| // SPDX-License-Identifier: GPL-2.0 | 
 | /* | 
 |  * f2fs extent cache support | 
 |  * | 
 |  * Copyright (c) 2015 Motorola Mobility | 
 |  * Copyright (c) 2015 Samsung Electronics | 
 |  * Authors: Jaegeuk Kim <jaegeuk@kernel.org> | 
 |  *          Chao Yu <chao2.yu@samsung.com> | 
 |  */ | 
 |  | 
 | #include <linux/fs.h> | 
 | #include <linux/f2fs_fs.h> | 
 |  | 
 | #include "f2fs.h" | 
 | #include "node.h" | 
 | #include <trace/events/f2fs.h> | 
 |  | 
 | static struct rb_entry *__lookup_rb_tree_fast(struct rb_entry *cached_re, | 
 | 							unsigned int ofs) | 
 | { | 
 | 	if (cached_re) { | 
 | 		if (cached_re->ofs <= ofs && | 
 | 				cached_re->ofs + cached_re->len > ofs) { | 
 | 			return cached_re; | 
 | 		} | 
 | 	} | 
 | 	return NULL; | 
 | } | 
 |  | 
 | static struct rb_entry *__lookup_rb_tree_slow(struct rb_root_cached *root, | 
 | 							unsigned int ofs) | 
 | { | 
 | 	struct rb_node *node = root->rb_root.rb_node; | 
 | 	struct rb_entry *re; | 
 |  | 
 | 	while (node) { | 
 | 		re = rb_entry(node, struct rb_entry, rb_node); | 
 |  | 
 | 		if (ofs < re->ofs) | 
 | 			node = node->rb_left; | 
 | 		else if (ofs >= re->ofs + re->len) | 
 | 			node = node->rb_right; | 
 | 		else | 
 | 			return re; | 
 | 	} | 
 | 	return NULL; | 
 | } | 
 |  | 
 | struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root, | 
 | 				struct rb_entry *cached_re, unsigned int ofs) | 
 | { | 
 | 	struct rb_entry *re; | 
 |  | 
 | 	re = __lookup_rb_tree_fast(cached_re, ofs); | 
 | 	if (!re) | 
 | 		return __lookup_rb_tree_slow(root, ofs); | 
 |  | 
 | 	return re; | 
 | } | 
 |  | 
 | struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi, | 
 | 				struct rb_root_cached *root, | 
 | 				struct rb_node **parent, | 
 | 				unsigned int ofs, bool *leftmost) | 
 | { | 
 | 	struct rb_node **p = &root->rb_root.rb_node; | 
 | 	struct rb_entry *re; | 
 |  | 
 | 	while (*p) { | 
 | 		*parent = *p; | 
 | 		re = rb_entry(*parent, struct rb_entry, rb_node); | 
 |  | 
 | 		if (ofs < re->ofs) { | 
 | 			p = &(*p)->rb_left; | 
 | 		} else if (ofs >= re->ofs + re->len) { | 
 | 			p = &(*p)->rb_right; | 
 | 			*leftmost = false; | 
 | 		} else { | 
 | 			f2fs_bug_on(sbi, 1); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return p; | 
 | } | 
 |  | 
 | /* | 
 |  * lookup rb entry in position of @ofs in rb-tree, | 
 |  * if hit, return the entry, otherwise, return NULL | 
 |  * @prev_ex: extent before ofs | 
 |  * @next_ex: extent after ofs | 
 |  * @insert_p: insert point for new extent at ofs | 
 |  * in order to simpfy the insertion after. | 
 |  * tree must stay unchanged between lookup and insertion. | 
 |  */ | 
 | struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root, | 
 | 				struct rb_entry *cached_re, | 
 | 				unsigned int ofs, | 
 | 				struct rb_entry **prev_entry, | 
 | 				struct rb_entry **next_entry, | 
 | 				struct rb_node ***insert_p, | 
 | 				struct rb_node **insert_parent, | 
 | 				bool force, bool *leftmost) | 
 | { | 
 | 	struct rb_node **pnode = &root->rb_root.rb_node; | 
 | 	struct rb_node *parent = NULL, *tmp_node; | 
 | 	struct rb_entry *re = cached_re; | 
 |  | 
 | 	*insert_p = NULL; | 
 | 	*insert_parent = NULL; | 
 | 	*prev_entry = NULL; | 
 | 	*next_entry = NULL; | 
 |  | 
 | 	if (RB_EMPTY_ROOT(&root->rb_root)) | 
 | 		return NULL; | 
 |  | 
 | 	if (re) { | 
 | 		if (re->ofs <= ofs && re->ofs + re->len > ofs) | 
 | 			goto lookup_neighbors; | 
 | 	} | 
 |  | 
 | 	if (leftmost) | 
 | 		*leftmost = true; | 
 |  | 
 | 	while (*pnode) { | 
 | 		parent = *pnode; | 
 | 		re = rb_entry(*pnode, struct rb_entry, rb_node); | 
 |  | 
 | 		if (ofs < re->ofs) { | 
 | 			pnode = &(*pnode)->rb_left; | 
 | 		} else if (ofs >= re->ofs + re->len) { | 
 | 			pnode = &(*pnode)->rb_right; | 
 | 			if (leftmost) | 
 | 				*leftmost = false; | 
 | 		} else { | 
 | 			goto lookup_neighbors; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	*insert_p = pnode; | 
 | 	*insert_parent = parent; | 
 |  | 
 | 	re = rb_entry(parent, struct rb_entry, rb_node); | 
 | 	tmp_node = parent; | 
 | 	if (parent && ofs > re->ofs) | 
 | 		tmp_node = rb_next(parent); | 
 | 	*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node); | 
 |  | 
 | 	tmp_node = parent; | 
 | 	if (parent && ofs < re->ofs) | 
 | 		tmp_node = rb_prev(parent); | 
 | 	*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node); | 
 | 	return NULL; | 
 |  | 
 | lookup_neighbors: | 
 | 	if (ofs == re->ofs || force) { | 
 | 		/* lookup prev node for merging backward later */ | 
 | 		tmp_node = rb_prev(&re->rb_node); | 
 | 		*prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node); | 
 | 	} | 
 | 	if (ofs == re->ofs + re->len - 1 || force) { | 
 | 		/* lookup next node for merging frontward later */ | 
 | 		tmp_node = rb_next(&re->rb_node); | 
 | 		*next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node); | 
 | 	} | 
 | 	return re; | 
 | } | 
 |  | 
 | bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi, | 
 | 						struct rb_root_cached *root) | 
 | { | 
 | #ifdef CONFIG_F2FS_CHECK_FS | 
 | 	struct rb_node *cur = rb_first_cached(root), *next; | 
 | 	struct rb_entry *cur_re, *next_re; | 
 |  | 
 | 	if (!cur) | 
 | 		return true; | 
 |  | 
 | 	while (cur) { | 
 | 		next = rb_next(cur); | 
 | 		if (!next) | 
 | 			return true; | 
 |  | 
 | 		cur_re = rb_entry(cur, struct rb_entry, rb_node); | 
 | 		next_re = rb_entry(next, struct rb_entry, rb_node); | 
 |  | 
 | 		if (cur_re->ofs + cur_re->len > next_re->ofs) { | 
 | 			f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)", | 
 | 				  cur_re->ofs, cur_re->len, | 
 | 				  next_re->ofs, next_re->len); | 
 | 			return false; | 
 | 		} | 
 |  | 
 | 		cur = next; | 
 | 	} | 
 | #endif | 
 | 	return true; | 
 | } | 
 |  | 
 | static struct kmem_cache *extent_tree_slab; | 
 | static struct kmem_cache *extent_node_slab; | 
 |  | 
 | static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi, | 
 | 				struct extent_tree *et, struct extent_info *ei, | 
 | 				struct rb_node *parent, struct rb_node **p, | 
 | 				bool leftmost) | 
 | { | 
 | 	struct extent_node *en; | 
 |  | 
 | 	en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC); | 
 | 	if (!en) | 
 | 		return NULL; | 
 |  | 
 | 	en->ei = *ei; | 
 | 	INIT_LIST_HEAD(&en->list); | 
 | 	en->et = et; | 
 |  | 
 | 	rb_link_node(&en->rb_node, parent, p); | 
 | 	rb_insert_color_cached(&en->rb_node, &et->root, leftmost); | 
 | 	atomic_inc(&et->node_cnt); | 
 | 	atomic_inc(&sbi->total_ext_node); | 
 | 	return en; | 
 | } | 
 |  | 
 | static void __detach_extent_node(struct f2fs_sb_info *sbi, | 
 | 				struct extent_tree *et, struct extent_node *en) | 
 | { | 
 | 	rb_erase_cached(&en->rb_node, &et->root); | 
 | 	atomic_dec(&et->node_cnt); | 
 | 	atomic_dec(&sbi->total_ext_node); | 
 |  | 
 | 	if (et->cached_en == en) | 
 | 		et->cached_en = NULL; | 
 | 	kmem_cache_free(extent_node_slab, en); | 
 | } | 
 |  | 
 | /* | 
 |  * Flow to release an extent_node: | 
 |  * 1. list_del_init | 
 |  * 2. __detach_extent_node | 
 |  * 3. kmem_cache_free. | 
 |  */ | 
 | static void __release_extent_node(struct f2fs_sb_info *sbi, | 
 | 			struct extent_tree *et, struct extent_node *en) | 
 | { | 
 | 	spin_lock(&sbi->extent_lock); | 
 | 	f2fs_bug_on(sbi, list_empty(&en->list)); | 
 | 	list_del_init(&en->list); | 
 | 	spin_unlock(&sbi->extent_lock); | 
 |  | 
 | 	__detach_extent_node(sbi, et, en); | 
 | } | 
 |  | 
 | static struct extent_tree *__grab_extent_tree(struct inode *inode) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et; | 
 | 	nid_t ino = inode->i_ino; | 
 |  | 
 | 	mutex_lock(&sbi->extent_tree_lock); | 
 | 	et = radix_tree_lookup(&sbi->extent_tree_root, ino); | 
 | 	if (!et) { | 
 | 		et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS); | 
 | 		f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et); | 
 | 		memset(et, 0, sizeof(struct extent_tree)); | 
 | 		et->ino = ino; | 
 | 		et->root = RB_ROOT_CACHED; | 
 | 		et->cached_en = NULL; | 
 | 		rwlock_init(&et->lock); | 
 | 		INIT_LIST_HEAD(&et->list); | 
 | 		atomic_set(&et->node_cnt, 0); | 
 | 		atomic_inc(&sbi->total_ext_tree); | 
 | 	} else { | 
 | 		atomic_dec(&sbi->total_zombie_tree); | 
 | 		list_del_init(&et->list); | 
 | 	} | 
 | 	mutex_unlock(&sbi->extent_tree_lock); | 
 |  | 
 | 	/* never died until evict_inode */ | 
 | 	F2FS_I(inode)->extent_tree = et; | 
 |  | 
 | 	return et; | 
 | } | 
 |  | 
 | static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi, | 
 | 				struct extent_tree *et, struct extent_info *ei) | 
 | { | 
 | 	struct rb_node **p = &et->root.rb_root.rb_node; | 
 | 	struct extent_node *en; | 
 |  | 
 | 	en = __attach_extent_node(sbi, et, ei, NULL, p, true); | 
 | 	if (!en) | 
 | 		return NULL; | 
 |  | 
 | 	et->largest = en->ei; | 
 | 	et->cached_en = en; | 
 | 	return en; | 
 | } | 
 |  | 
 | static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi, | 
 | 					struct extent_tree *et) | 
 | { | 
 | 	struct rb_node *node, *next; | 
 | 	struct extent_node *en; | 
 | 	unsigned int count = atomic_read(&et->node_cnt); | 
 |  | 
 | 	node = rb_first_cached(&et->root); | 
 | 	while (node) { | 
 | 		next = rb_next(node); | 
 | 		en = rb_entry(node, struct extent_node, rb_node); | 
 | 		__release_extent_node(sbi, et, en); | 
 | 		node = next; | 
 | 	} | 
 |  | 
 | 	return count - atomic_read(&et->node_cnt); | 
 | } | 
 |  | 
 | static void __drop_largest_extent(struct extent_tree *et, | 
 | 					pgoff_t fofs, unsigned int len) | 
 | { | 
 | 	if (fofs < et->largest.fofs + et->largest.len && | 
 | 			fofs + len > et->largest.fofs) { | 
 | 		et->largest.len = 0; | 
 | 		et->largest_updated = true; | 
 | 	} | 
 | } | 
 |  | 
 | /* return true, if inode page is changed */ | 
 | static bool __f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et; | 
 | 	struct extent_node *en; | 
 | 	struct extent_info ei; | 
 |  | 
 | 	if (!f2fs_may_extent_tree(inode)) { | 
 | 		/* drop largest extent */ | 
 | 		if (i_ext && i_ext->len) { | 
 | 			i_ext->len = 0; | 
 | 			return true; | 
 | 		} | 
 | 		return false; | 
 | 	} | 
 |  | 
 | 	et = __grab_extent_tree(inode); | 
 |  | 
 | 	if (!i_ext || !i_ext->len) | 
 | 		return false; | 
 |  | 
 | 	get_extent_info(&ei, i_ext); | 
 |  | 
 | 	write_lock(&et->lock); | 
 | 	if (atomic_read(&et->node_cnt)) | 
 | 		goto out; | 
 |  | 
 | 	en = __init_extent_tree(sbi, et, &ei); | 
 | 	if (en) { | 
 | 		spin_lock(&sbi->extent_lock); | 
 | 		list_add_tail(&en->list, &sbi->extent_list); | 
 | 		spin_unlock(&sbi->extent_lock); | 
 | 	} | 
 | out: | 
 | 	write_unlock(&et->lock); | 
 | 	return false; | 
 | } | 
 |  | 
 | bool f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext) | 
 | { | 
 | 	bool ret =  __f2fs_init_extent_tree(inode, i_ext); | 
 |  | 
 | 	if (!F2FS_I(inode)->extent_tree) | 
 | 		set_inode_flag(inode, FI_NO_EXTENT); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs, | 
 | 							struct extent_info *ei) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et = F2FS_I(inode)->extent_tree; | 
 | 	struct extent_node *en; | 
 | 	bool ret = false; | 
 |  | 
 | 	f2fs_bug_on(sbi, !et); | 
 |  | 
 | 	trace_f2fs_lookup_extent_tree_start(inode, pgofs); | 
 |  | 
 | 	read_lock(&et->lock); | 
 |  | 
 | 	if (et->largest.fofs <= pgofs && | 
 | 			et->largest.fofs + et->largest.len > pgofs) { | 
 | 		*ei = et->largest; | 
 | 		ret = true; | 
 | 		stat_inc_largest_node_hit(sbi); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	en = (struct extent_node *)f2fs_lookup_rb_tree(&et->root, | 
 | 				(struct rb_entry *)et->cached_en, pgofs); | 
 | 	if (!en) | 
 | 		goto out; | 
 |  | 
 | 	if (en == et->cached_en) | 
 | 		stat_inc_cached_node_hit(sbi); | 
 | 	else | 
 | 		stat_inc_rbtree_node_hit(sbi); | 
 |  | 
 | 	*ei = en->ei; | 
 | 	spin_lock(&sbi->extent_lock); | 
 | 	if (!list_empty(&en->list)) { | 
 | 		list_move_tail(&en->list, &sbi->extent_list); | 
 | 		et->cached_en = en; | 
 | 	} | 
 | 	spin_unlock(&sbi->extent_lock); | 
 | 	ret = true; | 
 | out: | 
 | 	stat_inc_total_hit(sbi); | 
 | 	read_unlock(&et->lock); | 
 |  | 
 | 	trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei); | 
 | 	return ret; | 
 | } | 
 |  | 
 | static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi, | 
 | 				struct extent_tree *et, struct extent_info *ei, | 
 | 				struct extent_node *prev_ex, | 
 | 				struct extent_node *next_ex) | 
 | { | 
 | 	struct extent_node *en = NULL; | 
 |  | 
 | 	if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) { | 
 | 		prev_ex->ei.len += ei->len; | 
 | 		ei = &prev_ex->ei; | 
 | 		en = prev_ex; | 
 | 	} | 
 |  | 
 | 	if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) { | 
 | 		next_ex->ei.fofs = ei->fofs; | 
 | 		next_ex->ei.blk = ei->blk; | 
 | 		next_ex->ei.len += ei->len; | 
 | 		if (en) | 
 | 			__release_extent_node(sbi, et, prev_ex); | 
 |  | 
 | 		en = next_ex; | 
 | 	} | 
 |  | 
 | 	if (!en) | 
 | 		return NULL; | 
 |  | 
 | 	__try_update_largest_extent(et, en); | 
 |  | 
 | 	spin_lock(&sbi->extent_lock); | 
 | 	if (!list_empty(&en->list)) { | 
 | 		list_move_tail(&en->list, &sbi->extent_list); | 
 | 		et->cached_en = en; | 
 | 	} | 
 | 	spin_unlock(&sbi->extent_lock); | 
 | 	return en; | 
 | } | 
 |  | 
 | static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi, | 
 | 				struct extent_tree *et, struct extent_info *ei, | 
 | 				struct rb_node **insert_p, | 
 | 				struct rb_node *insert_parent, | 
 | 				bool leftmost) | 
 | { | 
 | 	struct rb_node **p; | 
 | 	struct rb_node *parent = NULL; | 
 | 	struct extent_node *en = NULL; | 
 |  | 
 | 	if (insert_p && insert_parent) { | 
 | 		parent = insert_parent; | 
 | 		p = insert_p; | 
 | 		goto do_insert; | 
 | 	} | 
 |  | 
 | 	leftmost = true; | 
 |  | 
 | 	p = f2fs_lookup_rb_tree_for_insert(sbi, &et->root, &parent, | 
 | 						ei->fofs, &leftmost); | 
 | do_insert: | 
 | 	en = __attach_extent_node(sbi, et, ei, parent, p, leftmost); | 
 | 	if (!en) | 
 | 		return NULL; | 
 |  | 
 | 	__try_update_largest_extent(et, en); | 
 |  | 
 | 	/* update in global extent list */ | 
 | 	spin_lock(&sbi->extent_lock); | 
 | 	list_add_tail(&en->list, &sbi->extent_list); | 
 | 	et->cached_en = en; | 
 | 	spin_unlock(&sbi->extent_lock); | 
 | 	return en; | 
 | } | 
 |  | 
 | static void f2fs_update_extent_tree_range(struct inode *inode, | 
 | 				pgoff_t fofs, block_t blkaddr, unsigned int len) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et = F2FS_I(inode)->extent_tree; | 
 | 	struct extent_node *en = NULL, *en1 = NULL; | 
 | 	struct extent_node *prev_en = NULL, *next_en = NULL; | 
 | 	struct extent_info ei, dei, prev; | 
 | 	struct rb_node **insert_p = NULL, *insert_parent = NULL; | 
 | 	unsigned int end = fofs + len; | 
 | 	unsigned int pos = (unsigned int)fofs; | 
 | 	bool updated = false; | 
 | 	bool leftmost = false; | 
 |  | 
 | 	if (!et) | 
 | 		return; | 
 |  | 
 | 	trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len); | 
 |  | 
 | 	write_lock(&et->lock); | 
 |  | 
 | 	if (is_inode_flag_set(inode, FI_NO_EXTENT)) { | 
 | 		write_unlock(&et->lock); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	prev = et->largest; | 
 | 	dei.len = 0; | 
 |  | 
 | 	/* | 
 | 	 * drop largest extent before lookup, in case it's already | 
 | 	 * been shrunk from extent tree | 
 | 	 */ | 
 | 	__drop_largest_extent(et, fofs, len); | 
 |  | 
 | 	/* 1. lookup first extent node in range [fofs, fofs + len - 1] */ | 
 | 	en = (struct extent_node *)f2fs_lookup_rb_tree_ret(&et->root, | 
 | 					(struct rb_entry *)et->cached_en, fofs, | 
 | 					(struct rb_entry **)&prev_en, | 
 | 					(struct rb_entry **)&next_en, | 
 | 					&insert_p, &insert_parent, false, | 
 | 					&leftmost); | 
 | 	if (!en) | 
 | 		en = next_en; | 
 |  | 
 | 	/* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */ | 
 | 	while (en && en->ei.fofs < end) { | 
 | 		unsigned int org_end; | 
 | 		int parts = 0;	/* # of parts current extent split into */ | 
 |  | 
 | 		next_en = en1 = NULL; | 
 |  | 
 | 		dei = en->ei; | 
 | 		org_end = dei.fofs + dei.len; | 
 | 		f2fs_bug_on(sbi, pos >= org_end); | 
 |  | 
 | 		if (pos > dei.fofs &&	pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) { | 
 | 			en->ei.len = pos - en->ei.fofs; | 
 | 			prev_en = en; | 
 | 			parts = 1; | 
 | 		} | 
 |  | 
 | 		if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) { | 
 | 			if (parts) { | 
 | 				set_extent_info(&ei, end, | 
 | 						end - dei.fofs + dei.blk, | 
 | 						org_end - end); | 
 | 				en1 = __insert_extent_tree(sbi, et, &ei, | 
 | 							NULL, NULL, true); | 
 | 				next_en = en1; | 
 | 			} else { | 
 | 				en->ei.fofs = end; | 
 | 				en->ei.blk += end - dei.fofs; | 
 | 				en->ei.len -= end - dei.fofs; | 
 | 				next_en = en; | 
 | 			} | 
 | 			parts++; | 
 | 		} | 
 |  | 
 | 		if (!next_en) { | 
 | 			struct rb_node *node = rb_next(&en->rb_node); | 
 |  | 
 | 			next_en = rb_entry_safe(node, struct extent_node, | 
 | 						rb_node); | 
 | 		} | 
 |  | 
 | 		if (parts) | 
 | 			__try_update_largest_extent(et, en); | 
 | 		else | 
 | 			__release_extent_node(sbi, et, en); | 
 |  | 
 | 		/* | 
 | 		 * if original extent is split into zero or two parts, extent | 
 | 		 * tree has been altered by deletion or insertion, therefore | 
 | 		 * invalidate pointers regard to tree. | 
 | 		 */ | 
 | 		if (parts != 1) { | 
 | 			insert_p = NULL; | 
 | 			insert_parent = NULL; | 
 | 		} | 
 | 		en = next_en; | 
 | 	} | 
 |  | 
 | 	/* 3. update extent in extent cache */ | 
 | 	if (blkaddr) { | 
 |  | 
 | 		set_extent_info(&ei, fofs, blkaddr, len); | 
 | 		if (!__try_merge_extent_node(sbi, et, &ei, prev_en, next_en)) | 
 | 			__insert_extent_tree(sbi, et, &ei, | 
 | 					insert_p, insert_parent, leftmost); | 
 |  | 
 | 		/* give up extent_cache, if split and small updates happen */ | 
 | 		if (dei.len >= 1 && | 
 | 				prev.len < F2FS_MIN_EXTENT_LEN && | 
 | 				et->largest.len < F2FS_MIN_EXTENT_LEN) { | 
 | 			et->largest.len = 0; | 
 | 			et->largest_updated = true; | 
 | 			set_inode_flag(inode, FI_NO_EXTENT); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (is_inode_flag_set(inode, FI_NO_EXTENT)) | 
 | 		__free_extent_tree(sbi, et); | 
 |  | 
 | 	if (et->largest_updated) { | 
 | 		et->largest_updated = false; | 
 | 		updated = true; | 
 | 	} | 
 |  | 
 | 	write_unlock(&et->lock); | 
 |  | 
 | 	if (updated) | 
 | 		f2fs_mark_inode_dirty_sync(inode, true); | 
 | } | 
 |  | 
 | unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink) | 
 | { | 
 | 	struct extent_tree *et, *next; | 
 | 	struct extent_node *en; | 
 | 	unsigned int node_cnt = 0, tree_cnt = 0; | 
 | 	int remained; | 
 |  | 
 | 	if (!test_opt(sbi, EXTENT_CACHE)) | 
 | 		return 0; | 
 |  | 
 | 	if (!atomic_read(&sbi->total_zombie_tree)) | 
 | 		goto free_node; | 
 |  | 
 | 	if (!mutex_trylock(&sbi->extent_tree_lock)) | 
 | 		goto out; | 
 |  | 
 | 	/* 1. remove unreferenced extent tree */ | 
 | 	list_for_each_entry_safe(et, next, &sbi->zombie_list, list) { | 
 | 		if (atomic_read(&et->node_cnt)) { | 
 | 			write_lock(&et->lock); | 
 | 			node_cnt += __free_extent_tree(sbi, et); | 
 | 			write_unlock(&et->lock); | 
 | 		} | 
 | 		f2fs_bug_on(sbi, atomic_read(&et->node_cnt)); | 
 | 		list_del_init(&et->list); | 
 | 		radix_tree_delete(&sbi->extent_tree_root, et->ino); | 
 | 		kmem_cache_free(extent_tree_slab, et); | 
 | 		atomic_dec(&sbi->total_ext_tree); | 
 | 		atomic_dec(&sbi->total_zombie_tree); | 
 | 		tree_cnt++; | 
 |  | 
 | 		if (node_cnt + tree_cnt >= nr_shrink) | 
 | 			goto unlock_out; | 
 | 		cond_resched(); | 
 | 	} | 
 | 	mutex_unlock(&sbi->extent_tree_lock); | 
 |  | 
 | free_node: | 
 | 	/* 2. remove LRU extent entries */ | 
 | 	if (!mutex_trylock(&sbi->extent_tree_lock)) | 
 | 		goto out; | 
 |  | 
 | 	remained = nr_shrink - (node_cnt + tree_cnt); | 
 |  | 
 | 	spin_lock(&sbi->extent_lock); | 
 | 	for (; remained > 0; remained--) { | 
 | 		if (list_empty(&sbi->extent_list)) | 
 | 			break; | 
 | 		en = list_first_entry(&sbi->extent_list, | 
 | 					struct extent_node, list); | 
 | 		et = en->et; | 
 | 		if (!write_trylock(&et->lock)) { | 
 | 			/* refresh this extent node's position in extent list */ | 
 | 			list_move_tail(&en->list, &sbi->extent_list); | 
 | 			continue; | 
 | 		} | 
 |  | 
 | 		list_del_init(&en->list); | 
 | 		spin_unlock(&sbi->extent_lock); | 
 |  | 
 | 		__detach_extent_node(sbi, et, en); | 
 |  | 
 | 		write_unlock(&et->lock); | 
 | 		node_cnt++; | 
 | 		spin_lock(&sbi->extent_lock); | 
 | 	} | 
 | 	spin_unlock(&sbi->extent_lock); | 
 |  | 
 | unlock_out: | 
 | 	mutex_unlock(&sbi->extent_tree_lock); | 
 | out: | 
 | 	trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt); | 
 |  | 
 | 	return node_cnt + tree_cnt; | 
 | } | 
 |  | 
 | unsigned int f2fs_destroy_extent_node(struct inode *inode) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et = F2FS_I(inode)->extent_tree; | 
 | 	unsigned int node_cnt = 0; | 
 |  | 
 | 	if (!et || !atomic_read(&et->node_cnt)) | 
 | 		return 0; | 
 |  | 
 | 	write_lock(&et->lock); | 
 | 	node_cnt = __free_extent_tree(sbi, et); | 
 | 	write_unlock(&et->lock); | 
 |  | 
 | 	return node_cnt; | 
 | } | 
 |  | 
 | void f2fs_drop_extent_tree(struct inode *inode) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et = F2FS_I(inode)->extent_tree; | 
 | 	bool updated = false; | 
 |  | 
 | 	if (!f2fs_may_extent_tree(inode)) | 
 | 		return; | 
 |  | 
 | 	set_inode_flag(inode, FI_NO_EXTENT); | 
 |  | 
 | 	write_lock(&et->lock); | 
 | 	__free_extent_tree(sbi, et); | 
 | 	if (et->largest.len) { | 
 | 		et->largest.len = 0; | 
 | 		updated = true; | 
 | 	} | 
 | 	write_unlock(&et->lock); | 
 | 	if (updated) | 
 | 		f2fs_mark_inode_dirty_sync(inode, true); | 
 | } | 
 |  | 
 | void f2fs_destroy_extent_tree(struct inode *inode) | 
 | { | 
 | 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode); | 
 | 	struct extent_tree *et = F2FS_I(inode)->extent_tree; | 
 | 	unsigned int node_cnt = 0; | 
 |  | 
 | 	if (!et) | 
 | 		return; | 
 |  | 
 | 	if (inode->i_nlink && !is_bad_inode(inode) && | 
 | 					atomic_read(&et->node_cnt)) { | 
 | 		mutex_lock(&sbi->extent_tree_lock); | 
 | 		list_add_tail(&et->list, &sbi->zombie_list); | 
 | 		atomic_inc(&sbi->total_zombie_tree); | 
 | 		mutex_unlock(&sbi->extent_tree_lock); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	/* free all extent info belong to this extent tree */ | 
 | 	node_cnt = f2fs_destroy_extent_node(inode); | 
 |  | 
 | 	/* delete extent tree entry in radix tree */ | 
 | 	mutex_lock(&sbi->extent_tree_lock); | 
 | 	f2fs_bug_on(sbi, atomic_read(&et->node_cnt)); | 
 | 	radix_tree_delete(&sbi->extent_tree_root, inode->i_ino); | 
 | 	kmem_cache_free(extent_tree_slab, et); | 
 | 	atomic_dec(&sbi->total_ext_tree); | 
 | 	mutex_unlock(&sbi->extent_tree_lock); | 
 |  | 
 | 	F2FS_I(inode)->extent_tree = NULL; | 
 |  | 
 | 	trace_f2fs_destroy_extent_tree(inode, node_cnt); | 
 | } | 
 |  | 
 | bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs, | 
 | 					struct extent_info *ei) | 
 | { | 
 | 	if (!f2fs_may_extent_tree(inode)) | 
 | 		return false; | 
 |  | 
 | 	return f2fs_lookup_extent_tree(inode, pgofs, ei); | 
 | } | 
 |  | 
 | void f2fs_update_extent_cache(struct dnode_of_data *dn) | 
 | { | 
 | 	pgoff_t fofs; | 
 | 	block_t blkaddr; | 
 |  | 
 | 	if (!f2fs_may_extent_tree(dn->inode)) | 
 | 		return; | 
 |  | 
 | 	if (dn->data_blkaddr == NEW_ADDR) | 
 | 		blkaddr = NULL_ADDR; | 
 | 	else | 
 | 		blkaddr = dn->data_blkaddr; | 
 |  | 
 | 	fofs = f2fs_start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) + | 
 | 								dn->ofs_in_node; | 
 | 	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, 1); | 
 | } | 
 |  | 
 | void f2fs_update_extent_cache_range(struct dnode_of_data *dn, | 
 | 				pgoff_t fofs, block_t blkaddr, unsigned int len) | 
 |  | 
 | { | 
 | 	if (!f2fs_may_extent_tree(dn->inode)) | 
 | 		return; | 
 |  | 
 | 	f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len); | 
 | } | 
 |  | 
 | void f2fs_init_extent_cache_info(struct f2fs_sb_info *sbi) | 
 | { | 
 | 	INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO); | 
 | 	mutex_init(&sbi->extent_tree_lock); | 
 | 	INIT_LIST_HEAD(&sbi->extent_list); | 
 | 	spin_lock_init(&sbi->extent_lock); | 
 | 	atomic_set(&sbi->total_ext_tree, 0); | 
 | 	INIT_LIST_HEAD(&sbi->zombie_list); | 
 | 	atomic_set(&sbi->total_zombie_tree, 0); | 
 | 	atomic_set(&sbi->total_ext_node, 0); | 
 | } | 
 |  | 
 | int __init f2fs_create_extent_cache(void) | 
 | { | 
 | 	extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree", | 
 | 			sizeof(struct extent_tree)); | 
 | 	if (!extent_tree_slab) | 
 | 		return -ENOMEM; | 
 | 	extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node", | 
 | 			sizeof(struct extent_node)); | 
 | 	if (!extent_node_slab) { | 
 | 		kmem_cache_destroy(extent_tree_slab); | 
 | 		return -ENOMEM; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | void f2fs_destroy_extent_cache(void) | 
 | { | 
 | 	kmem_cache_destroy(extent_node_slab); | 
 | 	kmem_cache_destroy(extent_tree_slab); | 
 | } |