se->valid_blocks;
3683 				}
3684 			}
3685 
3686 			if (sbi->segs_per_sec > 1)
3687 				get_sec_entry(sbi, start)->valid_blocks +=
3688 							se->valid_blocks;
3689 		}
3690 		start_blk += readed;
3691 	} while (start_blk < sit_blk_cnt);
3692 
3693 	down_read(&curseg->journal_rwsem);
3694 	for (i = 0; i < sits_in_cursum(journal); i++) {
3695 		unsigned int old_valid_blocks;
3696 
3697 		start = le32_to_cpu(segno_in_journal(journal, i));
3698 		if (start >= MAIN_SEGS(sbi)) {
3699 			f2fs_msg(sbi->sb, KERN_ERR,
3700 					"Wrong journal entry on segno %u",
3701 					start);
3702 			set_sbi_flag(sbi, SBI_NEED_FSCK);
3703 			err = -EINVAL;
3704 			break;
3705 		}
3706 
3707 		se = &sit_i->sentries[start];
3708 		sit = sit_in_journal(journal, i);
3709 
3710 		old_valid_blocks = se->valid_blocks;
3711 		if (IS_NODESEG(se->type))
3712 			total_node_blocks -= old_valid_blocks;
3713 
3714 		err = check_block_count(sbi, start, &sit);
3715 		if (err)
3716 			break;
3717 		seg_info_from_raw_sit(se, &sit);
3718 		if (IS_NODESEG(se->type))
3719 			total_node_blocks += se->valid_blocks;
3720 
3721 		if (f2fs_discard_en(sbi)) {
3722 			if (is_set_ckpt_flags(sbi, CP_TRIMMED_FLAG)) {
3723 				memset(se->discard_map, 0xff,
3724 							SIT_VBLOCK_MAP_SIZE);
3725 			} else {
3726 				memcpy(se->discard_map, se->cur_valid_map,
3727 							SIT_VBLOCK_MAP_SIZE);
3728 				sbi->discard_blks += old_valid_blocks;
3729 				sbi->discard_blks -= se->valid_blocks;
3730 			}
3731 		}
3732 
3733 		if (sbi->segs_per_sec > 1) {
3734 			get_sec_entry(sbi, start)->valid_blocks +=
3735 							se->valid_blocks;
3736 			get_sec_entry(sbi, start)->valid_blocks -=
3737 							old_valid_blocks;
3738 		}
3739 	}
3740 	up_read(&curseg->journal_rwsem);
3741 
3742 	if (!err && total_node_blocks != valid_node_count(sbi)) {
3743 		f2fs_msg(sbi->sb, KERN_ERR,
3744 			"SIT is corrupted node# %u vs %u",
3745 			total_node_blocks, valid_node_count(sbi));
3746 		set_sbi_flag(sbi, SBI_NEED_FSCK);
3747 		err = -EINVAL;
3748 	}
3749 
3750 	return err;
3751 }
3752 
3753 static void init_free_segmap(struct f2fs_sb_info *sbi)
3754 {
3755 	unsigned int start;
3756 	int type;
3757 
3758 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
3759 		struct seg_entry *sentry = get_seg_entry(sbi, start);
3760 		if (!sentry->valid_blocks)
3761 			__set_free(sbi, start);
3762 		else
3763 			SIT_I(sbi)->written_valid_blocks +=
3764 						sentry->valid_blocks;
3765 	}
3766 
3767 	/* set use the current segments */
3768 	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
3769 		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
3770 		__set_test_and_inuse(sbi, curseg_t->segno);
3771 	}
3772 }
3773 
3774 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
3775 {
3776 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3777 	struct free_segmap_info *free_i = FREE_I(sbi);
3778 	unsigned int segno = 0, offset = 0;
3779 	unsigned short valid_blocks;
3780 
3781 	while (1) {
3782 		/* find dirty segment based on free segmap */
3783 		segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
3784 		if (segno >= MAIN_SEGS(sbi))
3785 			break;
3786 		offset = segno + 1;
3787 		valid_blocks = get_valid_blocks(sbi, segno, false);
3788 		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
3789 			continue;
3790 		if (valid_blocks > sbi->blocks_per_seg) {
3791 			f2fs_bug_on(sbi, 1);
3792 			continue;
3793 		}
3794 		mutex_lock(&dirty_i->seglist_lock);
3795 		__locate_dirty_segment(sbi, segno, DIRTY);
3796 		mutex_unlock(&dirty_i->seglist_lock);
3797 	}
3798 }
3799 
3800 static int init_victim_secmap(struct f2fs_sb_info *sbi)
3801 {
3802 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3803 	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
3804 
3805 	dirty_i->victim_secmap = f2fs_kvzalloc(sbi, bitmap_size, GFP_KERNEL);
3806 	if (!dirty_i->victim_secmap)
3807 		return -ENOMEM;
3808 	return 0;
3809 }
3810 
3811 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
3812 {
3813 	struct dirty_seglist_info *dirty_i;
3814 	unsigned int bitmap_size, i;
3815 
3816 	/* allocate memory for dirty segments list information */
3817 	dirty_i = f2fs_kzalloc(sbi, sizeof(struct dirty_seglist_info),
3818 								GFP_KERNEL);
3819 	if (!dirty_i)
3820 		return -ENOMEM;
3821 
3822 	SM_I(sbi)->dirty_info = dirty_i;
3823 	mutex_init(&dirty_i->seglist_lock);
3824 
3825 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3826 
3827 	for (i = 0; i < NR_DIRTY_TYPE; i++) {
3828 		dirty_i->dirty_segmap[i] = f2fs_kvzalloc(sbi, bitmap_size,
3829 								GFP_KERNEL);
3830 		if (!dirty_i->dirty_segmap[i])
3831 			return -ENOMEM;
3832 	}
3833 
3834 	init_dirty_segmap(sbi);
3835 	return init_victim_secmap(sbi);
3836 }
3837 
3838 /*
3839  * Update min, max modified time for cost-benefit GC algorithm
3840  */
3841 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
3842 {
3843 	struct sit_info *sit_i = SIT_I(sbi);
3844 	unsigned int segno;
3845 
3846 	down_write(&sit_i->sentry_lock);
3847 
3848 	sit_i->min_mtime = ULLONG_MAX;
3849 
3850 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
3851 		unsigned int i;
3852 		unsigned long long mtime = 0;
3853 
3854 		for (i = 0; i < sbi->segs_per_sec; i++)
3855 			mtime += get_seg_entry(sbi, segno + i)->mtime;
3856 
3857 		mtime = div_u64(mtime, sbi->segs_per_sec);
3858 
3859 		if (sit_i->min_mtime > mtime)
3860 			sit_i->min_mtime = mtime;
3861 	}
3862 	sit_i->max_mtime = get_mtime(sbi);
3863 	up_write(&sit_i->sentry_lock);
3864 }
3865 
3866 int build_segment_manager(struct f2fs_sb_info *sbi)
3867 {
3868 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
3869 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3870 	struct f2fs_sm_info *sm_info;
3871 	int err;
3872 
3873 	sm_info = f2fs_kzalloc(sbi, sizeof(struct f2fs_sm_info), GFP_KERNEL);
3874 	if (!sm_info)
3875 		return -ENOMEM;
3876 
3877 	/* init sm info */
3878 	sbi->sm_info = sm_info;
3879 	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
3880 	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
3881 	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
3882 	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
3883 	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
3884 	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
3885 	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
3886 	sm_info->rec_prefree_segments = sm_info->main_segments *
3887 					DEF_RECLAIM_PREFREE_SEGMENTS / 100;
3888 	if (sm_info->rec_prefree_segments > DEF_MAX_RECLAIM_PREFREE_SEGMENTS)
3889 		sm_info->rec_prefree_segments = DEF_MAX_RECLAIM_PREFREE_SEGMENTS;
3890 
3891 	if (!test_opt(sbi, LFS))
3892 		sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
3893 	sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
3894 	sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
3895 	sm_info->min_hot_blocks = DEF_MIN_HOT_BLOCKS;
3896 	sm_info->min_ssr_sections = reserved_sections(sbi);
3897 
3898 	INIT_LIST_HEAD(&sm_info->sit_entry_set);
3899 
3900 	init_rwsem(&sm_info->curseg_lock);
3901 
3902 	if (!f2fs_readonly(sbi->sb)) {
3903 		err = create_flush_cmd_control(sbi);
3904 		if (err)
3905 			return err;
3906 	}
3907 
3908 	err = create_discard_cmd_control(sbi);
3909 	if (err)
3910 		return err;
3911 
3912 	err = build_sit_info(sbi);
3913 	if (err)
3914 		return err;
3915 	err = build_free_segmap(sbi);
3916 	if (err)
3917 		return err;
3918 	err = build_curseg(sbi);
3919 	if (err)
3920 		return err;
3921 
3922 	/* reinit free segmap based on SIT */
3923 	err = build_sit_entries(sbi);
3924 	if (err)
3925 		return err;
3926 
3927 	init_free_segmap(sbi);
3928 	err = build_dirty_segmap(sbi);
3929 	if (err)
3930 		return err;
3931 
3932 	init_min_max_mtime(sbi);
3933 	return 0;
3934 }
3935 
3936 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
3937 		enum dirty_type dirty_type)
3938 {
3939 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3940 
3941 	mutex_lock(&dirty_i->seglist_lock);
3942 	kvfree(dirty_i->dirty_segmap[dirty_type]);
3943 	dirty_i->nr_dirty[dirty_type] = 0;
3944 	mutex_unlock(&dirty_i->seglist_lock);
3945 }
3946 
3947 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
3948 {
3949 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3950 	kvfree(dirty_i->victim_secmap);
3951 }
3952 
3953 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
3954 {
3955 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3956 	int i;
3957 
3958 	if (!dirty_i)
3959 		return;
3960 
3961 	/* discard pre-free/dirty segments list */
3962 	for (i = 0; i < NR_DIRTY_TYPE; i++)
3963 		discard_dirty_segmap(sbi, i);
3964 
3965 	destroy_victim_secmap(sbi);
3966 	SM_I(sbi)->dirty_info = NULL;
3967 	kfree(dirty_i);
3968 }
3969 
3970 static void destroy_curseg(struct f2fs_sb_info *sbi)
3971 {
3972 	struct curseg_info *array = SM_I(sbi)->curseg_array;
3973 	int i;
3974 
3975 	if (!array)
3976 		return;
3977 	SM_I(sbi)->curseg_array = NULL;
3978 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
3979 		kfree(array[i].sum_blk);
3980 		kfree(array[i].journal);
3981 	}
3982 	kfree(array);
3983 }
3984 
3985 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
3986 {
3987 	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
3988 	if (!free_i)
3989 		return;
3990 	SM_I(sbi)->free_info = NULL;
3991 	kvfree(free_i->free_segmap);
3992 	kvfree(free_i->free_secmap);
3993 	kfree(free_i);
3994 }
3995 
3996 static void destroy_sit_info(struct f2fs_sb_info *sbi)
3997 {
3998 	struct sit_info *sit_i = SIT_I(sbi);
3999 	unsigned int start;
4000 
4001 	if (!sit_i)
4002 		return;
4003 
4004 	if (sit_i->sentries) {
4005 		for (start = 0; start < MAIN_SEGS(sbi); start++) {
4006 			kfree(sit_i->sentries[start].cur_valid_map);
4007 #ifdef CONFIG_F2FS_CHECK_FS
4008 			kfree(sit_i->sentries[start].cur_valid_map_mir);
4009 #endif
4010 			kfree(sit_i->sentries[start].ckpt_valid_map);
4011 			kfree(sit_i->sentries[start].discard_map);
4012 		}
4013 	}
4014 	kfree(sit_i->tmp_map);
4015 
4016 	kvfree(sit_i->sentries);
4017 	kvfree(sit_i->sec_entries);
4018 	kvfree(sit_i->dirty_sentries_bitmap);
4019 
4020 	SM_I(sbi)->sit_info = NULL;
4021 	kfree(sit_i->sit_bitmap);
4022 #ifdef CONFIG_F2FS_CHECK_FS
4023 	kfree(sit_i->sit_bitmap_mir);
4024 #endif
4025 	kfree(sit_i);
4026 }
4027 
4028 void destroy_segment_manager(struct f2fs_sb_info *sbi)
4029 {
4030 	struct f2fs_sm_info *sm_info = SM_I(sbi);
4031 
4032 	if (!sm_info)
4033 		return;
4034 	destroy_flush_cmd_control(sbi, true);
4035 	destroy_discard_cmd_control(sbi);
4036 	destroy_dirty_segmap(sbi);
4037 	destroy_curseg(sbi);
4038 	destroy_free_segmap(sbi);
4039 	destroy_sit_info(sbi);
4040 	sbi->sm_info = NULL;
4041 	kfree(sm_info);
4042 }
4043 
4044 int __init create_segment_manager_caches(void)
4045 {
4046 	discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
4047 			sizeof(struct discard_entry));
4048 	if (!discard_entry_slab)
4049 		goto fail;
4050 
4051 	discard_cmd_slab = f2fs_kmem_cache_create("discard_cmd",
4052 			sizeof(struct discard_cmd));
4053 	if (!discard_cmd_slab)
4054 		goto destroy_discard_entry;
4055 
4056 	sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
4057 			sizeof(struct sit_entry_set));
4058 	if (!sit_entry_set_slab)
4059 		goto destroy_discard_cmd;
4060 
4061 	inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
4062 			sizeof(struct inmem_pages));
4063 	if (!inmem_entry_slab)
4064 		goto destroy_sit_entry_set;
4065 	return 0;
4066 
4067 destroy_sit_entry_set:
4068 	kmem_cache_destroy(sit_entry_set_slab);
4069 destroy_discard_cmd:
4070 	kmem_cache_destroy(discard_cmd_slab);
4071 destroy_discard_entry:
4072 	kmem_cache_destroy(discard_entry_slab);
4073 fail:
4074 	return -ENOMEM;
4075 }
4076 
4077 void destroy_segment_manager_caches(void)
4078 {
4079 	kmem_cache_destroy(sit_entry_set_slab);
4080 	kmem_cache_destroy(discard_cmd_slab);
4081 	kmem_cache_destroy(discard_entry_slab);
4082 	kmem_cache_destroy(inmem_entry_slab);
4083 }
4084