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
 11#include <linux/fs.h>
 12#include <linux/f2fs_fs.h>
 13
 14#include "f2fs.h"
 15#include "node.h"
 16#include <trace/events/f2fs.h>
 17
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 18static struct rb_entry *__lookup_rb_tree_fast(struct rb_entry *cached_re,
 19							unsigned int ofs)
 20{
 21	if (cached_re) {
 22		if (cached_re->ofs <= ofs &&
 23				cached_re->ofs + cached_re->len > ofs) {
 24			return cached_re;
 25		}
 26	}
 27	return NULL;
 28}
 29
 30static struct rb_entry *__lookup_rb_tree_slow(struct rb_root_cached *root,
 31							unsigned int ofs)
 32{
 33	struct rb_node *node = root->rb_root.rb_node;
 34	struct rb_entry *re;
 35
 36	while (node) {
 37		re = rb_entry(node, struct rb_entry, rb_node);
 38
 39		if (ofs < re->ofs)
 40			node = node->rb_left;
 41		else if (ofs >= re->ofs + re->len)
 42			node = node->rb_right;
 43		else
 44			return re;
 45	}
 46	return NULL;
 47}
 48
 49struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
 50				struct rb_entry *cached_re, unsigned int ofs)
 51{
 52	struct rb_entry *re;
 53
 54	re = __lookup_rb_tree_fast(cached_re, ofs);
 55	if (!re)
 56		return __lookup_rb_tree_slow(root, ofs);
 57
 58	return re;
 59}
 60
 61struct rb_node **f2fs_lookup_rb_tree_ext(struct f2fs_sb_info *sbi,
 62					struct rb_root_cached *root,
 63					struct rb_node **parent,
 64					unsigned long long key, bool *leftmost)
 65{
 66	struct rb_node **p = &root->rb_root.rb_node;
 67	struct rb_entry *re;
 68
 69	while (*p) {
 70		*parent = *p;
 71		re = rb_entry(*parent, struct rb_entry, rb_node);
 72
 73		if (key < re->key) {
 74			p = &(*p)->rb_left;
 75		} else {
 76			p = &(*p)->rb_right;
 77			*leftmost = false;
 78		}
 79	}
 80
 81	return p;
 82}
 83
 84struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
 85				struct rb_root_cached *root,
 86				struct rb_node **parent,
 87				unsigned int ofs, bool *leftmost)
 88{
 89	struct rb_node **p = &root->rb_root.rb_node;
 90	struct rb_entry *re;
 91
 92	while (*p) {
 93		*parent = *p;
 94		re = rb_entry(*parent, struct rb_entry, rb_node);
 95
 96		if (ofs < re->ofs) {
 97			p = &(*p)->rb_left;
 98		} else if (ofs >= re->ofs + re->len) {
 99			p = &(*p)->rb_right;
100			*leftmost = false;
101		} else {
102			f2fs_bug_on(sbi, 1);
103		}
104	}
105
106	return p;
107}
108
109/*
110 * lookup rb entry in position of @ofs in rb-tree,
111 * if hit, return the entry, otherwise, return NULL
112 * @prev_ex: extent before ofs
113 * @next_ex: extent after ofs
114 * @insert_p: insert point for new extent at ofs
115 * in order to simpfy the insertion after.
116 * tree must stay unchanged between lookup and insertion.
117 */
118struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
119				struct rb_entry *cached_re,
120				unsigned int ofs,
121				struct rb_entry **prev_entry,
122				struct rb_entry **next_entry,
123				struct rb_node ***insert_p,
124				struct rb_node **insert_parent,
125				bool force, bool *leftmost)
126{
127	struct rb_node **pnode = &root->rb_root.rb_node;
128	struct rb_node *parent = NULL, *tmp_node;
129	struct rb_entry *re = cached_re;
130
131	*insert_p = NULL;
132	*insert_parent = NULL;
133	*prev_entry = NULL;
134	*next_entry = NULL;
135
136	if (RB_EMPTY_ROOT(&root->rb_root))
137		return NULL;
138
139	if (re) {
140		if (re->ofs <= ofs && re->ofs + re->len > ofs)
141			goto lookup_neighbors;
142	}
143
144	if (leftmost)
145		*leftmost = true;
146
147	while (*pnode) {
148		parent = *pnode;
149		re = rb_entry(*pnode, struct rb_entry, rb_node);
150
151		if (ofs < re->ofs) {
152			pnode = &(*pnode)->rb_left;
153		} else if (ofs >= re->ofs + re->len) {
154			pnode = &(*pnode)->rb_right;
155			if (leftmost)
156				*leftmost = false;
157		} else {
158			goto lookup_neighbors;
159		}
160	}
161
162	*insert_p = pnode;
163	*insert_parent = parent;
164
165	re = rb_entry(parent, struct rb_entry, rb_node);
166	tmp_node = parent;
167	if (parent && ofs > re->ofs)
168		tmp_node = rb_next(parent);
169	*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
170
171	tmp_node = parent;
172	if (parent && ofs < re->ofs)
173		tmp_node = rb_prev(parent);
174	*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
175	return NULL;
176
177lookup_neighbors:
178	if (ofs == re->ofs || force) {
179		/* lookup prev node for merging backward later */
180		tmp_node = rb_prev(&re->rb_node);
181		*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
182	}
183	if (ofs == re->ofs + re->len - 1 || force) {
184		/* lookup next node for merging frontward later */
185		tmp_node = rb_next(&re->rb_node);
186		*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
187	}
188	return re;
189}
190
191bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
192				struct rb_root_cached *root, bool check_key)
193{
194#ifdef CONFIG_F2FS_CHECK_FS
195	struct rb_node *cur = rb_first_cached(root), *next;
196	struct rb_entry *cur_re, *next_re;
197
198	if (!cur)
199		return true;
200
201	while (cur) {
202		next = rb_next(cur);
203		if (!next)
204			return true;
205
206		cur_re = rb_entry(cur, struct rb_entry, rb_node);
207		next_re = rb_entry(next, struct rb_entry, rb_node);
208
209		if (check_key) {
210			if (cur_re->key > next_re->key) {
211				f2fs_info(sbi, "inconsistent rbtree, "
212					"cur(%llu) next(%llu)",
213					cur_re->key, next_re->key);
214				return false;
215			}
216			goto next;
217		}
218
219		if (cur_re->ofs + cur_re->len > next_re->ofs) {
220			f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)",
221				  cur_re->ofs, cur_re->len,
222				  next_re->ofs, next_re->len);
223			return false;
224		}
225next:
226		cur = next;
227	}
228#endif
229	return true;
230}
231
232static struct kmem_cache *extent_tree_slab;
233static struct kmem_cache *extent_node_slab;
234
235static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
236				struct extent_tree *et, struct extent_info *ei,
237				struct rb_node *parent, struct rb_node **p,
238				bool leftmost)
239{
 
240	struct extent_node *en;
241
242	en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
243	if (!en)
244		return NULL;
245
246	en->ei = *ei;
247	INIT_LIST_HEAD(&en->list);
248	en->et = et;
249
250	rb_link_node(&en->rb_node, parent, p);
251	rb_insert_color_cached(&en->rb_node, &et->root, leftmost);
252	atomic_inc(&et->node_cnt);
253	atomic_inc(&sbi->total_ext_node);
254	return en;
255}
256
257static void __detach_extent_node(struct f2fs_sb_info *sbi,
258				struct extent_tree *et, struct extent_node *en)
259{
 
 
260	rb_erase_cached(&en->rb_node, &et->root);
261	atomic_dec(&et->node_cnt);
262	atomic_dec(&sbi->total_ext_node);
263
264	if (et->cached_en == en)
265		et->cached_en = NULL;
266	kmem_cache_free(extent_node_slab, en);
267}
268
269/*
270 * Flow to release an extent_node:
271 * 1. list_del_init
272 * 2. __detach_extent_node
273 * 3. kmem_cache_free.
274 */
275static void __release_extent_node(struct f2fs_sb_info *sbi,
276			struct extent_tree *et, struct extent_node *en)
277{
278	spin_lock(&sbi->extent_lock);
 
 
279	f2fs_bug_on(sbi, list_empty(&en->list));
280	list_del_init(&en->list);
281	spin_unlock(&sbi->extent_lock);
282
283	__detach_extent_node(sbi, et, en);
284}
285
286static struct extent_tree *__grab_extent_tree(struct inode *inode)
 
287{
288	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 
289	struct extent_tree *et;
290	nid_t ino = inode->i_ino;
291
292	mutex_lock(&sbi->extent_tree_lock);
293	et = radix_tree_lookup(&sbi->extent_tree_root, ino);
294	if (!et) {
295		et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
296		f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
 
297		memset(et, 0, sizeof(struct extent_tree));
298		et->ino = ino;
 
299		et->root = RB_ROOT_CACHED;
300		et->cached_en = NULL;
301		rwlock_init(&et->lock);
302		INIT_LIST_HEAD(&et->list);
303		atomic_set(&et->node_cnt, 0);
304		atomic_inc(&sbi->total_ext_tree);
305	} else {
306		atomic_dec(&sbi->total_zombie_tree);
307		list_del_init(&et->list);
308	}
309	mutex_unlock(&sbi->extent_tree_lock);
310
311	/* never died until evict_inode */
312	F2FS_I(inode)->extent_tree = et;
313
314	return et;
315}
316
317static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
318				struct extent_tree *et, struct extent_info *ei)
319{
320	struct rb_node **p = &et->root.rb_root.rb_node;
321	struct extent_node *en;
322
323	en = __attach_extent_node(sbi, et, ei, NULL, p, true);
324	if (!en)
325		return NULL;
326
327	et->largest = en->ei;
328	et->cached_en = en;
329	return en;
330}
331
332static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
333					struct extent_tree *et)
334{
335	struct rb_node *node, *next;
336	struct extent_node *en;
337	unsigned int count = atomic_read(&et->node_cnt);
338
339	node = rb_first_cached(&et->root);
340	while (node) {
341		next = rb_next(node);
342		en = rb_entry(node, struct extent_node, rb_node);
343		__release_extent_node(sbi, et, en);
344		node = next;
345	}
346
347	return count - atomic_read(&et->node_cnt);
348}
349
350static void __drop_largest_extent(struct extent_tree *et,
351					pgoff_t fofs, unsigned int len)
352{
353	if (fofs < et->largest.fofs + et->largest.len &&
354			fofs + len > et->largest.fofs) {
355		et->largest.len = 0;
356		et->largest_updated = true;
357	}
358}
359
360/* return true, if inode page is changed */
361static void __f2fs_init_extent_tree(struct inode *inode, struct page *ipage)
362{
363	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
364	struct f2fs_extent *i_ext = ipage ? &F2FS_INODE(ipage)->i_ext : NULL;
 
365	struct extent_tree *et;
366	struct extent_node *en;
367	struct extent_info ei;
368
369	if (!f2fs_may_extent_tree(inode)) {
370		/* drop largest extent */
371		if (i_ext && i_ext->len) {
372			f2fs_wait_on_page_writeback(ipage, NODE, true, true);
373			i_ext->len = 0;
374			set_page_dirty(ipage);
375			return;
376		}
377		return;
378	}
379
380	et = __grab_extent_tree(inode);
381
382	if (!i_ext || !i_ext->len)
383		return;
384
385	get_extent_info(&ei, i_ext);
386
387	write_lock(&et->lock);
388	if (atomic_read(&et->node_cnt))
389		goto out;
390
391	en = __init_extent_tree(sbi, et, &ei);
 
392	if (en) {
393		spin_lock(&sbi->extent_lock);
394		list_add_tail(&en->list, &sbi->extent_list);
395		spin_unlock(&sbi->extent_lock);
 
 
 
396	}
397out:
398	write_unlock(&et->lock);
 
 
 
 
 
 
 
 
 
 
399}
400
401void f2fs_init_extent_tree(struct inode *inode, struct page *ipage)
402{
403	__f2fs_init_extent_tree(inode, ipage);
 
 
404
405	if (!F2FS_I(inode)->extent_tree)
406		set_inode_flag(inode, FI_NO_EXTENT);
 
407}
408
409static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
410							struct extent_info *ei)
411{
412	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
413	struct extent_tree *et = F2FS_I(inode)->extent_tree;
 
414	struct extent_node *en;
415	bool ret = false;
416
417	f2fs_bug_on(sbi, !et);
 
418
419	trace_f2fs_lookup_extent_tree_start(inode, pgofs);
420
421	read_lock(&et->lock);
422
423	if (et->largest.fofs <= pgofs &&
 
424			et->largest.fofs + et->largest.len > pgofs) {
425		*ei = et->largest;
426		ret = true;
427		stat_inc_largest_node_hit(sbi);
428		goto out;
429	}
430
431	en = (struct extent_node *)f2fs_lookup_rb_tree(&et->root,
432				(struct rb_entry *)et->cached_en, pgofs);
433	if (!en)
434		goto out;
435
436	if (en == et->cached_en)
437		stat_inc_cached_node_hit(sbi);
438	else
439		stat_inc_rbtree_node_hit(sbi);
440
441	*ei = en->ei;
442	spin_lock(&sbi->extent_lock);
443	if (!list_empty(&en->list)) {
444		list_move_tail(&en->list, &sbi->extent_list);
445		et->cached_en = en;
446	}
447	spin_unlock(&sbi->extent_lock);
448	ret = true;
449out:
450	stat_inc_total_hit(sbi);
451	read_unlock(&et->lock);
452
453	trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
 
 
 
454	return ret;
455}
456
457static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
458				struct extent_tree *et, struct extent_info *ei,
459				struct extent_node *prev_ex,
460				struct extent_node *next_ex)
461{
 
462	struct extent_node *en = NULL;
463
464	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
465		prev_ex->ei.len += ei->len;
466		ei = &prev_ex->ei;
467		en = prev_ex;
468	}
469
470	if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
471		next_ex->ei.fofs = ei->fofs;
472		next_ex->ei.blk = ei->blk;
473		next_ex->ei.len += ei->len;
 
 
474		if (en)
475			__release_extent_node(sbi, et, prev_ex);
476
477		en = next_ex;
478	}
479
480	if (!en)
481		return NULL;
482
483	__try_update_largest_extent(et, en);
484
485	spin_lock(&sbi->extent_lock);
486	if (!list_empty(&en->list)) {
487		list_move_tail(&en->list, &sbi->extent_list);
488		et->cached_en = en;
489	}
490	spin_unlock(&sbi->extent_lock);
491	return en;
492}
493
494static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
495				struct extent_tree *et, struct extent_info *ei,
496				struct rb_node **insert_p,
497				struct rb_node *insert_parent,
498				bool leftmost)
499{
 
500	struct rb_node **p;
501	struct rb_node *parent = NULL;
502	struct extent_node *en = NULL;
503
504	if (insert_p && insert_parent) {
505		parent = insert_parent;
506		p = insert_p;
507		goto do_insert;
508	}
509
510	leftmost = true;
511
512	p = f2fs_lookup_rb_tree_for_insert(sbi, &et->root, &parent,
513						ei->fofs, &leftmost);
514do_insert:
515	en = __attach_extent_node(sbi, et, ei, parent, p, leftmost);
516	if (!en)
517		return NULL;
518
519	__try_update_largest_extent(et, en);
520
521	/* update in global extent list */
522	spin_lock(&sbi->extent_lock);
523	list_add_tail(&en->list, &sbi->extent_list);
524	et->cached_en = en;
525	spin_unlock(&sbi->extent_lock);
526	return en;
527}
528
529static void f2fs_update_extent_tree_range(struct inode *inode,
530				pgoff_t fofs, block_t blkaddr, unsigned int len)
531{
532	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
533	struct extent_tree *et = F2FS_I(inode)->extent_tree;
534	struct extent_node *en = NULL, *en1 = NULL;
535	struct extent_node *prev_en = NULL, *next_en = NULL;
536	struct extent_info ei, dei, prev;
537	struct rb_node **insert_p = NULL, *insert_parent = NULL;
 
538	unsigned int end = fofs + len;
539	unsigned int pos = (unsigned int)fofs;
540	bool updated = false;
541	bool leftmost = false;
542
543	if (!et)
544		return;
545
546	trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
 
 
 
 
 
547
548	write_lock(&et->lock);
549
550	if (is_inode_flag_set(inode, FI_NO_EXTENT)) {
551		write_unlock(&et->lock);
552		return;
553	}
 
554
555	prev = et->largest;
556	dei.len = 0;
557
558	/*
559	 * drop largest extent before lookup, in case it's already
560	 * been shrunk from extent tree
561	 */
562	__drop_largest_extent(et, fofs, len);
 
563
564	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
565	en = (struct extent_node *)f2fs_lookup_rb_tree_ret(&et->root,
566					(struct rb_entry *)et->cached_en, fofs,
567					(struct rb_entry **)&prev_en,
568					(struct rb_entry **)&next_en,
569					&insert_p, &insert_parent, false,
570					&leftmost);
571	if (!en)
572		en = next_en;
573
574	/* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
575	while (en && en->ei.fofs < end) {
576		unsigned int org_end;
577		int parts = 0;	/* # of parts current extent split into */
578
579		next_en = en1 = NULL;
580
581		dei = en->ei;
582		org_end = dei.fofs + dei.len;
583		f2fs_bug_on(sbi, pos >= org_end);
584
585		if (pos > dei.fofs &&	pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
586			en->ei.len = pos - en->ei.fofs;
 
587			prev_en = en;
588			parts = 1;
589		}
590
591		if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
 
592			if (parts) {
593				set_extent_info(&ei, end,
594						end - dei.fofs + dei.blk,
595						org_end - end);
 
 
596				en1 = __insert_extent_tree(sbi, et, &ei,
597							NULL, NULL, true);
598				next_en = en1;
599			} else {
600				en->ei.fofs = end;
601				en->ei.blk += end - dei.fofs;
602				en->ei.len -= end - dei.fofs;
 
 
603				next_en = en;
604			}
605			parts++;
606		}
607
608		if (!next_en) {
609			struct rb_node *node = rb_next(&en->rb_node);
610
611			next_en = rb_entry_safe(node, struct extent_node,
612						rb_node);
613		}
614
615		if (parts)
616			__try_update_largest_extent(et, en);
617		else
618			__release_extent_node(sbi, et, en);
619
620		/*
621		 * if original extent is split into zero or two parts, extent
622		 * tree has been altered by deletion or insertion, therefore
623		 * invalidate pointers regard to tree.
624		 */
625		if (parts != 1) {
626			insert_p = NULL;
627			insert_parent = NULL;
628		}
629		en = next_en;
630	}
631
632	/* 3. update extent in extent cache */
633	if (blkaddr) {
634
635		set_extent_info(&ei, fofs, blkaddr, len);
 
 
 
 
 
636		if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
637			__insert_extent_tree(sbi, et, &ei,
638					insert_p, insert_parent, leftmost);
639
640		/* give up extent_cache, if split and small updates happen */
641		if (dei.len >= 1 &&
642				prev.len < F2FS_MIN_EXTENT_LEN &&
643				et->largest.len < F2FS_MIN_EXTENT_LEN) {
644			et->largest.len = 0;
645			et->largest_updated = true;
646			set_inode_flag(inode, FI_NO_EXTENT);
647		}
648	}
649
650	if (is_inode_flag_set(inode, FI_NO_EXTENT))
651		__free_extent_tree(sbi, et);
652
653	if (et->largest_updated) {
654		et->largest_updated = false;
655		updated = true;
656	}
657
 
 
 
 
 
 
 
 
 
 
658	write_unlock(&et->lock);
659
660	if (updated)
661		f2fs_mark_inode_dirty_sync(inode, true);
662}
663
664unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 
 
 
665{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
666	struct extent_tree *et, *next;
667	struct extent_node *en;
668	unsigned int node_cnt = 0, tree_cnt = 0;
669	int remained;
670
671	if (!test_opt(sbi, EXTENT_CACHE))
672		return 0;
673
674	if (!atomic_read(&sbi->total_zombie_tree))
675		goto free_node;
676
677	if (!mutex_trylock(&sbi->extent_tree_lock))
678		goto out;
679
680	/* 1. remove unreferenced extent tree */
681	list_for_each_entry_safe(et, next, &sbi->zombie_list, list) {
682		if (atomic_read(&et->node_cnt)) {
683			write_lock(&et->lock);
684			node_cnt += __free_extent_tree(sbi, et);
685			write_unlock(&et->lock);
686		}
687		f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
688		list_del_init(&et->list);
689		radix_tree_delete(&sbi->extent_tree_root, et->ino);
690		kmem_cache_free(extent_tree_slab, et);
691		atomic_dec(&sbi->total_ext_tree);
692		atomic_dec(&sbi->total_zombie_tree);
693		tree_cnt++;
694
695		if (node_cnt + tree_cnt >= nr_shrink)
696			goto unlock_out;
697		cond_resched();
698	}
699	mutex_unlock(&sbi->extent_tree_lock);
700
701free_node:
702	/* 2. remove LRU extent entries */
703	if (!mutex_trylock(&sbi->extent_tree_lock))
704		goto out;
705
706	remained = nr_shrink - (node_cnt + tree_cnt);
707
708	spin_lock(&sbi->extent_lock);
709	for (; remained > 0; remained--) {
710		if (list_empty(&sbi->extent_list))
711			break;
712		en = list_first_entry(&sbi->extent_list,
713					struct extent_node, list);
714		et = en->et;
715		if (!write_trylock(&et->lock)) {
716			/* refresh this extent node's position in extent list */
717			list_move_tail(&en->list, &sbi->extent_list);
718			continue;
719		}
720
721		list_del_init(&en->list);
722		spin_unlock(&sbi->extent_lock);
723
724		__detach_extent_node(sbi, et, en);
725
726		write_unlock(&et->lock);
727		node_cnt++;
728		spin_lock(&sbi->extent_lock);
729	}
730	spin_unlock(&sbi->extent_lock);
731
732unlock_out:
733	mutex_unlock(&sbi->extent_tree_lock);
734out:
735	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt);
736
737	return node_cnt + tree_cnt;
738}
739
740unsigned int f2fs_destroy_extent_node(struct inode *inode)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
741{
742	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
743	struct extent_tree *et = F2FS_I(inode)->extent_tree;
744	unsigned int node_cnt = 0;
745
746	if (!et || !atomic_read(&et->node_cnt))
747		return 0;
748
749	write_lock(&et->lock);
750	node_cnt = __free_extent_tree(sbi, et);
751	write_unlock(&et->lock);
752
753	return node_cnt;
754}
755
756void f2fs_drop_extent_tree(struct inode *inode)
 
 
 
 
 
 
757{
758	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
759	struct extent_tree *et = F2FS_I(inode)->extent_tree;
760	bool updated = false;
761
762	if (!f2fs_may_extent_tree(inode))
763		return;
764
765	set_inode_flag(inode, FI_NO_EXTENT);
766
767	write_lock(&et->lock);
768	__free_extent_tree(sbi, et);
769	if (et->largest.len) {
770		et->largest.len = 0;
771		updated = true;
 
 
 
772	}
773	write_unlock(&et->lock);
774	if (updated)
775		f2fs_mark_inode_dirty_sync(inode, true);
776}
777
778void f2fs_destroy_extent_tree(struct inode *inode)
 
 
 
 
 
 
779{
780	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
781	struct extent_tree *et = F2FS_I(inode)->extent_tree;
 
782	unsigned int node_cnt = 0;
783
784	if (!et)
785		return;
786
787	if (inode->i_nlink && !is_bad_inode(inode) &&
788					atomic_read(&et->node_cnt)) {
789		mutex_lock(&sbi->extent_tree_lock);
790		list_add_tail(&et->list, &sbi->zombie_list);
791		atomic_inc(&sbi->total_zombie_tree);
792		mutex_unlock(&sbi->extent_tree_lock);
793		return;
794	}
795
796	/* free all extent info belong to this extent tree */
797	node_cnt = f2fs_destroy_extent_node(inode);
798
799	/* delete extent tree entry in radix tree */
800	mutex_lock(&sbi->extent_tree_lock);
801	f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
802	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
803	kmem_cache_free(extent_tree_slab, et);
804	atomic_dec(&sbi->total_ext_tree);
805	mutex_unlock(&sbi->extent_tree_lock);
806
807	F2FS_I(inode)->extent_tree = NULL;
808
809	trace_f2fs_destroy_extent_tree(inode, node_cnt);
810}
811
812bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
813					struct extent_info *ei)
814{
815	if (!f2fs_may_extent_tree(inode))
816		return false;
817
818	return f2fs_lookup_extent_tree(inode, pgofs, ei);
819}
820
821void f2fs_update_extent_cache(struct dnode_of_data *dn)
822{
823	pgoff_t fofs;
824	block_t blkaddr;
825
826	if (!f2fs_may_extent_tree(dn->inode))
827		return;
828
829	if (dn->data_blkaddr == NEW_ADDR)
830		blkaddr = NULL_ADDR;
831	else
832		blkaddr = dn->data_blkaddr;
833
834	fofs = f2fs_start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
835								dn->ofs_in_node;
836	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, 1);
837}
838
839void f2fs_update_extent_cache_range(struct dnode_of_data *dn,
840				pgoff_t fofs, block_t blkaddr, unsigned int len)
841
842{
843	if (!f2fs_may_extent_tree(dn->inode))
844		return;
845
846	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len);
 
 
 
 
847}
848
849void f2fs_init_extent_cache_info(struct f2fs_sb_info *sbi)
850{
851	INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
852	mutex_init(&sbi->extent_tree_lock);
853	INIT_LIST_HEAD(&sbi->extent_list);
854	spin_lock_init(&sbi->extent_lock);
855	atomic_set(&sbi->total_ext_tree, 0);
856	INIT_LIST_HEAD(&sbi->zombie_list);
857	atomic_set(&sbi->total_zombie_tree, 0);
858	atomic_set(&sbi->total_ext_node, 0);
859}
860
861int __init f2fs_create_extent_cache(void)
862{
863	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
864			sizeof(struct extent_tree));
865	if (!extent_tree_slab)
866		return -ENOMEM;
867	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
868			sizeof(struct extent_node));
869	if (!extent_node_slab) {
870		kmem_cache_destroy(extent_tree_slab);
871		return -ENOMEM;
872	}
873	return 0;
874}
875
876void f2fs_destroy_extent_cache(void)
877{
878	kmem_cache_destroy(extent_node_slab);
879	kmem_cache_destroy(extent_tree_slab);
880}