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  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 rb_entry *__lookup_rb_tree_fast(struct rb_entry *cached_re,
 22							unsigned int ofs)
 23{
 24	if (cached_re) {
 25		if (cached_re->ofs <= ofs &&
 26				cached_re->ofs + cached_re->len > ofs) {
 27			return cached_re;
 28		}
 29	}
 30	return NULL;
 31}
 32
 33static struct rb_entry *__lookup_rb_tree_slow(struct rb_root *root,
 34							unsigned int ofs)
 35{
 36	struct rb_node *node = root->rb_node;
 37	struct rb_entry *re;
 38
 39	while (node) {
 40		re = rb_entry(node, struct rb_entry, rb_node);
 41
 42		if (ofs < re->ofs)
 43			node = node->rb_left;
 44		else if (ofs >= re->ofs + re->len)
 45			node = node->rb_right;
 46		else
 47			return re;
 48	}
 49	return NULL;
 50}
 51
 52struct rb_entry *__lookup_rb_tree(struct rb_root *root,
 53				struct rb_entry *cached_re, unsigned int ofs)
 54{
 55	struct rb_entry *re;
 56
 57	re = __lookup_rb_tree_fast(cached_re, ofs);
 58	if (!re)
 59		return __lookup_rb_tree_slow(root, ofs);
 60
 61	return re;
 62}
 63
 64struct rb_node **__lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
 65				struct rb_root *root, struct rb_node **parent,
 66				unsigned int ofs)
 67{
 68	struct rb_node **p = &root->rb_node;
 69	struct rb_entry *re;
 70
 71	while (*p) {
 72		*parent = *p;
 73		re = rb_entry(*parent, struct rb_entry, rb_node);
 74
 75		if (ofs < re->ofs)
 76			p = &(*p)->rb_left;
 77		else if (ofs >= re->ofs + re->len)
 78			p = &(*p)->rb_right;
 79		else
 80			f2fs_bug_on(sbi, 1);
 81	}
 82
 83	return p;
 84}
 85
 86/*
 87 * lookup rb entry in position of @ofs in rb-tree,
 88 * if hit, return the entry, otherwise, return NULL
 89 * @prev_ex: extent before ofs
 90 * @next_ex: extent after ofs
 91 * @insert_p: insert point for new extent at ofs
 92 * in order to simpfy the insertion after.
 93 * tree must stay unchanged between lookup and insertion.
 94 */
 95struct rb_entry *__lookup_rb_tree_ret(struct rb_root *root,
 96				struct rb_entry *cached_re,
 97				unsigned int ofs,
 98				struct rb_entry **prev_entry,
 99				struct rb_entry **next_entry,
100				struct rb_node ***insert_p,
101				struct rb_node **insert_parent,
102				bool force)
103{
104	struct rb_node **pnode = &root->rb_node;
105	struct rb_node *parent = NULL, *tmp_node;
106	struct rb_entry *re = cached_re;
107
108	*insert_p = NULL;
109	*insert_parent = NULL;
110	*prev_entry = NULL;
111	*next_entry = NULL;
112
113	if (RB_EMPTY_ROOT(root))
114		return NULL;
115
116	if (re) {
117		if (re->ofs <= ofs && re->ofs + re->len > ofs)
118			goto lookup_neighbors;
119	}
120
121	while (*pnode) {
122		parent = *pnode;
123		re = rb_entry(*pnode, struct rb_entry, rb_node);
124
125		if (ofs < re->ofs)
126			pnode = &(*pnode)->rb_left;
127		else if (ofs >= re->ofs + re->len)
128			pnode = &(*pnode)->rb_right;
129		else
130			goto lookup_neighbors;
131	}
132
133	*insert_p = pnode;
134	*insert_parent = parent;
135
136	re = rb_entry(parent, struct rb_entry, rb_node);
137	tmp_node = parent;
138	if (parent && ofs > re->ofs)
139		tmp_node = rb_next(parent);
140	*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
141
142	tmp_node = parent;
143	if (parent && ofs < re->ofs)
144		tmp_node = rb_prev(parent);
145	*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
146	return NULL;
147
148lookup_neighbors:
149	if (ofs == re->ofs || force) {
150		/* lookup prev node for merging backward later */
151		tmp_node = rb_prev(&re->rb_node);
152		*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
153	}
154	if (ofs == re->ofs + re->len - 1 || force) {
155		/* lookup next node for merging frontward later */
156		tmp_node = rb_next(&re->rb_node);
157		*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
158	}
159	return re;
160}
161
162bool __check_rb_tree_consistence(struct f2fs_sb_info *sbi,
163						struct rb_root *root)
164{
165#ifdef CONFIG_F2FS_CHECK_FS
166	struct rb_node *cur = rb_first(root), *next;
167	struct rb_entry *cur_re, *next_re;
168
169	if (!cur)
170		return true;
171
172	while (cur) {
173		next = rb_next(cur);
174		if (!next)
175			return true;
176
177		cur_re = rb_entry(cur, struct rb_entry, rb_node);
178		next_re = rb_entry(next, struct rb_entry, rb_node);
179
180		if (cur_re->ofs + cur_re->len > next_re->ofs) {
181			f2fs_msg(sbi->sb, KERN_INFO, "inconsistent rbtree, "
182				"cur(%u, %u) next(%u, %u)",
183				cur_re->ofs, cur_re->len,
184				next_re->ofs, next_re->len);
185			return false;
186		}
187
188		cur = next;
189	}
190#endif
191	return true;
192}
193
194static struct kmem_cache *extent_tree_slab;
195static struct kmem_cache *extent_node_slab;
196
197static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
198				struct extent_tree *et, struct extent_info *ei,
199				struct rb_node *parent, struct rb_node **p)
200{
201	struct extent_node *en;
202
203	en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
204	if (!en)
205		return NULL;
206
207	en->ei = *ei;
208	INIT_LIST_HEAD(&en->list);
209	en->et = et;
210
211	rb_link_node(&en->rb_node, parent, p);
212	rb_insert_color(&en->rb_node, &et->root);
213	atomic_inc(&et->node_cnt);
214	atomic_inc(&sbi->total_ext_node);
215	return en;
216}
217
218static void __detach_extent_node(struct f2fs_sb_info *sbi,
219				struct extent_tree *et, struct extent_node *en)
220{
221	rb_erase(&en->rb_node, &et->root);
222	atomic_dec(&et->node_cnt);
223	atomic_dec(&sbi->total_ext_node);
224
225	if (et->cached_en == en)
226		et->cached_en = NULL;
227	kmem_cache_free(extent_node_slab, en);
228}
229
230/*
231 * Flow to release an extent_node:
232 * 1. list_del_init
233 * 2. __detach_extent_node
234 * 3. kmem_cache_free.
235 */
236static void __release_extent_node(struct f2fs_sb_info *sbi,
237			struct extent_tree *et, struct extent_node *en)
238{
239	spin_lock(&sbi->extent_lock);
240	f2fs_bug_on(sbi, list_empty(&en->list));
241	list_del_init(&en->list);
242	spin_unlock(&sbi->extent_lock);
243
244	__detach_extent_node(sbi, et, en);
245}
246
247static struct extent_tree *__grab_extent_tree(struct inode *inode)
248{
249	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
250	struct extent_tree *et;
251	nid_t ino = inode->i_ino;
252
253	mutex_lock(&sbi->extent_tree_lock);
254	et = radix_tree_lookup(&sbi->extent_tree_root, ino);
255	if (!et) {
256		et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
257		f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
258		memset(et, 0, sizeof(struct extent_tree));
259		et->ino = ino;
260		et->root = RB_ROOT;
261		et->cached_en = NULL;
262		rwlock_init(&et->lock);
263		INIT_LIST_HEAD(&et->list);
264		atomic_set(&et->node_cnt, 0);
265		atomic_inc(&sbi->total_ext_tree);
266	} else {
267		atomic_dec(&sbi->total_zombie_tree);
268		list_del_init(&et->list);
269	}
270	mutex_unlock(&sbi->extent_tree_lock);
271
272	/* never died until evict_inode */
273	F2FS_I(inode)->extent_tree = et;
274
275	return et;
276}
277
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
278static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
279				struct extent_tree *et, struct extent_info *ei)
280{
281	struct rb_node **p = &et->root.rb_node;
282	struct extent_node *en;
283
284	en = __attach_extent_node(sbi, et, ei, NULL, p);
285	if (!en)
286		return NULL;
287
288	et->largest = en->ei;
289	et->cached_en = en;
290	return en;
291}
292
293static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
294					struct extent_tree *et)
295{
296	struct rb_node *node, *next;
297	struct extent_node *en;
298	unsigned int count = atomic_read(&et->node_cnt);
299
300	node = rb_first(&et->root);
301	while (node) {
302		next = rb_next(node);
303		en = rb_entry(node, struct extent_node, rb_node);
304		__release_extent_node(sbi, et, en);
305		node = next;
306	}
307
308	return count - atomic_read(&et->node_cnt);
309}
310
311static void __drop_largest_extent(struct inode *inode,
312					pgoff_t fofs, unsigned int len)
313{
314	struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
315
316	if (fofs < largest->fofs + largest->len && fofs + len > largest->fofs) {
317		largest->len = 0;
318		f2fs_mark_inode_dirty_sync(inode, true);
319	}
320}
321
322/* return true, if inode page is changed */
323static bool __f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
324{
325	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
326	struct extent_tree *et;
327	struct extent_node *en;
328	struct extent_info ei;
329
330	if (!f2fs_may_extent_tree(inode)) {
331		/* drop largest extent */
332		if (i_ext && i_ext->len) {
333			i_ext->len = 0;
334			return true;
335		}
336		return false;
337	}
338
339	et = __grab_extent_tree(inode);
340
341	if (!i_ext || !i_ext->len)
342		return false;
343
344	get_extent_info(&ei, i_ext);
 
345
346	write_lock(&et->lock);
347	if (atomic_read(&et->node_cnt))
348		goto out;
349
350	en = __init_extent_tree(sbi, et, &ei);
351	if (en) {
352		spin_lock(&sbi->extent_lock);
353		list_add_tail(&en->list, &sbi->extent_list);
354		spin_unlock(&sbi->extent_lock);
355	}
356out:
357	write_unlock(&et->lock);
358	return false;
359}
360
361bool f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
362{
363	bool ret =  __f2fs_init_extent_tree(inode, i_ext);
364
365	if (!F2FS_I(inode)->extent_tree)
366		set_inode_flag(inode, FI_NO_EXTENT);
367
368	return ret;
369}
370
371static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
372							struct extent_info *ei)
373{
374	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
375	struct extent_tree *et = F2FS_I(inode)->extent_tree;
376	struct extent_node *en;
377	bool ret = false;
378
379	f2fs_bug_on(sbi, !et);
380
381	trace_f2fs_lookup_extent_tree_start(inode, pgofs);
382
383	read_lock(&et->lock);
384
385	if (et->largest.fofs <= pgofs &&
386			et->largest.fofs + et->largest.len > pgofs) {
387		*ei = et->largest;
388		ret = true;
389		stat_inc_largest_node_hit(sbi);
390		goto out;
391	}
392
393	en = (struct extent_node *)__lookup_rb_tree(&et->root,
394				(struct rb_entry *)et->cached_en, pgofs);
395	if (!en)
396		goto out;
397
398	if (en == et->cached_en)
399		stat_inc_cached_node_hit(sbi);
400	else
401		stat_inc_rbtree_node_hit(sbi);
402
403	*ei = en->ei;
404	spin_lock(&sbi->extent_lock);
405	if (!list_empty(&en->list)) {
406		list_move_tail(&en->list, &sbi->extent_list);
407		et->cached_en = en;
408	}
409	spin_unlock(&sbi->extent_lock);
410	ret = true;
411out:
412	stat_inc_total_hit(sbi);
413	read_unlock(&et->lock);
414
415	trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
416	return ret;
417}
418
419static struct extent_node *__try_merge_extent_node(struct inode *inode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
420				struct extent_tree *et, struct extent_info *ei,
421				struct extent_node *prev_ex,
422				struct extent_node *next_ex)
423{
424	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
425	struct extent_node *en = NULL;
426
427	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
428		prev_ex->ei.len += ei->len;
429		ei = &prev_ex->ei;
430		en = prev_ex;
431	}
432
433	if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
 
 
434		next_ex->ei.fofs = ei->fofs;
435		next_ex->ei.blk = ei->blk;
436		next_ex->ei.len += ei->len;
437		if (en)
438			__release_extent_node(sbi, et, prev_ex);
439
440		en = next_ex;
441	}
442
443	if (!en)
444		return NULL;
445
446	__try_update_largest_extent(inode, et, en);
447
448	spin_lock(&sbi->extent_lock);
449	if (!list_empty(&en->list)) {
450		list_move_tail(&en->list, &sbi->extent_list);
451		et->cached_en = en;
452	}
453	spin_unlock(&sbi->extent_lock);
454	return en;
455}
456
457static struct extent_node *__insert_extent_tree(struct inode *inode,
458				struct extent_tree *et, struct extent_info *ei,
459				struct rb_node **insert_p,
460				struct rb_node *insert_parent)
461{
462	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
463	struct rb_node **p;
464	struct rb_node *parent = NULL;
465	struct extent_node *en = NULL;
466
467	if (insert_p && insert_parent) {
468		parent = insert_parent;
469		p = insert_p;
470		goto do_insert;
471	}
472
473	p = __lookup_rb_tree_for_insert(sbi, &et->root, &parent, ei->fofs);
 
 
 
 
 
 
 
 
 
 
474do_insert:
475	en = __attach_extent_node(sbi, et, ei, parent, p);
476	if (!en)
477		return NULL;
478
479	__try_update_largest_extent(inode, et, en);
480
481	/* update in global extent list */
482	spin_lock(&sbi->extent_lock);
483	list_add_tail(&en->list, &sbi->extent_list);
484	et->cached_en = en;
485	spin_unlock(&sbi->extent_lock);
486	return en;
487}
488
489static void f2fs_update_extent_tree_range(struct inode *inode,
490				pgoff_t fofs, block_t blkaddr, unsigned int len)
491{
492	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
493	struct extent_tree *et = F2FS_I(inode)->extent_tree;
494	struct extent_node *en = NULL, *en1 = NULL;
495	struct extent_node *prev_en = NULL, *next_en = NULL;
496	struct extent_info ei, dei, prev;
497	struct rb_node **insert_p = NULL, *insert_parent = NULL;
498	unsigned int end = fofs + len;
499	unsigned int pos = (unsigned int)fofs;
500
501	if (!et)
502		return;
503
504	trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
505
506	write_lock(&et->lock);
507
508	if (is_inode_flag_set(inode, FI_NO_EXTENT)) {
509		write_unlock(&et->lock);
510		return;
511	}
512
513	prev = et->largest;
514	dei.len = 0;
515
516	/*
517	 * drop largest extent before lookup, in case it's already
518	 * been shrunk from extent tree
519	 */
520	__drop_largest_extent(inode, fofs, len);
521
522	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
523	en = (struct extent_node *)__lookup_rb_tree_ret(&et->root,
524					(struct rb_entry *)et->cached_en, fofs,
525					(struct rb_entry **)&prev_en,
526					(struct rb_entry **)&next_en,
527					&insert_p, &insert_parent, false);
528	if (!en)
529		en = next_en;
530
531	/* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
532	while (en && en->ei.fofs < end) {
533		unsigned int org_end;
534		int parts = 0;	/* # of parts current extent split into */
535
536		next_en = en1 = NULL;
537
538		dei = en->ei;
539		org_end = dei.fofs + dei.len;
540		f2fs_bug_on(sbi, pos >= org_end);
541
542		if (pos > dei.fofs &&	pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
543			en->ei.len = pos - en->ei.fofs;
544			prev_en = en;
545			parts = 1;
546		}
547
548		if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
549			if (parts) {
550				set_extent_info(&ei, end,
551						end - dei.fofs + dei.blk,
552						org_end - end);
553				en1 = __insert_extent_tree(inode, et, &ei,
554							NULL, NULL);
555				next_en = en1;
556			} else {
557				en->ei.fofs = end;
558				en->ei.blk += end - dei.fofs;
559				en->ei.len -= end - dei.fofs;
560				next_en = en;
561			}
562			parts++;
563		}
564
565		if (!next_en) {
566			struct rb_node *node = rb_next(&en->rb_node);
567
568			next_en = rb_entry_safe(node, struct extent_node,
569						rb_node);
 
570		}
571
572		if (parts)
573			__try_update_largest_extent(inode, et, en);
574		else
575			__release_extent_node(sbi, et, en);
576
577		/*
578		 * if original extent is split into zero or two parts, extent
579		 * tree has been altered by deletion or insertion, therefore
580		 * invalidate pointers regard to tree.
581		 */
582		if (parts != 1) {
583			insert_p = NULL;
584			insert_parent = NULL;
585		}
586		en = next_en;
587	}
588
589	/* 3. update extent in extent cache */
590	if (blkaddr) {
591
592		set_extent_info(&ei, fofs, blkaddr, len);
593		if (!__try_merge_extent_node(inode, et, &ei, prev_en, next_en))
594			__insert_extent_tree(inode, et, &ei,
595						insert_p, insert_parent);
596
597		/* give up extent_cache, if split and small updates happen */
598		if (dei.len >= 1 &&
599				prev.len < F2FS_MIN_EXTENT_LEN &&
600				et->largest.len < F2FS_MIN_EXTENT_LEN) {
601			__drop_largest_extent(inode, 0, UINT_MAX);
602			set_inode_flag(inode, FI_NO_EXTENT);
603		}
604	}
605
606	if (is_inode_flag_set(inode, FI_NO_EXTENT))
607		__free_extent_tree(sbi, et);
608
609	write_unlock(&et->lock);
 
 
610}
611
612unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
613{
614	struct extent_tree *et, *next;
615	struct extent_node *en;
616	unsigned int node_cnt = 0, tree_cnt = 0;
617	int remained;
618
619	if (!test_opt(sbi, EXTENT_CACHE))
620		return 0;
621
622	if (!atomic_read(&sbi->total_zombie_tree))
623		goto free_node;
624
625	if (!mutex_trylock(&sbi->extent_tree_lock))
626		goto out;
627
628	/* 1. remove unreferenced extent tree */
629	list_for_each_entry_safe(et, next, &sbi->zombie_list, list) {
630		if (atomic_read(&et->node_cnt)) {
631			write_lock(&et->lock);
632			node_cnt += __free_extent_tree(sbi, et);
633			write_unlock(&et->lock);
634		}
635		f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
636		list_del_init(&et->list);
637		radix_tree_delete(&sbi->extent_tree_root, et->ino);
638		kmem_cache_free(extent_tree_slab, et);
639		atomic_dec(&sbi->total_ext_tree);
640		atomic_dec(&sbi->total_zombie_tree);
641		tree_cnt++;
642
643		if (node_cnt + tree_cnt >= nr_shrink)
644			goto unlock_out;
645		cond_resched();
646	}
647	mutex_unlock(&sbi->extent_tree_lock);
648
649free_node:
650	/* 2. remove LRU extent entries */
651	if (!mutex_trylock(&sbi->extent_tree_lock))
652		goto out;
653
654	remained = nr_shrink - (node_cnt + tree_cnt);
655
656	spin_lock(&sbi->extent_lock);
657	for (; remained > 0; remained--) {
658		if (list_empty(&sbi->extent_list))
659			break;
660		en = list_first_entry(&sbi->extent_list,
661					struct extent_node, list);
662		et = en->et;
663		if (!write_trylock(&et->lock)) {
664			/* refresh this extent node's position in extent list */
665			list_move_tail(&en->list, &sbi->extent_list);
666			continue;
667		}
668
669		list_del_init(&en->list);
670		spin_unlock(&sbi->extent_lock);
671
672		__detach_extent_node(sbi, et, en);
673
674		write_unlock(&et->lock);
675		node_cnt++;
676		spin_lock(&sbi->extent_lock);
677	}
678	spin_unlock(&sbi->extent_lock);
679
680unlock_out:
681	mutex_unlock(&sbi->extent_tree_lock);
682out:
683	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt);
684
685	return node_cnt + tree_cnt;
686}
687
688unsigned int f2fs_destroy_extent_node(struct inode *inode)
689{
690	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
691	struct extent_tree *et = F2FS_I(inode)->extent_tree;
692	unsigned int node_cnt = 0;
693
694	if (!et || !atomic_read(&et->node_cnt))
695		return 0;
696
697	write_lock(&et->lock);
698	node_cnt = __free_extent_tree(sbi, et);
699	write_unlock(&et->lock);
700
701	return node_cnt;
702}
703
704void f2fs_drop_extent_tree(struct inode *inode)
705{
706	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
707	struct extent_tree *et = F2FS_I(inode)->extent_tree;
708
709	if (!f2fs_may_extent_tree(inode))
710		return;
711
712	set_inode_flag(inode, FI_NO_EXTENT);
713
714	write_lock(&et->lock);
715	__free_extent_tree(sbi, et);
716	__drop_largest_extent(inode, 0, UINT_MAX);
717	write_unlock(&et->lock);
718}
719
720void f2fs_destroy_extent_tree(struct inode *inode)
721{
722	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
723	struct extent_tree *et = F2FS_I(inode)->extent_tree;
724	unsigned int node_cnt = 0;
725
726	if (!et)
727		return;
728
729	if (inode->i_nlink && !is_bad_inode(inode) &&
730					atomic_read(&et->node_cnt)) {
731		mutex_lock(&sbi->extent_tree_lock);
732		list_add_tail(&et->list, &sbi->zombie_list);
733		atomic_inc(&sbi->total_zombie_tree);
734		mutex_unlock(&sbi->extent_tree_lock);
735		return;
736	}
737
738	/* free all extent info belong to this extent tree */
739	node_cnt = f2fs_destroy_extent_node(inode);
740
741	/* delete extent tree entry in radix tree */
742	mutex_lock(&sbi->extent_tree_lock);
743	f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
744	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
745	kmem_cache_free(extent_tree_slab, et);
746	atomic_dec(&sbi->total_ext_tree);
747	mutex_unlock(&sbi->extent_tree_lock);
748
749	F2FS_I(inode)->extent_tree = NULL;
750
751	trace_f2fs_destroy_extent_tree(inode, node_cnt);
752}
753
754bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
755					struct extent_info *ei)
756{
757	if (!f2fs_may_extent_tree(inode))
758		return false;
759
760	return f2fs_lookup_extent_tree(inode, pgofs, ei);
761}
762
763void f2fs_update_extent_cache(struct dnode_of_data *dn)
764{
765	pgoff_t fofs;
766	block_t blkaddr;
767
768	if (!f2fs_may_extent_tree(dn->inode))
769		return;
770
771	if (dn->data_blkaddr == NEW_ADDR)
772		blkaddr = NULL_ADDR;
773	else
774		blkaddr = dn->data_blkaddr;
775
776	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
777								dn->ofs_in_node;
778	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, 1);
 
 
779}
780
781void f2fs_update_extent_cache_range(struct dnode_of_data *dn,
782				pgoff_t fofs, block_t blkaddr, unsigned int len)
783
784{
785	if (!f2fs_may_extent_tree(dn->inode))
786		return;
787
788	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len);
 
789}
790
791void init_extent_cache_info(struct f2fs_sb_info *sbi)
792{
793	INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
794	mutex_init(&sbi->extent_tree_lock);
795	INIT_LIST_HEAD(&sbi->extent_list);
796	spin_lock_init(&sbi->extent_lock);
797	atomic_set(&sbi->total_ext_tree, 0);
798	INIT_LIST_HEAD(&sbi->zombie_list);
799	atomic_set(&sbi->total_zombie_tree, 0);
800	atomic_set(&sbi->total_ext_node, 0);
801}
802
803int __init create_extent_cache(void)
804{
805	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
806			sizeof(struct extent_tree));
807	if (!extent_tree_slab)
808		return -ENOMEM;
809	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
810			sizeof(struct extent_node));
811	if (!extent_node_slab) {
812		kmem_cache_destroy(extent_tree_slab);
813		return -ENOMEM;
814	}
815	return 0;
816}
817
818void destroy_extent_cache(void)
819{
820	kmem_cache_destroy(extent_node_slab);
821	kmem_cache_destroy(extent_tree_slab);
822}
  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}