xref: /openbmc/linux/fs/f2fs/segment.c (revision 67fce70ba341f772073cac9c3044aa98c69b24fb)
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 f2fs_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 f2fs_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 = f2fs_get_dnode_of_data(&dn, page->index,
243 								LOOKUP_NODE);
244 			if (err) {
245 				if (err == -ENOMEM) {
246 					congestion_wait(BLK_RW_ASYNC, HZ/50);
247 					cond_resched();
248 					goto retry;
249 				}
250 				err = -EAGAIN;
251 				goto next;
252 			}
253 			f2fs_get_node_info(sbi, dn.nid, &ni);
254 			if (cur->old_addr == NEW_ADDR) {
255 				f2fs_invalidate_blocks(sbi, dn.data_blkaddr);
256 				f2fs_update_data_blkaddr(&dn, NEW_ADDR);
257 			} else
258 				f2fs_replace_block(sbi, &dn, dn.data_blkaddr,
259 					cur->old_addr, ni.version, true, true);
260 			f2fs_put_dnode(&dn);
261 		}
262 next:
263 		/* we don't need to invalidate this in the sccessful status */
264 		if (drop || recover)
265 			ClearPageUptodate(page);
266 		set_page_private(page, 0);
267 		ClearPagePrivate(page);
268 		f2fs_put_page(page, 1);
269 
270 		list_del(&cur->list);
271 		kmem_cache_free(inmem_entry_slab, cur);
272 		dec_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
273 	}
274 	return err;
275 }
276 
277 void f2fs_drop_inmem_pages_all(struct f2fs_sb_info *sbi, bool gc_failure)
278 {
279 	struct list_head *head = &sbi->inode_list[ATOMIC_FILE];
280 	struct inode *inode;
281 	struct f2fs_inode_info *fi;
282 next:
283 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
284 	if (list_empty(head)) {
285 		spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
286 		return;
287 	}
288 	fi = list_first_entry(head, struct f2fs_inode_info, inmem_ilist);
289 	inode = igrab(&fi->vfs_inode);
290 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
291 
292 	if (inode) {
293 		if (gc_failure) {
294 			if (fi->i_gc_failures[GC_FAILURE_ATOMIC])
295 				goto drop;
296 			goto skip;
297 		}
298 drop:
299 		set_inode_flag(inode, FI_ATOMIC_REVOKE_REQUEST);
300 		f2fs_drop_inmem_pages(inode);
301 		iput(inode);
302 	}
303 skip:
304 	congestion_wait(BLK_RW_ASYNC, HZ/50);
305 	cond_resched();
306 	goto next;
307 }
308 
309 void f2fs_drop_inmem_pages(struct inode *inode)
310 {
311 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
312 	struct f2fs_inode_info *fi = F2FS_I(inode);
313 
314 	mutex_lock(&fi->inmem_lock);
315 	__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
316 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
317 	if (!list_empty(&fi->inmem_ilist))
318 		list_del_init(&fi->inmem_ilist);
319 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
320 	mutex_unlock(&fi->inmem_lock);
321 
322 	clear_inode_flag(inode, FI_ATOMIC_FILE);
323 	fi->i_gc_failures[GC_FAILURE_ATOMIC] = 0;
324 	stat_dec_atomic_write(inode);
325 }
326 
327 void f2fs_drop_inmem_page(struct inode *inode, struct page *page)
328 {
329 	struct f2fs_inode_info *fi = F2FS_I(inode);
330 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
331 	struct list_head *head = &fi->inmem_pages;
332 	struct inmem_pages *cur = NULL;
333 
334 	f2fs_bug_on(sbi, !IS_ATOMIC_WRITTEN_PAGE(page));
335 
336 	mutex_lock(&fi->inmem_lock);
337 	list_for_each_entry(cur, head, list) {
338 		if (cur->page == page)
339 			break;
340 	}
341 
342 	f2fs_bug_on(sbi, list_empty(head) || cur->page != page);
343 	list_del(&cur->list);
344 	mutex_unlock(&fi->inmem_lock);
345 
346 	dec_page_count(sbi, F2FS_INMEM_PAGES);
347 	kmem_cache_free(inmem_entry_slab, cur);
348 
349 	ClearPageUptodate(page);
350 	set_page_private(page, 0);
351 	ClearPagePrivate(page);
352 	f2fs_put_page(page, 0);
353 
354 	trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE);
355 }
356 
357 static int __f2fs_commit_inmem_pages(struct inode *inode)
358 {
359 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
360 	struct f2fs_inode_info *fi = F2FS_I(inode);
361 	struct inmem_pages *cur, *tmp;
362 	struct f2fs_io_info fio = {
363 		.sbi = sbi,
364 		.ino = inode->i_ino,
365 		.type = DATA,
366 		.op = REQ_OP_WRITE,
367 		.op_flags = REQ_SYNC | REQ_PRIO,
368 		.io_type = FS_DATA_IO,
369 	};
370 	struct list_head revoke_list;
371 	pgoff_t last_idx = ULONG_MAX;
372 	int err = 0;
373 
374 	INIT_LIST_HEAD(&revoke_list);
375 
376 	list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
377 		struct page *page = cur->page;
378 
379 		lock_page(page);
380 		if (page->mapping == inode->i_mapping) {
381 			trace_f2fs_commit_inmem_page(page, INMEM);
382 
383 			set_page_dirty(page);
384 			f2fs_wait_on_page_writeback(page, DATA, true);
385 			if (clear_page_dirty_for_io(page)) {
386 				inode_dec_dirty_pages(inode);
387 				f2fs_remove_dirty_inode(inode);
388 			}
389 retry:
390 			fio.page = page;
391 			fio.old_blkaddr = NULL_ADDR;
392 			fio.encrypted_page = NULL;
393 			fio.need_lock = LOCK_DONE;
394 			err = f2fs_do_write_data_page(&fio);
395 			if (err) {
396 				if (err == -ENOMEM) {
397 					congestion_wait(BLK_RW_ASYNC, HZ/50);
398 					cond_resched();
399 					goto retry;
400 				}
401 				unlock_page(page);
402 				break;
403 			}
404 			/* record old blkaddr for revoking */
405 			cur->old_addr = fio.old_blkaddr;
406 			last_idx = page->index;
407 		}
408 		unlock_page(page);
409 		list_move_tail(&cur->list, &revoke_list);
410 	}
411 
412 	if (last_idx != ULONG_MAX)
413 		f2fs_submit_merged_write_cond(sbi, inode, 0, last_idx, DATA);
414 
415 	if (err) {
416 		/*
417 		 * try to revoke all committed pages, but still we could fail
418 		 * due to no memory or other reason, if that happened, EAGAIN
419 		 * will be returned, which means in such case, transaction is
420 		 * already not integrity, caller should use journal to do the
421 		 * recovery or rewrite & commit last transaction. For other
422 		 * error number, revoking was done by filesystem itself.
423 		 */
424 		err = __revoke_inmem_pages(inode, &revoke_list, false, true);
425 
426 		/* drop all uncommitted pages */
427 		__revoke_inmem_pages(inode, &fi->inmem_pages, true, false);
428 	} else {
429 		__revoke_inmem_pages(inode, &revoke_list, false, false);
430 	}
431 
432 	return err;
433 }
434 
435 int f2fs_commit_inmem_pages(struct inode *inode)
436 {
437 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
438 	struct f2fs_inode_info *fi = F2FS_I(inode);
439 	int err;
440 
441 	f2fs_balance_fs(sbi, true);
442 	f2fs_lock_op(sbi);
443 
444 	set_inode_flag(inode, FI_ATOMIC_COMMIT);
445 
446 	mutex_lock(&fi->inmem_lock);
447 	err = __f2fs_commit_inmem_pages(inode);
448 
449 	spin_lock(&sbi->inode_lock[ATOMIC_FILE]);
450 	if (!list_empty(&fi->inmem_ilist))
451 		list_del_init(&fi->inmem_ilist);
452 	spin_unlock(&sbi->inode_lock[ATOMIC_FILE]);
453 	mutex_unlock(&fi->inmem_lock);
454 
455 	clear_inode_flag(inode, FI_ATOMIC_COMMIT);
456 
457 	f2fs_unlock_op(sbi);
458 	return err;
459 }
460 
461 /*
462  * This function balances dirty node and dentry pages.
463  * In addition, it controls garbage collection.
464  */
465 void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
466 {
467 #ifdef CONFIG_F2FS_FAULT_INJECTION
468 	if (time_to_inject(sbi, FAULT_CHECKPOINT)) {
469 		f2fs_show_injection_info(FAULT_CHECKPOINT);
470 		f2fs_stop_checkpoint(sbi, false);
471 	}
472 #endif
473 
474 	/* balance_fs_bg is able to be pending */
475 	if (need && excess_cached_nats(sbi))
476 		f2fs_balance_fs_bg(sbi);
477 
478 	/*
479 	 * We should do GC or end up with checkpoint, if there are so many dirty
480 	 * dir/node pages without enough free segments.
481 	 */
482 	if (has_not_enough_free_secs(sbi, 0, 0)) {
483 		mutex_lock(&sbi->gc_mutex);
484 		f2fs_gc(sbi, false, false, NULL_SEGNO);
485 	}
486 }
487 
488 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
489 {
490 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
491 		return;
492 
493 	/* try to shrink extent cache when there is no enough memory */
494 	if (!f2fs_available_free_memory(sbi, EXTENT_CACHE))
495 		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
496 
497 	/* check the # of cached NAT entries */
498 	if (!f2fs_available_free_memory(sbi, NAT_ENTRIES))
499 		f2fs_try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
500 
501 	if (!f2fs_available_free_memory(sbi, FREE_NIDS))
502 		f2fs_try_to_free_nids(sbi, MAX_FREE_NIDS);
503 	else
504 		f2fs_build_free_nids(sbi, false, false);
505 
506 	if (!is_idle(sbi) && !excess_dirty_nats(sbi))
507 		return;
508 
509 	/* checkpoint is the only way to shrink partial cached entries */
510 	if (!f2fs_available_free_memory(sbi, NAT_ENTRIES) ||
511 			!f2fs_available_free_memory(sbi, INO_ENTRIES) ||
512 			excess_prefree_segs(sbi) ||
513 			excess_dirty_nats(sbi) ||
514 			f2fs_time_over(sbi, CP_TIME)) {
515 		if (test_opt(sbi, DATA_FLUSH)) {
516 			struct blk_plug plug;
517 
518 			blk_start_plug(&plug);
519 			f2fs_sync_dirty_inodes(sbi, FILE_INODE);
520 			blk_finish_plug(&plug);
521 		}
522 		f2fs_sync_fs(sbi->sb, true);
523 		stat_inc_bg_cp_count(sbi->stat_info);
524 	}
525 }
526 
527 static int __submit_flush_wait(struct f2fs_sb_info *sbi,
528 				struct block_device *bdev)
529 {
530 	struct bio *bio = f2fs_bio_alloc(sbi, 0, true);
531 	int ret;
532 
533 	bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH;
534 	bio_set_dev(bio, bdev);
535 	ret = submit_bio_wait(bio);
536 	bio_put(bio);
537 
538 	trace_f2fs_issue_flush(bdev, test_opt(sbi, NOBARRIER),
539 				test_opt(sbi, FLUSH_MERGE), ret);
540 	return ret;
541 }
542 
543 static int submit_flush_wait(struct f2fs_sb_info *sbi, nid_t ino)
544 {
545 	int ret = 0;
546 	int i;
547 
548 	if (!sbi->s_ndevs)
549 		return __submit_flush_wait(sbi, sbi->sb->s_bdev);
550 
551 	for (i = 0; i < sbi->s_ndevs; i++) {
552 		if (!f2fs_is_dirty_device(sbi, ino, i, FLUSH_INO))
553 			continue;
554 		ret = __submit_flush_wait(sbi, FDEV(i).bdev);
555 		if (ret)
556 			break;
557 	}
558 	return ret;
559 }
560 
561 static int issue_flush_thread(void *data)
562 {
563 	struct f2fs_sb_info *sbi = data;
564 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
565 	wait_queue_head_t *q = &fcc->flush_wait_queue;
566 repeat:
567 	if (kthread_should_stop())
568 		return 0;
569 
570 	sb_start_intwrite(sbi->sb);
571 
572 	if (!llist_empty(&fcc->issue_list)) {
573 		struct flush_cmd *cmd, *next;
574 		int ret;
575 
576 		fcc->dispatch_list = llist_del_all(&fcc->issue_list);
577 		fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
578 
579 		cmd = llist_entry(fcc->dispatch_list, struct flush_cmd, llnode);
580 
581 		ret = submit_flush_wait(sbi, cmd->ino);
582 		atomic_inc(&fcc->issued_flush);
583 
584 		llist_for_each_entry_safe(cmd, next,
585 					  fcc->dispatch_list, llnode) {
586 			cmd->ret = ret;
587 			complete(&cmd->wait);
588 		}
589 		fcc->dispatch_list = NULL;
590 	}
591 
592 	sb_end_intwrite(sbi->sb);
593 
594 	wait_event_interruptible(*q,
595 		kthread_should_stop() || !llist_empty(&fcc->issue_list));
596 	goto repeat;
597 }
598 
599 int f2fs_issue_flush(struct f2fs_sb_info *sbi, nid_t ino)
600 {
601 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
602 	struct flush_cmd cmd;
603 	int ret;
604 
605 	if (test_opt(sbi, NOBARRIER))
606 		return 0;
607 
608 	if (!test_opt(sbi, FLUSH_MERGE)) {
609 		ret = submit_flush_wait(sbi, ino);
610 		atomic_inc(&fcc->issued_flush);
611 		return ret;
612 	}
613 
614 	if (atomic_inc_return(&fcc->issing_flush) == 1 || sbi->s_ndevs > 1) {
615 		ret = submit_flush_wait(sbi, ino);
616 		atomic_dec(&fcc->issing_flush);
617 
618 		atomic_inc(&fcc->issued_flush);
619 		return ret;
620 	}
621 
622 	cmd.ino = ino;
623 	init_completion(&cmd.wait);
624 
625 	llist_add(&cmd.llnode, &fcc->issue_list);
626 
627 	/* update issue_list before we wake up issue_flush thread */
628 	smp_mb();
629 
630 	if (waitqueue_active(&fcc->flush_wait_queue))
631 		wake_up(&fcc->flush_wait_queue);
632 
633 	if (fcc->f2fs_issue_flush) {
634 		wait_for_completion(&cmd.wait);
635 		atomic_dec(&fcc->issing_flush);
636 	} else {
637 		struct llist_node *list;
638 
639 		list = llist_del_all(&fcc->issue_list);
640 		if (!list) {
641 			wait_for_completion(&cmd.wait);
642 			atomic_dec(&fcc->issing_flush);
643 		} else {
644 			struct flush_cmd *tmp, *next;
645 
646 			ret = submit_flush_wait(sbi, ino);
647 
648 			llist_for_each_entry_safe(tmp, next, list, llnode) {
649 				if (tmp == &cmd) {
650 					cmd.ret = ret;
651 					atomic_dec(&fcc->issing_flush);
652 					continue;
653 				}
654 				tmp->ret = ret;
655 				complete(&tmp->wait);
656 			}
657 		}
658 	}
659 
660 	return cmd.ret;
661 }
662 
663 int f2fs_create_flush_cmd_control(struct f2fs_sb_info *sbi)
664 {
665 	dev_t dev = sbi->sb->s_bdev->bd_dev;
666 	struct flush_cmd_control *fcc;
667 	int err = 0;
668 
669 	if (SM_I(sbi)->fcc_info) {
670 		fcc = SM_I(sbi)->fcc_info;
671 		if (fcc->f2fs_issue_flush)
672 			return err;
673 		goto init_thread;
674 	}
675 
676 	fcc = f2fs_kzalloc(sbi, sizeof(struct flush_cmd_control), GFP_KERNEL);
677 	if (!fcc)
678 		return -ENOMEM;
679 	atomic_set(&fcc->issued_flush, 0);
680 	atomic_set(&fcc->issing_flush, 0);
681 	init_waitqueue_head(&fcc->flush_wait_queue);
682 	init_llist_head(&fcc->issue_list);
683 	SM_I(sbi)->fcc_info = fcc;
684 	if (!test_opt(sbi, FLUSH_MERGE))
685 		return err;
686 
687 init_thread:
688 	fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
689 				"f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
690 	if (IS_ERR(fcc->f2fs_issue_flush)) {
691 		err = PTR_ERR(fcc->f2fs_issue_flush);
692 		kfree(fcc);
693 		SM_I(sbi)->fcc_info = NULL;
694 		return err;
695 	}
696 
697 	return err;
698 }
699 
700 void f2fs_destroy_flush_cmd_control(struct f2fs_sb_info *sbi, bool free)
701 {
702 	struct flush_cmd_control *fcc = SM_I(sbi)->fcc_info;
703 
704 	if (fcc && fcc->f2fs_issue_flush) {
705 		struct task_struct *flush_thread = fcc->f2fs_issue_flush;
706 
707 		fcc->f2fs_issue_flush = NULL;
708 		kthread_stop(flush_thread);
709 	}
710 	if (free) {
711 		kfree(fcc);
712 		SM_I(sbi)->fcc_info = NULL;
713 	}
714 }
715 
716 int f2fs_flush_device_cache(struct f2fs_sb_info *sbi)
717 {
718 	int ret = 0, i;
719 
720 	if (!sbi->s_ndevs)
721 		return 0;
722 
723 	for (i = 1; i < sbi->s_ndevs; i++) {
724 		if (!f2fs_test_bit(i, (char *)&sbi->dirty_device))
725 			continue;
726 		ret = __submit_flush_wait(sbi, FDEV(i).bdev);
727 		if (ret)
728 			break;
729 
730 		spin_lock(&sbi->dev_lock);
731 		f2fs_clear_bit(i, (char *)&sbi->dirty_device);
732 		spin_unlock(&sbi->dev_lock);
733 	}
734 
735 	return ret;
736 }
737 
738 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
739 		enum dirty_type dirty_type)
740 {
741 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
742 
743 	/* need not be added */
744 	if (IS_CURSEG(sbi, segno))
745 		return;
746 
747 	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
748 		dirty_i->nr_dirty[dirty_type]++;
749 
750 	if (dirty_type == DIRTY) {
751 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
752 		enum dirty_type t = sentry->type;
753 
754 		if (unlikely(t >= DIRTY)) {
755 			f2fs_bug_on(sbi, 1);
756 			return;
757 		}
758 		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
759 			dirty_i->nr_dirty[t]++;
760 	}
761 }
762 
763 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
764 		enum dirty_type dirty_type)
765 {
766 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
767 
768 	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
769 		dirty_i->nr_dirty[dirty_type]--;
770 
771 	if (dirty_type == DIRTY) {
772 		struct seg_entry *sentry = get_seg_entry(sbi, segno);
773 		enum dirty_type t = sentry->type;
774 
775 		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
776 			dirty_i->nr_dirty[t]--;
777 
778 		if (get_valid_blocks(sbi, segno, true) == 0)
779 			clear_bit(GET_SEC_FROM_SEG(sbi, segno),
780 						dirty_i->victim_secmap);
781 	}
782 }
783 
784 /*
785  * Should not occur error such as -ENOMEM.
786  * Adding dirty entry into seglist is not critical operation.
787  * If a given segment is one of current working segments, it won't be added.
788  */
789 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
790 {
791 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
792 	unsigned short valid_blocks;
793 
794 	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
795 		return;
796 
797 	mutex_lock(&dirty_i->seglist_lock);
798 
799 	valid_blocks = get_valid_blocks(sbi, segno, false);
800 
801 	if (valid_blocks == 0) {
802 		__locate_dirty_segment(sbi, segno, PRE);
803 		__remove_dirty_segment(sbi, segno, DIRTY);
804 	} else if (valid_blocks < sbi->blocks_per_seg) {
805 		__locate_dirty_segment(sbi, segno, DIRTY);
806 	} else {
807 		/* Recovery routine with SSR needs this */
808 		__remove_dirty_segment(sbi, segno, DIRTY);
809 	}
810 
811 	mutex_unlock(&dirty_i->seglist_lock);
812 }
813 
814 static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
815 		struct block_device *bdev, block_t lstart,
816 		block_t start, block_t len)
817 {
818 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
819 	struct list_head *pend_list;
820 	struct discard_cmd *dc;
821 
822 	f2fs_bug_on(sbi, !len);
823 
824 	pend_list = &dcc->pend_list[plist_idx(len)];
825 
826 	dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS);
827 	INIT_LIST_HEAD(&dc->list);
828 	dc->bdev = bdev;
829 	dc->lstart = lstart;
830 	dc->start = start;
831 	dc->len = len;
832 	dc->ref = 0;
833 	dc->state = D_PREP;
834 	dc->error = 0;
835 	init_completion(&dc->wait);
836 	list_add_tail(&dc->list, pend_list);
837 	atomic_inc(&dcc->discard_cmd_cnt);
838 	dcc->undiscard_blks += len;
839 
840 	return dc;
841 }
842 
843 static struct discard_cmd *__attach_discard_cmd(struct f2fs_sb_info *sbi,
844 				struct block_device *bdev, block_t lstart,
845 				block_t start, block_t len,
846 				struct rb_node *parent, struct rb_node **p)
847 {
848 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
849 	struct discard_cmd *dc;
850 
851 	dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
852 
853 	rb_link_node(&dc->rb_node, parent, p);
854 	rb_insert_color(&dc->rb_node, &dcc->root);
855 
856 	return dc;
857 }
858 
859 static void __detach_discard_cmd(struct discard_cmd_control *dcc,
860 							struct discard_cmd *dc)
861 {
862 	if (dc->state == D_DONE)
863 		atomic_dec(&dcc->issing_discard);
864 
865 	list_del(&dc->list);
866 	rb_erase(&dc->rb_node, &dcc->root);
867 	dcc->undiscard_blks -= dc->len;
868 
869 	kmem_cache_free(discard_cmd_slab, dc);
870 
871 	atomic_dec(&dcc->discard_cmd_cnt);
872 }
873 
874 static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
875 							struct discard_cmd *dc)
876 {
877 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
878 
879 	trace_f2fs_remove_discard(dc->bdev, dc->start, dc->len);
880 
881 	f2fs_bug_on(sbi, dc->ref);
882 
883 	if (dc->error == -EOPNOTSUPP)
884 		dc->error = 0;
885 
886 	if (dc->error)
887 		f2fs_msg(sbi->sb, KERN_INFO,
888 			"Issue discard(%u, %u, %u) failed, ret: %d",
889 			dc->lstart, dc->start, dc->len, dc->error);
890 	__detach_discard_cmd(dcc, dc);
891 }
892 
893 static void f2fs_submit_discard_endio(struct bio *bio)
894 {
895 	struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
896 
897 	dc->error = blk_status_to_errno(bio->bi_status);
898 	dc->state = D_DONE;
899 	complete_all(&dc->wait);
900 	bio_put(bio);
901 }
902 
903 static void __check_sit_bitmap(struct f2fs_sb_info *sbi,
904 				block_t start, block_t end)
905 {
906 #ifdef CONFIG_F2FS_CHECK_FS
907 	struct seg_entry *sentry;
908 	unsigned int segno;
909 	block_t blk = start;
910 	unsigned long offset, size, max_blocks = sbi->blocks_per_seg;
911 	unsigned long *map;
912 
913 	while (blk < end) {
914 		segno = GET_SEGNO(sbi, blk);
915 		sentry = get_seg_entry(sbi, segno);
916 		offset = GET_BLKOFF_FROM_SEG0(sbi, blk);
917 
918 		if (end < START_BLOCK(sbi, segno + 1))
919 			size = GET_BLKOFF_FROM_SEG0(sbi, end);
920 		else
921 			size = max_blocks;
922 		map = (unsigned long *)(sentry->cur_valid_map);
923 		offset = __find_rev_next_bit(map, size, offset);
924 		f2fs_bug_on(sbi, offset != size);
925 		blk = START_BLOCK(sbi, segno + 1);
926 	}
927 #endif
928 }
929 
930 static void __init_discard_policy(struct f2fs_sb_info *sbi,
931 				struct discard_policy *dpolicy,
932 				int discard_type, unsigned int granularity)
933 {
934 	/* common policy */
935 	dpolicy->type = discard_type;
936 	dpolicy->sync = true;
937 	dpolicy->granularity = granularity;
938 
939 	dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
940 	dpolicy->io_aware_gran = MAX_PLIST_NUM;
941 
942 	if (discard_type == DPOLICY_BG) {
943 		dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
944 		dpolicy->mid_interval = DEF_MID_DISCARD_ISSUE_TIME;
945 		dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
946 		dpolicy->io_aware = true;
947 		dpolicy->sync = false;
948 		if (utilization(sbi) > DEF_DISCARD_URGENT_UTIL) {
949 			dpolicy->granularity = 1;
950 			dpolicy->max_interval = DEF_MIN_DISCARD_ISSUE_TIME;
951 		}
952 	} else if (discard_type == DPOLICY_FORCE) {
953 		dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME;
954 		dpolicy->mid_interval = DEF_MID_DISCARD_ISSUE_TIME;
955 		dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
956 		dpolicy->io_aware = false;
957 	} else if (discard_type == DPOLICY_FSTRIM) {
958 		dpolicy->io_aware = false;
959 	} else if (discard_type == DPOLICY_UMOUNT) {
960 		dpolicy->max_requests = UINT_MAX;
961 		dpolicy->io_aware = false;
962 	}
963 }
964 
965 
966 /* this function is copied from blkdev_issue_discard from block/blk-lib.c */
967 static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
968 						struct discard_policy *dpolicy,
969 						struct discard_cmd *dc)
970 {
971 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
972 	struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ?
973 					&(dcc->fstrim_list) : &(dcc->wait_list);
974 	struct bio *bio = NULL;
975 	int flag = dpolicy->sync ? REQ_SYNC : 0;
976 
977 	if (dc->state != D_PREP)
978 		return;
979 
980 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
981 		return;
982 
983 	trace_f2fs_issue_discard(dc->bdev, dc->start, dc->len);
984 
985 	dc->error = __blkdev_issue_discard(dc->bdev,
986 				SECTOR_FROM_BLOCK(dc->start),
987 				SECTOR_FROM_BLOCK(dc->len),
988 				GFP_NOFS, 0, &bio);
989 	if (!dc->error) {
990 		/* should keep before submission to avoid D_DONE right away */
991 		dc->state = D_SUBMIT;
992 		atomic_inc(&dcc->issued_discard);
993 		atomic_inc(&dcc->issing_discard);
994 		if (bio) {
995 			bio->bi_private = dc;
996 			bio->bi_end_io = f2fs_submit_discard_endio;
997 			bio->bi_opf |= flag;
998 			submit_bio(bio);
999 			list_move_tail(&dc->list, wait_list);
1000 			__check_sit_bitmap(sbi, dc->start, dc->start + dc->len);
1001 
1002 			f2fs_update_iostat(sbi, FS_DISCARD, 1);
1003 		}
1004 	} else {
1005 		__remove_discard_cmd(sbi, dc);
1006 	}
1007 }
1008 
1009 static struct discard_cmd *__insert_discard_tree(struct f2fs_sb_info *sbi,
1010 				struct block_device *bdev, block_t lstart,
1011 				block_t start, block_t len,
1012 				struct rb_node **insert_p,
1013 				struct rb_node *insert_parent)
1014 {
1015 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1016 	struct rb_node **p;
1017 	struct rb_node *parent = NULL;
1018 	struct discard_cmd *dc = NULL;
1019 
1020 	if (insert_p && insert_parent) {
1021 		parent = insert_parent;
1022 		p = insert_p;
1023 		goto do_insert;
1024 	}
1025 
1026 	p = f2fs_lookup_rb_tree_for_insert(sbi, &dcc->root, &parent, lstart);
1027 do_insert:
1028 	dc = __attach_discard_cmd(sbi, bdev, lstart, start, len, parent, p);
1029 	if (!dc)
1030 		return NULL;
1031 
1032 	return dc;
1033 }
1034 
1035 static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
1036 						struct discard_cmd *dc)
1037 {
1038 	list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
1039 }
1040 
1041 static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
1042 				struct discard_cmd *dc, block_t blkaddr)
1043 {
1044 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1045 	struct discard_info di = dc->di;
1046 	bool modified = false;
1047 
1048 	if (dc->state == D_DONE || dc->len == 1) {
1049 		__remove_discard_cmd(sbi, dc);
1050 		return;
1051 	}
1052 
1053 	dcc->undiscard_blks -= di.len;
1054 
1055 	if (blkaddr > di.lstart) {
1056 		dc->len = blkaddr - dc->lstart;
1057 		dcc->undiscard_blks += dc->len;
1058 		__relocate_discard_cmd(dcc, dc);
1059 		modified = true;
1060 	}
1061 
1062 	if (blkaddr < di.lstart + di.len - 1) {
1063 		if (modified) {
1064 			__insert_discard_tree(sbi, dc->bdev, blkaddr + 1,
1065 					di.start + blkaddr + 1 - di.lstart,
1066 					di.lstart + di.len - 1 - blkaddr,
1067 					NULL, NULL);
1068 		} else {
1069 			dc->lstart++;
1070 			dc->len--;
1071 			dc->start++;
1072 			dcc->undiscard_blks += dc->len;
1073 			__relocate_discard_cmd(dcc, dc);
1074 		}
1075 	}
1076 }
1077 
1078 static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
1079 				struct block_device *bdev, block_t lstart,
1080 				block_t start, block_t len)
1081 {
1082 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1083 	struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
1084 	struct discard_cmd *dc;
1085 	struct discard_info di = {0};
1086 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
1087 	block_t end = lstart + len;
1088 
1089 	mutex_lock(&dcc->cmd_lock);
1090 
1091 	dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
1092 					NULL, lstart,
1093 					(struct rb_entry **)&prev_dc,
1094 					(struct rb_entry **)&next_dc,
1095 					&insert_p, &insert_parent, true);
1096 	if (dc)
1097 		prev_dc = dc;
1098 
1099 	if (!prev_dc) {
1100 		di.lstart = lstart;
1101 		di.len = next_dc ? next_dc->lstart - lstart : len;
1102 		di.len = min(di.len, len);
1103 		di.start = start;
1104 	}
1105 
1106 	while (1) {
1107 		struct rb_node *node;
1108 		bool merged = false;
1109 		struct discard_cmd *tdc = NULL;
1110 
1111 		if (prev_dc) {
1112 			di.lstart = prev_dc->lstart + prev_dc->len;
1113 			if (di.lstart < lstart)
1114 				di.lstart = lstart;
1115 			if (di.lstart >= end)
1116 				break;
1117 
1118 			if (!next_dc || next_dc->lstart > end)
1119 				di.len = end - di.lstart;
1120 			else
1121 				di.len = next_dc->lstart - di.lstart;
1122 			di.start = start + di.lstart - lstart;
1123 		}
1124 
1125 		if (!di.len)
1126 			goto next;
1127 
1128 		if (prev_dc && prev_dc->state == D_PREP &&
1129 			prev_dc->bdev == bdev &&
1130 			__is_discard_back_mergeable(&di, &prev_dc->di)) {
1131 			prev_dc->di.len += di.len;
1132 			dcc->undiscard_blks += di.len;
1133 			__relocate_discard_cmd(dcc, prev_dc);
1134 			di = prev_dc->di;
1135 			tdc = prev_dc;
1136 			merged = true;
1137 		}
1138 
1139 		if (next_dc && next_dc->state == D_PREP &&
1140 			next_dc->bdev == bdev &&
1141 			__is_discard_front_mergeable(&di, &next_dc->di)) {
1142 			next_dc->di.lstart = di.lstart;
1143 			next_dc->di.len += di.len;
1144 			next_dc->di.start = di.start;
1145 			dcc->undiscard_blks += di.len;
1146 			__relocate_discard_cmd(dcc, next_dc);
1147 			if (tdc)
1148 				__remove_discard_cmd(sbi, tdc);
1149 			merged = true;
1150 		}
1151 
1152 		if (!merged) {
1153 			__insert_discard_tree(sbi, bdev, di.lstart, di.start,
1154 							di.len, NULL, NULL);
1155 		}
1156  next:
1157 		prev_dc = next_dc;
1158 		if (!prev_dc)
1159 			break;
1160 
1161 		node = rb_next(&prev_dc->rb_node);
1162 		next_dc = rb_entry_safe(node, struct discard_cmd, rb_node);
1163 	}
1164 
1165 	mutex_unlock(&dcc->cmd_lock);
1166 }
1167 
1168 static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
1169 		struct block_device *bdev, block_t blkstart, block_t blklen)
1170 {
1171 	block_t lblkstart = blkstart;
1172 
1173 	trace_f2fs_queue_discard(bdev, blkstart, blklen);
1174 
1175 	if (sbi->s_ndevs) {
1176 		int devi = f2fs_target_device_index(sbi, blkstart);
1177 
1178 		blkstart -= FDEV(devi).start_blk;
1179 	}
1180 	__update_discard_tree_range(sbi, bdev, lblkstart, blkstart, blklen);
1181 	return 0;
1182 }
1183 
1184 static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
1185 					struct discard_policy *dpolicy)
1186 {
1187 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1188 	struct list_head *pend_list;
1189 	struct discard_cmd *dc, *tmp;
1190 	struct blk_plug plug;
1191 	int i, iter = 0, issued = 0;
1192 	bool io_interrupted = false;
1193 
1194 	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
1195 		if (i + 1 < dpolicy->granularity)
1196 			break;
1197 		pend_list = &dcc->pend_list[i];
1198 
1199 		mutex_lock(&dcc->cmd_lock);
1200 		if (list_empty(pend_list))
1201 			goto next;
1202 		if (unlikely(dcc->rbtree_check))
1203 			f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
1204 								&dcc->root));
1205 		blk_start_plug(&plug);
1206 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
1207 			f2fs_bug_on(sbi, dc->state != D_PREP);
1208 
1209 			if (dpolicy->io_aware && i < dpolicy->io_aware_gran &&
1210 								!is_idle(sbi)) {
1211 				io_interrupted = true;
1212 				goto skip;
1213 			}
1214 
1215 			__submit_discard_cmd(sbi, dpolicy, dc);
1216 			issued++;
1217 skip:
1218 			if (++iter >= dpolicy->max_requests)
1219 				break;
1220 		}
1221 		blk_finish_plug(&plug);
1222 next:
1223 		mutex_unlock(&dcc->cmd_lock);
1224 
1225 		if (iter >= dpolicy->max_requests)
1226 			break;
1227 	}
1228 
1229 	if (!issued && io_interrupted)
1230 		issued = -1;
1231 
1232 	return issued;
1233 }
1234 
1235 static bool __drop_discard_cmd(struct f2fs_sb_info *sbi)
1236 {
1237 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1238 	struct list_head *pend_list;
1239 	struct discard_cmd *dc, *tmp;
1240 	int i;
1241 	bool dropped = false;
1242 
1243 	mutex_lock(&dcc->cmd_lock);
1244 	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
1245 		pend_list = &dcc->pend_list[i];
1246 		list_for_each_entry_safe(dc, tmp, pend_list, list) {
1247 			f2fs_bug_on(sbi, dc->state != D_PREP);
1248 			__remove_discard_cmd(sbi, dc);
1249 			dropped = true;
1250 		}
1251 	}
1252 	mutex_unlock(&dcc->cmd_lock);
1253 
1254 	return dropped;
1255 }
1256 
1257 void f2fs_drop_discard_cmd(struct f2fs_sb_info *sbi)
1258 {
1259 	__drop_discard_cmd(sbi);
1260 }
1261 
1262 static unsigned int __wait_one_discard_bio(struct f2fs_sb_info *sbi,
1263 							struct discard_cmd *dc)
1264 {
1265 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1266 	unsigned int len = 0;
1267 
1268 	wait_for_completion_io(&dc->wait);
1269 	mutex_lock(&dcc->cmd_lock);
1270 	f2fs_bug_on(sbi, dc->state != D_DONE);
1271 	dc->ref--;
1272 	if (!dc->ref) {
1273 		if (!dc->error)
1274 			len = dc->len;
1275 		__remove_discard_cmd(sbi, dc);
1276 	}
1277 	mutex_unlock(&dcc->cmd_lock);
1278 
1279 	return len;
1280 }
1281 
1282 static unsigned int __wait_discard_cmd_range(struct f2fs_sb_info *sbi,
1283 						struct discard_policy *dpolicy,
1284 						block_t start, block_t end)
1285 {
1286 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1287 	struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ?
1288 					&(dcc->fstrim_list) : &(dcc->wait_list);
1289 	struct discard_cmd *dc, *tmp;
1290 	bool need_wait;
1291 	unsigned int trimmed = 0;
1292 
1293 next:
1294 	need_wait = false;
1295 
1296 	mutex_lock(&dcc->cmd_lock);
1297 	list_for_each_entry_safe(dc, tmp, wait_list, list) {
1298 		if (dc->lstart + dc->len <= start || end <= dc->lstart)
1299 			continue;
1300 		if (dc->len < dpolicy->granularity)
1301 			continue;
1302 		if (dc->state == D_DONE && !dc->ref) {
1303 			wait_for_completion_io(&dc->wait);
1304 			if (!dc->error)
1305 				trimmed += dc->len;
1306 			__remove_discard_cmd(sbi, dc);
1307 		} else {
1308 			dc->ref++;
1309 			need_wait = true;
1310 			break;
1311 		}
1312 	}
1313 	mutex_unlock(&dcc->cmd_lock);
1314 
1315 	if (need_wait) {
1316 		trimmed += __wait_one_discard_bio(sbi, dc);
1317 		goto next;
1318 	}
1319 
1320 	return trimmed;
1321 }
1322 
1323 static void __wait_all_discard_cmd(struct f2fs_sb_info *sbi,
1324 						struct discard_policy *dpolicy)
1325 {
1326 	struct discard_policy dp;
1327 
1328 	if (dpolicy) {
1329 		__wait_discard_cmd_range(sbi, dpolicy, 0, UINT_MAX);
1330 		return;
1331 	}
1332 
1333 	/* wait all */
1334 	__init_discard_policy(sbi, &dp, DPOLICY_FSTRIM, 1);
1335 	__wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX);
1336 	__init_discard_policy(sbi, &dp, DPOLICY_UMOUNT, 1);
1337 	__wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX);
1338 }
1339 
1340 /* This should be covered by global mutex, &sit_i->sentry_lock */
1341 static void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
1342 {
1343 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1344 	struct discard_cmd *dc;
1345 	bool need_wait = false;
1346 
1347 	mutex_lock(&dcc->cmd_lock);
1348 	dc = (struct discard_cmd *)f2fs_lookup_rb_tree(&dcc->root,
1349 							NULL, blkaddr);
1350 	if (dc) {
1351 		if (dc->state == D_PREP) {
1352 			__punch_discard_cmd(sbi, dc, blkaddr);
1353 		} else {
1354 			dc->ref++;
1355 			need_wait = true;
1356 		}
1357 	}
1358 	mutex_unlock(&dcc->cmd_lock);
1359 
1360 	if (need_wait)
1361 		__wait_one_discard_bio(sbi, dc);
1362 }
1363 
1364 void f2fs_stop_discard_thread(struct f2fs_sb_info *sbi)
1365 {
1366 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1367 
1368 	if (dcc && dcc->f2fs_issue_discard) {
1369 		struct task_struct *discard_thread = dcc->f2fs_issue_discard;
1370 
1371 		dcc->f2fs_issue_discard = NULL;
1372 		kthread_stop(discard_thread);
1373 	}
1374 }
1375 
1376 /* This comes from f2fs_put_super */
1377 bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
1378 {
1379 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1380 	struct discard_policy dpolicy;
1381 	bool dropped;
1382 
1383 	__init_discard_policy(sbi, &dpolicy, DPOLICY_UMOUNT,
1384 					dcc->discard_granularity);
1385 	__issue_discard_cmd(sbi, &dpolicy);
1386 	dropped = __drop_discard_cmd(sbi);
1387 
1388 	/* just to make sure there is no pending discard commands */
1389 	__wait_all_discard_cmd(sbi, NULL);
1390 	return dropped;
1391 }
1392 
1393 static int issue_discard_thread(void *data)
1394 {
1395 	struct f2fs_sb_info *sbi = data;
1396 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1397 	wait_queue_head_t *q = &dcc->discard_wait_queue;
1398 	struct discard_policy dpolicy;
1399 	unsigned int wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
1400 	int issued;
1401 
1402 	set_freezable();
1403 
1404 	do {
1405 		__init_discard_policy(sbi, &dpolicy, DPOLICY_BG,
1406 					dcc->discard_granularity);
1407 
1408 		wait_event_interruptible_timeout(*q,
1409 				kthread_should_stop() || freezing(current) ||
1410 				dcc->discard_wake,
1411 				msecs_to_jiffies(wait_ms));
1412 
1413 		if (dcc->discard_wake)
1414 			dcc->discard_wake = 0;
1415 
1416 		if (try_to_freeze())
1417 			continue;
1418 		if (f2fs_readonly(sbi->sb))
1419 			continue;
1420 		if (kthread_should_stop())
1421 			return 0;
1422 		if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
1423 			wait_ms = dpolicy.max_interval;
1424 			continue;
1425 		}
1426 
1427 		if (sbi->gc_mode == GC_URGENT)
1428 			__init_discard_policy(sbi, &dpolicy, DPOLICY_FORCE, 1);
1429 
1430 		sb_start_intwrite(sbi->sb);
1431 
1432 		issued = __issue_discard_cmd(sbi, &dpolicy);
1433 		if (issued > 0) {
1434 			__wait_all_discard_cmd(sbi, &dpolicy);
1435 			wait_ms = dpolicy.min_interval;
1436 		} else if (issued == -1){
1437 			wait_ms = dpolicy.mid_interval;
1438 		} else {
1439 			wait_ms = dpolicy.max_interval;
1440 		}
1441 
1442 		sb_end_intwrite(sbi->sb);
1443 
1444 	} while (!kthread_should_stop());
1445 	return 0;
1446 }
1447 
1448 #ifdef CONFIG_BLK_DEV_ZONED
1449 static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
1450 		struct block_device *bdev, block_t blkstart, block_t blklen)
1451 {
1452 	sector_t sector, nr_sects;
1453 	block_t lblkstart = blkstart;
1454 	int devi = 0;
1455 
1456 	if (sbi->s_ndevs) {
1457 		devi = f2fs_target_device_index(sbi, blkstart);
1458 		blkstart -= FDEV(devi).start_blk;
1459 	}
1460 
1461 	/*
1462 	 * We need to know the type of the zone: for conventional zones,
1463 	 * use regular discard if the drive supports it. For sequential
1464 	 * zones, reset the zone write pointer.
1465 	 */
1466 	switch (get_blkz_type(sbi, bdev, blkstart)) {
1467 
1468 	case BLK_ZONE_TYPE_CONVENTIONAL:
1469 		if (!blk_queue_discard(bdev_get_queue(bdev)))
1470 			return 0;
1471 		return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
1472 	case BLK_ZONE_TYPE_SEQWRITE_REQ:
1473 	case BLK_ZONE_TYPE_SEQWRITE_PREF:
1474 		sector = SECTOR_FROM_BLOCK(blkstart);
1475 		nr_sects = SECTOR_FROM_BLOCK(blklen);
1476 
1477 		if (sector & (bdev_zone_sectors(bdev) - 1) ||
1478 				nr_sects != bdev_zone_sectors(bdev)) {
1479 			f2fs_msg(sbi->sb, KERN_INFO,
1480 				"(%d) %s: Unaligned discard attempted (block %x + %x)",
1481 				devi, sbi->s_ndevs ? FDEV(devi).path: "",
1482 				blkstart, blklen);
1483 			return -EIO;
1484 		}
1485 		trace_f2fs_issue_reset_zone(bdev, blkstart);
1486 		return blkdev_reset_zones(bdev, sector,
1487 					  nr_sects, GFP_NOFS);
1488 	default:
1489 		/* Unknown zone type: broken device ? */
1490 		return -EIO;
1491 	}
1492 }
1493 #endif
1494 
1495 static int __issue_discard_async(struct f2fs_sb_info *sbi,
1496 		struct block_device *bdev, block_t blkstart, block_t blklen)
1497 {
1498 #ifdef CONFIG_BLK_DEV_ZONED
1499 	if (f2fs_sb_has_blkzoned(sbi->sb) &&
1500 				bdev_zoned_model(bdev) != BLK_ZONED_NONE)
1501 		return __f2fs_issue_discard_zone(sbi, bdev, blkstart, blklen);
1502 #endif
1503 	return __queue_discard_cmd(sbi, bdev, blkstart, blklen);
1504 }
1505 
1506 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
1507 				block_t blkstart, block_t blklen)
1508 {
1509 	sector_t start = blkstart, len = 0;
1510 	struct block_device *bdev;
1511 	struct seg_entry *se;
1512 	unsigned int offset;
1513 	block_t i;
1514 	int err = 0;
1515 
1516 	bdev = f2fs_target_device(sbi, blkstart, NULL);
1517 
1518 	for (i = blkstart; i < blkstart + blklen; i++, len++) {
1519 		if (i != start) {
1520 			struct block_device *bdev2 =
1521 				f2fs_target_device(sbi, i, NULL);
1522 
1523 			if (bdev2 != bdev) {
1524 				err = __issue_discard_async(sbi, bdev,
1525 						start, len);
1526 				if (err)
1527 					return err;
1528 				bdev = bdev2;
1529 				start = i;
1530 				len = 0;
1531 			}
1532 		}
1533 
1534 		se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
1535 		offset = GET_BLKOFF_FROM_SEG0(sbi, i);
1536 
1537 		if (!f2fs_test_and_set_bit(offset, se->discard_map))
1538 			sbi->discard_blks--;
1539 	}
1540 
1541 	if (len)
1542 		err = __issue_discard_async(sbi, bdev, start, len);
1543 	return err;
1544 }
1545 
1546 static bool add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc,
1547 							bool check_only)
1548 {
1549 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
1550 	int max_blocks = sbi->blocks_per_seg;
1551 	struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
1552 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
1553 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
1554 	unsigned long *discard_map = (unsigned long *)se->discard_map;
1555 	unsigned long *dmap = SIT_I(sbi)->tmp_map;
1556 	unsigned int start = 0, end = -1;
1557 	bool force = (cpc->reason & CP_DISCARD);
1558 	struct discard_entry *de = NULL;
1559 	struct list_head *head = &SM_I(sbi)->dcc_info->entry_list;
1560 	int i;
1561 
1562 	if (se->valid_blocks == max_blocks || !f2fs_discard_en(sbi))
1563 		return false;
1564 
1565 	if (!force) {
1566 		if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
1567 			SM_I(sbi)->dcc_info->nr_discards >=
1568 				SM_I(sbi)->dcc_info->max_discards)
1569 			return false;
1570 	}
1571 
1572 	/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
1573 	for (i = 0; i < entries; i++)
1574 		dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
1575 				(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
1576 
1577 	while (force || SM_I(sbi)->dcc_info->nr_discards <=
1578 				SM_I(sbi)->dcc_info->max_discards) {
1579 		start = __find_rev_next_bit(dmap, max_blocks, end + 1);
1580 		if (start >= max_blocks)
1581 			break;
1582 
1583 		end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
1584 		if (force && start && end != max_blocks
1585 					&& (end - start) < cpc->trim_minlen)
1586 			continue;
1587 
1588 		if (check_only)
1589 			return true;
1590 
1591 		if (!de) {
1592 			de = f2fs_kmem_cache_alloc(discard_entry_slab,
1593 								GFP_F2FS_ZERO);
1594 			de->start_blkaddr = START_BLOCK(sbi, cpc->trim_start);
1595 			list_add_tail(&de->list, head);
1596 		}
1597 
1598 		for (i = start; i < end; i++)
1599 			__set_bit_le(i, (void *)de->discard_map);
1600 
1601 		SM_I(sbi)->dcc_info->nr_discards += end - start;
1602 	}
1603 	return false;
1604 }
1605 
1606 static void release_discard_addr(struct discard_entry *entry)
1607 {
1608 	list_del(&entry->list);
1609 	kmem_cache_free(discard_entry_slab, entry);
1610 }
1611 
1612 void f2fs_release_discard_addrs(struct f2fs_sb_info *sbi)
1613 {
1614 	struct list_head *head = &(SM_I(sbi)->dcc_info->entry_list);
1615 	struct discard_entry *entry, *this;
1616 
1617 	/* drop caches */
1618 	list_for_each_entry_safe(entry, this, head, list)
1619 		release_discard_addr(entry);
1620 }
1621 
1622 /*
1623  * Should call f2fs_clear_prefree_segments after checkpoint is done.
1624  */
1625 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
1626 {
1627 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1628 	unsigned int segno;
1629 
1630 	mutex_lock(&dirty_i->seglist_lock);
1631 	for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
1632 		__set_test_and_free(sbi, segno);
1633 	mutex_unlock(&dirty_i->seglist_lock);
1634 }
1635 
1636 void f2fs_clear_prefree_segments(struct f2fs_sb_info *sbi,
1637 						struct cp_control *cpc)
1638 {
1639 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1640 	struct list_head *head = &dcc->entry_list;
1641 	struct discard_entry *entry, *this;
1642 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1643 	unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
1644 	unsigned int start = 0, end = -1;
1645 	unsigned int secno, start_segno;
1646 	bool force = (cpc->reason & CP_DISCARD);
1647 
1648 	mutex_lock(&dirty_i->seglist_lock);
1649 
1650 	while (1) {
1651 		int i;
1652 		start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
1653 		if (start >= MAIN_SEGS(sbi))
1654 			break;
1655 		end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
1656 								start + 1);
1657 
1658 		for (i = start; i < end; i++)
1659 			clear_bit(i, prefree_map);
1660 
1661 		dirty_i->nr_dirty[PRE] -= end - start;
1662 
1663 		if (!test_opt(sbi, DISCARD))
1664 			continue;
1665 
1666 		if (force && start >= cpc->trim_start &&
1667 					(end - 1) <= cpc->trim_end)
1668 				continue;
1669 
1670 		if (!test_opt(sbi, LFS) || sbi->segs_per_sec == 1) {
1671 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
1672 				(end - start) << sbi->log_blocks_per_seg);
1673 			continue;
1674 		}
1675 next:
1676 		secno = GET_SEC_FROM_SEG(sbi, start);
1677 		start_segno = GET_SEG_FROM_SEC(sbi, secno);
1678 		if (!IS_CURSEC(sbi, secno) &&
1679 			!get_valid_blocks(sbi, start, true))
1680 			f2fs_issue_discard(sbi, START_BLOCK(sbi, start_segno),
1681 				sbi->segs_per_sec << sbi->log_blocks_per_seg);
1682 
1683 		start = start_segno + sbi->segs_per_sec;
1684 		if (start < end)
1685 			goto next;
1686 		else
1687 			end = start - 1;
1688 	}
1689 	mutex_unlock(&dirty_i->seglist_lock);
1690 
1691 	/* send small discards */
1692 	list_for_each_entry_safe(entry, this, head, list) {
1693 		unsigned int cur_pos = 0, next_pos, len, total_len = 0;
1694 		bool is_valid = test_bit_le(0, entry->discard_map);
1695 
1696 find_next:
1697 		if (is_valid) {
1698 			next_pos = find_next_zero_bit_le(entry->discard_map,
1699 					sbi->blocks_per_seg, cur_pos);
1700 			len = next_pos - cur_pos;
1701 
1702 			if (f2fs_sb_has_blkzoned(sbi->sb) ||
1703 			    (force && len < cpc->trim_minlen))
1704 				goto skip;
1705 
1706 			f2fs_issue_discard(sbi, entry->start_blkaddr + cur_pos,
1707 									len);
1708 			total_len += len;
1709 		} else {
1710 			next_pos = find_next_bit_le(entry->discard_map,
1711 					sbi->blocks_per_seg, cur_pos);
1712 		}
1713 skip:
1714 		cur_pos = next_pos;
1715 		is_valid = !is_valid;
1716 
1717 		if (cur_pos < sbi->blocks_per_seg)
1718 			goto find_next;
1719 
1720 		release_discard_addr(entry);
1721 		dcc->nr_discards -= total_len;
1722 	}
1723 
1724 	wake_up_discard_thread(sbi, false);
1725 }
1726 
1727 static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
1728 {
1729 	dev_t dev = sbi->sb->s_bdev->bd_dev;
1730 	struct discard_cmd_control *dcc;
1731 	int err = 0, i;
1732 
1733 	if (SM_I(sbi)->dcc_info) {
1734 		dcc = SM_I(sbi)->dcc_info;
1735 		goto init_thread;
1736 	}
1737 
1738 	dcc = f2fs_kzalloc(sbi, sizeof(struct discard_cmd_control), GFP_KERNEL);
1739 	if (!dcc)
1740 		return -ENOMEM;
1741 
1742 	dcc->discard_granularity = DEFAULT_DISCARD_GRANULARITY;
1743 	INIT_LIST_HEAD(&dcc->entry_list);
1744 	for (i = 0; i < MAX_PLIST_NUM; i++)
1745 		INIT_LIST_HEAD(&dcc->pend_list[i]);
1746 	INIT_LIST_HEAD(&dcc->wait_list);
1747 	INIT_LIST_HEAD(&dcc->fstrim_list);
1748 	mutex_init(&dcc->cmd_lock);
1749 	atomic_set(&dcc->issued_discard, 0);
1750 	atomic_set(&dcc->issing_discard, 0);
1751 	atomic_set(&dcc->discard_cmd_cnt, 0);
1752 	dcc->nr_discards = 0;
1753 	dcc->max_discards = MAIN_SEGS(sbi) << sbi->log_blocks_per_seg;
1754 	dcc->undiscard_blks = 0;
1755 	dcc->root = RB_ROOT;
1756 	dcc->rbtree_check = false;
1757 
1758 	init_waitqueue_head(&dcc->discard_wait_queue);
1759 	SM_I(sbi)->dcc_info = dcc;
1760 init_thread:
1761 	dcc->f2fs_issue_discard = kthread_run(issue_discard_thread, sbi,
1762 				"f2fs_discard-%u:%u", MAJOR(dev), MINOR(dev));
1763 	if (IS_ERR(dcc->f2fs_issue_discard)) {
1764 		err = PTR_ERR(dcc->f2fs_issue_discard);
1765 		kfree(dcc);
1766 		SM_I(sbi)->dcc_info = NULL;
1767 		return err;
1768 	}
1769 
1770 	return err;
1771 }
1772 
1773 static void destroy_discard_cmd_control(struct f2fs_sb_info *sbi)
1774 {
1775 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
1776 
1777 	if (!dcc)
1778 		return;
1779 
1780 	f2fs_stop_discard_thread(sbi);
1781 
1782 	kfree(dcc);
1783 	SM_I(sbi)->dcc_info = NULL;
1784 }
1785 
1786 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
1787 {
1788 	struct sit_info *sit_i = SIT_I(sbi);
1789 
1790 	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
1791 		sit_i->dirty_sentries++;
1792 		return false;
1793 	}
1794 
1795 	return true;
1796 }
1797 
1798 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
1799 					unsigned int segno, int modified)
1800 {
1801 	struct seg_entry *se = get_seg_entry(sbi, segno);
1802 	se->type = type;
1803 	if (modified)
1804 		__mark_sit_entry_dirty(sbi, segno);
1805 }
1806 
1807 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
1808 {
1809 	struct seg_entry *se;
1810 	unsigned int segno, offset;
1811 	long int new_vblocks;
1812 	bool exist;
1813 #ifdef CONFIG_F2FS_CHECK_FS
1814 	bool mir_exist;
1815 #endif
1816 
1817 	segno = GET_SEGNO(sbi, blkaddr);
1818 
1819 	se = get_seg_entry(sbi, segno);
1820 	new_vblocks = se->valid_blocks + del;
1821 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1822 
1823 	f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
1824 				(new_vblocks > sbi->blocks_per_seg)));
1825 
1826 	se->valid_blocks = new_vblocks;
1827 	se->mtime = get_mtime(sbi, false);
1828 	if (se->mtime > SIT_I(sbi)->max_mtime)
1829 		SIT_I(sbi)->max_mtime = se->mtime;
1830 
1831 	/* Update valid block bitmap */
1832 	if (del > 0) {
1833 		exist = f2fs_test_and_set_bit(offset, se->cur_valid_map);
1834 #ifdef CONFIG_F2FS_CHECK_FS
1835 		mir_exist = f2fs_test_and_set_bit(offset,
1836 						se->cur_valid_map_mir);
1837 		if (unlikely(exist != mir_exist)) {
1838 			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
1839 				"when setting bitmap, blk:%u, old bit:%d",
1840 				blkaddr, exist);
1841 			f2fs_bug_on(sbi, 1);
1842 		}
1843 #endif
1844 		if (unlikely(exist)) {
1845 			f2fs_msg(sbi->sb, KERN_ERR,
1846 				"Bitmap was wrongly set, blk:%u", blkaddr);
1847 			f2fs_bug_on(sbi, 1);
1848 			se->valid_blocks--;
1849 			del = 0;
1850 		}
1851 
1852 		if (f2fs_discard_en(sbi) &&
1853 			!f2fs_test_and_set_bit(offset, se->discard_map))
1854 			sbi->discard_blks--;
1855 
1856 		/* don't overwrite by SSR to keep node chain */
1857 		if (IS_NODESEG(se->type)) {
1858 			if (!f2fs_test_and_set_bit(offset, se->ckpt_valid_map))
1859 				se->ckpt_valid_blocks++;
1860 		}
1861 	} else {
1862 		exist = f2fs_test_and_clear_bit(offset, se->cur_valid_map);
1863 #ifdef CONFIG_F2FS_CHECK_FS
1864 		mir_exist = f2fs_test_and_clear_bit(offset,
1865 						se->cur_valid_map_mir);
1866 		if (unlikely(exist != mir_exist)) {
1867 			f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
1868 				"when clearing bitmap, blk:%u, old bit:%d",
1869 				blkaddr, exist);
1870 			f2fs_bug_on(sbi, 1);
1871 		}
1872 #endif
1873 		if (unlikely(!exist)) {
1874 			f2fs_msg(sbi->sb, KERN_ERR,
1875 				"Bitmap was wrongly cleared, blk:%u", blkaddr);
1876 			f2fs_bug_on(sbi, 1);
1877 			se->valid_blocks++;
1878 			del = 0;
1879 		}
1880 
1881 		if (f2fs_discard_en(sbi) &&
1882 			f2fs_test_and_clear_bit(offset, se->discard_map))
1883 			sbi->discard_blks++;
1884 	}
1885 	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
1886 		se->ckpt_valid_blocks += del;
1887 
1888 	__mark_sit_entry_dirty(sbi, segno);
1889 
1890 	/* update total number of valid blocks to be written in ckpt area */
1891 	SIT_I(sbi)->written_valid_blocks += del;
1892 
1893 	if (sbi->segs_per_sec > 1)
1894 		get_sec_entry(sbi, segno)->valid_blocks += del;
1895 }
1896 
1897 void f2fs_invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
1898 {
1899 	unsigned int segno = GET_SEGNO(sbi, addr);
1900 	struct sit_info *sit_i = SIT_I(sbi);
1901 
1902 	f2fs_bug_on(sbi, addr == NULL_ADDR);
1903 	if (addr == NEW_ADDR)
1904 		return;
1905 
1906 	/* add it into sit main buffer */
1907 	down_write(&sit_i->sentry_lock);
1908 
1909 	update_sit_entry(sbi, addr, -1);
1910 
1911 	/* add it into dirty seglist */
1912 	locate_dirty_segment(sbi, segno);
1913 
1914 	up_write(&sit_i->sentry_lock);
1915 }
1916 
1917 bool f2fs_is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
1918 {
1919 	struct sit_info *sit_i = SIT_I(sbi);
1920 	unsigned int segno, offset;
1921 	struct seg_entry *se;
1922 	bool is_cp = false;
1923 
1924 	if (!is_valid_data_blkaddr(sbi, blkaddr))
1925 		return true;
1926 
1927 	down_read(&sit_i->sentry_lock);
1928 
1929 	segno = GET_SEGNO(sbi, blkaddr);
1930 	se = get_seg_entry(sbi, segno);
1931 	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
1932 
1933 	if (f2fs_test_bit(offset, se->ckpt_valid_map))
1934 		is_cp = true;
1935 
1936 	up_read(&sit_i->sentry_lock);
1937 
1938 	return is_cp;
1939 }
1940 
1941 /*
1942  * This function should be resided under the curseg_mutex lock
1943  */
1944 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
1945 					struct f2fs_summary *sum)
1946 {
1947 	struct curseg_info *curseg = CURSEG_I(sbi, type);
1948 	void *addr = curseg->sum_blk;
1949 	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
1950 	memcpy(addr, sum, sizeof(struct f2fs_summary));
1951 }
1952 
1953 /*
1954  * Calculate the number of current summary pages for writing
1955  */
1956 int f2fs_npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
1957 {
1958 	int valid_sum_count = 0;
1959 	int i, sum_in_page;
1960 
1961 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1962 		if (sbi->ckpt->alloc_type[i] == SSR)
1963 			valid_sum_count += sbi->blocks_per_seg;
1964 		else {
1965 			if (for_ra)
1966 				valid_sum_count += le16_to_cpu(
1967 					F2FS_CKPT(sbi)->cur_data_blkoff[i]);
1968 			else
1969 				valid_sum_count += curseg_blkoff(sbi, i);
1970 		}
1971 	}
1972 
1973 	sum_in_page = (PAGE_SIZE - 2 * SUM_JOURNAL_SIZE -
1974 			SUM_FOOTER_SIZE) / SUMMARY_SIZE;
1975 	if (valid_sum_count <= sum_in_page)
1976 		return 1;
1977 	else if ((valid_sum_count - sum_in_page) <=
1978 		(PAGE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
1979 		return 2;
1980 	return 3;
1981 }
1982 
1983 /*
1984  * Caller should put this summary page
1985  */
1986 struct page *f2fs_get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
1987 {
1988 	return f2fs_get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
1989 }
1990 
1991 void f2fs_update_meta_page(struct f2fs_sb_info *sbi,
1992 					void *src, block_t blk_addr)
1993 {
1994 	struct page *page = f2fs_grab_meta_page(sbi, blk_addr);
1995 
1996 	memcpy(page_address(page), src, PAGE_SIZE);
1997 	set_page_dirty(page);
1998 	f2fs_put_page(page, 1);
1999 }
2000 
2001 static void write_sum_page(struct f2fs_sb_info *sbi,
2002 			struct f2fs_summary_block *sum_blk, block_t blk_addr)
2003 {
2004 	f2fs_update_meta_page(sbi, (void *)sum_blk, blk_addr);
2005 }
2006 
2007 static void write_current_sum_page(struct f2fs_sb_info *sbi,
2008 						int type, block_t blk_addr)
2009 {
2010 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2011 	struct page *page = f2fs_grab_meta_page(sbi, blk_addr);
2012 	struct f2fs_summary_block *src = curseg->sum_blk;
2013 	struct f2fs_summary_block *dst;
2014 
2015 	dst = (struct f2fs_summary_block *)page_address(page);
2016 	memset(dst, 0, PAGE_SIZE);
2017 
2018 	mutex_lock(&curseg->curseg_mutex);
2019 
2020 	down_read(&curseg->journal_rwsem);
2021 	memcpy(&dst->journal, curseg->journal, SUM_JOURNAL_SIZE);
2022 	up_read(&curseg->journal_rwsem);
2023 
2024 	memcpy(dst->entries, src->entries, SUM_ENTRY_SIZE);
2025 	memcpy(&dst->footer, &src->footer, SUM_FOOTER_SIZE);
2026 
2027 	mutex_unlock(&curseg->curseg_mutex);
2028 
2029 	set_page_dirty(page);
2030 	f2fs_put_page(page, 1);
2031 }
2032 
2033 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
2034 {
2035 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2036 	unsigned int segno = curseg->segno + 1;
2037 	struct free_segmap_info *free_i = FREE_I(sbi);
2038 
2039 	if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
2040 		return !test_bit(segno, free_i->free_segmap);
2041 	return 0;
2042 }
2043 
2044 /*
2045  * Find a new segment from the free segments bitmap to right order
2046  * This function should be returned with success, otherwise BUG
2047  */
2048 static void get_new_segment(struct f2fs_sb_info *sbi,
2049 			unsigned int *newseg, bool new_sec, int dir)
2050 {
2051 	struct free_segmap_info *free_i = FREE_I(sbi);
2052 	unsigned int segno, secno, zoneno;
2053 	unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
2054 	unsigned int hint = GET_SEC_FROM_SEG(sbi, *newseg);
2055 	unsigned int old_zoneno = GET_ZONE_FROM_SEG(sbi, *newseg);
2056 	unsigned int left_start = hint;
2057 	bool init = true;
2058 	int go_left = 0;
2059 	int i;
2060 
2061 	spin_lock(&free_i->segmap_lock);
2062 
2063 	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
2064 		segno = find_next_zero_bit(free_i->free_segmap,
2065 			GET_SEG_FROM_SEC(sbi, hint + 1), *newseg + 1);
2066 		if (segno < GET_SEG_FROM_SEC(sbi, hint + 1))
2067 			goto got_it;
2068 	}
2069 find_other_zone:
2070 	secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
2071 	if (secno >= MAIN_SECS(sbi)) {
2072 		if (dir == ALLOC_RIGHT) {
2073 			secno = find_next_zero_bit(free_i->free_secmap,
2074 							MAIN_SECS(sbi), 0);
2075 			f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
2076 		} else {
2077 			go_left = 1;
2078 			left_start = hint - 1;
2079 		}
2080 	}
2081 	if (go_left == 0)
2082 		goto skip_left;
2083 
2084 	while (test_bit(left_start, free_i->free_secmap)) {
2085 		if (left_start > 0) {
2086 			left_start--;
2087 			continue;
2088 		}
2089 		left_start = find_next_zero_bit(free_i->free_secmap,
2090 							MAIN_SECS(sbi), 0);
2091 		f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
2092 		break;
2093 	}
2094 	secno = left_start;
2095 skip_left:
2096 	segno = GET_SEG_FROM_SEC(sbi, secno);
2097 	zoneno = GET_ZONE_FROM_SEC(sbi, secno);
2098 
2099 	/* give up on finding another zone */
2100 	if (!init)
2101 		goto got_it;
2102 	if (sbi->secs_per_zone == 1)
2103 		goto got_it;
2104 	if (zoneno == old_zoneno)
2105 		goto got_it;
2106 	if (dir == ALLOC_LEFT) {
2107 		if (!go_left && zoneno + 1 >= total_zones)
2108 			goto got_it;
2109 		if (go_left && zoneno == 0)
2110 			goto got_it;
2111 	}
2112 	for (i = 0; i < NR_CURSEG_TYPE; i++)
2113 		if (CURSEG_I(sbi, i)->zone == zoneno)
2114 			break;
2115 
2116 	if (i < NR_CURSEG_TYPE) {
2117 		/* zone is in user, try another */
2118 		if (go_left)
2119 			hint = zoneno * sbi->secs_per_zone - 1;
2120 		else if (zoneno + 1 >= total_zones)
2121 			hint = 0;
2122 		else
2123 			hint = (zoneno + 1) * sbi->secs_per_zone;
2124 		init = false;
2125 		goto find_other_zone;
2126 	}
2127 got_it:
2128 	/* set it as dirty segment in free segmap */
2129 	f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
2130 	__set_inuse(sbi, segno);
2131 	*newseg = segno;
2132 	spin_unlock(&free_i->segmap_lock);
2133 }
2134 
2135 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
2136 {
2137 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2138 	struct summary_footer *sum_footer;
2139 
2140 	curseg->segno = curseg->next_segno;
2141 	curseg->zone = GET_ZONE_FROM_SEG(sbi, curseg->segno);
2142 	curseg->next_blkoff = 0;
2143 	curseg->next_segno = NULL_SEGNO;
2144 
2145 	sum_footer = &(curseg->sum_blk->footer);
2146 	memset(sum_footer, 0, sizeof(struct summary_footer));
2147 	if (IS_DATASEG(type))
2148 		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
2149 	if (IS_NODESEG(type))
2150 		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
2151 	__set_sit_entry_type(sbi, type, curseg->segno, modified);
2152 }
2153 
2154 static unsigned int __get_next_segno(struct f2fs_sb_info *sbi, int type)
2155 {
2156 	/* if segs_per_sec is large than 1, we need to keep original policy. */
2157 	if (sbi->segs_per_sec != 1)
2158 		return CURSEG_I(sbi, type)->segno;
2159 
2160 	if (test_opt(sbi, NOHEAP) &&
2161 		(type == CURSEG_HOT_DATA || IS_NODESEG(type)))
2162 		return 0;
2163 
2164 	if (SIT_I(sbi)->last_victim[ALLOC_NEXT])
2165 		return SIT_I(sbi)->last_victim[ALLOC_NEXT];
2166 
2167 	/* find segments from 0 to reuse freed segments */
2168 	if (F2FS_OPTION(sbi).alloc_mode == ALLOC_MODE_REUSE)
2169 		return 0;
2170 
2171 	return CURSEG_I(sbi, type)->segno;
2172 }
2173 
2174 /*
2175  * Allocate a current working segment.
2176  * This function always allocates a free segment in LFS manner.
2177  */
2178 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
2179 {
2180 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2181 	unsigned int segno = curseg->segno;
2182 	int dir = ALLOC_LEFT;
2183 
2184 	write_sum_page(sbi, curseg->sum_blk,
2185 				GET_SUM_BLOCK(sbi, segno));
2186 	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
2187 		dir = ALLOC_RIGHT;
2188 
2189 	if (test_opt(sbi, NOHEAP))
2190 		dir = ALLOC_RIGHT;
2191 
2192 	segno = __get_next_segno(sbi, type);
2193 	get_new_segment(sbi, &segno, new_sec, dir);
2194 	curseg->next_segno = segno;
2195 	reset_curseg(sbi, type, 1);
2196 	curseg->alloc_type = LFS;
2197 }
2198 
2199 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
2200 			struct curseg_info *seg, block_t start)
2201 {
2202 	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
2203 	int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
2204 	unsigned long *target_map = SIT_I(sbi)->tmp_map;
2205 	unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
2206 	unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
2207 	int i, pos;
2208 
2209 	for (i = 0; i < entries; i++)
2210 		target_map[i] = ckpt_map[i] | cur_map[i];
2211 
2212 	pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
2213 
2214 	seg->next_blkoff = pos;
2215 }
2216 
2217 /*
2218  * If a segment is written by LFS manner, next block offset is just obtained
2219  * by increasing the current block offset. However, if a segment is written by
2220  * SSR manner, next block offset obtained by calling __next_free_blkoff
2221  */
2222 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
2223 				struct curseg_info *seg)
2224 {
2225 	if (seg->alloc_type == SSR)
2226 		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
2227 	else
2228 		seg->next_blkoff++;
2229 }
2230 
2231 /*
2232  * This function always allocates a used segment(from dirty seglist) by SSR
2233  * manner, so it should recover the existing segment information of valid blocks
2234  */
2235 static void change_curseg(struct f2fs_sb_info *sbi, int type)
2236 {
2237 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2238 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2239 	unsigned int new_segno = curseg->next_segno;
2240 	struct f2fs_summary_block *sum_node;
2241 	struct page *sum_page;
2242 
2243 	write_sum_page(sbi, curseg->sum_blk,
2244 				GET_SUM_BLOCK(sbi, curseg->segno));
2245 	__set_test_and_inuse(sbi, new_segno);
2246 
2247 	mutex_lock(&dirty_i->seglist_lock);
2248 	__remove_dirty_segment(sbi, new_segno, PRE);
2249 	__remove_dirty_segment(sbi, new_segno, DIRTY);
2250 	mutex_unlock(&dirty_i->seglist_lock);
2251 
2252 	reset_curseg(sbi, type, 1);
2253 	curseg->alloc_type = SSR;
2254 	__next_free_blkoff(sbi, curseg, 0);
2255 
2256 	sum_page = f2fs_get_sum_page(sbi, new_segno);
2257 	sum_node = (struct f2fs_summary_block *)page_address(sum_page);
2258 	memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
2259 	f2fs_put_page(sum_page, 1);
2260 }
2261 
2262 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
2263 {
2264 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2265 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
2266 	unsigned segno = NULL_SEGNO;
2267 	int i, cnt;
2268 	bool reversed = false;
2269 
2270 	/* f2fs_need_SSR() already forces to do this */
2271 	if (v_ops->get_victim(sbi, &segno, BG_GC, type, SSR)) {
2272 		curseg->next_segno = segno;
2273 		return 1;
2274 	}
2275 
2276 	/* For node segments, let's do SSR more intensively */
2277 	if (IS_NODESEG(type)) {
2278 		if (type >= CURSEG_WARM_NODE) {
2279 			reversed = true;
2280 			i = CURSEG_COLD_NODE;
2281 		} else {
2282 			i = CURSEG_HOT_NODE;
2283 		}
2284 		cnt = NR_CURSEG_NODE_TYPE;
2285 	} else {
2286 		if (type >= CURSEG_WARM_DATA) {
2287 			reversed = true;
2288 			i = CURSEG_COLD_DATA;
2289 		} else {
2290 			i = CURSEG_HOT_DATA;
2291 		}
2292 		cnt = NR_CURSEG_DATA_TYPE;
2293 	}
2294 
2295 	for (; cnt-- > 0; reversed ? i-- : i++) {
2296 		if (i == type)
2297 			continue;
2298 		if (v_ops->get_victim(sbi, &segno, BG_GC, i, SSR)) {
2299 			curseg->next_segno = segno;
2300 			return 1;
2301 		}
2302 	}
2303 	return 0;
2304 }
2305 
2306 /*
2307  * flush out current segment and replace it with new segment
2308  * This function should be returned with success, otherwise BUG
2309  */
2310 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
2311 						int type, bool force)
2312 {
2313 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2314 
2315 	if (force)
2316 		new_curseg(sbi, type, true);
2317 	else if (!is_set_ckpt_flags(sbi, CP_CRC_RECOVERY_FLAG) &&
2318 					type == CURSEG_WARM_NODE)
2319 		new_curseg(sbi, type, false);
2320 	else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
2321 		new_curseg(sbi, type, false);
2322 	else if (f2fs_need_SSR(sbi) && get_ssr_segment(sbi, type))
2323 		change_curseg(sbi, type);
2324 	else
2325 		new_curseg(sbi, type, false);
2326 
2327 	stat_inc_seg_type(sbi, curseg);
2328 }
2329 
2330 void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi)
2331 {
2332 	struct curseg_info *curseg;
2333 	unsigned int old_segno;
2334 	int i;
2335 
2336 	down_write(&SIT_I(sbi)->sentry_lock);
2337 
2338 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
2339 		curseg = CURSEG_I(sbi, i);
2340 		old_segno = curseg->segno;
2341 		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
2342 		locate_dirty_segment(sbi, old_segno);
2343 	}
2344 
2345 	up_write(&SIT_I(sbi)->sentry_lock);
2346 }
2347 
2348 static const struct segment_allocation default_salloc_ops = {
2349 	.allocate_segment = allocate_segment_by_default,
2350 };
2351 
2352 bool f2fs_exist_trim_candidates(struct f2fs_sb_info *sbi,
2353 						struct cp_control *cpc)
2354 {
2355 	__u64 trim_start = cpc->trim_start;
2356 	bool has_candidate = false;
2357 
2358 	down_write(&SIT_I(sbi)->sentry_lock);
2359 	for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++) {
2360 		if (add_discard_addrs(sbi, cpc, true)) {
2361 			has_candidate = true;
2362 			break;
2363 		}
2364 	}
2365 	up_write(&SIT_I(sbi)->sentry_lock);
2366 
2367 	cpc->trim_start = trim_start;
2368 	return has_candidate;
2369 }
2370 
2371 static void __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
2372 					struct discard_policy *dpolicy,
2373 					unsigned int start, unsigned int end)
2374 {
2375 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
2376 	struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
2377 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
2378 	struct discard_cmd *dc;
2379 	struct blk_plug plug;
2380 	int issued;
2381 
2382 next:
2383 	issued = 0;
2384 
2385 	mutex_lock(&dcc->cmd_lock);
2386 	if (unlikely(dcc->rbtree_check))
2387 		f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
2388 								&dcc->root));
2389 
2390 	dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
2391 					NULL, start,
2392 					(struct rb_entry **)&prev_dc,
2393 					(struct rb_entry **)&next_dc,
2394 					&insert_p, &insert_parent, true);
2395 	if (!dc)
2396 		dc = next_dc;
2397 
2398 	blk_start_plug(&plug);
2399 
2400 	while (dc && dc->lstart <= end) {
2401 		struct rb_node *node;
2402 
2403 		if (dc->len < dpolicy->granularity)
2404 			goto skip;
2405 
2406 		if (dc->state != D_PREP) {
2407 			list_move_tail(&dc->list, &dcc->fstrim_list);
2408 			goto skip;
2409 		}
2410 
2411 		__submit_discard_cmd(sbi, dpolicy, dc);
2412 
2413 		if (++issued >= dpolicy->max_requests) {
2414 			start = dc->lstart + dc->len;
2415 
2416 			blk_finish_plug(&plug);
2417 			mutex_unlock(&dcc->cmd_lock);
2418 			__wait_all_discard_cmd(sbi, NULL);
2419 			congestion_wait(BLK_RW_ASYNC, HZ/50);
2420 			goto next;
2421 		}
2422 skip:
2423 		node = rb_next(&dc->rb_node);
2424 		dc = rb_entry_safe(node, struct discard_cmd, rb_node);
2425 
2426 		if (fatal_signal_pending(current))
2427 			break;
2428 	}
2429 
2430 	blk_finish_plug(&plug);
2431 	mutex_unlock(&dcc->cmd_lock);
2432 }
2433 
2434 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
2435 {
2436 	__u64 start = F2FS_BYTES_TO_BLK(range->start);
2437 	__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
2438 	unsigned int start_segno, end_segno;
2439 	block_t start_block, end_block;
2440 	struct cp_control cpc;
2441 	struct discard_policy dpolicy;
2442 	unsigned long long trimmed = 0;
2443 	int err = 0;
2444 
2445 	if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
2446 		return -EINVAL;
2447 
2448 	if (end <= MAIN_BLKADDR(sbi))
2449 		return -EINVAL;
2450 
2451 	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) {
2452 		f2fs_msg(sbi->sb, KERN_WARNING,
2453 			"Found FS corruption, run fsck to fix.");
2454 		return -EIO;
2455 	}
2456 
2457 	/* start/end segment number in main_area */
2458 	start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
2459 	end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
2460 						GET_SEGNO(sbi, end);
2461 
2462 	cpc.reason = CP_DISCARD;
2463 	cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
2464 	cpc.trim_start = start_segno;
2465 	cpc.trim_end = end_segno;
2466 
2467 	if (sbi->discard_blks == 0)
2468 		goto out;
2469 
2470 	mutex_lock(&sbi->gc_mutex);
2471 	err = f2fs_write_checkpoint(sbi, &cpc);
2472 	mutex_unlock(&sbi->gc_mutex);
2473 	if (err)
2474 		goto out;
2475 
2476 	/*
2477 	 * We filed discard candidates, but actually we don't need to wait for
2478 	 * all of them, since they'll be issued in idle time along with runtime
2479 	 * discard option. User configuration looks like using runtime discard
2480 	 * or periodic fstrim instead of it.
2481 	 */
2482 	if (test_opt(sbi, DISCARD))
2483 		goto out;
2484 
2485 	start_block = START_BLOCK(sbi, start_segno);
2486 	end_block = START_BLOCK(sbi, end_segno + 1);
2487 
2488 	__init_discard_policy(sbi, &dpolicy, DPOLICY_FSTRIM, cpc.trim_minlen);
2489 	__issue_discard_cmd_range(sbi, &dpolicy, start_block, end_block);
2490 
2491 	trimmed = __wait_discard_cmd_range(sbi, &dpolicy,
2492 					start_block, end_block);
2493 	range->len = F2FS_BLK_TO_BYTES(trimmed);
2494 out:
2495 	return err;
2496 }
2497 
2498 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
2499 {
2500 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2501 	if (curseg->next_blkoff < sbi->blocks_per_seg)
2502 		return true;
2503 	return false;
2504 }
2505 
2506 int f2fs_rw_hint_to_seg_type(enum rw_hint hint)
2507 {
2508 	switch (hint) {
2509 	case WRITE_LIFE_SHORT:
2510 		return CURSEG_HOT_DATA;
2511 	case WRITE_LIFE_EXTREME:
2512 		return CURSEG_COLD_DATA;
2513 	default:
2514 		return CURSEG_WARM_DATA;
2515 	}
2516 }
2517 
2518 /* This returns write hints for each segment type. This hints will be
2519  * passed down to block layer. There are mapping tables which depend on
2520  * the mount option 'whint_mode'.
2521  *
2522  * 1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
2523  *
2524  * 2) whint_mode=user-based. F2FS tries to pass down hints given by users.
2525  *
2526  * User                  F2FS                     Block
2527  * ----                  ----                     -----
2528  *                       META                     WRITE_LIFE_NOT_SET
2529  *                       HOT_NODE                 "
2530  *                       WARM_NODE                "
2531  *                       COLD_NODE                "
2532  * ioctl(COLD)           COLD_DATA                WRITE_LIFE_EXTREME
2533  * extension list        "                        "
2534  *
2535  * -- buffered io
2536  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2537  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2538  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2539  * WRITE_LIFE_NONE       "                        "
2540  * WRITE_LIFE_MEDIUM     "                        "
2541  * WRITE_LIFE_LONG       "                        "
2542  *
2543  * -- direct io
2544  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2545  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2546  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2547  * WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
2548  * WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
2549  * WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG
2550  *
2551  * 3) whint_mode=fs-based. F2FS passes down hints with its policy.
2552  *
2553  * User                  F2FS                     Block
2554  * ----                  ----                     -----
2555  *                       META                     WRITE_LIFE_MEDIUM;
2556  *                       HOT_NODE                 WRITE_LIFE_NOT_SET
2557  *                       WARM_NODE                "
2558  *                       COLD_NODE                WRITE_LIFE_NONE
2559  * ioctl(COLD)           COLD_DATA                WRITE_LIFE_EXTREME
2560  * extension list        "                        "
2561  *
2562  * -- buffered io
2563  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2564  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2565  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_LONG
2566  * WRITE_LIFE_NONE       "                        "
2567  * WRITE_LIFE_MEDIUM     "                        "
2568  * WRITE_LIFE_LONG       "                        "
2569  *
2570  * -- direct io
2571  * WRITE_LIFE_EXTREME    COLD_DATA                WRITE_LIFE_EXTREME
2572  * WRITE_LIFE_SHORT      HOT_DATA                 WRITE_LIFE_SHORT
2573  * WRITE_LIFE_NOT_SET    WARM_DATA                WRITE_LIFE_NOT_SET
2574  * WRITE_LIFE_NONE       "                        WRITE_LIFE_NONE
2575  * WRITE_LIFE_MEDIUM     "                        WRITE_LIFE_MEDIUM
2576  * WRITE_LIFE_LONG       "                        WRITE_LIFE_LONG
2577  */
2578 
2579 enum rw_hint f2fs_io_type_to_rw_hint(struct f2fs_sb_info *sbi,
2580 				enum page_type type, enum temp_type temp)
2581 {
2582 	if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_USER) {
2583 		if (type == DATA) {
2584 			if (temp == WARM)
2585 				return WRITE_LIFE_NOT_SET;
2586 			else if (temp == HOT)
2587 				return WRITE_LIFE_SHORT;
2588 			else if (temp == COLD)
2589 				return WRITE_LIFE_EXTREME;
2590 		} else {
2591 			return WRITE_LIFE_NOT_SET;
2592 		}
2593 	} else if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_FS) {
2594 		if (type == DATA) {
2595 			if (temp == WARM)
2596 				return WRITE_LIFE_LONG;
2597 			else if (temp == HOT)
2598 				return WRITE_LIFE_SHORT;
2599 			else if (temp == COLD)
2600 				return WRITE_LIFE_EXTREME;
2601 		} else if (type == NODE) {
2602 			if (temp == WARM || temp == HOT)
2603 				return WRITE_LIFE_NOT_SET;
2604 			else if (temp == COLD)
2605 				return WRITE_LIFE_NONE;
2606 		} else if (type == META) {
2607 			return WRITE_LIFE_MEDIUM;
2608 		}
2609 	}
2610 	return WRITE_LIFE_NOT_SET;
2611 }
2612 
2613 static int __get_segment_type_2(struct f2fs_io_info *fio)
2614 {
2615 	if (fio->type == DATA)
2616 		return CURSEG_HOT_DATA;
2617 	else
2618 		return CURSEG_HOT_NODE;
2619 }
2620 
2621 static int __get_segment_type_4(struct f2fs_io_info *fio)
2622 {
2623 	if (fio->type == DATA) {
2624 		struct inode *inode = fio->page->mapping->host;
2625 
2626 		if (S_ISDIR(inode->i_mode))
2627 			return CURSEG_HOT_DATA;
2628 		else
2629 			return CURSEG_COLD_DATA;
2630 	} else {
2631 		if (IS_DNODE(fio->page) && is_cold_node(fio->page))
2632 			return CURSEG_WARM_NODE;
2633 		else
2634 			return CURSEG_COLD_NODE;
2635 	}
2636 }
2637 
2638 static int __get_segment_type_6(struct f2fs_io_info *fio)
2639 {
2640 	if (fio->type == DATA) {
2641 		struct inode *inode = fio->page->mapping->host;
2642 
2643 		if (is_cold_data(fio->page) || file_is_cold(inode))
2644 			return CURSEG_COLD_DATA;
2645 		if (file_is_hot(inode) ||
2646 				is_inode_flag_set(inode, FI_HOT_DATA) ||
2647 				is_inode_flag_set(inode, FI_ATOMIC_FILE) ||
2648 				is_inode_flag_set(inode, FI_VOLATILE_FILE))
2649 			return CURSEG_HOT_DATA;
2650 		return f2fs_rw_hint_to_seg_type(inode->i_write_hint);
2651 	} else {
2652 		if (IS_DNODE(fio->page))
2653 			return is_cold_node(fio->page) ? CURSEG_WARM_NODE :
2654 						CURSEG_HOT_NODE;
2655 		return CURSEG_COLD_NODE;
2656 	}
2657 }
2658 
2659 static int __get_segment_type(struct f2fs_io_info *fio)
2660 {
2661 	int type = 0;
2662 
2663 	switch (F2FS_OPTION(fio->sbi).active_logs) {
2664 	case 2:
2665 		type = __get_segment_type_2(fio);
2666 		break;
2667 	case 4:
2668 		type = __get_segment_type_4(fio);
2669 		break;
2670 	case 6:
2671 		type = __get_segment_type_6(fio);
2672 		break;
2673 	default:
2674 		f2fs_bug_on(fio->sbi, true);
2675 	}
2676 
2677 	if (IS_HOT(type))
2678 		fio->temp = HOT;
2679 	else if (IS_WARM(type))
2680 		fio->temp = WARM;
2681 	else
2682 		fio->temp = COLD;
2683 	return type;
2684 }
2685 
2686 void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
2687 		block_t old_blkaddr, block_t *new_blkaddr,
2688 		struct f2fs_summary *sum, int type,
2689 		struct f2fs_io_info *fio, bool add_list)
2690 {
2691 	struct sit_info *sit_i = SIT_I(sbi);
2692 	struct curseg_info *curseg = CURSEG_I(sbi, type);
2693 
2694 	down_read(&SM_I(sbi)->curseg_lock);
2695 
2696 	mutex_lock(&curseg->curseg_mutex);
2697 	down_write(&sit_i->sentry_lock);
2698 
2699 	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
2700 
2701 	f2fs_wait_discard_bio(sbi, *new_blkaddr);
2702 
2703 	/*
2704 	 * __add_sum_entry should be resided under the curseg_mutex
2705 	 * because, this function updates a summary entry in the
2706 	 * current summary block.
2707 	 */
2708 	__add_sum_entry(sbi, type, sum);
2709 
2710 	__refresh_next_blkoff(sbi, curseg);
2711 
2712 	stat_inc_block_count(sbi, curseg);
2713 
2714 	/*
2715 	 * SIT information should be updated before segment allocation,
2716 	 * since SSR needs latest valid block information.
2717 	 */
2718 	update_sit_entry(sbi, *new_blkaddr, 1);
2719 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
2720 		update_sit_entry(sbi, old_blkaddr, -1);
2721 
2722 	if (!__has_curseg_space(sbi, type))
2723 		sit_i->s_ops->allocate_segment(sbi, type, false);
2724 
2725 	/*
2726 	 * segment dirty status should be updated after segment allocation,
2727 	 * so we just need to update status only one time after previous
2728 	 * segment being closed.
2729 	 */
2730 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
2731 	locate_dirty_segment(sbi, GET_SEGNO(sbi, *new_blkaddr));
2732 
2733 	up_write(&sit_i->sentry_lock);
2734 
2735 	if (page && IS_NODESEG(type)) {
2736 		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
2737 
2738 		f2fs_inode_chksum_set(sbi, page);
2739 	}
2740 
2741 	if (add_list) {
2742 		struct f2fs_bio_info *io;
2743 
2744 		INIT_LIST_HEAD(&fio->list);
2745 		fio->in_list = true;
2746 		fio->retry = false;
2747 		io = sbi->write_io[fio->type] + fio->temp;
2748 		spin_lock(&io->io_lock);
2749 		list_add_tail(&fio->list, &io->io_list);
2750 		spin_unlock(&io->io_lock);
2751 	}
2752 
2753 	mutex_unlock(&curseg->curseg_mutex);
2754 
2755 	up_read(&SM_I(sbi)->curseg_lock);
2756 }
2757 
2758 static void update_device_state(struct f2fs_io_info *fio)
2759 {
2760 	struct f2fs_sb_info *sbi = fio->sbi;
2761 	unsigned int devidx;
2762 
2763 	if (!sbi->s_ndevs)
2764 		return;
2765 
2766 	devidx = f2fs_target_device_index(sbi, fio->new_blkaddr);
2767 
2768 	/* update device state for fsync */
2769 	f2fs_set_dirty_device(sbi, fio->ino, devidx, FLUSH_INO);
2770 
2771 	/* update device state for checkpoint */
2772 	if (!f2fs_test_bit(devidx, (char *)&sbi->dirty_device)) {
2773 		spin_lock(&sbi->dev_lock);
2774 		f2fs_set_bit(devidx, (char *)&sbi->dirty_device);
2775 		spin_unlock(&sbi->dev_lock);
2776 	}
2777 }
2778 
2779 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
2780 {
2781 	int type = __get_segment_type(fio);
2782 	bool keep_order = (test_opt(fio->sbi, LFS) && type == CURSEG_COLD_DATA);
2783 
2784 	if (keep_order)
2785 		down_read(&fio->sbi->io_order_lock);
2786 reallocate:
2787 	f2fs_allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
2788 			&fio->new_blkaddr, sum, type, fio, true);
2789 
2790 	/* writeout dirty page into bdev */
2791 	f2fs_submit_page_write(fio);
2792 	if (fio->retry) {
2793 		fio->old_blkaddr = fio->new_blkaddr;
2794 		goto reallocate;
2795 	}
2796 
2797 	update_device_state(fio);
2798 
2799 	if (keep_order)
2800 		up_read(&fio->sbi->io_order_lock);
2801 }
2802 
2803 void f2fs_do_write_meta_page(struct f2fs_sb_info *sbi, struct page *page,
2804 					enum iostat_type io_type)
2805 {
2806 	struct f2fs_io_info fio = {
2807 		.sbi = sbi,
2808 		.type = META,
2809 		.temp = HOT,
2810 		.op = REQ_OP_WRITE,
2811 		.op_flags = REQ_SYNC | REQ_META | REQ_PRIO,
2812 		.old_blkaddr = page->index,
2813 		.new_blkaddr = page->index,
2814 		.page = page,
2815 		.encrypted_page = NULL,
2816 		.in_list = false,
2817 	};
2818 
2819 	if (unlikely(page->index >= MAIN_BLKADDR(sbi)))
2820 		fio.op_flags &= ~REQ_META;
2821 
2822 	set_page_writeback(page);
2823 	ClearPageError(page);
2824 	f2fs_submit_page_write(&fio);
2825 
2826 	f2fs_update_iostat(sbi, io_type, F2FS_BLKSIZE);
2827 }
2828 
2829 void f2fs_do_write_node_page(unsigned int nid, struct f2fs_io_info *fio)
2830 {
2831 	struct f2fs_summary sum;
2832 
2833 	set_summary(&sum, nid, 0, 0);
2834 	do_write_page(&sum, fio);
2835 
2836 	f2fs_update_iostat(fio->sbi, fio->io_type, F2FS_BLKSIZE);
2837 }
2838 
2839 void f2fs_outplace_write_data(struct dnode_of_data *dn,
2840 					struct f2fs_io_info *fio)
2841 {
2842 	struct f2fs_sb_info *sbi = fio->sbi;
2843 	struct f2fs_summary sum;
2844 	struct node_info ni;
2845 
2846 	f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
2847 	f2fs_get_node_info(sbi, dn->nid, &ni);
2848 	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
2849 	do_write_page(&sum, fio);
2850 	f2fs_update_data_blkaddr(dn, fio->new_blkaddr);
2851 
2852 	f2fs_update_iostat(sbi, fio->io_type, F2FS_BLKSIZE);
2853 }
2854 
2855 int f2fs_inplace_write_data(struct f2fs_io_info *fio)
2856 {
2857 	int err;
2858 	struct f2fs_sb_info *sbi = fio->sbi;
2859 
2860 	fio->new_blkaddr = fio->old_blkaddr;
2861 	/* i/o temperature is needed for passing down write hints */
2862 	__get_segment_type(fio);
2863 
2864 	f2fs_bug_on(sbi, !IS_DATASEG(get_seg_entry(sbi,
2865 			GET_SEGNO(sbi, fio->new_blkaddr))->type));
2866 
2867 	stat_inc_inplace_blocks(fio->sbi);
2868 
2869 	err = f2fs_submit_page_bio(fio);
2870 	if (!err)
2871 		update_device_state(fio);
2872 
2873 	f2fs_update_iostat(fio->sbi, fio->io_type, F2FS_BLKSIZE);
2874 
2875 	return err;
2876 }
2877 
2878 static inline int __f2fs_get_curseg(struct f2fs_sb_info *sbi,
2879 						unsigned int segno)
2880 {
2881 	int i;
2882 
2883 	for (i = CURSEG_HOT_DATA; i < NO_CHECK_TYPE; i++) {
2884 		if (CURSEG_I(sbi, i)->segno == segno)
2885 			break;
2886 	}
2887 	return i;
2888 }
2889 
2890 void f2fs_do_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
2891 				block_t old_blkaddr, block_t new_blkaddr,
2892 				bool recover_curseg, bool recover_newaddr)
2893 {
2894 	struct sit_info *sit_i = SIT_I(sbi);
2895 	struct curseg_info *curseg;
2896 	unsigned int segno, old_cursegno;
2897 	struct seg_entry *se;
2898 	int type;
2899 	unsigned short old_blkoff;
2900 
2901 	segno = GET_SEGNO(sbi, new_blkaddr);
2902 	se = get_seg_entry(sbi, segno);
2903 	type = se->type;
2904 
2905 	down_write(&SM_I(sbi)->curseg_lock);
2906 
2907 	if (!recover_curseg) {
2908 		/* for recovery flow */
2909 		if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
2910 			if (old_blkaddr == NULL_ADDR)
2911 				type = CURSEG_COLD_DATA;
2912 			else
2913 				type = CURSEG_WARM_DATA;
2914 		}
2915 	} else {
2916 		if (IS_CURSEG(sbi, segno)) {
2917 			/* se->type is volatile as SSR allocation */
2918 			type = __f2fs_get_curseg(sbi, segno);
2919 			f2fs_bug_on(sbi, type == NO_CHECK_TYPE);
2920 		} else {
2921 			type = CURSEG_WARM_DATA;
2922 		}
2923 	}
2924 
2925 	f2fs_bug_on(sbi, !IS_DATASEG(type));
2926 	curseg = CURSEG_I(sbi, type);
2927 
2928 	mutex_lock(&curseg->curseg_mutex);
2929 	down_write(&sit_i->sentry_lock);
2930 
2931 	old_cursegno = curseg->segno;
2932 	old_blkoff = curseg->next_blkoff;
2933 
2934 	/* change the current segment */
2935 	if (segno != curseg->segno) {
2936 		curseg->next_segno = segno;
2937 		change_curseg(sbi, type);
2938 	}
2939 
2940 	curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
2941 	__add_sum_entry(sbi, type, sum);
2942 
2943 	if (!recover_curseg || recover_newaddr)
2944 		update_sit_entry(sbi, new_blkaddr, 1);
2945 	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
2946 		update_sit_entry(sbi, old_blkaddr, -1);
2947 
2948 	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
2949 	locate_dirty_segment(sbi, GET_SEGNO(sbi, new_blkaddr));
2950 
2951 	locate_dirty_segment(sbi, old_cursegno);
2952 
2953 	if (recover_curseg) {
2954 		if (old_cursegno != curseg->segno) {
2955 			curseg->next_segno = old_cursegno;
2956 			change_curseg(sbi, type);
2957 		}
2958 		curseg->next_blkoff = old_blkoff;
2959 	}
2960 
2961 	up_write(&sit_i->sentry_lock);
2962 	mutex_unlock(&curseg->curseg_mutex);
2963 	up_write(&SM_I(sbi)->curseg_lock);
2964 }
2965 
2966 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
2967 				block_t old_addr, block_t new_addr,
2968 				unsigned char version, bool recover_curseg,
2969 				bool recover_newaddr)
2970 {
2971 	struct f2fs_summary sum;
2972 
2973 	set_summary(&sum, dn->nid, dn->ofs_in_node, version);
2974 
2975 	f2fs_do_replace_block(sbi, &sum, old_addr, new_addr,
2976 					recover_curseg, recover_newaddr);
2977 
2978 	f2fs_update_data_blkaddr(dn, new_addr);
2979 }
2980 
2981 void f2fs_wait_on_page_writeback(struct page *page,
2982 				enum page_type type, bool ordered)
2983 {
2984 	if (PageWriteback(page)) {
2985 		struct f2fs_sb_info *sbi = F2FS_P_SB(page);
2986 
2987 		f2fs_submit_merged_write_cond(sbi, page->mapping->host,
2988 						0, page->index, type);
2989 		if (ordered)
2990 			wait_on_page_writeback(page);
2991 		else
2992 			wait_for_stable_page(page);
2993 	}
2994 }
2995 
2996 void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr)
2997 {
2998 	struct page *cpage;
2999 
3000 	if (!is_valid_data_blkaddr(sbi, blkaddr))
3001 		return;
3002 
3003 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
3004 	if (cpage) {
3005 		f2fs_wait_on_page_writeback(cpage, DATA, true);
3006 		f2fs_put_page(cpage, 1);
3007 	}
3008 }
3009 
3010 static void read_compacted_summaries(struct f2fs_sb_info *sbi)
3011 {
3012 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3013 	struct curseg_info *seg_i;
3014 	unsigned char *kaddr;
3015 	struct page *page;
3016 	block_t start;
3017 	int i, j, offset;
3018 
3019 	start = start_sum_block(sbi);
3020 
3021 	page = f2fs_get_meta_page(sbi, start++);
3022 	kaddr = (unsigned char *)page_address(page);
3023 
3024 	/* Step 1: restore nat cache */
3025 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
3026 	memcpy(seg_i->journal, kaddr, SUM_JOURNAL_SIZE);
3027 
3028 	/* Step 2: restore sit cache */
3029 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
3030 	memcpy(seg_i->journal, kaddr + SUM_JOURNAL_SIZE, SUM_JOURNAL_SIZE);
3031 	offset = 2 * SUM_JOURNAL_SIZE;
3032 
3033 	/* Step 3: restore summary entries */
3034 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
3035 		unsigned short blk_off;
3036 		unsigned int segno;
3037 
3038 		seg_i = CURSEG_I(sbi, i);
3039 		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
3040 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
3041 		seg_i->next_segno = segno;
3042 		reset_curseg(sbi, i, 0);
3043 		seg_i->alloc_type = ckpt->alloc_type[i];
3044 		seg_i->next_blkoff = blk_off;
3045 
3046 		if (seg_i->alloc_type == SSR)
3047 			blk_off = sbi->blocks_per_seg;
3048 
3049 		for (j = 0; j < blk_off; j++) {
3050 			struct f2fs_summary *s;
3051 			s = (struct f2fs_summary *)(kaddr + offset);
3052 			seg_i->sum_blk->entries[j] = *s;
3053 			offset += SUMMARY_SIZE;
3054 			if (offset + SUMMARY_SIZE <= PAGE_SIZE -
3055 						SUM_FOOTER_SIZE)
3056 				continue;
3057 
3058 			f2fs_put_page(page, 1);
3059 			page = NULL;
3060 
3061 			page = f2fs_get_meta_page(sbi, start++);
3062 			kaddr = (unsigned char *)page_address(page);
3063 			offset = 0;
3064 		}
3065 	}
3066 	f2fs_put_page(page, 1);
3067 }
3068 
3069 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
3070 {
3071 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3072 	struct f2fs_summary_block *sum;
3073 	struct curseg_info *curseg;
3074 	struct page *new;
3075 	unsigned short blk_off;
3076 	unsigned int segno = 0;
3077 	block_t blk_addr = 0;
3078 
3079 	/* get segment number and block addr */
3080 	if (IS_DATASEG(type)) {
3081 		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
3082 		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
3083 							CURSEG_HOT_DATA]);
3084 		if (__exist_node_summaries(sbi))
3085 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
3086 		else
3087 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
3088 	} else {
3089 		segno = le32_to_cpu(ckpt->cur_node_segno[type -
3090 							CURSEG_HOT_NODE]);
3091 		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
3092 							CURSEG_HOT_NODE]);
3093 		if (__exist_node_summaries(sbi))
3094 			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
3095 							type - CURSEG_HOT_NODE);
3096 		else
3097 			blk_addr = GET_SUM_BLOCK(sbi, segno);
3098 	}
3099 
3100 	new = f2fs_get_meta_page(sbi, blk_addr);
3101 	sum = (struct f2fs_summary_block *)page_address(new);
3102 
3103 	if (IS_NODESEG(type)) {
3104 		if (__exist_node_summaries(sbi)) {
3105 			struct f2fs_summary *ns = &sum->entries[0];
3106 			int i;
3107 			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
3108 				ns->version = 0;
3109 				ns->ofs_in_node = 0;
3110 			}
3111 		} else {
3112 			f2fs_restore_node_summary(sbi, segno, sum);
3113 		}
3114 	}
3115 
3116 	/* set uncompleted segment to curseg */
3117 	curseg = CURSEG_I(sbi, type);
3118 	mutex_lock(&curseg->curseg_mutex);
3119 
3120 	/* update journal info */
3121 	down_write(&curseg->journal_rwsem);
3122 	memcpy(curseg->journal, &sum->journal, SUM_JOURNAL_SIZE);
3123 	up_write(&curseg->journal_rwsem);
3124 
3125 	memcpy(curseg->sum_blk->entries, sum->entries, SUM_ENTRY_SIZE);
3126 	memcpy(&curseg->sum_blk->footer, &sum->footer, SUM_FOOTER_SIZE);
3127 	curseg->next_segno = segno;
3128 	reset_curseg(sbi, type, 0);
3129 	curseg->alloc_type = ckpt->alloc_type[type];
3130 	curseg->next_blkoff = blk_off;
3131 	mutex_unlock(&curseg->curseg_mutex);
3132 	f2fs_put_page(new, 1);
3133 	return 0;
3134 }
3135 
3136 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
3137 {
3138 	struct f2fs_journal *sit_j = CURSEG_I(sbi, CURSEG_COLD_DATA)->journal;
3139 	struct f2fs_journal *nat_j = CURSEG_I(sbi, CURSEG_HOT_DATA)->journal;
3140 	int type = CURSEG_HOT_DATA;
3141 	int err;
3142 
3143 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG)) {
3144 		int npages = f2fs_npages_for_summary_flush(sbi, true);
3145 
3146 		if (npages >= 2)
3147 			f2fs_ra_meta_pages(sbi, start_sum_block(sbi), npages,
3148 							META_CP, true);
3149 
3150 		/* restore for compacted data summary */
3151 		read_compacted_summaries(sbi);
3152 		type = CURSEG_HOT_NODE;
3153 	}
3154 
3155 	if (__exist_node_summaries(sbi))
3156 		f2fs_ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
3157 					NR_CURSEG_TYPE - type, META_CP, true);
3158 
3159 	for (; type <= CURSEG_COLD_NODE; type++) {
3160 		err = read_normal_summaries(sbi, type);
3161 		if (err)
3162 			return err;
3163 	}
3164 
3165 	/* sanity check for summary blocks */
3166 	if (nats_in_cursum(nat_j) > NAT_JOURNAL_ENTRIES ||
3167 			sits_in_cursum(sit_j) > SIT_JOURNAL_ENTRIES)
3168 		return -EINVAL;
3169 
3170 	return 0;
3171 }
3172 
3173 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
3174 {
3175 	struct page *page;
3176 	unsigned char *kaddr;
3177 	struct f2fs_summary *summary;
3178 	struct curseg_info *seg_i;
3179 	int written_size = 0;
3180 	int i, j;
3181 
3182 	page = f2fs_grab_meta_page(sbi, blkaddr++);
3183 	kaddr = (unsigned char *)page_address(page);
3184 	memset(kaddr, 0, PAGE_SIZE);
3185 
3186 	/* Step 1: write nat cache */
3187 	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
3188 	memcpy(kaddr, seg_i->journal, SUM_JOURNAL_SIZE);
3189 	written_size += SUM_JOURNAL_SIZE;
3190 
3191 	/* Step 2: write sit cache */
3192 	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
3193 	memcpy(kaddr + written_size, seg_i->journal, SUM_JOURNAL_SIZE);
3194 	written_size += SUM_JOURNAL_SIZE;
3195 
3196 	/* Step 3: write summary entries */
3197 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
3198 		unsigned short blkoff;
3199 		seg_i = CURSEG_I(sbi, i);
3200 		if (sbi->ckpt->alloc_type[i] == SSR)
3201 			blkoff = sbi->blocks_per_seg;
3202 		else
3203 			blkoff = curseg_blkoff(sbi, i);
3204 
3205 		for (j = 0; j < blkoff; j++) {
3206 			if (!page) {
3207 				page = f2fs_grab_meta_page(sbi, blkaddr++);
3208 				kaddr = (unsigned char *)page_address(page);
3209 				memset(kaddr, 0, PAGE_SIZE);
3210 				written_size = 0;
3211 			}
3212 			summary = (struct f2fs_summary *)(kaddr + written_size);
3213 			*summary = seg_i->sum_blk->entries[j];
3214 			written_size += SUMMARY_SIZE;
3215 
3216 			if (written_size + SUMMARY_SIZE <= PAGE_SIZE -
3217 							SUM_FOOTER_SIZE)
3218 				continue;
3219 
3220 			set_page_dirty(page);
3221 			f2fs_put_page(page, 1);
3222 			page = NULL;
3223 		}
3224 	}
3225 	if (page) {
3226 		set_page_dirty(page);
3227 		f2fs_put_page(page, 1);
3228 	}
3229 }
3230 
3231 static void write_normal_summaries(struct f2fs_sb_info *sbi,
3232 					block_t blkaddr, int type)
3233 {
3234 	int i, end;
3235 	if (IS_DATASEG(type))
3236 		end = type + NR_CURSEG_DATA_TYPE;
3237 	else
3238 		end = type + NR_CURSEG_NODE_TYPE;
3239 
3240 	for (i = type; i < end; i++)
3241 		write_current_sum_page(sbi, i, blkaddr + (i - type));
3242 }
3243 
3244 void f2fs_write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
3245 {
3246 	if (is_set_ckpt_flags(sbi, CP_COMPACT_SUM_FLAG))
3247 		write_compacted_summaries(sbi, start_blk);
3248 	else
3249 		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
3250 }
3251 
3252 void f2fs_write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
3253 {
3254 	write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
3255 }
3256 
3257 int f2fs_lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
3258 					unsigned int val, int alloc)
3259 {
3260 	int i;
3261 
3262 	if (type == NAT_JOURNAL) {
3263 		for (i = 0; i < nats_in_cursum(journal); i++) {
3264 			if (le32_to_cpu(nid_in_journal(journal, i)) == val)
3265 				return i;
3266 		}
3267 		if (alloc && __has_cursum_space(journal, 1, NAT_JOURNAL))
3268 			return update_nats_in_cursum(journal, 1);
3269 	} else if (type == SIT_JOURNAL) {
3270 		for (i = 0; i < sits_in_cursum(journal); i++)
3271 			if (le32_to_cpu(segno_in_journal(journal, i)) == val)
3272 				return i;
3273 		if (alloc && __has_cursum_space(journal, 1, SIT_JOURNAL))
3274 			return update_sits_in_cursum(journal, 1);
3275 	}
3276 	return -1;
3277 }
3278 
3279 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
3280 					unsigned int segno)
3281 {
3282 	return f2fs_get_meta_page(sbi, current_sit_addr(sbi, segno));
3283 }
3284 
3285 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
3286 					unsigned int start)
3287 {
3288 	struct sit_info *sit_i = SIT_I(sbi);
3289 	struct page *page;
3290 	pgoff_t src_off, dst_off;
3291 
3292 	src_off = current_sit_addr(sbi, start);
3293 	dst_off = next_sit_addr(sbi, src_off);
3294 
3295 	page = f2fs_grab_meta_page(sbi, dst_off);
3296 	seg_info_to_sit_page(sbi, page, start);
3297 
3298 	set_page_dirty(page);
3299 	set_to_next_sit(sit_i, start);
3300 
3301 	return page;
3302 }
3303 
3304 static struct sit_entry_set *grab_sit_entry_set(void)
3305 {
3306 	struct sit_entry_set *ses =
3307 			f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
3308 
3309 	ses->entry_cnt = 0;
3310 	INIT_LIST_HEAD(&ses->set_list);
3311 	return ses;
3312 }
3313 
3314 static void release_sit_entry_set(struct sit_entry_set *ses)
3315 {
3316 	list_del(&ses->set_list);
3317 	kmem_cache_free(sit_entry_set_slab, ses);
3318 }
3319 
3320 static void adjust_sit_entry_set(struct sit_entry_set *ses,
3321 						struct list_head *head)
3322 {
3323 	struct sit_entry_set *next = ses;
3324 
3325 	if (list_is_last(&ses->set_list, head))
3326 		return;
3327 
3328 	list_for_each_entry_continue(next, head, set_list)
3329 		if (ses->entry_cnt <= next->entry_cnt)
3330 			break;
3331 
3332 	list_move_tail(&ses->set_list, &next->set_list);
3333 }
3334 
3335 static void add_sit_entry(unsigned int segno, struct list_head *head)
3336 {
3337 	struct sit_entry_set *ses;
3338 	unsigned int start_segno = START_SEGNO(segno);
3339 
3340 	list_for_each_entry(ses, head, set_list) {
3341 		if (ses->start_segno == start_segno) {
3342 			ses->entry_cnt++;
3343 			adjust_sit_entry_set(ses, head);
3344 			return;
3345 		}
3346 	}
3347 
3348 	ses = grab_sit_entry_set();
3349 
3350 	ses->start_segno = start_segno;
3351 	ses->entry_cnt++;
3352 	list_add(&ses->set_list, head);
3353 }
3354 
3355 static void add_sits_in_set(struct f2fs_sb_info *sbi)
3356 {
3357 	struct f2fs_sm_info *sm_info = SM_I(sbi);
3358 	struct list_head *set_list = &sm_info->sit_entry_set;
3359 	unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
3360 	unsigned int segno;
3361 
3362 	for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
3363 		add_sit_entry(segno, set_list);
3364 }
3365 
3366 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
3367 {
3368 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3369 	struct f2fs_journal *journal = curseg->journal;
3370 	int i;
3371 
3372 	down_write(&curseg->journal_rwsem);
3373 	for (i = 0; i < sits_in_cursum(journal); i++) {
3374 		unsigned int segno;
3375 		bool dirtied;
3376 
3377 		segno = le32_to_cpu(segno_in_journal(journal, i));
3378 		dirtied = __mark_sit_entry_dirty(sbi, segno);
3379 
3380 		if (!dirtied)
3381 			add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
3382 	}
3383 	update_sits_in_cursum(journal, -i);
3384 	up_write(&curseg->journal_rwsem);
3385 }
3386 
3387 /*
3388  * CP calls this function, which flushes SIT entries including sit_journal,
3389  * and moves prefree segs to free segs.
3390  */
3391 void f2fs_flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
3392 {
3393 	struct sit_info *sit_i = SIT_I(sbi);
3394 	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
3395 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3396 	struct f2fs_journal *journal = curseg->journal;
3397 	struct sit_entry_set *ses, *tmp;
3398 	struct list_head *head = &SM_I(sbi)->sit_entry_set;
3399 	bool to_journal = true;
3400 	struct seg_entry *se;
3401 
3402 	down_write(&sit_i->sentry_lock);
3403 
3404 	if (!sit_i->dirty_sentries)
3405 		goto out;
3406 
3407 	/*
3408 	 * add and account sit entries of dirty bitmap in sit entry
3409 	 * set temporarily
3410 	 */
3411 	add_sits_in_set(sbi);
3412 
3413 	/*
3414 	 * if there are no enough space in journal to store dirty sit
3415 	 * entries, remove all entries from journal and add and account
3416 	 * them in sit entry set.
3417 	 */
3418 	if (!__has_cursum_space(journal, sit_i->dirty_sentries, SIT_JOURNAL))
3419 		remove_sits_in_journal(sbi);
3420 
3421 	/*
3422 	 * there are two steps to flush sit entries:
3423 	 * #1, flush sit entries to journal in current cold data summary block.
3424 	 * #2, flush sit entries to sit page.
3425 	 */
3426 	list_for_each_entry_safe(ses, tmp, head, set_list) {
3427 		struct page *page = NULL;
3428 		struct f2fs_sit_block *raw_sit = NULL;
3429 		unsigned int start_segno = ses->start_segno;
3430 		unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
3431 						(unsigned long)MAIN_SEGS(sbi));
3432 		unsigned int segno = start_segno;
3433 
3434 		if (to_journal &&
3435 			!__has_cursum_space(journal, ses->entry_cnt, SIT_JOURNAL))
3436 			to_journal = false;
3437 
3438 		if (to_journal) {
3439 			down_write(&curseg->journal_rwsem);
3440 		} else {
3441 			page = get_next_sit_page(sbi, start_segno);
3442 			raw_sit = page_address(page);
3443 		}
3444 
3445 		/* flush dirty sit entries in region of current sit set */
3446 		for_each_set_bit_from(segno, bitmap, end) {
3447 			int offset, sit_offset;
3448 
3449 			se = get_seg_entry(sbi, segno);
3450 #ifdef CONFIG_F2FS_CHECK_FS
3451 			if (memcmp(se->cur_valid_map, se->cur_valid_map_mir,
3452 						SIT_VBLOCK_MAP_SIZE))
3453 				f2fs_bug_on(sbi, 1);
3454 #endif
3455 
3456 			/* add discard candidates */
3457 			if (!(cpc->reason & CP_DISCARD)) {
3458 				cpc->trim_start = segno;
3459 				add_discard_addrs(sbi, cpc, false);
3460 			}
3461 
3462 			if (to_journal) {
3463 				offset = f2fs_lookup_journal_in_cursum(journal,
3464 							SIT_JOURNAL, segno, 1);
3465 				f2fs_bug_on(sbi, offset < 0);
3466 				segno_in_journal(journal, offset) =
3467 							cpu_to_le32(segno);
3468 				seg_info_to_raw_sit(se,
3469 					&sit_in_journal(journal, offset));
3470 				check_block_count(sbi, segno,
3471 					&sit_in_journal(journal, offset));
3472 			} else {
3473 				sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
3474 				seg_info_to_raw_sit(se,
3475 						&raw_sit->entries[sit_offset]);
3476 				check_block_count(sbi, segno,
3477 						&raw_sit->entries[sit_offset]);
3478 			}
3479 
3480 			__clear_bit(segno, bitmap);
3481 			sit_i->dirty_sentries--;
3482 			ses->entry_cnt--;
3483 		}
3484 
3485 		if (to_journal)
3486 			up_write(&curseg->journal_rwsem);
3487 		else
3488 			f2fs_put_page(page, 1);
3489 
3490 		f2fs_bug_on(sbi, ses->entry_cnt);
3491 		release_sit_entry_set(ses);
3492 	}
3493 
3494 	f2fs_bug_on(sbi, !list_empty(head));
3495 	f2fs_bug_on(sbi, sit_i->dirty_sentries);
3496 out:
3497 	if (cpc->reason & CP_DISCARD) {
3498 		__u64 trim_start = cpc->trim_start;
3499 
3500 		for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
3501 			add_discard_addrs(sbi, cpc, false);
3502 
3503 		cpc->trim_start = trim_start;
3504 	}
3505 	up_write(&sit_i->sentry_lock);
3506 
3507 	set_prefree_as_free_segments(sbi);
3508 }
3509 
3510 static int build_sit_info(struct f2fs_sb_info *sbi)
3511 {
3512 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
3513 	struct sit_info *sit_i;
3514 	unsigned int sit_segs, start;
3515 	char *src_bitmap;
3516 	unsigned int bitmap_size;
3517 
3518 	/* allocate memory for SIT information */
3519 	sit_i = f2fs_kzalloc(sbi, sizeof(struct sit_info), GFP_KERNEL);
3520 	if (!sit_i)
3521 		return -ENOMEM;
3522 
3523 	SM_I(sbi)->sit_info = sit_i;
3524 
3525 	sit_i->sentries =
3526 		f2fs_kvzalloc(sbi, array_size(sizeof(struct seg_entry),
3527 					      MAIN_SEGS(sbi)),
3528 			      GFP_KERNEL);
3529 	if (!sit_i->sentries)
3530 		return -ENOMEM;
3531 
3532 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3533 	sit_i->dirty_sentries_bitmap = f2fs_kvzalloc(sbi, bitmap_size,
3534 								GFP_KERNEL);
3535 	if (!sit_i->dirty_sentries_bitmap)
3536 		return -ENOMEM;
3537 
3538 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
3539 		sit_i->sentries[start].cur_valid_map
3540 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3541 		sit_i->sentries[start].ckpt_valid_map
3542 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3543 		if (!sit_i->sentries[start].cur_valid_map ||
3544 				!sit_i->sentries[start].ckpt_valid_map)
3545 			return -ENOMEM;
3546 
3547 #ifdef CONFIG_F2FS_CHECK_FS
3548 		sit_i->sentries[start].cur_valid_map_mir
3549 			= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3550 		if (!sit_i->sentries[start].cur_valid_map_mir)
3551 			return -ENOMEM;
3552 #endif
3553 
3554 		if (f2fs_discard_en(sbi)) {
3555 			sit_i->sentries[start].discard_map
3556 				= f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE,
3557 								GFP_KERNEL);
3558 			if (!sit_i->sentries[start].discard_map)
3559 				return -ENOMEM;
3560 		}
3561 	}
3562 
3563 	sit_i->tmp_map = f2fs_kzalloc(sbi, SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
3564 	if (!sit_i->tmp_map)
3565 		return -ENOMEM;
3566 
3567 	if (sbi->segs_per_sec > 1) {
3568 		sit_i->sec_entries =
3569 			f2fs_kvzalloc(sbi, array_size(sizeof(struct sec_entry),
3570 						      MAIN_SECS(sbi)),
3571 				      GFP_KERNEL);
3572 		if (!sit_i->sec_entries)
3573 			return -ENOMEM;
3574 	}
3575 
3576 	/* get information related with SIT */
3577 	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
3578 
3579 	/* setup SIT bitmap from ckeckpoint pack */
3580 	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
3581 	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
3582 
3583 	sit_i->sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
3584 	if (!sit_i->sit_bitmap)
3585 		return -ENOMEM;
3586 
3587 #ifdef CONFIG_F2FS_CHECK_FS
3588 	sit_i->sit_bitmap_mir = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
3589 	if (!sit_i->sit_bitmap_mir)
3590 		return -ENOMEM;
3591 #endif
3592 
3593 	/* init SIT information */
3594 	sit_i->s_ops = &default_salloc_ops;
3595 
3596 	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
3597 	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
3598 	sit_i->written_valid_blocks = 0;
3599 	sit_i->bitmap_size = bitmap_size;
3600 	sit_i->dirty_sentries = 0;
3601 	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
3602 	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
3603 	sit_i->mounted_time = ktime_get_real_seconds();
3604 	init_rwsem(&sit_i->sentry_lock);
3605 	return 0;
3606 }
3607 
3608 static int build_free_segmap(struct f2fs_sb_info *sbi)
3609 {
3610 	struct free_segmap_info *free_i;
3611 	unsigned int bitmap_size, sec_bitmap_size;
3612 
3613 	/* allocate memory for free segmap information */
3614 	free_i = f2fs_kzalloc(sbi, sizeof(struct free_segmap_info), GFP_KERNEL);
3615 	if (!free_i)
3616 		return -ENOMEM;
3617 
3618 	SM_I(sbi)->free_info = free_i;
3619 
3620 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3621 	free_i->free_segmap = f2fs_kvmalloc(sbi, bitmap_size, GFP_KERNEL);
3622 	if (!free_i->free_segmap)
3623 		return -ENOMEM;
3624 
3625 	sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
3626 	free_i->free_secmap = f2fs_kvmalloc(sbi, sec_bitmap_size, GFP_KERNEL);
3627 	if (!free_i->free_secmap)
3628 		return -ENOMEM;
3629 
3630 	/* set all segments as dirty temporarily */
3631 	memset(free_i->free_segmap, 0xff, bitmap_size);
3632 	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
3633 
3634 	/* init free segmap information */
3635 	free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
3636 	free_i->free_segments = 0;
3637 	free_i->free_sections = 0;
3638 	spin_lock_init(&free_i->segmap_lock);
3639 	return 0;
3640 }
3641 
3642 static int build_curseg(struct f2fs_sb_info *sbi)
3643 {
3644 	struct curseg_info *array;
3645 	int i;
3646 
3647 	array = f2fs_kzalloc(sbi, array_size(NR_CURSEG_TYPE, sizeof(*array)),
3648 			     GFP_KERNEL);
3649 	if (!array)
3650 		return -ENOMEM;
3651 
3652 	SM_I(sbi)->curseg_array = array;
3653 
3654 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
3655 		mutex_init(&array[i].curseg_mutex);
3656 		array[i].sum_blk = f2fs_kzalloc(sbi, PAGE_SIZE, GFP_KERNEL);
3657 		if (!array[i].sum_blk)
3658 			return -ENOMEM;
3659 		init_rwsem(&array[i].journal_rwsem);
3660 		array[i].journal = f2fs_kzalloc(sbi,
3661 				sizeof(struct f2fs_journal), GFP_KERNEL);
3662 		if (!array[i].journal)
3663 			return -ENOMEM;
3664 		array[i].segno = NULL_SEGNO;
3665 		array[i].next_blkoff = 0;
3666 	}
3667 	return restore_curseg_summaries(sbi);
3668 }
3669 
3670 static int build_sit_entries(struct f2fs_sb_info *sbi)
3671 {
3672 	struct sit_info *sit_i = SIT_I(sbi);
3673 	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
3674 	struct f2fs_journal *journal = curseg->journal;
3675 	struct seg_entry *se;
3676 	struct f2fs_sit_entry sit;
3677 	int sit_blk_cnt = SIT_BLK_CNT(sbi);
3678 	unsigned int i, start, end;
3679 	unsigned int readed, start_blk = 0;
3680 	int err = 0;
3681 	block_t total_node_blocks = 0;
3682 
3683 	do {
3684 		readed = f2fs_ra_meta_pages(sbi, start_blk, BIO_MAX_PAGES,
3685 							META_SIT, true);
3686 
3687 		start = start_blk * sit_i->sents_per_block;
3688 		end = (start_blk + readed) * sit_i->sents_per_block;
3689 
3690 		for (; start < end && start < MAIN_SEGS(sbi); start++) {
3691 			struct f2fs_sit_block *sit_blk;
3692 			struct page *page;
3693 
3694 			se = &sit_i->sentries[start];
3695 			page = get_current_sit_page(sbi, start);
3696 			sit_blk = (struct f2fs_sit_block *)page_address(page);
3697 			sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
3698 			f2fs_put_page(page, 1);
3699 
3700 			err = check_block_count(sbi, start, &sit);
3701 			if (err)
3702 				return err;
3703 			seg_info_from_raw_sit(se, &sit);
3704 			if (IS_NODESEG(se->type))
3705 				total_node_blocks += se->valid_blocks;
3706 
3707 			/* build discard map only one time */
3708 			if (f2fs_discard_en(sbi)) {
3709 				if (is_set_ckpt_flags(sbi, CP_TRIMMED_FLAG)) {
3710 					memset(se->discard_map, 0xff,
3711 						SIT_VBLOCK_MAP_SIZE);
3712 				} else {
3713 					memcpy(se->discard_map,
3714 						se->cur_valid_map,
3715 						SIT_VBLOCK_MAP_SIZE);
3716 					sbi->discard_blks +=
3717 						sbi->blocks_per_seg -
3718 						se->valid_blocks;
3719 				}
3720 			}
3721 
3722 			if (sbi->segs_per_sec > 1)
3723 				get_sec_entry(sbi, start)->valid_blocks +=
3724 							se->valid_blocks;
3725 		}
3726 		start_blk += readed;
3727 	} while (start_blk < sit_blk_cnt);
3728 
3729 	down_read(&curseg->journal_rwsem);
3730 	for (i = 0; i < sits_in_cursum(journal); i++) {
3731 		unsigned int old_valid_blocks;
3732 
3733 		start = le32_to_cpu(segno_in_journal(journal, i));
3734 		if (start >= MAIN_SEGS(sbi)) {
3735 			f2fs_msg(sbi->sb, KERN_ERR,
3736 					"Wrong journal entry on segno %u",
3737 					start);
3738 			set_sbi_flag(sbi, SBI_NEED_FSCK);
3739 			err = -EINVAL;
3740 			break;
3741 		}
3742 
3743 		se = &sit_i->sentries[start];
3744 		sit = sit_in_journal(journal, i);
3745 
3746 		old_valid_blocks = se->valid_blocks;
3747 		if (IS_NODESEG(se->type))
3748 			total_node_blocks -= old_valid_blocks;
3749 
3750 		err = check_block_count(sbi, start, &sit);
3751 		if (err)
3752 			break;
3753 		seg_info_from_raw_sit(se, &sit);
3754 		if (IS_NODESEG(se->type))
3755 			total_node_blocks += se->valid_blocks;
3756 
3757 		if (f2fs_discard_en(sbi)) {
3758 			if (is_set_ckpt_flags(sbi, CP_TRIMMED_FLAG)) {
3759 				memset(se->discard_map, 0xff,
3760 							SIT_VBLOCK_MAP_SIZE);
3761 			} else {
3762 				memcpy(se->discard_map, se->cur_valid_map,
3763 							SIT_VBLOCK_MAP_SIZE);
3764 				sbi->discard_blks += old_valid_blocks;
3765 				sbi->discard_blks -= se->valid_blocks;
3766 			}
3767 		}
3768 
3769 		if (sbi->segs_per_sec > 1) {
3770 			get_sec_entry(sbi, start)->valid_blocks +=
3771 							se->valid_blocks;
3772 			get_sec_entry(sbi, start)->valid_blocks -=
3773 							old_valid_blocks;
3774 		}
3775 	}
3776 	up_read(&curseg->journal_rwsem);
3777 
3778 	if (!err && total_node_blocks != valid_node_count(sbi)) {
3779 		f2fs_msg(sbi->sb, KERN_ERR,
3780 			"SIT is corrupted node# %u vs %u",
3781 			total_node_blocks, valid_node_count(sbi));
3782 		set_sbi_flag(sbi, SBI_NEED_FSCK);
3783 		err = -EINVAL;
3784 	}
3785 
3786 	return err;
3787 }
3788 
3789 static void init_free_segmap(struct f2fs_sb_info *sbi)
3790 {
3791 	unsigned int start;
3792 	int type;
3793 
3794 	for (start = 0; start < MAIN_SEGS(sbi); start++) {
3795 		struct seg_entry *sentry = get_seg_entry(sbi, start);
3796 		if (!sentry->valid_blocks)
3797 			__set_free(sbi, start);
3798 		else
3799 			SIT_I(sbi)->written_valid_blocks +=
3800 						sentry->valid_blocks;
3801 	}
3802 
3803 	/* set use the current segments */
3804 	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
3805 		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
3806 		__set_test_and_inuse(sbi, curseg_t->segno);
3807 	}
3808 }
3809 
3810 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
3811 {
3812 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3813 	struct free_segmap_info *free_i = FREE_I(sbi);
3814 	unsigned int segno = 0, offset = 0;
3815 	unsigned short valid_blocks;
3816 
3817 	while (1) {
3818 		/* find dirty segment based on free segmap */
3819 		segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
3820 		if (segno >= MAIN_SEGS(sbi))
3821 			break;
3822 		offset = segno + 1;
3823 		valid_blocks = get_valid_blocks(sbi, segno, false);
3824 		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
3825 			continue;
3826 		if (valid_blocks > sbi->blocks_per_seg) {
3827 			f2fs_bug_on(sbi, 1);
3828 			continue;
3829 		}
3830 		mutex_lock(&dirty_i->seglist_lock);
3831 		__locate_dirty_segment(sbi, segno, DIRTY);
3832 		mutex_unlock(&dirty_i->seglist_lock);
3833 	}
3834 }
3835 
3836 static int init_victim_secmap(struct f2fs_sb_info *sbi)
3837 {
3838 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3839 	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
3840 
3841 	dirty_i->victim_secmap = f2fs_kvzalloc(sbi, bitmap_size, GFP_KERNEL);
3842 	if (!dirty_i->victim_secmap)
3843 		return -ENOMEM;
3844 	return 0;
3845 }
3846 
3847 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
3848 {
3849 	struct dirty_seglist_info *dirty_i;
3850 	unsigned int bitmap_size, i;
3851 
3852 	/* allocate memory for dirty segments list information */
3853 	dirty_i = f2fs_kzalloc(sbi, sizeof(struct dirty_seglist_info),
3854 								GFP_KERNEL);
3855 	if (!dirty_i)
3856 		return -ENOMEM;
3857 
3858 	SM_I(sbi)->dirty_info = dirty_i;
3859 	mutex_init(&dirty_i->seglist_lock);
3860 
3861 	bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
3862 
3863 	for (i = 0; i < NR_DIRTY_TYPE; i++) {
3864 		dirty_i->dirty_segmap[i] = f2fs_kvzalloc(sbi, bitmap_size,
3865 								GFP_KERNEL);
3866 		if (!dirty_i->dirty_segmap[i])
3867 			return -ENOMEM;
3868 	}
3869 
3870 	init_dirty_segmap(sbi);
3871 	return init_victim_secmap(sbi);
3872 }
3873 
3874 /*
3875  * Update min, max modified time for cost-benefit GC algorithm
3876  */
3877 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
3878 {
3879 	struct sit_info *sit_i = SIT_I(sbi);
3880 	unsigned int segno;
3881 
3882 	down_write(&sit_i->sentry_lock);
3883 
3884 	sit_i->min_mtime = ULLONG_MAX;
3885 
3886 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
3887 		unsigned int i;
3888 		unsigned long long mtime = 0;
3889 
3890 		for (i = 0; i < sbi->segs_per_sec; i++)
3891 			mtime += get_seg_entry(sbi, segno + i)->mtime;
3892 
3893 		mtime = div_u64(mtime, sbi->segs_per_sec);
3894 
3895 		if (sit_i->min_mtime > mtime)
3896 			sit_i->min_mtime = mtime;
3897 	}
3898 	sit_i->max_mtime = get_mtime(sbi, false);
3899 	up_write(&sit_i->sentry_lock);
3900 }
3901 
3902 int f2fs_build_segment_manager(struct f2fs_sb_info *sbi)
3903 {
3904 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
3905 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
3906 	struct f2fs_sm_info *sm_info;
3907 	int err;
3908 
3909 	sm_info = f2fs_kzalloc(sbi, sizeof(struct f2fs_sm_info), GFP_KERNEL);
3910 	if (!sm_info)
3911 		return -ENOMEM;
3912 
3913 	/* init sm info */
3914 	sbi->sm_info = sm_info;
3915 	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
3916 	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
3917 	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
3918 	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
3919 	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
3920 	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
3921 	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
3922 	sm_info->rec_prefree_segments = sm_info->main_segments *
3923 					DEF_RECLAIM_PREFREE_SEGMENTS / 100;
3924 	if (sm_info->rec_prefree_segments > DEF_MAX_RECLAIM_PREFREE_SEGMENTS)
3925 		sm_info->rec_prefree_segments = DEF_MAX_RECLAIM_PREFREE_SEGMENTS;
3926 
3927 	if (!test_opt(sbi, LFS))
3928 		sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
3929 	sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
3930 	sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
3931 	sm_info->min_hot_blocks = DEF_MIN_HOT_BLOCKS;
3932 	sm_info->min_ssr_sections = reserved_sections(sbi);
3933 
3934 	INIT_LIST_HEAD(&sm_info->sit_entry_set);
3935 
3936 	init_rwsem(&sm_info->curseg_lock);
3937 
3938 	if (!f2fs_readonly(sbi->sb)) {
3939 		err = f2fs_create_flush_cmd_control(sbi);
3940 		if (err)
3941 			return err;
3942 	}
3943 
3944 	err = create_discard_cmd_control(sbi);
3945 	if (err)
3946 		return err;
3947 
3948 	err = build_sit_info(sbi);
3949 	if (err)
3950 		return err;
3951 	err = build_free_segmap(sbi);
3952 	if (err)
3953 		return err;
3954 	err = build_curseg(sbi);
3955 	if (err)
3956 		return err;
3957 
3958 	/* reinit free segmap based on SIT */
3959 	err = build_sit_entries(sbi);
3960 	if (err)
3961 		return err;
3962 
3963 	init_free_segmap(sbi);
3964 	err = build_dirty_segmap(sbi);
3965 	if (err)
3966 		return err;
3967 
3968 	init_min_max_mtime(sbi);
3969 	return 0;
3970 }
3971 
3972 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
3973 		enum dirty_type dirty_type)
3974 {
3975 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3976 
3977 	mutex_lock(&dirty_i->seglist_lock);
3978 	kvfree(dirty_i->dirty_segmap[dirty_type]);
3979 	dirty_i->nr_dirty[dirty_type] = 0;
3980 	mutex_unlock(&dirty_i->seglist_lock);
3981 }
3982 
3983 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
3984 {
3985 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3986 	kvfree(dirty_i->victim_secmap);
3987 }
3988 
3989 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
3990 {
3991 	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
3992 	int i;
3993 
3994 	if (!dirty_i)
3995 		return;
3996 
3997 	/* discard pre-free/dirty segments list */
3998 	for (i = 0; i < NR_DIRTY_TYPE; i++)
3999 		discard_dirty_segmap(sbi, i);
4000 
4001 	destroy_victim_secmap(sbi);
4002 	SM_I(sbi)->dirty_info = NULL;
4003 	kfree(dirty_i);
4004 }
4005 
4006 static void destroy_curseg(struct f2fs_sb_info *sbi)
4007 {
4008 	struct curseg_info *array = SM_I(sbi)->curseg_array;
4009 	int i;
4010 
4011 	if (!array)
4012 		return;
4013 	SM_I(sbi)->curseg_array = NULL;
4014 	for (i = 0; i < NR_CURSEG_TYPE; i++) {
4015 		kfree(array[i].sum_blk);
4016 		kfree(array[i].journal);
4017 	}
4018 	kfree(array);
4019 }
4020 
4021 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
4022 {
4023 	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
4024 	if (!free_i)
4025 		return;
4026 	SM_I(sbi)->free_info = NULL;
4027 	kvfree(free_i->free_segmap);
4028 	kvfree(free_i->free_secmap);
4029 	kfree(free_i);
4030 }
4031 
4032 static void destroy_sit_info(struct f2fs_sb_info *sbi)
4033 {
4034 	struct sit_info *sit_i = SIT_I(sbi);
4035 	unsigned int start;
4036 
4037 	if (!sit_i)
4038 		return;
4039 
4040 	if (sit_i->sentries) {
4041 		for (start = 0; start < MAIN_SEGS(sbi); start++) {
4042 			kfree(sit_i->sentries[start].cur_valid_map);
4043 #ifdef CONFIG_F2FS_CHECK_FS
4044 			kfree(sit_i->sentries[start].cur_valid_map_mir);
4045 #endif
4046 			kfree(sit_i->sentries[start].ckpt_valid_map);
4047 			kfree(sit_i->sentries[start].discard_map);
4048 		}
4049 	}
4050 	kfree(sit_i->tmp_map);
4051 
4052 	kvfree(sit_i->sentries);
4053 	kvfree(sit_i->sec_entries);
4054 	kvfree(sit_i->dirty_sentries_bitmap);
4055 
4056 	SM_I(sbi)->sit_info = NULL;
4057 	kfree(sit_i->sit_bitmap);
4058 #ifdef CONFIG_F2FS_CHECK_FS
4059 	kfree(sit_i->sit_bitmap_mir);
4060 #endif
4061 	kfree(sit_i);
4062 }
4063 
4064 void f2fs_destroy_segment_manager(struct f2fs_sb_info *sbi)
4065 {
4066 	struct f2fs_sm_info *sm_info = SM_I(sbi);
4067 
4068 	if (!sm_info)
4069 		return;
4070 	f2fs_destroy_flush_cmd_control(sbi, true);
4071 	destroy_discard_cmd_control(sbi);
4072 	destroy_dirty_segmap(sbi);
4073 	destroy_curseg(sbi);
4074 	destroy_free_segmap(sbi);
4075 	destroy_sit_info(sbi);
4076 	sbi->sm_info = NULL;
4077 	kfree(sm_info);
4078 }
4079 
4080 int __init f2fs_create_segment_manager_caches(void)
4081 {
4082 	discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
4083 			sizeof(struct discard_entry));
4084 	if (!discard_entry_slab)
4085 		goto fail;
4086 
4087 	discard_cmd_slab = f2fs_kmem_cache_create("discard_cmd",
4088 			sizeof(struct discard_cmd));
4089 	if (!discard_cmd_slab)
4090 		goto destroy_discard_entry;
4091 
4092 	sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
4093 			sizeof(struct sit_entry_set));
4094 	if (!sit_entry_set_slab)
4095 		goto destroy_discard_cmd;
4096 
4097 	inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
4098 			sizeof(struct inmem_pages));
4099 	if (!inmem_entry_slab)
4100 		goto destroy_sit_entry_set;
4101 	return 0;
4102 
4103 destroy_sit_entry_set:
4104 	kmem_cache_destroy(sit_entry_set_slab);
4105 destroy_discard_cmd:
4106 	kmem_cache_destroy(discard_cmd_slab);
4107 destroy_discard_entry:
4108 	kmem_cache_destroy(discard_entry_slab);
4109 fail:
4110 	return -ENOMEM;
4111 }
4112 
4113 void f2fs_destroy_segment_manager_caches(void)
4114 {
4115 	kmem_cache_destroy(sit_entry_set_slab);
4116 	kmem_cache_destroy(discard_cmd_slab);
4117 	kmem_cache_destroy(discard_entry_slab);
4118 	kmem_cache_destroy(inmem_entry_slab);
4119 }
4120