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
22bool sanity_check_extent_cache(struct inode *inode)
23{
24	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
25	struct f2fs_inode_info *fi = F2FS_I(inode);
26	struct extent_tree *et = fi->extent_tree[EX_READ];
27	struct extent_info *ei;
28
29	if (!et)
30		return true;
31
32	ei = &et->largest;
33	if (!ei->len)
34		return true;
35
36	/* Let's drop, if checkpoint got corrupted. */
37	if (is_set_ckpt_flags(sbi, CP_ERROR_FLAG)) {
38		ei->len = 0;
39		et->largest_updated = true;
40		return true;
41	}
42
43	if (!f2fs_is_valid_blkaddr(sbi, ei->blk, DATA_GENERIC_ENHANCE) ||
44	    !f2fs_is_valid_blkaddr(sbi, ei->blk + ei->len - 1,
45					DATA_GENERIC_ENHANCE)) {
46		f2fs_warn(sbi, "%s: inode (ino=%lx) extent info [%u, %u, %u] is incorrect, run fsck to fix",
47			  __func__, inode->i_ino,
48			  ei->blk, ei->fofs, ei->len);
49		return false;
50	}
51	return true;
52}
53
54static void __set_extent_info(struct extent_info *ei,
55				unsigned int fofs, unsigned int len,
56				block_t blk, bool keep_clen,
57				unsigned long age, unsigned long last_blocks,
58				enum extent_type type)
59{
60	ei->fofs = fofs;
61	ei->len = len;
62
63	if (type == EX_READ) {
64		ei->blk = blk;
65		if (keep_clen)
66			return;
67#ifdef CONFIG_F2FS_FS_COMPRESSION
68		ei->c_len = 0;
69#endif
70	} else if (type == EX_BLOCK_AGE) {
71		ei->age = age;
72		ei->last_blocks = last_blocks;
73	}
74}
75
76static bool __init_may_extent_tree(struct inode *inode, enum extent_type type)
77{
78	if (type == EX_READ)
79		return test_opt(F2FS_I_SB(inode), READ_EXTENT_CACHE) &&
80			S_ISREG(inode->i_mode);
81	if (type == EX_BLOCK_AGE)
82		return test_opt(F2FS_I_SB(inode), AGE_EXTENT_CACHE) &&
83			(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode));
84	return false;
85}
86
87static bool __may_extent_tree(struct inode *inode, enum extent_type type)
88{
89	/*
90	 * for recovered files during mount do not create extents
91	 * if shrinker is not registered.
92	 */
93	if (list_empty(&F2FS_I_SB(inode)->s_list))
94		return false;
95
96	if (!__init_may_extent_tree(inode, type))
97		return false;
98
99	if (type == EX_READ) {
100		if (is_inode_flag_set(inode, FI_NO_EXTENT))
101			return false;
102		if (is_inode_flag_set(inode, FI_COMPRESSED_FILE) &&
103				 !f2fs_sb_has_readonly(F2FS_I_SB(inode)))
104			return false;
105	} else if (type == EX_BLOCK_AGE) {
106		if (is_inode_flag_set(inode, FI_COMPRESSED_FILE))
107			return false;
108		if (file_is_cold(inode))
109			return false;
110	}
111	return true;
112}
113
114static void __try_update_largest_extent(struct extent_tree *et,
115						struct extent_node *en)
116{
117	if (et->type != EX_READ)
118		return;
119	if (en->ei.len <= et->largest.len)
120		return;
121
122	et->largest = en->ei;
123	et->largest_updated = true;
124}
125
126static bool __is_extent_mergeable(struct extent_info *back,
127		struct extent_info *front, enum extent_type type)
128{
129	if (type == EX_READ) {
130#ifdef CONFIG_F2FS_FS_COMPRESSION
131		if (back->c_len && back->len != back->c_len)
132			return false;
133		if (front->c_len && front->len != front->c_len)
134			return false;
135#endif
136		return (back->fofs + back->len == front->fofs &&
137				back->blk + back->len == front->blk);
138	} else if (type == EX_BLOCK_AGE) {
139		return (back->fofs + back->len == front->fofs &&
140			abs(back->age - front->age) <= SAME_AGE_REGION &&
141			abs(back->last_blocks - front->last_blocks) <=
142							SAME_AGE_REGION);
143	}
144	return false;
145}
146
147static bool __is_back_mergeable(struct extent_info *cur,
148		struct extent_info *back, enum extent_type type)
149{
150	return __is_extent_mergeable(back, cur, type);
151}
152
153static bool __is_front_mergeable(struct extent_info *cur,
154		struct extent_info *front, enum extent_type type)
155{
156	return __is_extent_mergeable(cur, front, type);
157}
158
159static struct extent_node *__lookup_extent_node(struct rb_root_cached *root,
160			struct extent_node *cached_en, unsigned int fofs)
161{
162	struct rb_node *node = root->rb_root.rb_node;
163	struct extent_node *en;
164
165	/* check a cached entry */
166	if (cached_en && cached_en->ei.fofs <= fofs &&
167			cached_en->ei.fofs + cached_en->ei.len > fofs)
168		return cached_en;
169
170	/* check rb_tree */
171	while (node) {
172		en = rb_entry(node, struct extent_node, rb_node);
173
174		if (fofs < en->ei.fofs)
175			node = node->rb_left;
176		else if (fofs >= en->ei.fofs + en->ei.len)
177			node = node->rb_right;
178		else
179			return en;
180	}
181	return NULL;
182}
183
184/*
185 * lookup rb entry in position of @fofs in rb-tree,
186 * if hit, return the entry, otherwise, return NULL
187 * @prev_ex: extent before fofs
188 * @next_ex: extent after fofs
189 * @insert_p: insert point for new extent at fofs
190 * in order to simplify the insertion after.
191 * tree must stay unchanged between lookup and insertion.
192 */
193static struct extent_node *__lookup_extent_node_ret(struct rb_root_cached *root,
194				struct extent_node *cached_en,
195				unsigned int fofs,
196				struct extent_node **prev_entry,
197				struct extent_node **next_entry,
198				struct rb_node ***insert_p,
199				struct rb_node **insert_parent,
200				bool *leftmost)
201{
202	struct rb_node **pnode = &root->rb_root.rb_node;
203	struct rb_node *parent = NULL, *tmp_node;
204	struct extent_node *en = cached_en;
205
206	*insert_p = NULL;
207	*insert_parent = NULL;
208	*prev_entry = NULL;
209	*next_entry = NULL;
210
211	if (RB_EMPTY_ROOT(&root->rb_root))
212		return NULL;
213
214	if (en && en->ei.fofs <= fofs && en->ei.fofs + en->ei.len > fofs)
215		goto lookup_neighbors;
216
217	*leftmost = true;
218
219	while (*pnode) {
220		parent = *pnode;
221		en = rb_entry(*pnode, struct extent_node, rb_node);
222
223		if (fofs < en->ei.fofs) {
224			pnode = &(*pnode)->rb_left;
225		} else if (fofs >= en->ei.fofs + en->ei.len) {
226			pnode = &(*pnode)->rb_right;
227			*leftmost = false;
228		} else {
229			goto lookup_neighbors;
230		}
231	}
232
233	*insert_p = pnode;
234	*insert_parent = parent;
235
236	en = rb_entry(parent, struct extent_node, rb_node);
237	tmp_node = parent;
238	if (parent && fofs > en->ei.fofs)
239		tmp_node = rb_next(parent);
240	*next_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);
241
242	tmp_node = parent;
243	if (parent && fofs < en->ei.fofs)
244		tmp_node = rb_prev(parent);
245	*prev_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);
246	return NULL;
247
248lookup_neighbors:
249	if (fofs == en->ei.fofs) {
250		/* lookup prev node for merging backward later */
251		tmp_node = rb_prev(&en->rb_node);
252		*prev_entry = rb_entry_safe(tmp_node,
253					struct extent_node, rb_node);
254	}
255	if (fofs == en->ei.fofs + en->ei.len - 1) {
256		/* lookup next node for merging frontward later */
257		tmp_node = rb_next(&en->rb_node);
258		*next_entry = rb_entry_safe(tmp_node,
259					struct extent_node, rb_node);
260	}
261	return en;
262}
263
264static struct kmem_cache *extent_tree_slab;
265static struct kmem_cache *extent_node_slab;
266
267static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
268				struct extent_tree *et, struct extent_info *ei,
269				struct rb_node *parent, struct rb_node **p,
270				bool leftmost)
271{
272	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
273	struct extent_node *en;
274
275	en = f2fs_kmem_cache_alloc(extent_node_slab, GFP_ATOMIC, false, sbi);
276	if (!en)
277		return NULL;
278
279	en->ei = *ei;
280	INIT_LIST_HEAD(&en->list);
281	en->et = et;
282
283	rb_link_node(&en->rb_node, parent, p);
284	rb_insert_color_cached(&en->rb_node, &et->root, leftmost);
285	atomic_inc(&et->node_cnt);
286	atomic_inc(&eti->total_ext_node);
287	return en;
288}
289
290static void __detach_extent_node(struct f2fs_sb_info *sbi,
291				struct extent_tree *et, struct extent_node *en)
292{
293	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
294
295	rb_erase_cached(&en->rb_node, &et->root);
296	atomic_dec(&et->node_cnt);
297	atomic_dec(&eti->total_ext_node);
298
299	if (et->cached_en == en)
300		et->cached_en = NULL;
301	kmem_cache_free(extent_node_slab, en);
302}
303
304/*
305 * Flow to release an extent_node:
306 * 1. list_del_init
307 * 2. __detach_extent_node
308 * 3. kmem_cache_free.
309 */
310static void __release_extent_node(struct f2fs_sb_info *sbi,
311			struct extent_tree *et, struct extent_node *en)
312{
313	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
314
315	spin_lock(&eti->extent_lock);
316	f2fs_bug_on(sbi, list_empty(&en->list));
317	list_del_init(&en->list);
318	spin_unlock(&eti->extent_lock);
319
320	__detach_extent_node(sbi, et, en);
321}
322
323static struct extent_tree *__grab_extent_tree(struct inode *inode,
324						enum extent_type type)
325{
326	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
327	struct extent_tree_info *eti = &sbi->extent_tree[type];
328	struct extent_tree *et;
329	nid_t ino = inode->i_ino;
330
331	mutex_lock(&eti->extent_tree_lock);
332	et = radix_tree_lookup(&eti->extent_tree_root, ino);
333	if (!et) {
334		et = f2fs_kmem_cache_alloc(extent_tree_slab,
335					GFP_NOFS, true, NULL);
336		f2fs_radix_tree_insert(&eti->extent_tree_root, ino, et);
337		memset(et, 0, sizeof(struct extent_tree));
338		et->ino = ino;
339		et->type = type;
340		et->root = RB_ROOT_CACHED;
341		et->cached_en = NULL;
342		rwlock_init(&et->lock);
343		INIT_LIST_HEAD(&et->list);
344		atomic_set(&et->node_cnt, 0);
345		atomic_inc(&eti->total_ext_tree);
346	} else {
347		atomic_dec(&eti->total_zombie_tree);
348		list_del_init(&et->list);
349	}
350	mutex_unlock(&eti->extent_tree_lock);
351
352	/* never died until evict_inode */
353	F2FS_I(inode)->extent_tree[type] = et;
354
355	return et;
356}
357
358static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
359					struct extent_tree *et)
360{
361	struct rb_node *node, *next;
362	struct extent_node *en;
363	unsigned int count = atomic_read(&et->node_cnt);
364
365	node = rb_first_cached(&et->root);
366	while (node) {
367		next = rb_next(node);
368		en = rb_entry(node, struct extent_node, rb_node);
369		__release_extent_node(sbi, et, en);
370		node = next;
371	}
372
373	return count - atomic_read(&et->node_cnt);
374}
375
376static void __drop_largest_extent(struct extent_tree *et,
377					pgoff_t fofs, unsigned int len)
378{
379	if (fofs < et->largest.fofs + et->largest.len &&
380			fofs + len > et->largest.fofs) {
381		et->largest.len = 0;
382		et->largest_updated = true;
383	}
384}
385
386void f2fs_init_read_extent_tree(struct inode *inode, struct page *ipage)
387{
388	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
389	struct extent_tree_info *eti = &sbi->extent_tree[EX_READ];
390	struct f2fs_extent *i_ext = &F2FS_INODE(ipage)->i_ext;
391	struct extent_tree *et;
392	struct extent_node *en;
393	struct extent_info ei;
394
395	if (!__may_extent_tree(inode, EX_READ)) {
396		/* drop largest read extent */
397		if (i_ext && i_ext->len) {
398			f2fs_wait_on_page_writeback(ipage, NODE, true, true);
399			i_ext->len = 0;
400			set_page_dirty(ipage);
401		}
402		goto out;
403	}
404
405	et = __grab_extent_tree(inode, EX_READ);
406
407	if (!i_ext || !i_ext->len)
408		goto out;
409
410	get_read_extent_info(&ei, i_ext);
411
412	write_lock(&et->lock);
413	if (atomic_read(&et->node_cnt))
414		goto unlock_out;
415
416	en = __attach_extent_node(sbi, et, &ei, NULL,
417				&et->root.rb_root.rb_node, true);
418	if (en) {
419		et->largest = en->ei;
420		et->cached_en = en;
421
422		spin_lock(&eti->extent_lock);
423		list_add_tail(&en->list, &eti->extent_list);
424		spin_unlock(&eti->extent_lock);
425	}
426unlock_out:
427	write_unlock(&et->lock);
428out:
429	if (!F2FS_I(inode)->extent_tree[EX_READ])
430		set_inode_flag(inode, FI_NO_EXTENT);
431}
432
433void f2fs_init_age_extent_tree(struct inode *inode)
434{
435	if (!__init_may_extent_tree(inode, EX_BLOCK_AGE))
436		return;
437	__grab_extent_tree(inode, EX_BLOCK_AGE);
438}
439
440void f2fs_init_extent_tree(struct inode *inode)
441{
442	/* initialize read cache */
443	if (__init_may_extent_tree(inode, EX_READ))
444		__grab_extent_tree(inode, EX_READ);
445
446	/* initialize block age cache */
447	if (__init_may_extent_tree(inode, EX_BLOCK_AGE))
448		__grab_extent_tree(inode, EX_BLOCK_AGE);
449}
450
451static bool __lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
452			struct extent_info *ei, enum extent_type type)
453{
454	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
455	struct extent_tree_info *eti = &sbi->extent_tree[type];
456	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
457	struct extent_node *en;
458	bool ret = false;
459
460	if (!et)
461		return false;
462
463	trace_f2fs_lookup_extent_tree_start(inode, pgofs, type);
464
465	read_lock(&et->lock);
466
467	if (type == EX_READ &&
468			et->largest.fofs <= pgofs &&
469			et->largest.fofs + et->largest.len > pgofs) {
470		*ei = et->largest;
471		ret = true;
472		stat_inc_largest_node_hit(sbi);
473		goto out;
474	}
475
476	en = __lookup_extent_node(&et->root, et->cached_en, pgofs);
477	if (!en)
478		goto out;
479
480	if (en == et->cached_en)
481		stat_inc_cached_node_hit(sbi, type);
482	else
483		stat_inc_rbtree_node_hit(sbi, type);
484
485	*ei = en->ei;
486	spin_lock(&eti->extent_lock);
487	if (!list_empty(&en->list)) {
488		list_move_tail(&en->list, &eti->extent_list);
489		et->cached_en = en;
490	}
491	spin_unlock(&eti->extent_lock);
492	ret = true;
493out:
494	stat_inc_total_hit(sbi, type);
495	read_unlock(&et->lock);
496
497	if (type == EX_READ)
498		trace_f2fs_lookup_read_extent_tree_end(inode, pgofs, ei);
499	else if (type == EX_BLOCK_AGE)
500		trace_f2fs_lookup_age_extent_tree_end(inode, pgofs, ei);
501	return ret;
502}
503
504static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
505				struct extent_tree *et, struct extent_info *ei,
506				struct extent_node *prev_ex,
507				struct extent_node *next_ex)
508{
509	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
510	struct extent_node *en = NULL;
511
512	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei, et->type)) {
513		prev_ex->ei.len += ei->len;
514		ei = &prev_ex->ei;
515		en = prev_ex;
516	}
517
518	if (next_ex && __is_front_mergeable(ei, &next_ex->ei, et->type)) {
519		next_ex->ei.fofs = ei->fofs;
520		next_ex->ei.len += ei->len;
521		if (et->type == EX_READ)
522			next_ex->ei.blk = ei->blk;
523		if (en)
524			__release_extent_node(sbi, et, prev_ex);
525
526		en = next_ex;
527	}
528
529	if (!en)
530		return NULL;
531
532	__try_update_largest_extent(et, en);
533
534	spin_lock(&eti->extent_lock);
535	if (!list_empty(&en->list)) {
536		list_move_tail(&en->list, &eti->extent_list);
537		et->cached_en = en;
538	}
539	spin_unlock(&eti->extent_lock);
540	return en;
541}
542
543static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
544				struct extent_tree *et, struct extent_info *ei,
545				struct rb_node **insert_p,
546				struct rb_node *insert_parent,
547				bool leftmost)
548{
549	struct extent_tree_info *eti = &sbi->extent_tree[et->type];
550	struct rb_node **p = &et->root.rb_root.rb_node;
551	struct rb_node *parent = NULL;
552	struct extent_node *en = NULL;
553
554	if (insert_p && insert_parent) {
555		parent = insert_parent;
556		p = insert_p;
557		goto do_insert;
558	}
559
560	leftmost = true;
561
562	/* look up extent_node in the rb tree */
563	while (*p) {
564		parent = *p;
565		en = rb_entry(parent, struct extent_node, rb_node);
566
567		if (ei->fofs < en->ei.fofs) {
568			p = &(*p)->rb_left;
569		} else if (ei->fofs >= en->ei.fofs + en->ei.len) {
570			p = &(*p)->rb_right;
571			leftmost = false;
572		} else {
573			f2fs_bug_on(sbi, 1);
574		}
575	}
576
577do_insert:
578	en = __attach_extent_node(sbi, et, ei, parent, p, leftmost);
579	if (!en)
580		return NULL;
581
582	__try_update_largest_extent(et, en);
583
584	/* update in global extent list */
585	spin_lock(&eti->extent_lock);
586	list_add_tail(&en->list, &eti->extent_list);
587	et->cached_en = en;
588	spin_unlock(&eti->extent_lock);
589	return en;
590}
591
592static void __update_extent_tree_range(struct inode *inode,
593			struct extent_info *tei, enum extent_type type)
594{
595	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
596	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
597	struct extent_node *en = NULL, *en1 = NULL;
598	struct extent_node *prev_en = NULL, *next_en = NULL;
599	struct extent_info ei, dei, prev;
600	struct rb_node **insert_p = NULL, *insert_parent = NULL;
601	unsigned int fofs = tei->fofs, len = tei->len;
602	unsigned int end = fofs + len;
603	bool updated = false;
604	bool leftmost = false;
605
606	if (!et)
607		return;
608
609	if (type == EX_READ)
610		trace_f2fs_update_read_extent_tree_range(inode, fofs, len,
611						tei->blk, 0);
612	else if (type == EX_BLOCK_AGE)
613		trace_f2fs_update_age_extent_tree_range(inode, fofs, len,
614						tei->age, tei->last_blocks);
615
616	write_lock(&et->lock);
617
618	if (type == EX_READ) {
619		if (is_inode_flag_set(inode, FI_NO_EXTENT)) {
620			write_unlock(&et->lock);
621			return;
622		}
623
624		prev = et->largest;
625		dei.len = 0;
626
627		/*
628		 * drop largest extent before lookup, in case it's already
629		 * been shrunk from extent tree
630		 */
631		__drop_largest_extent(et, fofs, len);
632	}
633
634	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
635	en = __lookup_extent_node_ret(&et->root,
636					et->cached_en, fofs,
637					&prev_en, &next_en,
638					&insert_p, &insert_parent,
639					&leftmost);
640	if (!en)
641		en = next_en;
642
643	/* 2. invalidate all extent nodes in range [fofs, fofs + len - 1] */
644	while (en && en->ei.fofs < end) {
645		unsigned int org_end;
646		int parts = 0;	/* # of parts current extent split into */
647
648		next_en = en1 = NULL;
649
650		dei = en->ei;
651		org_end = dei.fofs + dei.len;
652		f2fs_bug_on(sbi, fofs >= org_end);
653
654		if (fofs > dei.fofs && (type != EX_READ ||
655				fofs - dei.fofs >= F2FS_MIN_EXTENT_LEN)) {
656			en->ei.len = fofs - en->ei.fofs;
657			prev_en = en;
658			parts = 1;
659		}
660
661		if (end < org_end && (type != EX_READ ||
662				org_end - end >= F2FS_MIN_EXTENT_LEN)) {
663			if (parts) {
664				__set_extent_info(&ei,
665					end, org_end - end,
666					end - dei.fofs + dei.blk, false,
667					dei.age, dei.last_blocks,
668					type);
669				en1 = __insert_extent_tree(sbi, et, &ei,
670							NULL, NULL, true);
671				next_en = en1;
672			} else {
673				__set_extent_info(&en->ei,
674					end, en->ei.len - (end - dei.fofs),
675					en->ei.blk + (end - dei.fofs), true,
676					dei.age, dei.last_blocks,
677					type);
678				next_en = en;
679			}
680			parts++;
681		}
682
683		if (!next_en) {
684			struct rb_node *node = rb_next(&en->rb_node);
685
686			next_en = rb_entry_safe(node, struct extent_node,
687						rb_node);
688		}
689
690		if (parts)
691			__try_update_largest_extent(et, en);
692		else
693			__release_extent_node(sbi, et, en);
694
695		/*
696		 * if original extent is split into zero or two parts, extent
697		 * tree has been altered by deletion or insertion, therefore
698		 * invalidate pointers regard to tree.
699		 */
700		if (parts != 1) {
701			insert_p = NULL;
702			insert_parent = NULL;
703		}
704		en = next_en;
705	}
706
707	if (type == EX_BLOCK_AGE)
708		goto update_age_extent_cache;
709
710	/* 3. update extent in read extent cache */
711	BUG_ON(type != EX_READ);
712
713	if (tei->blk) {
714		__set_extent_info(&ei, fofs, len, tei->blk, false,
715				  0, 0, EX_READ);
716		if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
717			__insert_extent_tree(sbi, et, &ei,
718					insert_p, insert_parent, leftmost);
719
720		/* give up extent_cache, if split and small updates happen */
721		if (dei.len >= 1 &&
722				prev.len < F2FS_MIN_EXTENT_LEN &&
723				et->largest.len < F2FS_MIN_EXTENT_LEN) {
724			et->largest.len = 0;
725			et->largest_updated = true;
726			set_inode_flag(inode, FI_NO_EXTENT);
727		}
728	}
729
730	if (is_inode_flag_set(inode, FI_NO_EXTENT))
731		__free_extent_tree(sbi, et);
732
733	if (et->largest_updated) {
734		et->largest_updated = false;
735		updated = true;
736	}
737	goto out_read_extent_cache;
738update_age_extent_cache:
739	if (!tei->last_blocks)
740		goto out_read_extent_cache;
741
742	__set_extent_info(&ei, fofs, len, 0, false,
743			tei->age, tei->last_blocks, EX_BLOCK_AGE);
744	if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
745		__insert_extent_tree(sbi, et, &ei,
746					insert_p, insert_parent, leftmost);
747out_read_extent_cache:
748	write_unlock(&et->lock);
749
750	if (updated)
751		f2fs_mark_inode_dirty_sync(inode, true);
752}
753
754#ifdef CONFIG_F2FS_FS_COMPRESSION
755void f2fs_update_read_extent_tree_range_compressed(struct inode *inode,
756				pgoff_t fofs, block_t blkaddr, unsigned int llen,
757				unsigned int c_len)
758{
759	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
760	struct extent_tree *et = F2FS_I(inode)->extent_tree[EX_READ];
761	struct extent_node *en = NULL;
762	struct extent_node *prev_en = NULL, *next_en = NULL;
763	struct extent_info ei;
764	struct rb_node **insert_p = NULL, *insert_parent = NULL;
765	bool leftmost = false;
766
767	trace_f2fs_update_read_extent_tree_range(inode, fofs, llen,
768						blkaddr, c_len);
769
770	/* it is safe here to check FI_NO_EXTENT w/o et->lock in ro image */
771	if (is_inode_flag_set(inode, FI_NO_EXTENT))
772		return;
773
774	write_lock(&et->lock);
775
776	en = __lookup_extent_node_ret(&et->root,
777					et->cached_en, fofs,
778					&prev_en, &next_en,
779					&insert_p, &insert_parent,
780					&leftmost);
781	if (en)
782		goto unlock_out;
783
784	__set_extent_info(&ei, fofs, llen, blkaddr, true, 0, 0, EX_READ);
785	ei.c_len = c_len;
786
787	if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
788		__insert_extent_tree(sbi, et, &ei,
789				insert_p, insert_parent, leftmost);
790unlock_out:
791	write_unlock(&et->lock);
792}
793#endif
794
795static unsigned long long __calculate_block_age(struct f2fs_sb_info *sbi,
796						unsigned long long new,
797						unsigned long long old)
798{
799	unsigned int rem_old, rem_new;
800	unsigned long long res;
801	unsigned int weight = sbi->last_age_weight;
802
803	res = div_u64_rem(new, 100, &rem_new) * (100 - weight)
804		+ div_u64_rem(old, 100, &rem_old) * weight;
805
806	if (rem_new)
807		res += rem_new * (100 - weight) / 100;
808	if (rem_old)
809		res += rem_old * weight / 100;
810
811	return res;
812}
813
814/* This returns a new age and allocated blocks in ei */
815static int __get_new_block_age(struct inode *inode, struct extent_info *ei,
816						block_t blkaddr)
817{
818	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
819	loff_t f_size = i_size_read(inode);
820	unsigned long long cur_blocks =
821				atomic64_read(&sbi->allocated_data_blocks);
822	struct extent_info tei = *ei;	/* only fofs and len are valid */
823
824	/*
825	 * When I/O is not aligned to a PAGE_SIZE, update will happen to the last
826	 * file block even in seq write. So don't record age for newly last file
827	 * block here.
828	 */
829	if ((f_size >> PAGE_SHIFT) == ei->fofs && f_size & (PAGE_SIZE - 1) &&
830			blkaddr == NEW_ADDR)
831		return -EINVAL;
832
833	if (__lookup_extent_tree(inode, ei->fofs, &tei, EX_BLOCK_AGE)) {
834		unsigned long long cur_age;
835
836		if (cur_blocks >= tei.last_blocks)
837			cur_age = cur_blocks - tei.last_blocks;
838		else
839			/* allocated_data_blocks overflow */
840			cur_age = ULLONG_MAX - tei.last_blocks + cur_blocks;
841
842		if (tei.age)
843			ei->age = __calculate_block_age(sbi, cur_age, tei.age);
844		else
845			ei->age = cur_age;
846		ei->last_blocks = cur_blocks;
847		WARN_ON(ei->age > cur_blocks);
848		return 0;
849	}
850
851	f2fs_bug_on(sbi, blkaddr == NULL_ADDR);
852
853	/* the data block was allocated for the first time */
854	if (blkaddr == NEW_ADDR)
855		goto out;
856
857	if (__is_valid_data_blkaddr(blkaddr) &&
858	    !f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE))
859		return -EINVAL;
860out:
861	/*
862	 * init block age with zero, this can happen when the block age extent
863	 * was reclaimed due to memory constraint or system reboot
864	 */
865	ei->age = 0;
866	ei->last_blocks = cur_blocks;
867	return 0;
868}
869
870static void __update_extent_cache(struct dnode_of_data *dn, enum extent_type type)
871{
872	struct extent_info ei = {};
873
874	if (!__may_extent_tree(dn->inode, type))
875		return;
876
877	ei.fofs = f2fs_start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
878								dn->ofs_in_node;
879	ei.len = 1;
880
881	if (type == EX_READ) {
882		if (dn->data_blkaddr == NEW_ADDR)
883			ei.blk = NULL_ADDR;
884		else
885			ei.blk = dn->data_blkaddr;
886	} else if (type == EX_BLOCK_AGE) {
887		if (__get_new_block_age(dn->inode, &ei, dn->data_blkaddr))
888			return;
889	}
890	__update_extent_tree_range(dn->inode, &ei, type);
891}
892
893static unsigned int __shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink,
894					enum extent_type type)
895{
896	struct extent_tree_info *eti = &sbi->extent_tree[type];
897	struct extent_tree *et, *next;
898	struct extent_node *en;
899	unsigned int node_cnt = 0, tree_cnt = 0;
900	int remained;
901
902	if (!atomic_read(&eti->total_zombie_tree))
903		goto free_node;
904
905	if (!mutex_trylock(&eti->extent_tree_lock))
906		goto out;
907
908	/* 1. remove unreferenced extent tree */
909	list_for_each_entry_safe(et, next, &eti->zombie_list, list) {
910		if (atomic_read(&et->node_cnt)) {
911			write_lock(&et->lock);
912			node_cnt += __free_extent_tree(sbi, et);
913			write_unlock(&et->lock);
914		}
915		f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
916		list_del_init(&et->list);
917		radix_tree_delete(&eti->extent_tree_root, et->ino);
918		kmem_cache_free(extent_tree_slab, et);
919		atomic_dec(&eti->total_ext_tree);
920		atomic_dec(&eti->total_zombie_tree);
921		tree_cnt++;
922
923		if (node_cnt + tree_cnt >= nr_shrink)
924			goto unlock_out;
925		cond_resched();
926	}
927	mutex_unlock(&eti->extent_tree_lock);
928
929free_node:
930	/* 2. remove LRU extent entries */
931	if (!mutex_trylock(&eti->extent_tree_lock))
932		goto out;
933
934	remained = nr_shrink - (node_cnt + tree_cnt);
935
936	spin_lock(&eti->extent_lock);
937	for (; remained > 0; remained--) {
938		if (list_empty(&eti->extent_list))
939			break;
940		en = list_first_entry(&eti->extent_list,
941					struct extent_node, list);
942		et = en->et;
943		if (!write_trylock(&et->lock)) {
944			/* refresh this extent node's position in extent list */
945			list_move_tail(&en->list, &eti->extent_list);
946			continue;
947		}
948
949		list_del_init(&en->list);
950		spin_unlock(&eti->extent_lock);
951
952		__detach_extent_node(sbi, et, en);
953
954		write_unlock(&et->lock);
955		node_cnt++;
956		spin_lock(&eti->extent_lock);
957	}
958	spin_unlock(&eti->extent_lock);
959
960unlock_out:
961	mutex_unlock(&eti->extent_tree_lock);
962out:
963	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt, type);
964
965	return node_cnt + tree_cnt;
966}
967
968/* read extent cache operations */
969bool f2fs_lookup_read_extent_cache(struct inode *inode, pgoff_t pgofs,
970				struct extent_info *ei)
971{
972	if (!__may_extent_tree(inode, EX_READ))
973		return false;
974
975	return __lookup_extent_tree(inode, pgofs, ei, EX_READ);
976}
977
978bool f2fs_lookup_read_extent_cache_block(struct inode *inode, pgoff_t index,
979				block_t *blkaddr)
980{
981	struct extent_info ei = {};
982
983	if (!f2fs_lookup_read_extent_cache(inode, index, &ei))
984		return false;
985	*blkaddr = ei.blk + index - ei.fofs;
986	return true;
987}
988
989void f2fs_update_read_extent_cache(struct dnode_of_data *dn)
990{
991	return __update_extent_cache(dn, EX_READ);
992}
993
994void f2fs_update_read_extent_cache_range(struct dnode_of_data *dn,
995				pgoff_t fofs, block_t blkaddr, unsigned int len)
996{
997	struct extent_info ei = {
998		.fofs = fofs,
999		.len = len,
1000		.blk = blkaddr,
1001	};
1002
1003	if (!__may_extent_tree(dn->inode, EX_READ))
1004		return;
1005
1006	__update_extent_tree_range(dn->inode, &ei, EX_READ);
1007}
1008
1009unsigned int f2fs_shrink_read_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
1010{
1011	if (!test_opt(sbi, READ_EXTENT_CACHE))
1012		return 0;
1013
1014	return __shrink_extent_tree(sbi, nr_shrink, EX_READ);
1015}
1016
1017/* block age extent cache operations */
1018bool f2fs_lookup_age_extent_cache(struct inode *inode, pgoff_t pgofs,
1019				struct extent_info *ei)
1020{
1021	if (!__may_extent_tree(inode, EX_BLOCK_AGE))
1022		return false;
1023
1024	return __lookup_extent_tree(inode, pgofs, ei, EX_BLOCK_AGE);
1025}
1026
1027void f2fs_update_age_extent_cache(struct dnode_of_data *dn)
1028{
1029	return __update_extent_cache(dn, EX_BLOCK_AGE);
1030}
1031
1032void f2fs_update_age_extent_cache_range(struct dnode_of_data *dn,
1033				pgoff_t fofs, unsigned int len)
1034{
1035	struct extent_info ei = {
1036		.fofs = fofs,
1037		.len = len,
1038	};
1039
1040	if (!__may_extent_tree(dn->inode, EX_BLOCK_AGE))
1041		return;
1042
1043	__update_extent_tree_range(dn->inode, &ei, EX_BLOCK_AGE);
1044}
1045
1046unsigned int f2fs_shrink_age_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
1047{
1048	if (!test_opt(sbi, AGE_EXTENT_CACHE))
1049		return 0;
1050
1051	return __shrink_extent_tree(sbi, nr_shrink, EX_BLOCK_AGE);
1052}
1053
1054static unsigned int __destroy_extent_node(struct inode *inode,
1055					enum extent_type type)
1056{
1057	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1058	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
1059	unsigned int node_cnt = 0;
1060
1061	if (!et || !atomic_read(&et->node_cnt))
1062		return 0;
1063
1064	write_lock(&et->lock);
1065	node_cnt = __free_extent_tree(sbi, et);
1066	write_unlock(&et->lock);
1067
1068	return node_cnt;
1069}
1070
1071void f2fs_destroy_extent_node(struct inode *inode)
1072{
1073	__destroy_extent_node(inode, EX_READ);
1074	__destroy_extent_node(inode, EX_BLOCK_AGE);
1075}
1076
1077static void __drop_extent_tree(struct inode *inode, enum extent_type type)
1078{
1079	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1080	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
1081	bool updated = false;
1082
1083	if (!__may_extent_tree(inode, type))
1084		return;
1085
1086	write_lock(&et->lock);
1087	__free_extent_tree(sbi, et);
1088	if (type == EX_READ) {
1089		set_inode_flag(inode, FI_NO_EXTENT);
1090		if (et->largest.len) {
1091			et->largest.len = 0;
1092			updated = true;
1093		}
1094	}
1095	write_unlock(&et->lock);
1096	if (updated)
1097		f2fs_mark_inode_dirty_sync(inode, true);
1098}
1099
1100void f2fs_drop_extent_tree(struct inode *inode)
1101{
1102	__drop_extent_tree(inode, EX_READ);
1103	__drop_extent_tree(inode, EX_BLOCK_AGE);
1104}
1105
1106static void __destroy_extent_tree(struct inode *inode, enum extent_type type)
1107{
1108	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1109	struct extent_tree_info *eti = &sbi->extent_tree[type];
1110	struct extent_tree *et = F2FS_I(inode)->extent_tree[type];
1111	unsigned int node_cnt = 0;
1112
1113	if (!et)
1114		return;
1115
1116	if (inode->i_nlink && !is_bad_inode(inode) &&
1117					atomic_read(&et->node_cnt)) {
1118		mutex_lock(&eti->extent_tree_lock);
1119		list_add_tail(&et->list, &eti->zombie_list);
1120		atomic_inc(&eti->total_zombie_tree);
1121		mutex_unlock(&eti->extent_tree_lock);
1122		return;
1123	}
1124
1125	/* free all extent info belong to this extent tree */
1126	node_cnt = __destroy_extent_node(inode, type);
1127
1128	/* delete extent tree entry in radix tree */
1129	mutex_lock(&eti->extent_tree_lock);
1130	f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
1131	radix_tree_delete(&eti->extent_tree_root, inode->i_ino);
1132	kmem_cache_free(extent_tree_slab, et);
1133	atomic_dec(&eti->total_ext_tree);
1134	mutex_unlock(&eti->extent_tree_lock);
1135
1136	F2FS_I(inode)->extent_tree[type] = NULL;
1137
1138	trace_f2fs_destroy_extent_tree(inode, node_cnt, type);
1139}
1140
1141void f2fs_destroy_extent_tree(struct inode *inode)
1142{
1143	__destroy_extent_tree(inode, EX_READ);
1144	__destroy_extent_tree(inode, EX_BLOCK_AGE);
1145}
1146
1147static void __init_extent_tree_info(struct extent_tree_info *eti)
1148{
1149	INIT_RADIX_TREE(&eti->extent_tree_root, GFP_NOIO);
1150	mutex_init(&eti->extent_tree_lock);
1151	INIT_LIST_HEAD(&eti->extent_list);
1152	spin_lock_init(&eti->extent_lock);
1153	atomic_set(&eti->total_ext_tree, 0);
1154	INIT_LIST_HEAD(&eti->zombie_list);
1155	atomic_set(&eti->total_zombie_tree, 0);
1156	atomic_set(&eti->total_ext_node, 0);
1157}
1158
1159void f2fs_init_extent_cache_info(struct f2fs_sb_info *sbi)
1160{
1161	__init_extent_tree_info(&sbi->extent_tree[EX_READ]);
1162	__init_extent_tree_info(&sbi->extent_tree[EX_BLOCK_AGE]);
1163
1164	/* initialize for block age extents */
1165	atomic64_set(&sbi->allocated_data_blocks, 0);
1166	sbi->hot_data_age_threshold = DEF_HOT_DATA_AGE_THRESHOLD;
1167	sbi->warm_data_age_threshold = DEF_WARM_DATA_AGE_THRESHOLD;
1168	sbi->last_age_weight = LAST_AGE_WEIGHT;
1169}
1170
1171int __init f2fs_create_extent_cache(void)
1172{
1173	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
1174			sizeof(struct extent_tree));
1175	if (!extent_tree_slab)
1176		return -ENOMEM;
1177	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
1178			sizeof(struct extent_node));
1179	if (!extent_node_slab) {
1180		kmem_cache_destroy(extent_tree_slab);
1181		return -ENOMEM;
1182	}
1183	return 0;
1184}
1185
1186void f2fs_destroy_extent_cache(void)
1187{
1188	kmem_cache_destroy(extent_node_slab);
1189	kmem_cache_destroy(extent_tree_slab);
1190}
1191