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v5.14.15
  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}
v4.6
 
  1/*
  2 * f2fs extent cache support
  3 *
  4 * Copyright (c) 2015 Motorola Mobility
  5 * Copyright (c) 2015 Samsung Electronics
  6 * Authors: Jaegeuk Kim <jaegeuk@kernel.org>
  7 *          Chao Yu <chao2.yu@samsung.com>
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License version 2 as
 11 * published by the Free Software Foundation.
 12 */
 13
 14#include <linux/fs.h>
 15#include <linux/f2fs_fs.h>
 16
 17#include "f2fs.h"
 18#include "node.h"
 19#include <trace/events/f2fs.h>
 20
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 21static struct kmem_cache *extent_tree_slab;
 22static struct kmem_cache *extent_node_slab;
 23
 24static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
 25				struct extent_tree *et, struct extent_info *ei,
 26				struct rb_node *parent, struct rb_node **p)
 
 27{
 28	struct extent_node *en;
 29
 30	en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
 31	if (!en)
 32		return NULL;
 33
 34	en->ei = *ei;
 35	INIT_LIST_HEAD(&en->list);
 36	en->et = et;
 37
 38	rb_link_node(&en->rb_node, parent, p);
 39	rb_insert_color(&en->rb_node, &et->root);
 40	atomic_inc(&et->node_cnt);
 41	atomic_inc(&sbi->total_ext_node);
 42	return en;
 43}
 44
 45static void __detach_extent_node(struct f2fs_sb_info *sbi,
 46				struct extent_tree *et, struct extent_node *en)
 47{
 48	rb_erase(&en->rb_node, &et->root);
 49	atomic_dec(&et->node_cnt);
 50	atomic_dec(&sbi->total_ext_node);
 51
 52	if (et->cached_en == en)
 53		et->cached_en = NULL;
 54	kmem_cache_free(extent_node_slab, en);
 55}
 56
 57/*
 58 * Flow to release an extent_node:
 59 * 1. list_del_init
 60 * 2. __detach_extent_node
 61 * 3. kmem_cache_free.
 62 */
 63static void __release_extent_node(struct f2fs_sb_info *sbi,
 64			struct extent_tree *et, struct extent_node *en)
 65{
 66	spin_lock(&sbi->extent_lock);
 67	f2fs_bug_on(sbi, list_empty(&en->list));
 68	list_del_init(&en->list);
 69	spin_unlock(&sbi->extent_lock);
 70
 71	__detach_extent_node(sbi, et, en);
 72}
 73
 74static struct extent_tree *__grab_extent_tree(struct inode *inode)
 75{
 76	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 77	struct extent_tree *et;
 78	nid_t ino = inode->i_ino;
 79
 80	down_write(&sbi->extent_tree_lock);
 81	et = radix_tree_lookup(&sbi->extent_tree_root, ino);
 82	if (!et) {
 83		et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
 84		f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
 85		memset(et, 0, sizeof(struct extent_tree));
 86		et->ino = ino;
 87		et->root = RB_ROOT;
 88		et->cached_en = NULL;
 89		rwlock_init(&et->lock);
 90		INIT_LIST_HEAD(&et->list);
 91		atomic_set(&et->node_cnt, 0);
 92		atomic_inc(&sbi->total_ext_tree);
 93	} else {
 94		atomic_dec(&sbi->total_zombie_tree);
 95		list_del_init(&et->list);
 96	}
 97	up_write(&sbi->extent_tree_lock);
 98
 99	/* never died until evict_inode */
100	F2FS_I(inode)->extent_tree = et;
101
102	return et;
103}
104
105static struct extent_node *__lookup_extent_tree(struct f2fs_sb_info *sbi,
106				struct extent_tree *et, unsigned int fofs)
107{
108	struct rb_node *node = et->root.rb_node;
109	struct extent_node *en = et->cached_en;
110
111	if (en) {
112		struct extent_info *cei = &en->ei;
113
114		if (cei->fofs <= fofs && cei->fofs + cei->len > fofs) {
115			stat_inc_cached_node_hit(sbi);
116			return en;
117		}
118	}
119
120	while (node) {
121		en = rb_entry(node, struct extent_node, rb_node);
122
123		if (fofs < en->ei.fofs) {
124			node = node->rb_left;
125		} else if (fofs >= en->ei.fofs + en->ei.len) {
126			node = node->rb_right;
127		} else {
128			stat_inc_rbtree_node_hit(sbi);
129			return en;
130		}
131	}
132	return NULL;
133}
134
135static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
136				struct extent_tree *et, struct extent_info *ei)
137{
138	struct rb_node **p = &et->root.rb_node;
139	struct extent_node *en;
140
141	en = __attach_extent_node(sbi, et, ei, NULL, p);
142	if (!en)
143		return NULL;
144
145	et->largest = en->ei;
146	et->cached_en = en;
147	return en;
148}
149
150static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
151					struct extent_tree *et)
152{
153	struct rb_node *node, *next;
154	struct extent_node *en;
155	unsigned int count = atomic_read(&et->node_cnt);
156
157	node = rb_first(&et->root);
158	while (node) {
159		next = rb_next(node);
160		en = rb_entry(node, struct extent_node, rb_node);
161		__release_extent_node(sbi, et, en);
162		node = next;
163	}
164
165	return count - atomic_read(&et->node_cnt);
166}
167
168static void __drop_largest_extent(struct inode *inode,
169					pgoff_t fofs, unsigned int len)
170{
171	struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
172
173	if (fofs < largest->fofs + largest->len && fofs + len > largest->fofs)
174		largest->len = 0;
 
175}
176
177/* return true, if inode page is changed */
178bool f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
179{
180	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 
181	struct extent_tree *et;
182	struct extent_node *en;
183	struct extent_info ei;
184
185	if (!f2fs_may_extent_tree(inode)) {
186		/* drop largest extent */
187		if (i_ext && i_ext->len) {
 
188			i_ext->len = 0;
189			return true;
 
190		}
191		return false;
192	}
193
194	et = __grab_extent_tree(inode);
195
196	if (!i_ext || !i_ext->len)
197		return false;
198
199	set_extent_info(&ei, le32_to_cpu(i_ext->fofs),
200		le32_to_cpu(i_ext->blk), le32_to_cpu(i_ext->len));
201
202	write_lock(&et->lock);
203	if (atomic_read(&et->node_cnt))
204		goto out;
205
206	en = __init_extent_tree(sbi, et, &ei);
207	if (en) {
208		spin_lock(&sbi->extent_lock);
209		list_add_tail(&en->list, &sbi->extent_list);
210		spin_unlock(&sbi->extent_lock);
211	}
212out:
213	write_unlock(&et->lock);
214	return false;
 
 
 
 
 
 
 
215}
216
217static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
218							struct extent_info *ei)
219{
220	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
221	struct extent_tree *et = F2FS_I(inode)->extent_tree;
222	struct extent_node *en;
223	bool ret = false;
224
225	f2fs_bug_on(sbi, !et);
226
227	trace_f2fs_lookup_extent_tree_start(inode, pgofs);
228
229	read_lock(&et->lock);
230
231	if (et->largest.fofs <= pgofs &&
232			et->largest.fofs + et->largest.len > pgofs) {
233		*ei = et->largest;
234		ret = true;
235		stat_inc_largest_node_hit(sbi);
236		goto out;
237	}
238
239	en = __lookup_extent_tree(sbi, et, pgofs);
240	if (en) {
241		*ei = en->ei;
242		spin_lock(&sbi->extent_lock);
243		if (!list_empty(&en->list)) {
244			list_move_tail(&en->list, &sbi->extent_list);
245			et->cached_en = en;
246		}
247		spin_unlock(&sbi->extent_lock);
248		ret = true;
 
 
 
 
 
249	}
 
 
250out:
251	stat_inc_total_hit(sbi);
252	read_unlock(&et->lock);
253
254	trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
255	return ret;
256}
257
258
259/*
260 * lookup extent at @fofs, if hit, return the extent
261 * if not, return NULL and
262 * @prev_ex: extent before fofs
263 * @next_ex: extent after fofs
264 * @insert_p: insert point for new extent at fofs
265 * in order to simpfy the insertion after.
266 * tree must stay unchanged between lookup and insertion.
267 */
268static struct extent_node *__lookup_extent_tree_ret(struct extent_tree *et,
269				unsigned int fofs,
270				struct extent_node **prev_ex,
271				struct extent_node **next_ex,
272				struct rb_node ***insert_p,
273				struct rb_node **insert_parent)
274{
275	struct rb_node **pnode = &et->root.rb_node;
276	struct rb_node *parent = NULL, *tmp_node;
277	struct extent_node *en = et->cached_en;
278
279	*insert_p = NULL;
280	*insert_parent = NULL;
281	*prev_ex = NULL;
282	*next_ex = NULL;
283
284	if (RB_EMPTY_ROOT(&et->root))
285		return NULL;
286
287	if (en) {
288		struct extent_info *cei = &en->ei;
289
290		if (cei->fofs <= fofs && cei->fofs + cei->len > fofs)
291			goto lookup_neighbors;
292	}
293
294	while (*pnode) {
295		parent = *pnode;
296		en = rb_entry(*pnode, struct extent_node, rb_node);
297
298		if (fofs < en->ei.fofs)
299			pnode = &(*pnode)->rb_left;
300		else if (fofs >= en->ei.fofs + en->ei.len)
301			pnode = &(*pnode)->rb_right;
302		else
303			goto lookup_neighbors;
304	}
305
306	*insert_p = pnode;
307	*insert_parent = parent;
308
309	en = rb_entry(parent, struct extent_node, rb_node);
310	tmp_node = parent;
311	if (parent && fofs > en->ei.fofs)
312		tmp_node = rb_next(parent);
313	*next_ex = tmp_node ?
314		rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
315
316	tmp_node = parent;
317	if (parent && fofs < en->ei.fofs)
318		tmp_node = rb_prev(parent);
319	*prev_ex = tmp_node ?
320		rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
321	return NULL;
322
323lookup_neighbors:
324	if (fofs == en->ei.fofs) {
325		/* lookup prev node for merging backward later */
326		tmp_node = rb_prev(&en->rb_node);
327		*prev_ex = tmp_node ?
328			rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
329	}
330	if (fofs == en->ei.fofs + en->ei.len - 1) {
331		/* lookup next node for merging frontward later */
332		tmp_node = rb_next(&en->rb_node);
333		*next_ex = tmp_node ?
334			rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
335	}
336	return en;
337}
338
339static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
340				struct extent_tree *et, struct extent_info *ei,
341				struct extent_node *prev_ex,
342				struct extent_node *next_ex)
343{
344	struct extent_node *en = NULL;
345
346	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
347		prev_ex->ei.len += ei->len;
348		ei = &prev_ex->ei;
349		en = prev_ex;
350	}
351
352	if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
353		if (en)
354			__release_extent_node(sbi, et, prev_ex);
355		next_ex->ei.fofs = ei->fofs;
356		next_ex->ei.blk = ei->blk;
357		next_ex->ei.len += ei->len;
 
 
 
358		en = next_ex;
359	}
360
361	if (!en)
362		return NULL;
363
364	__try_update_largest_extent(et, en);
365
366	spin_lock(&sbi->extent_lock);
367	if (!list_empty(&en->list)) {
368		list_move_tail(&en->list, &sbi->extent_list);
369		et->cached_en = en;
370	}
371	spin_unlock(&sbi->extent_lock);
372	return en;
373}
374
375static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
376				struct extent_tree *et, struct extent_info *ei,
377				struct rb_node **insert_p,
378				struct rb_node *insert_parent)
 
379{
380	struct rb_node **p = &et->root.rb_node;
381	struct rb_node *parent = NULL;
382	struct extent_node *en = NULL;
383
384	if (insert_p && insert_parent) {
385		parent = insert_parent;
386		p = insert_p;
387		goto do_insert;
388	}
389
390	while (*p) {
391		parent = *p;
392		en = rb_entry(parent, struct extent_node, rb_node);
393
394		if (ei->fofs < en->ei.fofs)
395			p = &(*p)->rb_left;
396		else if (ei->fofs >= en->ei.fofs + en->ei.len)
397			p = &(*p)->rb_right;
398		else
399			f2fs_bug_on(sbi, 1);
400	}
401do_insert:
402	en = __attach_extent_node(sbi, et, ei, parent, p);
403	if (!en)
404		return NULL;
405
406	__try_update_largest_extent(et, en);
407
408	/* update in global extent list */
409	spin_lock(&sbi->extent_lock);
410	list_add_tail(&en->list, &sbi->extent_list);
411	et->cached_en = en;
412	spin_unlock(&sbi->extent_lock);
413	return en;
414}
415
416static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
417				pgoff_t fofs, block_t blkaddr, unsigned int len)
418{
419	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
420	struct extent_tree *et = F2FS_I(inode)->extent_tree;
421	struct extent_node *en = NULL, *en1 = NULL;
422	struct extent_node *prev_en = NULL, *next_en = NULL;
423	struct extent_info ei, dei, prev;
424	struct rb_node **insert_p = NULL, *insert_parent = NULL;
425	unsigned int end = fofs + len;
426	unsigned int pos = (unsigned int)fofs;
 
 
427
428	if (!et)
429		return false;
430
431	trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
432
433	write_lock(&et->lock);
434
435	if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT)) {
436		write_unlock(&et->lock);
437		return false;
438	}
439
440	prev = et->largest;
441	dei.len = 0;
442
443	/*
444	 * drop largest extent before lookup, in case it's already
445	 * been shrunk from extent tree
446	 */
447	__drop_largest_extent(inode, fofs, len);
448
449	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
450	en = __lookup_extent_tree_ret(et, fofs, &prev_en, &next_en,
451					&insert_p, &insert_parent);
 
 
 
 
452	if (!en)
453		en = next_en;
454
455	/* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
456	while (en && en->ei.fofs < end) {
457		unsigned int org_end;
458		int parts = 0;	/* # of parts current extent split into */
459
460		next_en = en1 = NULL;
461
462		dei = en->ei;
463		org_end = dei.fofs + dei.len;
464		f2fs_bug_on(sbi, pos >= org_end);
465
466		if (pos > dei.fofs &&	pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
467			en->ei.len = pos - en->ei.fofs;
468			prev_en = en;
469			parts = 1;
470		}
471
472		if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
473			if (parts) {
474				set_extent_info(&ei, end,
475						end - dei.fofs + dei.blk,
476						org_end - end);
477				en1 = __insert_extent_tree(sbi, et, &ei,
478							NULL, NULL);
479				next_en = en1;
480			} else {
481				en->ei.fofs = end;
482				en->ei.blk += end - dei.fofs;
483				en->ei.len -= end - dei.fofs;
484				next_en = en;
485			}
486			parts++;
487		}
488
489		if (!next_en) {
490			struct rb_node *node = rb_next(&en->rb_node);
491
492			next_en = node ?
493				rb_entry(node, struct extent_node, rb_node)
494				: NULL;
495		}
496
497		if (parts)
498			__try_update_largest_extent(et, en);
499		else
500			__release_extent_node(sbi, et, en);
501
502		/*
503		 * if original extent is split into zero or two parts, extent
504		 * tree has been altered by deletion or insertion, therefore
505		 * invalidate pointers regard to tree.
506		 */
507		if (parts != 1) {
508			insert_p = NULL;
509			insert_parent = NULL;
510		}
511		en = next_en;
512	}
513
514	/* 3. update extent in extent cache */
515	if (blkaddr) {
516
517		set_extent_info(&ei, fofs, blkaddr, len);
518		if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en))
519			__insert_extent_tree(sbi, et, &ei,
520						insert_p, insert_parent);
521
522		/* give up extent_cache, if split and small updates happen */
523		if (dei.len >= 1 &&
524				prev.len < F2FS_MIN_EXTENT_LEN &&
525				et->largest.len < F2FS_MIN_EXTENT_LEN) {
526			et->largest.len = 0;
527			set_inode_flag(F2FS_I(inode), FI_NO_EXTENT);
 
528		}
529	}
530
531	if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))
532		__free_extent_tree(sbi, et);
533
 
 
 
 
 
534	write_unlock(&et->lock);
535
536	return !__is_extent_same(&prev, &et->largest);
 
537}
538
539unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
540{
541	struct extent_tree *et, *next;
542	struct extent_node *en;
543	unsigned int node_cnt = 0, tree_cnt = 0;
544	int remained;
545
546	if (!test_opt(sbi, EXTENT_CACHE))
547		return 0;
548
549	if (!atomic_read(&sbi->total_zombie_tree))
550		goto free_node;
551
552	if (!down_write_trylock(&sbi->extent_tree_lock))
553		goto out;
554
555	/* 1. remove unreferenced extent tree */
556	list_for_each_entry_safe(et, next, &sbi->zombie_list, list) {
557		if (atomic_read(&et->node_cnt)) {
558			write_lock(&et->lock);
559			node_cnt += __free_extent_tree(sbi, et);
560			write_unlock(&et->lock);
561		}
562		f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
563		list_del_init(&et->list);
564		radix_tree_delete(&sbi->extent_tree_root, et->ino);
565		kmem_cache_free(extent_tree_slab, et);
566		atomic_dec(&sbi->total_ext_tree);
567		atomic_dec(&sbi->total_zombie_tree);
568		tree_cnt++;
569
570		if (node_cnt + tree_cnt >= nr_shrink)
571			goto unlock_out;
572		cond_resched();
573	}
574	up_write(&sbi->extent_tree_lock);
575
576free_node:
577	/* 2. remove LRU extent entries */
578	if (!down_write_trylock(&sbi->extent_tree_lock))
579		goto out;
580
581	remained = nr_shrink - (node_cnt + tree_cnt);
582
583	spin_lock(&sbi->extent_lock);
584	for (; remained > 0; remained--) {
585		if (list_empty(&sbi->extent_list))
586			break;
587		en = list_first_entry(&sbi->extent_list,
588					struct extent_node, list);
589		et = en->et;
590		if (!write_trylock(&et->lock)) {
591			/* refresh this extent node's position in extent list */
592			list_move_tail(&en->list, &sbi->extent_list);
593			continue;
594		}
595
596		list_del_init(&en->list);
597		spin_unlock(&sbi->extent_lock);
598
599		__detach_extent_node(sbi, et, en);
600
601		write_unlock(&et->lock);
602		node_cnt++;
603		spin_lock(&sbi->extent_lock);
604	}
605	spin_unlock(&sbi->extent_lock);
606
607unlock_out:
608	up_write(&sbi->extent_tree_lock);
609out:
610	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt);
611
612	return node_cnt + tree_cnt;
613}
614
615unsigned int f2fs_destroy_extent_node(struct inode *inode)
616{
617	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
618	struct extent_tree *et = F2FS_I(inode)->extent_tree;
619	unsigned int node_cnt = 0;
620
621	if (!et || !atomic_read(&et->node_cnt))
622		return 0;
623
624	write_lock(&et->lock);
625	node_cnt = __free_extent_tree(sbi, et);
626	write_unlock(&et->lock);
627
628	return node_cnt;
629}
630
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
631void f2fs_destroy_extent_tree(struct inode *inode)
632{
633	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
634	struct extent_tree *et = F2FS_I(inode)->extent_tree;
635	unsigned int node_cnt = 0;
636
637	if (!et)
638		return;
639
640	if (inode->i_nlink && !is_bad_inode(inode) &&
641					atomic_read(&et->node_cnt)) {
642		down_write(&sbi->extent_tree_lock);
643		list_add_tail(&et->list, &sbi->zombie_list);
644		atomic_inc(&sbi->total_zombie_tree);
645		up_write(&sbi->extent_tree_lock);
646		return;
647	}
648
649	/* free all extent info belong to this extent tree */
650	node_cnt = f2fs_destroy_extent_node(inode);
651
652	/* delete extent tree entry in radix tree */
653	down_write(&sbi->extent_tree_lock);
654	f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
655	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
656	kmem_cache_free(extent_tree_slab, et);
657	atomic_dec(&sbi->total_ext_tree);
658	up_write(&sbi->extent_tree_lock);
659
660	F2FS_I(inode)->extent_tree = NULL;
661
662	trace_f2fs_destroy_extent_tree(inode, node_cnt);
663}
664
665bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
666					struct extent_info *ei)
667{
668	if (!f2fs_may_extent_tree(inode))
669		return false;
670
671	return f2fs_lookup_extent_tree(inode, pgofs, ei);
672}
673
674void f2fs_update_extent_cache(struct dnode_of_data *dn)
675{
676	pgoff_t fofs;
677	block_t blkaddr;
678
679	if (!f2fs_may_extent_tree(dn->inode))
680		return;
681
682	if (dn->data_blkaddr == NEW_ADDR)
683		blkaddr = NULL_ADDR;
684	else
685		blkaddr = dn->data_blkaddr;
686
687	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
688								dn->ofs_in_node;
689
690	if (f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, 1))
691		sync_inode_page(dn);
692}
693
694void f2fs_update_extent_cache_range(struct dnode_of_data *dn,
695				pgoff_t fofs, block_t blkaddr, unsigned int len)
696
697{
698	if (!f2fs_may_extent_tree(dn->inode))
699		return;
700
701	if (f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len))
702		sync_inode_page(dn);
703}
704
705void init_extent_cache_info(struct f2fs_sb_info *sbi)
706{
707	INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
708	init_rwsem(&sbi->extent_tree_lock);
709	INIT_LIST_HEAD(&sbi->extent_list);
710	spin_lock_init(&sbi->extent_lock);
711	atomic_set(&sbi->total_ext_tree, 0);
712	INIT_LIST_HEAD(&sbi->zombie_list);
713	atomic_set(&sbi->total_zombie_tree, 0);
714	atomic_set(&sbi->total_ext_node, 0);
715}
716
717int __init create_extent_cache(void)
718{
719	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
720			sizeof(struct extent_tree));
721	if (!extent_tree_slab)
722		return -ENOMEM;
723	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
724			sizeof(struct extent_node));
725	if (!extent_node_slab) {
726		kmem_cache_destroy(extent_tree_slab);
727		return -ENOMEM;
728	}
729	return 0;
730}
731
732void destroy_extent_cache(void)
733{
734	kmem_cache_destroy(extent_node_slab);
735	kmem_cache_destroy(extent_tree_slab);
736}