xref: /linux/fs/f2fs/extent_cache.c (revision 995832b2cebe6969d1b42635db698803ee31294d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * f2fs extent cache support
4  *
5  * Copyright (c) 2015 Motorola Mobility
6  * Copyright (c) 2015 Samsung Electronics
7  * Authors: Jaegeuk Kim <jaegeuk@kernel.org>
8  *          Chao Yu <chao2.yu@samsung.com>
9  *
10  * block_age-based extent cache added by:
11  * Copyright (c) 2022 xiaomi Co., Ltd.
12  *             http://www.xiaomi.com/
13  */
14 
15 #include <linux/fs.h>
16 #include <linux/f2fs_fs.h>
17 
18 #include "f2fs.h"
19 #include "node.h"
20 #include <trace/events/f2fs.h>
21 
22 bool sanity_check_extent_cache(struct inode *inode, struct folio *ifolio)
23 {
24 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
25 	struct f2fs_extent *i_ext = &F2FS_INODE(ifolio)->i_ext;
26 	struct extent_info ei;
27 	int devi;
28 
29 	get_read_extent_info(&ei, i_ext);
30 
31 	if (!ei.len)
32 		return true;
33 
34 	if (!f2fs_is_valid_blkaddr(sbi, ei.blk, DATA_GENERIC_ENHANCE) ||
35 	    !f2fs_is_valid_blkaddr(sbi, ei.blk + ei.len - 1,
36 					DATA_GENERIC_ENHANCE)) {
37 		f2fs_warn(sbi, "%s: inode (ino=%llx) extent info [%u, %u, %u] is incorrect, run fsck to fix",
38 			  __func__, inode->i_ino,
39 			  ei.blk, ei.fofs, ei.len);
40 		return false;
41 	}
42 
43 	if (!IS_DEVICE_ALIASING(inode))
44 		return true;
45 
46 	for (devi = 0; devi < sbi->s_ndevs; devi++) {
47 		if (FDEV(devi).start_blk != ei.blk ||
48 				FDEV(devi).end_blk != ei.blk + ei.len - 1)
49 			continue;
50 
51 		if (devi == 0) {
52 			f2fs_warn(sbi,
53 			    "%s: inode (ino=%llx) is an alias of meta device",
54 			    __func__, inode->i_ino);
55 			return false;
56 		}
57 
58 		if (bdev_is_zoned(FDEV(devi).bdev)) {
59 			f2fs_warn(sbi,
60 			    "%s: device alias inode (ino=%llx)'s extent info "
61 			    "[%u, %u, %u] maps to zoned block device",
62 			    __func__, inode->i_ino, ei.blk, ei.fofs, ei.len);
63 			return false;
64 		}
65 		return true;
66 	}
67 
68 	f2fs_warn(sbi, "%s: device alias inode (ino=%llx)'s extent info "
69 			"[%u, %u, %u] is inconsistent w/ any devices",
70 			__func__, inode->i_ino, ei.blk, ei.fofs, ei.len);
71 	return false;
72 }
73 
74 static void __set_extent_info(struct extent_info *ei,
75 				unsigned int fofs, unsigned int len,
76 				block_t blk, bool keep_clen,
77 				unsigned long age, unsigned long last_blocks,
78 				enum extent_type type)
79 {
80 	ei->fofs = fofs;
81 	ei->len = len;
82 
83 	if (type == EX_READ) {
84 		ei->blk = blk;
85 		if (keep_clen)
86 			return;
87 #ifdef CONFIG_F2FS_FS_COMPRESSION
88 		ei->c_len = 0;
89 #endif
90 	} else if (type == EX_BLOCK_AGE) {
91 		ei->age = age;
92 		ei->last_blocks = last_blocks;
93 	}
94 }
95 
96 static bool __init_may_extent_tree(struct inode *inode, enum extent_type type)
97 {
98 	if (type == EX_READ)
99 		return test_opt(F2FS_I_SB(inode), READ_EXTENT_CACHE) &&
100 			S_ISREG(inode->i_mode);
101 	if (type == EX_BLOCK_AGE)
102 		return test_opt(F2FS_I_SB(inode), AGE_EXTENT_CACHE) &&
103 			(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode));
104 	return false;
105 }
106 
107 static bool __may_extent_tree(struct inode *inode, enum extent_type type)
108 {
109 	if (IS_DEVICE_ALIASING(inode) && type == EX_READ)
110 		return true;
111 
112 	/*
113 	 * for recovered files during mount do not create extents
114 	 * if shrinker is not registered.
115 	 */
116 	if (list_empty(&F2FS_I_SB(inode)->s_list))
117 		return false;
118 
119 	if (!__init_may_extent_tree(inode, type))
120 		return false;
121 
122 	if (type == EX_READ) {
123 		if (is_inode_flag_set(inode, FI_NO_EXTENT))
124 			return false;
125 		if (is_inode_flag_set(inode, FI_COMPRESSED_FILE) &&
126 				 !f2fs_sb_has_readonly(F2FS_I_SB(inode)))
127 			return false;
128 	} else if (type == EX_BLOCK_AGE) {
129 		if (is_inode_flag_set(inode, FI_COMPRESSED_FILE))
130 			return false;
131 		if (file_is_cold(inode))
132 			return false;
133 	}
134 	return true;
135 }
136 
137 static void __try_update_largest_extent(struct extent_tree *et,
138 						struct extent_node *en)
139 {
140 	if (et->type != EX_READ)
141 		return;
142 	if (en->ei.len <= et->largest.len)
143 		return;
144 
145 	et->largest = en->ei;
146 	et->largest_updated = true;
147 }
148 
149 static bool __is_extent_mergeable(struct extent_info *back,
150 		struct extent_info *front, enum extent_type type)
151 {
152 	if (type == EX_READ) {
153 #ifdef CONFIG_F2FS_FS_COMPRESSION
154 		if (back->c_len && back->len != back->c_len)
155 			return false;
156 		if (front->c_len && front->len != front->c_len)
157 			return false;
158 #endif
159 		return (back->fofs + back->len == front->fofs &&
160 				back->blk + back->len == front->blk);
161 	} else if (type == EX_BLOCK_AGE) {
162 		return (back->fofs + back->len == front->fofs &&
163 			abs(back->age - front->age) <= SAME_AGE_REGION &&
164 			abs(back->last_blocks - front->last_blocks) <=
165 							SAME_AGE_REGION);
166 	}
167 	return false;
168 }
169 
170 static bool __is_back_mergeable(struct extent_info *cur,
171 		struct extent_info *back, enum extent_type type)
172 {
173 	return __is_extent_mergeable(back, cur, type);
174 }
175 
176 static bool __is_front_mergeable(struct extent_info *cur,
177 		struct extent_info *front, enum extent_type type)
178 {
179 	return __is_extent_mergeable(cur, front, type);
180 }
181 
182 static struct extent_node *__lookup_extent_node(struct rb_root_cached *root,
183 			struct extent_node *cached_en, unsigned int fofs)
184 {
185 	struct rb_node *node = root->rb_root.rb_node;
186 	struct extent_node *en;
187 
188 	/* check a cached entry */
189 	if (cached_en && cached_en->ei.fofs <= fofs &&
190 			cached_en->ei.fofs + cached_en->ei.len > fofs)
191 		return cached_en;
192 
193 	/* check rb_tree */
194 	while (node) {
195 		en = rb_entry(node, struct extent_node, rb_node);
196 
197 		if (fofs < en->ei.fofs)
198 			node = node->rb_left;
199 		else if (fofs >= en->ei.fofs + en->ei.len)
200 			node = node->rb_right;
201 		else
202 			return en;
203 	}
204 	return NULL;
205 }
206 
207 /*
208  * lookup rb entry in position of @fofs in rb-tree,
209  * if hit, return the entry, otherwise, return NULL
210  * @prev_ex: extent before fofs
211  * @next_ex: extent after fofs
212  * @insert_p: insert point for new extent at fofs
213  * in order to simplify the insertion after.
214  * tree must stay unchanged between lookup and insertion.
215  */
216 static struct extent_node *__lookup_extent_node_ret(struct rb_root_cached *root,
217 				struct extent_node *cached_en,
218 				unsigned int fofs,
219 				struct extent_node **prev_entry,
220 				struct extent_node **next_entry,
221 				struct rb_node ***insert_p,
222 				struct rb_node **insert_parent,
223 				bool *leftmost)
224 {
225 	struct rb_node **pnode = &root->rb_root.rb_node;
226 	struct rb_node *parent = NULL, *tmp_node;
227 	struct extent_node *en = cached_en;
228 
229 	*insert_p = NULL;
230 	*insert_parent = NULL;
231 	*prev_entry = NULL;
232 	*next_entry = NULL;
233 
234 	if (RB_EMPTY_ROOT(&root->rb_root))
235 		return NULL;
236 
237 	if (en && en->ei.fofs <= fofs && en->ei.fofs + en->ei.len > fofs)
238 		goto lookup_neighbors;
239 
240 	*leftmost = true;
241 
242 	while (*pnode) {
243 		parent = *pnode;
244 		en = rb_entry(*pnode, struct extent_node, rb_node);
245 
246 		if (fofs < en->ei.fofs) {
247 			pnode = &(*pnode)->rb_left;
248 		} else if (fofs >= en->ei.fofs + en->ei.len) {
249 			pnode = &(*pnode)->rb_right;
250 			*leftmost = false;
251 		} else {
252 			goto lookup_neighbors;
253 		}
254 	}
255 
256 	*insert_p = pnode;
257 	*insert_parent = parent;
258 
259 	en = rb_entry(parent, struct extent_node, rb_node);
260 	tmp_node = parent;
261 	if (parent && fofs > en->ei.fofs)
262 		tmp_node = rb_next(parent);
263 	*next_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);
264 
265 	tmp_node = parent;
266 	if (parent && fofs < en->ei.fofs)
267 		tmp_node = rb_prev(parent);
268 	*prev_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);
269 	return NULL;
270 
271 lookup_neighbors:
272 	if (fofs == en->ei.fofs) {
273 		/* lookup prev node for merging backward later */
274 		tmp_node = rb_prev(&en->rb_node);
275 		*prev_entry = rb_entry_safe(tmp_node,
276 					struct extent_node, rb_node);
277 	}
278 	if (fofs == en->ei.fofs + en->ei.len - 1) {
279 		/* lookup next node for merging frontward later */
280 		tmp_node = rb_next(&en->rb_node);
281 		*next_entry = rb_entry_safe(tmp_node,
282 					struct extent_node, rb_node);
283 	}
284 	return en;
285 }
286 
287 static struct kmem_cache *extent_tree_slab;
288 static struct kmem_cache *extent_node_slab;
289 
290 static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
291 				struct extent_tree *et, struct extent_info *ei,
292 				struct rb_node *parent, struct rb_node **p,
293 				bool leftmost)
294 {
295 	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
296 	struct extent_node *en;
297 
298 	en = f2fs_kmem_cache_alloc(extent_node_slab, GFP_ATOMIC, false, sbi);
299 	if (!en)
300 		return NULL;
301 
302 	en->ei = *ei;
303 	INIT_LIST_HEAD(&en->list);
304 	en->et = et;
305 
306 	rb_link_node(&en->rb_node, parent, p);
307 	rb_insert_color_cached(&en->rb_node, &et->root, leftmost);
308 	atomic_inc(&et->node_cnt);
309 	atomic_inc(&eti->total_ext_node);
310 	return en;
311 }
312 
313 static void __detach_extent_node(struct f2fs_sb_info *sbi,
314 				struct extent_tree *et, struct extent_node *en)
315 {
316 	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
317 
318 	rb_erase_cached(&en->rb_node, &et->root);
319 	atomic_dec(&et->node_cnt);
320 	atomic_dec(&eti->total_ext_node);
321 
322 	if (et->cached_en == en)
323 		et->cached_en = NULL;
324 	kmem_cache_free(extent_node_slab, en);
325 }
326 
327 /*
328  * Flow to release an extent_node:
329  * 1. list_del_init
330  * 2. __detach_extent_node
331  * 3. kmem_cache_free.
332  */
333 static void __release_extent_node(struct f2fs_sb_info *sbi,
334 			struct extent_tree *et, struct extent_node *en)
335 {
336 	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
337 
338 	spin_lock(&eti->extent_lock);
339 	f2fs_bug_on(sbi, list_empty(&en->list));
340 	list_del_init(&en->list);
341 	spin_unlock(&eti->extent_lock);
342 
343 	__detach_extent_node(sbi, et, en);
344 }
345 
346 static struct extent_tree *__grab_extent_tree(struct inode *inode,
347 						enum extent_type type)
348 {
349 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
350 	struct extent_tree_info *eti = &sbi->extent_tree[type];
351 	struct extent_tree *et;
352 	nid_t ino = inode->i_ino;
353 
354 	mutex_lock(&eti->extent_tree_lock);
355 	et = radix_tree_lookup(&eti->extent_tree_root, ino);
356 	if (!et) {
357 		et = f2fs_kmem_cache_alloc(extent_tree_slab,
358 					GFP_NOFS, true, NULL);
359 		f2fs_radix_tree_insert(&eti->extent_tree_root, ino, et);
360 		memset(et, 0, sizeof(struct extent_tree));
361 		et->ino = ino;
362 		et->type = type;
363 		et->root = RB_ROOT_CACHED;
364 		et->cached_en = NULL;
365 		rwlock_init(&et->lock);
366 		INIT_LIST_HEAD(&et->list);
367 		atomic_set(&et->node_cnt, 0);
368 		atomic_inc(&eti->total_ext_tree);
369 	} else {
370 		atomic_dec(&eti->total_zombie_tree);
371 		list_del_init(&et->list);
372 	}
373 	mutex_unlock(&eti->extent_tree_lock);
374 
375 	/* never died until evict_inode */
376 	F2FS_I(inode)->extent_tree[type] = et;
377 
378 	return et;
379 }
380 
381 static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
382 				struct extent_tree *et, unsigned int nr_shrink)
383 {
384 	struct rb_node *node, *next;
385 	struct extent_node *en;
386 	unsigned int count;
387 
388 	node = rb_first_cached(&et->root);
389 
390 	for (count = 0; node && count < nr_shrink; count++) {
391 		next = rb_next(node);
392 		en = rb_entry(node, struct extent_node, rb_node);
393 		__release_extent_node(sbi, et, en);
394 		node = next;
395 	}
396 
397 	return count;
398 }
399 
400 static void __drop_largest_extent(struct extent_tree *et,
401 					pgoff_t fofs, unsigned int len)
402 {
403 	if (fofs < (pgoff_t)et->largest.fofs + et->largest.len &&
404 			fofs + len > et->largest.fofs) {
405 		et->largest.len = 0;
406 		et->largest_updated = true;
407 	}
408 }
409 
410 void f2fs_init_read_extent_tree(struct inode *inode, struct folio *ifolio)
411 {
412 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
413 	struct extent_tree_info *eti = &sbi->extent_tree[EX_READ];
414 	struct f2fs_extent *i_ext = &F2FS_INODE(ifolio)->i_ext;
415 	struct extent_tree *et;
416 	struct extent_node *en;
417 	struct extent_info ei = {0};
418 
419 	if (!__may_extent_tree(inode, EX_READ)) {
420 		/* drop largest read extent */
421 		if (i_ext->len) {
422 			f2fs_folio_wait_writeback(ifolio, NODE, true, true);
423 			i_ext->len = 0;
424 			folio_mark_dirty(ifolio);
425 		}
426 		set_inode_flag(inode, FI_NO_EXTENT);
427 		return;
428 	}
429 
430 	et = __grab_extent_tree(inode, EX_READ);
431 
432 	get_read_extent_info(&ei, i_ext);
433 
434 	write_lock(&et->lock);
435 	if (atomic_read(&et->node_cnt) || !ei.len)
436 		goto skip;
437 
438 	if (IS_DEVICE_ALIASING(inode)) {
439 		et->largest = ei;
440 		goto skip;
441 	}
442 
443 	en = __attach_extent_node(sbi, et, &ei, NULL,
444 				&et->root.rb_root.rb_node, true);
445 	if (en) {
446 		et->largest = en->ei;
447 		et->cached_en = en;
448 
449 		spin_lock(&eti->extent_lock);
450 		list_add_tail(&en->list, &eti->extent_list);
451 		spin_unlock(&eti->extent_lock);
452 	}
453 skip:
454 	/* Let's drop, if checkpoint got corrupted. */
455 	if (f2fs_cp_error(sbi)) {
456 		et->largest.len = 0;
457 		et->largest_updated = true;
458 	}
459 	write_unlock(&et->lock);
460 }
461 
462 void f2fs_init_age_extent_tree(struct inode *inode)
463 {
464 	if (!__init_may_extent_tree(inode, EX_BLOCK_AGE))
465 		return;
466 	__grab_extent_tree(inode, EX_BLOCK_AGE);
467 }
468 
469 void f2fs_init_extent_tree(struct inode *inode)
470 {
471 	/* initialize read cache */
472 	if (__init_may_extent_tree(inode, EX_READ))
473 		__grab_extent_tree(inode, EX_READ);
474 
475 	/* initialize block age cache */
476 	if (__init_may_extent_tree(inode, EX_BLOCK_AGE))
477 		__grab_extent_tree(inode, EX_BLOCK_AGE);
478 }
479 
480 static bool __lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
481 			struct extent_info *ei, enum extent_type type)
482 {
483 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
484 	struct extent_tree_info *eti = &sbi->extent_tree[type];
485 	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
486 	struct extent_node *en;
487 	bool ret = false;
488 
489 	if (!et)
490 		return false;
491 
492 	trace_f2fs_lookup_extent_tree_start(inode, pgofs, type);
493 
494 	read_lock(&et->lock);
495 
496 	if (type == EX_READ &&
497 			et->largest.fofs <= pgofs &&
498 			(pgoff_t)et->largest.fofs + et->largest.len > pgofs) {
499 		*ei = et->largest;
500 		ret = true;
501 		stat_inc_largest_node_hit(sbi);
502 		goto out;
503 	}
504 
505 	if (IS_DEVICE_ALIASING(inode)) {
506 		ret = false;
507 		goto out;
508 	}
509 
510 	en = __lookup_extent_node(&et->root, et->cached_en, pgofs);
511 	if (!en)
512 		goto out;
513 
514 	if (en == et->cached_en)
515 		stat_inc_cached_node_hit(sbi, type);
516 	else
517 		stat_inc_rbtree_node_hit(sbi, type);
518 
519 	*ei = en->ei;
520 	spin_lock(&eti->extent_lock);
521 	if (!list_empty(&en->list)) {
522 		list_move_tail(&en->list, &eti->extent_list);
523 		et->cached_en = en;
524 	}
525 	spin_unlock(&eti->extent_lock);
526 	ret = true;
527 out:
528 	stat_inc_total_hit(sbi, type);
529 	read_unlock(&et->lock);
530 
531 	if (type == EX_READ)
532 		trace_f2fs_lookup_read_extent_tree_end(inode, pgofs, ei);
533 	else if (type == EX_BLOCK_AGE)
534 		trace_f2fs_lookup_age_extent_tree_end(inode, pgofs, ei);
535 	return ret;
536 }
537 
538 static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
539 				struct extent_tree *et, struct extent_info *ei,
540 				struct extent_node *prev_ex,
541 				struct extent_node *next_ex)
542 {
543 	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
544 	struct extent_node *en = NULL;
545 
546 	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei, et->type)) {
547 		prev_ex->ei.len += ei->len;
548 		ei = &prev_ex->ei;
549 		en = prev_ex;
550 	}
551 
552 	if (next_ex && __is_front_mergeable(ei, &next_ex->ei, et->type)) {
553 		next_ex->ei.fofs = ei->fofs;
554 		next_ex->ei.len += ei->len;
555 		if (et->type == EX_READ)
556 			next_ex->ei.blk = ei->blk;
557 		if (en)
558 			__release_extent_node(sbi, et, prev_ex);
559 
560 		en = next_ex;
561 	}
562 
563 	if (!en)
564 		return NULL;
565 
566 	__try_update_largest_extent(et, en);
567 
568 	spin_lock(&eti->extent_lock);
569 	if (!list_empty(&en->list)) {
570 		list_move_tail(&en->list, &eti->extent_list);
571 		et->cached_en = en;
572 	}
573 	spin_unlock(&eti->extent_lock);
574 	return en;
575 }
576 
577 static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
578 				struct extent_tree *et, struct extent_info *ei,
579 				struct rb_node **insert_p,
580 				struct rb_node *insert_parent,
581 				bool leftmost)
582 {
583 	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
584 	struct rb_node **p = &et->root.rb_root.rb_node;
585 	struct rb_node *parent = NULL;
586 	struct extent_node *en = NULL;
587 
588 	if (insert_p && insert_parent) {
589 		parent = insert_parent;
590 		p = insert_p;
591 		goto do_insert;
592 	}
593 
594 	leftmost = true;
595 
596 	/* look up extent_node in the rb tree */
597 	while (*p) {
598 		parent = *p;
599 		en = rb_entry(parent, struct extent_node, rb_node);
600 
601 		if (ei->fofs < en->ei.fofs) {
602 			p = &(*p)->rb_left;
603 		} else if (ei->fofs >= en->ei.fofs + en->ei.len) {
604 			p = &(*p)->rb_right;
605 			leftmost = false;
606 		} else {
607 			f2fs_err_ratelimited(sbi, "%s: corrupted extent, type: %d, "
608 				"extent node in rb tree [%u, %u, %u], age [%llu, %llu], "
609 				"extent node to insert [%u, %u, %u], age [%llu, %llu]",
610 				__func__, et->type, en->ei.fofs, en->ei.blk, en->ei.len, en->ei.age,
611 				en->ei.last_blocks, ei->fofs, ei->blk, ei->len, ei->age, ei->last_blocks);
612 			f2fs_bug_on(sbi, 1);
613 			return NULL;
614 		}
615 	}
616 
617 do_insert:
618 	en = __attach_extent_node(sbi, et, ei, parent, p, leftmost);
619 	if (!en)
620 		return NULL;
621 
622 	__try_update_largest_extent(et, en);
623 
624 	/* update in global extent list */
625 	spin_lock(&eti->extent_lock);
626 	list_add_tail(&en->list, &eti->extent_list);
627 	et->cached_en = en;
628 	spin_unlock(&eti->extent_lock);
629 	return en;
630 }
631 
632 static unsigned int __destroy_extent_node(struct inode *inode,
633 					enum extent_type type)
634 {
635 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
636 	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
637 	unsigned int nr_shrink = type == EX_READ ?
638 				READ_EXTENT_CACHE_SHRINK_NUMBER :
639 				AGE_EXTENT_CACHE_SHRINK_NUMBER;
640 	unsigned int node_cnt = 0;
641 
642 	if (!et || !atomic_read(&et->node_cnt))
643 		return 0;
644 
645 	while (atomic_read(&et->node_cnt)) {
646 		write_lock(&et->lock);
647 		node_cnt += __free_extent_tree(sbi, et, nr_shrink);
648 		write_unlock(&et->lock);
649 	}
650 
651 	return node_cnt;
652 }
653 
654 static void __update_extent_tree_range(struct inode *inode,
655 			struct extent_info *tei, enum extent_type type)
656 {
657 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
658 	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
659 	struct extent_node *en = NULL, *en1 = NULL;
660 	struct extent_node *prev_en = NULL, *next_en = NULL;
661 	struct extent_info ei, dei, prev;
662 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
663 	unsigned int fofs = tei->fofs, len = tei->len;
664 	unsigned int end = fofs + len;
665 	bool updated = false;
666 	bool leftmost = false;
667 
668 	if (!et)
669 		return;
670 
671 	if (unlikely(len == 0)) {
672 		f2fs_err_ratelimited(sbi, "%s: extent len is zero, type: %d, "
673 			"extent [%u, %u, %u], age [%llu, %llu]",
674 			__func__, type, tei->fofs, tei->blk, tei->len,
675 			tei->age, tei->last_blocks);
676 		f2fs_bug_on(sbi, 1);
677 		return;
678 	}
679 
680 	if (type == EX_READ)
681 		trace_f2fs_update_read_extent_tree_range(inode, fofs, len,
682 						tei->blk, 0);
683 	else if (type == EX_BLOCK_AGE)
684 		trace_f2fs_update_age_extent_tree_range(inode, fofs, len,
685 						tei->age, tei->last_blocks);
686 
687 	write_lock(&et->lock);
688 
689 	if (type == EX_READ) {
690 		if (is_inode_flag_set(inode, FI_NO_EXTENT)) {
691 			write_unlock(&et->lock);
692 			return;
693 		}
694 
695 		prev = et->largest;
696 		dei.len = 0;
697 
698 		/*
699 		 * drop largest extent before lookup, in case it's already
700 		 * been shrunk from extent tree
701 		 */
702 		__drop_largest_extent(et, fofs, len);
703 	}
704 
705 	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
706 	en = __lookup_extent_node_ret(&et->root,
707 					et->cached_en, fofs,
708 					&prev_en, &next_en,
709 					&insert_p, &insert_parent,
710 					&leftmost);
711 	if (!en)
712 		en = next_en;
713 
714 	/* 2. invalidate all extent nodes in range [fofs, fofs + len - 1] */
715 	while (en && en->ei.fofs < end) {
716 		unsigned int org_end;
717 		int parts = 0;	/* # of parts current extent split into */
718 
719 		next_en = en1 = NULL;
720 
721 		dei = en->ei;
722 		org_end = dei.fofs + dei.len;
723 		f2fs_bug_on(sbi, fofs >= org_end);
724 
725 		if (fofs > dei.fofs && (type != EX_READ ||
726 				fofs - dei.fofs >= F2FS_MIN_EXTENT_LEN)) {
727 			en->ei.len = fofs - en->ei.fofs;
728 			prev_en = en;
729 			parts = 1;
730 		}
731 
732 		if (end < org_end && (type != EX_READ ||
733 			(org_end - end >= F2FS_MIN_EXTENT_LEN &&
734 			atomic_read(&et->node_cnt) <
735 					sbi->max_read_extent_count))) {
736 			if (parts) {
737 				__set_extent_info(&ei,
738 					end, org_end - end,
739 					end - dei.fofs + dei.blk, false,
740 					dei.age, dei.last_blocks,
741 					type);
742 				en1 = __insert_extent_tree(sbi, et, &ei,
743 							NULL, NULL, true);
744 				next_en = en1;
745 			} else {
746 				__set_extent_info(&en->ei,
747 					end, en->ei.len - (end - dei.fofs),
748 					en->ei.blk + (end - dei.fofs), true,
749 					dei.age, dei.last_blocks,
750 					type);
751 				next_en = en;
752 			}
753 			parts++;
754 		}
755 
756 		if (!next_en) {
757 			struct rb_node *node = rb_next(&en->rb_node);
758 
759 			next_en = rb_entry_safe(node, struct extent_node,
760 						rb_node);
761 		}
762 
763 		if (parts)
764 			__try_update_largest_extent(et, en);
765 		else
766 			__release_extent_node(sbi, et, en);
767 
768 		/*
769 		 * if original extent is split into zero or two parts, extent
770 		 * tree has been altered by deletion or insertion, therefore
771 		 * invalidate pointers regard to tree.
772 		 */
773 		if (parts != 1) {
774 			insert_p = NULL;
775 			insert_parent = NULL;
776 		}
777 		en = next_en;
778 	}
779 
780 	if (type == EX_BLOCK_AGE)
781 		goto update_age_extent_cache;
782 
783 	/* 3. update extent in read extent cache */
784 	BUG_ON(type != EX_READ);
785 
786 	if (tei->blk) {
787 		__set_extent_info(&ei, fofs, len, tei->blk, false,
788 				  0, 0, EX_READ);
789 		if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
790 			__insert_extent_tree(sbi, et, &ei,
791 					insert_p, insert_parent, leftmost);
792 
793 		/* give up extent_cache, if split and small updates happen */
794 		if (dei.len >= 1 &&
795 				prev.len < F2FS_MIN_EXTENT_LEN &&
796 				et->largest.len < F2FS_MIN_EXTENT_LEN) {
797 			et->largest.len = 0;
798 			et->largest_updated = true;
799 			set_inode_flag(inode, FI_NO_EXTENT);
800 		}
801 	}
802 
803 	if (et->largest_updated) {
804 		et->largest_updated = false;
805 		updated = true;
806 	}
807 	goto out_read_extent_cache;
808 update_age_extent_cache:
809 	if (tei->last_blocks == F2FS_EXTENT_AGE_INVALID)
810 		goto out_read_extent_cache;
811 
812 	__set_extent_info(&ei, fofs, len, 0, false,
813 			tei->age, tei->last_blocks, EX_BLOCK_AGE);
814 	if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
815 		__insert_extent_tree(sbi, et, &ei,
816 					insert_p, insert_parent, leftmost);
817 out_read_extent_cache:
818 	write_unlock(&et->lock);
819 
820 	if (is_inode_flag_set(inode, FI_NO_EXTENT))
821 		__destroy_extent_node(inode, EX_READ);
822 
823 	if (updated)
824 		f2fs_mark_inode_dirty_sync(inode, true);
825 }
826 
827 #ifdef CONFIG_F2FS_FS_COMPRESSION
828 void f2fs_update_read_extent_tree_range_compressed(struct inode *inode,
829 				pgoff_t fofs, block_t blkaddr, unsigned int llen,
830 				unsigned int c_len)
831 {
832 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
833 	struct extent_tree *et = F2FS_I(inode)->extent_tree[EX_READ];
834 	struct extent_node *en = NULL;
835 	struct extent_node *prev_en = NULL, *next_en = NULL;
836 	struct extent_info ei;
837 	struct rb_node **insert_p = NULL, *insert_parent = NULL;
838 	bool leftmost = false;
839 
840 	trace_f2fs_update_read_extent_tree_range(inode, fofs, llen,
841 						blkaddr, c_len);
842 
843 	/* it is safe here to check FI_NO_EXTENT w/o et->lock in ro image */
844 	if (is_inode_flag_set(inode, FI_NO_EXTENT))
845 		return;
846 
847 	write_lock(&et->lock);
848 
849 	en = __lookup_extent_node_ret(&et->root,
850 					et->cached_en, fofs,
851 					&prev_en, &next_en,
852 					&insert_p, &insert_parent,
853 					&leftmost);
854 	if (en)
855 		goto unlock_out;
856 
857 	__set_extent_info(&ei, fofs, llen, blkaddr, true, 0, 0, EX_READ);
858 	ei.c_len = c_len;
859 
860 	if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
861 		__insert_extent_tree(sbi, et, &ei,
862 				insert_p, insert_parent, leftmost);
863 unlock_out:
864 	write_unlock(&et->lock);
865 }
866 #endif
867 
868 static unsigned long long __calculate_block_age(struct f2fs_sb_info *sbi,
869 						unsigned long long new,
870 						unsigned long long old)
871 {
872 	unsigned int rem_old, rem_new;
873 	unsigned long long res;
874 	unsigned int weight = sbi->last_age_weight;
875 
876 	res = div_u64_rem(new, 100, &rem_new) * (100 - weight)
877 		+ div_u64_rem(old, 100, &rem_old) * weight;
878 
879 	if (rem_new)
880 		res += rem_new * (100 - weight) / 100;
881 	if (rem_old)
882 		res += rem_old * weight / 100;
883 
884 	return res;
885 }
886 
887 /* This returns a new age and allocated blocks in ei */
888 static int __get_new_block_age(struct inode *inode, struct extent_info *ei,
889 						block_t blkaddr)
890 {
891 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
892 	loff_t f_size = i_size_read(inode);
893 	unsigned long long cur_blocks =
894 				atomic64_read(&sbi->allocated_data_blocks);
895 	struct extent_info tei = *ei;	/* only fofs and len are valid */
896 
897 	/*
898 	 * When I/O is not aligned to a PAGE_SIZE, update will happen to the last
899 	 * file block even in seq write. So don't record age for newly last file
900 	 * block here.
901 	 */
902 	if ((f_size >> PAGE_SHIFT) == ei->fofs && f_size & (PAGE_SIZE - 1) &&
903 			blkaddr == NEW_ADDR)
904 		return -EINVAL;
905 
906 	if (__lookup_extent_tree(inode, ei->fofs, &tei, EX_BLOCK_AGE)) {
907 		unsigned long long cur_age;
908 
909 		if (cur_blocks >= tei.last_blocks)
910 			cur_age = cur_blocks - tei.last_blocks;
911 		else
912 			/* allocated_data_blocks overflow */
913 			cur_age = (ULLONG_MAX - 1) - tei.last_blocks + cur_blocks;
914 
915 		if (tei.age)
916 			ei->age = __calculate_block_age(sbi, cur_age, tei.age);
917 		else
918 			ei->age = cur_age;
919 		ei->last_blocks = cur_blocks;
920 		WARN_ON(ei->age > cur_blocks);
921 		return 0;
922 	}
923 
924 	f2fs_bug_on(sbi, blkaddr == NULL_ADDR);
925 
926 	/* the data block was allocated for the first time */
927 	if (blkaddr == NEW_ADDR)
928 		goto out;
929 
930 	if (__is_valid_data_blkaddr(blkaddr) &&
931 	    !f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE))
932 		return -EINVAL;
933 out:
934 	/*
935 	 * init block age with zero, this can happen when the block age extent
936 	 * was reclaimed due to memory constraint or system reboot
937 	 */
938 	ei->age = 0;
939 	ei->last_blocks = cur_blocks;
940 	return 0;
941 }
942 
943 static void __update_extent_cache(struct dnode_of_data *dn, enum extent_type type)
944 {
945 	struct extent_info ei = {};
946 
947 	if (!__may_extent_tree(dn->inode, type))
948 		return;
949 
950 	ei.fofs = f2fs_start_bidx_of_node(ofs_of_node(dn->node_folio), dn->inode) +
951 								dn->ofs_in_node;
952 	ei.len = 1;
953 
954 	if (type == EX_READ) {
955 		if (dn->data_blkaddr == NEW_ADDR)
956 			ei.blk = NULL_ADDR;
957 		else
958 			ei.blk = dn->data_blkaddr;
959 	} else if (type == EX_BLOCK_AGE) {
960 		if (__get_new_block_age(dn->inode, &ei, dn->data_blkaddr))
961 			return;
962 	}
963 	__update_extent_tree_range(dn->inode, &ei, type);
964 }
965 
966 static unsigned int __shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink,
967 					enum extent_type type)
968 {
969 	struct extent_tree_info *eti = &sbi->extent_tree[type];
970 	struct extent_tree *et, *next;
971 	struct extent_node *en;
972 	unsigned int node_cnt = 0, tree_cnt = 0;
973 	int remained;
974 
975 	if (!atomic_read(&eti->total_zombie_tree))
976 		goto free_node;
977 
978 	if (!mutex_trylock(&eti->extent_tree_lock))
979 		goto out;
980 
981 	/* 1. remove unreferenced extent tree */
982 	list_for_each_entry_safe(et, next, &eti->zombie_list, list) {
983 		if (atomic_read(&et->node_cnt)) {
984 			write_lock(&et->lock);
985 			node_cnt += __free_extent_tree(sbi, et,
986 					nr_shrink - node_cnt - tree_cnt);
987 			write_unlock(&et->lock);
988 		}
989 
990 		if (atomic_read(&et->node_cnt))
991 			goto unlock_out;
992 
993 		list_del_init(&et->list);
994 		radix_tree_delete(&eti->extent_tree_root, et->ino);
995 		kmem_cache_free(extent_tree_slab, et);
996 		atomic_dec(&eti->total_ext_tree);
997 		atomic_dec(&eti->total_zombie_tree);
998 		tree_cnt++;
999 
1000 		if (node_cnt + tree_cnt >= nr_shrink)
1001 			goto unlock_out;
1002 		cond_resched();
1003 	}
1004 	mutex_unlock(&eti->extent_tree_lock);
1005 
1006 free_node:
1007 	/* 2. remove LRU extent entries */
1008 	if (!mutex_trylock(&eti->extent_tree_lock))
1009 		goto out;
1010 
1011 	remained = nr_shrink - (node_cnt + tree_cnt);
1012 
1013 	spin_lock(&eti->extent_lock);
1014 	for (; remained > 0; remained--) {
1015 		if (list_empty(&eti->extent_list))
1016 			break;
1017 		en = list_first_entry(&eti->extent_list,
1018 					struct extent_node, list);
1019 		et = en->et;
1020 		if (!write_trylock(&et->lock)) {
1021 			/* refresh this extent node's position in extent list */
1022 			list_move_tail(&en->list, &eti->extent_list);
1023 			continue;
1024 		}
1025 
1026 		list_del_init(&en->list);
1027 		spin_unlock(&eti->extent_lock);
1028 
1029 		__detach_extent_node(sbi, et, en);
1030 
1031 		write_unlock(&et->lock);
1032 		node_cnt++;
1033 		spin_lock(&eti->extent_lock);
1034 	}
1035 	spin_unlock(&eti->extent_lock);
1036 
1037 unlock_out:
1038 	mutex_unlock(&eti->extent_tree_lock);
1039 out:
1040 	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt, type);
1041 
1042 	return node_cnt + tree_cnt;
1043 }
1044 
1045 /* read extent cache operations */
1046 bool f2fs_lookup_read_extent_cache(struct inode *inode, pgoff_t pgofs,
1047 				struct extent_info *ei)
1048 {
1049 	if (!__may_extent_tree(inode, EX_READ))
1050 		return false;
1051 
1052 	return __lookup_extent_tree(inode, pgofs, ei, EX_READ);
1053 }
1054 
1055 bool f2fs_lookup_read_extent_cache_block(struct inode *inode, pgoff_t index,
1056 				block_t *blkaddr)
1057 {
1058 	struct extent_info ei = {};
1059 
1060 	if (!f2fs_lookup_read_extent_cache(inode, index, &ei))
1061 		return false;
1062 	*blkaddr = ei.blk + index - ei.fofs;
1063 	return true;
1064 }
1065 
1066 void f2fs_update_read_extent_cache(struct dnode_of_data *dn)
1067 {
1068 	return __update_extent_cache(dn, EX_READ);
1069 }
1070 
1071 void f2fs_update_read_extent_cache_range(struct dnode_of_data *dn,
1072 				pgoff_t fofs, block_t blkaddr, unsigned int len)
1073 {
1074 	struct extent_info ei = {
1075 		.fofs = fofs,
1076 		.len = len,
1077 		.blk = blkaddr,
1078 	};
1079 
1080 	if (!__may_extent_tree(dn->inode, EX_READ))
1081 		return;
1082 
1083 	__update_extent_tree_range(dn->inode, &ei, EX_READ);
1084 }
1085 
1086 unsigned int f2fs_shrink_read_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
1087 {
1088 	if (!test_opt(sbi, READ_EXTENT_CACHE))
1089 		return 0;
1090 
1091 	return __shrink_extent_tree(sbi, nr_shrink, EX_READ);
1092 }
1093 
1094 /* block age extent cache operations */
1095 bool f2fs_lookup_age_extent_cache(struct inode *inode, pgoff_t pgofs,
1096 				struct extent_info *ei)
1097 {
1098 	if (!__may_extent_tree(inode, EX_BLOCK_AGE))
1099 		return false;
1100 
1101 	return __lookup_extent_tree(inode, pgofs, ei, EX_BLOCK_AGE);
1102 }
1103 
1104 void f2fs_update_age_extent_cache(struct dnode_of_data *dn)
1105 {
1106 	return __update_extent_cache(dn, EX_BLOCK_AGE);
1107 }
1108 
1109 void f2fs_update_age_extent_cache_range(struct dnode_of_data *dn,
1110 				pgoff_t fofs, unsigned int len)
1111 {
1112 	struct extent_info ei = {
1113 		.fofs = fofs,
1114 		.len = len,
1115 		.last_blocks = F2FS_EXTENT_AGE_INVALID,
1116 	};
1117 
1118 	if (!__may_extent_tree(dn->inode, EX_BLOCK_AGE))
1119 		return;
1120 
1121 	__update_extent_tree_range(dn->inode, &ei, EX_BLOCK_AGE);
1122 }
1123 
1124 unsigned int f2fs_shrink_age_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
1125 {
1126 	if (!test_opt(sbi, AGE_EXTENT_CACHE))
1127 		return 0;
1128 
1129 	return __shrink_extent_tree(sbi, nr_shrink, EX_BLOCK_AGE);
1130 }
1131 
1132 void f2fs_destroy_extent_node(struct inode *inode)
1133 {
1134 	__destroy_extent_node(inode, EX_READ);
1135 	__destroy_extent_node(inode, EX_BLOCK_AGE);
1136 }
1137 
1138 static void __drop_extent_tree(struct inode *inode, enum extent_type type)
1139 {
1140 	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
1141 	bool updated = false;
1142 
1143 	if (!__may_extent_tree(inode, type))
1144 		return;
1145 
1146 	write_lock(&et->lock);
1147 	if (type == EX_READ) {
1148 		set_inode_flag(inode, FI_NO_EXTENT);
1149 		if (et->largest.len) {
1150 			et->largest.len = 0;
1151 			updated = true;
1152 		}
1153 	}
1154 	write_unlock(&et->lock);
1155 
1156 	__destroy_extent_node(inode, type);
1157 
1158 	if (updated)
1159 		f2fs_mark_inode_dirty_sync(inode, true);
1160 }
1161 
1162 void f2fs_drop_extent_tree(struct inode *inode)
1163 {
1164 	__drop_extent_tree(inode, EX_READ);
1165 	__drop_extent_tree(inode, EX_BLOCK_AGE);
1166 }
1167 
1168 static void __destroy_extent_tree(struct inode *inode, enum extent_type type)
1169 {
1170 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1171 	struct extent_tree_info *eti = &sbi->extent_tree[type];
1172 	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
1173 	unsigned int node_cnt = 0;
1174 
1175 	if (!et)
1176 		return;
1177 
1178 	if (inode->i_nlink && !is_bad_inode(inode) &&
1179 					atomic_read(&et->node_cnt)) {
1180 		mutex_lock(&eti->extent_tree_lock);
1181 		list_add_tail(&et->list, &eti->zombie_list);
1182 		atomic_inc(&eti->total_zombie_tree);
1183 		mutex_unlock(&eti->extent_tree_lock);
1184 		return;
1185 	}
1186 
1187 	/* free all extent info belong to this extent tree */
1188 	node_cnt = __destroy_extent_node(inode, type);
1189 
1190 	/* delete extent tree entry in radix tree */
1191 	mutex_lock(&eti->extent_tree_lock);
1192 	f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
1193 	radix_tree_delete(&eti->extent_tree_root, inode->i_ino);
1194 	kmem_cache_free(extent_tree_slab, et);
1195 	atomic_dec(&eti->total_ext_tree);
1196 	mutex_unlock(&eti->extent_tree_lock);
1197 
1198 	F2FS_I(inode)->extent_tree[type] = NULL;
1199 
1200 	trace_f2fs_destroy_extent_tree(inode, node_cnt, type);
1201 }
1202 
1203 void f2fs_destroy_extent_tree(struct inode *inode)
1204 {
1205 	__destroy_extent_tree(inode, EX_READ);
1206 	__destroy_extent_tree(inode, EX_BLOCK_AGE);
1207 }
1208 
1209 static void __init_extent_tree_info(struct extent_tree_info *eti)
1210 {
1211 	INIT_RADIX_TREE(&eti->extent_tree_root, GFP_NOIO);
1212 	mutex_init(&eti->extent_tree_lock);
1213 	INIT_LIST_HEAD(&eti->extent_list);
1214 	spin_lock_init(&eti->extent_lock);
1215 	atomic_set(&eti->total_ext_tree, 0);
1216 	INIT_LIST_HEAD(&eti->zombie_list);
1217 	atomic_set(&eti->total_zombie_tree, 0);
1218 	atomic_set(&eti->total_ext_node, 0);
1219 }
1220 
1221 void f2fs_init_extent_cache_info(struct f2fs_sb_info *sbi)
1222 {
1223 	__init_extent_tree_info(&sbi->extent_tree[EX_READ]);
1224 	__init_extent_tree_info(&sbi->extent_tree[EX_BLOCK_AGE]);
1225 
1226 	/* initialize for block age extents */
1227 	atomic64_set(&sbi->allocated_data_blocks, 0);
1228 	sbi->hot_data_age_threshold = DEF_HOT_DATA_AGE_THRESHOLD;
1229 	sbi->warm_data_age_threshold = DEF_WARM_DATA_AGE_THRESHOLD;
1230 	sbi->last_age_weight = LAST_AGE_WEIGHT;
1231 	sbi->max_read_extent_count = DEF_MAX_READ_EXTENT_COUNT;
1232 }
1233 
1234 int __init f2fs_create_extent_cache(void)
1235 {
1236 	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
1237 			sizeof(struct extent_tree));
1238 	if (!extent_tree_slab)
1239 		return -ENOMEM;
1240 	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
1241 			sizeof(struct extent_node));
1242 	if (!extent_node_slab) {
1243 		kmem_cache_destroy(extent_tree_slab);
1244 		return -ENOMEM;
1245 	}
1246 	return 0;
1247 }
1248 
1249 void f2fs_destroy_extent_cache(void)
1250 {
1251 	kmem_cache_destroy(extent_node_slab);
1252 	kmem_cache_destroy(extent_tree_slab);
1253 }
1254