2 * f2fs extent cache support
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>
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.
15 #include <linux/f2fs_fs.h>
19 #include <trace/events/f2fs.h>
21 static struct kmem_cache *extent_tree_slab;
22 static struct kmem_cache *extent_node_slab;
24 static 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)
28 struct extent_node *en;
30 en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
35 INIT_LIST_HEAD(&en->list);
37 rb_link_node(&en->rb_node, parent, p);
38 rb_insert_color(&en->rb_node, &et->root);
40 atomic_inc(&sbi->total_ext_node);
44 static void __detach_extent_node(struct f2fs_sb_info *sbi,
45 struct extent_tree *et, struct extent_node *en)
47 rb_erase(&en->rb_node, &et->root);
49 atomic_dec(&sbi->total_ext_node);
51 if (et->cached_en == en)
55 static struct extent_tree *__grab_extent_tree(struct inode *inode)
57 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
58 struct extent_tree *et;
59 nid_t ino = inode->i_ino;
61 down_write(&sbi->extent_tree_lock);
62 et = radix_tree_lookup(&sbi->extent_tree_root, ino);
64 et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
65 f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
66 memset(et, 0, sizeof(struct extent_tree));
70 rwlock_init(&et->lock);
71 atomic_set(&et->refcount, 0);
73 sbi->total_ext_tree++;
75 atomic_inc(&et->refcount);
76 up_write(&sbi->extent_tree_lock);
78 /* never died until evict_inode */
79 F2FS_I(inode)->extent_tree = et;
84 static struct extent_node *__lookup_extent_tree(struct f2fs_sb_info *sbi,
85 struct extent_tree *et, unsigned int fofs)
87 struct rb_node *node = et->root.rb_node;
88 struct extent_node *en = et->cached_en;
91 struct extent_info *cei = &en->ei;
93 if (cei->fofs <= fofs && cei->fofs + cei->len > fofs) {
94 stat_inc_cached_node_hit(sbi);
100 en = rb_entry(node, struct extent_node, rb_node);
102 if (fofs < en->ei.fofs) {
103 node = node->rb_left;
104 } else if (fofs >= en->ei.fofs + en->ei.len) {
105 node = node->rb_right;
107 stat_inc_rbtree_node_hit(sbi);
114 static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
115 struct extent_tree *et, struct extent_info *ei)
117 struct rb_node **p = &et->root.rb_node;
118 struct extent_node *en;
120 en = __attach_extent_node(sbi, et, ei, NULL, p);
124 et->largest = en->ei;
129 static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
130 struct extent_tree *et, bool free_all)
132 struct rb_node *node, *next;
133 struct extent_node *en;
134 unsigned int count = et->count;
136 node = rb_first(&et->root);
138 next = rb_next(node);
139 en = rb_entry(node, struct extent_node, rb_node);
142 spin_lock(&sbi->extent_lock);
143 if (!list_empty(&en->list))
144 list_del_init(&en->list);
145 spin_unlock(&sbi->extent_lock);
148 if (free_all || list_empty(&en->list)) {
149 __detach_extent_node(sbi, et, en);
150 kmem_cache_free(extent_node_slab, en);
155 return count - et->count;
158 static void __drop_largest_extent(struct inode *inode,
159 pgoff_t fofs, unsigned int len)
161 struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
163 if (fofs < largest->fofs + largest->len && fofs + len > largest->fofs)
167 void f2fs_drop_largest_extent(struct inode *inode, pgoff_t fofs)
169 if (!f2fs_may_extent_tree(inode))
172 __drop_largest_extent(inode, fofs, 1);
175 static void __f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
177 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
178 struct extent_tree *et;
179 struct extent_node *en;
180 struct extent_info ei;
182 if (!f2fs_may_extent_tree(inode))
185 et = __grab_extent_tree(inode);
187 if (!i_ext || le32_to_cpu(i_ext->len) < F2FS_MIN_EXTENT_LEN)
190 set_extent_info(&ei, le32_to_cpu(i_ext->fofs),
191 le32_to_cpu(i_ext->blk), le32_to_cpu(i_ext->len));
193 write_lock(&et->lock);
197 en = __init_extent_tree(sbi, et, &ei);
199 spin_lock(&sbi->extent_lock);
200 list_add_tail(&en->list, &sbi->extent_list);
201 spin_unlock(&sbi->extent_lock);
204 write_unlock(&et->lock);
207 void f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
209 __f2fs_init_extent_tree(inode, i_ext);
211 if (!F2FS_I(inode)->extent_tree)
212 set_inode_flag(F2FS_I(inode), FI_NO_EXTENT);
215 static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
216 struct extent_info *ei)
218 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
219 struct extent_tree *et = F2FS_I(inode)->extent_tree;
220 struct extent_node *en;
223 f2fs_bug_on(sbi, !et);
225 trace_f2fs_lookup_extent_tree_start(inode, pgofs);
227 read_lock(&et->lock);
229 if (et->largest.fofs <= pgofs &&
230 et->largest.fofs + et->largest.len > pgofs) {
233 stat_inc_largest_node_hit(sbi);
237 en = __lookup_extent_tree(sbi, et, pgofs);
240 spin_lock(&sbi->extent_lock);
241 if (!list_empty(&en->list))
242 list_move_tail(&en->list, &sbi->extent_list);
244 spin_unlock(&sbi->extent_lock);
248 stat_inc_total_hit(sbi);
249 read_unlock(&et->lock);
251 trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
257 * lookup extent at @fofs, if hit, return the extent
258 * if not, return NULL and
259 * @prev_ex: extent before fofs
260 * @next_ex: extent after fofs
261 * @insert_p: insert point for new extent at fofs
262 * in order to simpfy the insertion after.
263 * tree must stay unchanged between lookup and insertion.
265 static struct extent_node *__lookup_extent_tree_ret(struct extent_tree *et,
267 struct extent_node **prev_ex,
268 struct extent_node **next_ex,
269 struct rb_node ***insert_p,
270 struct rb_node **insert_parent)
272 struct rb_node **pnode = &et->root.rb_node;
273 struct rb_node *parent = NULL, *tmp_node;
274 struct extent_node *en = et->cached_en;
277 *insert_parent = NULL;
281 if (RB_EMPTY_ROOT(&et->root))
285 struct extent_info *cei = &en->ei;
287 if (cei->fofs <= fofs && cei->fofs + cei->len > fofs)
288 goto lookup_neighbors;
293 en = rb_entry(*pnode, struct extent_node, rb_node);
295 if (fofs < en->ei.fofs)
296 pnode = &(*pnode)->rb_left;
297 else if (fofs >= en->ei.fofs + en->ei.len)
298 pnode = &(*pnode)->rb_right;
300 goto lookup_neighbors;
304 *insert_parent = parent;
306 en = rb_entry(parent, struct extent_node, rb_node);
308 if (parent && fofs > en->ei.fofs)
309 tmp_node = rb_next(parent);
310 *next_ex = tmp_node ?
311 rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
314 if (parent && fofs < en->ei.fofs)
315 tmp_node = rb_prev(parent);
316 *prev_ex = tmp_node ?
317 rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
321 if (fofs == en->ei.fofs) {
322 /* lookup prev node for merging backward later */
323 tmp_node = rb_prev(&en->rb_node);
324 *prev_ex = tmp_node ?
325 rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
327 if (fofs == en->ei.fofs + en->ei.len - 1) {
328 /* lookup next node for merging frontward later */
329 tmp_node = rb_next(&en->rb_node);
330 *next_ex = tmp_node ?
331 rb_entry(tmp_node, struct extent_node, rb_node) : NULL;
336 static struct extent_node *__try_merge_extent_node(struct f2fs_sb_info *sbi,
337 struct extent_tree *et, struct extent_info *ei,
338 struct extent_node **den,
339 struct extent_node *prev_ex,
340 struct extent_node *next_ex)
342 struct extent_node *en = NULL;
344 if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
345 prev_ex->ei.len += ei->len;
350 if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
352 __detach_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;
362 __try_update_largest_extent(et, en);
368 static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
369 struct extent_tree *et, struct extent_info *ei,
370 struct rb_node **insert_p,
371 struct rb_node *insert_parent)
373 struct rb_node **p = &et->root.rb_node;
374 struct rb_node *parent = NULL;
375 struct extent_node *en = NULL;
377 if (insert_p && insert_parent) {
378 parent = insert_parent;
385 en = rb_entry(parent, struct extent_node, rb_node);
387 if (ei->fofs < en->ei.fofs)
389 else if (ei->fofs >= en->ei.fofs + en->ei.len)
395 en = __attach_extent_node(sbi, et, ei, parent, p);
399 __try_update_largest_extent(et, en);
404 static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
405 pgoff_t fofs, block_t blkaddr, unsigned int len)
407 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
408 struct extent_tree *et = F2FS_I(inode)->extent_tree;
409 struct extent_node *en = NULL, *en1 = NULL;
410 struct extent_node *prev_en = NULL, *next_en = NULL;
411 struct extent_info ei, dei, prev;
412 struct rb_node **insert_p = NULL, *insert_parent = NULL;
413 unsigned int end = fofs + len;
414 unsigned int pos = (unsigned int)fofs;
419 trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
421 write_lock(&et->lock);
423 if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT)) {
424 write_unlock(&et->lock);
432 * drop largest extent before lookup, in case it's already
433 * been shrunk from extent tree
435 __drop_largest_extent(inode, fofs, len);
437 /* 1. lookup first extent node in range [fofs, fofs + len - 1] */
438 en = __lookup_extent_tree_ret(et, fofs, &prev_en, &next_en,
439 &insert_p, &insert_parent);
443 /* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
444 while (en && en->ei.fofs < end) {
445 unsigned int org_end;
446 int parts = 0; /* # of parts current extent split into */
448 next_en = en1 = NULL;
451 org_end = dei.fofs + dei.len;
452 f2fs_bug_on(sbi, pos >= org_end);
454 if (pos > dei.fofs && pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
455 en->ei.len = pos - en->ei.fofs;
460 if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
462 set_extent_info(&ei, end,
463 end - dei.fofs + dei.blk,
465 en1 = __insert_extent_tree(sbi, et, &ei,
470 en->ei.blk += end - dei.fofs;
471 en->ei.len -= end - dei.fofs;
478 struct rb_node *node = rb_next(&en->rb_node);
481 rb_entry(node, struct extent_node, rb_node)
486 __try_update_largest_extent(et, en);
488 __detach_extent_node(sbi, et, en);
491 * if original extent is split into zero or two parts, extent
492 * tree has been altered by deletion or insertion, therefore
493 * invalidate pointers regard to tree.
497 insert_parent = NULL;
500 /* update in global extent list */
501 spin_lock(&sbi->extent_lock);
502 if (!parts && !list_empty(&en->list))
505 list_add_tail(&en1->list, &sbi->extent_list);
506 spin_unlock(&sbi->extent_lock);
508 /* release extent node */
510 kmem_cache_free(extent_node_slab, en);
515 /* 3. update extent in extent cache */
517 struct extent_node *den = NULL;
519 set_extent_info(&ei, fofs, blkaddr, len);
520 en1 = __try_merge_extent_node(sbi, et, &ei, &den,
523 en1 = __insert_extent_tree(sbi, et, &ei,
524 insert_p, insert_parent);
526 /* give up extent_cache, if split and small updates happen */
528 prev.len < F2FS_MIN_EXTENT_LEN &&
529 et->largest.len < F2FS_MIN_EXTENT_LEN) {
531 set_inode_flag(F2FS_I(inode), FI_NO_EXTENT);
534 spin_lock(&sbi->extent_lock);
536 if (list_empty(&en1->list))
537 list_add_tail(&en1->list, &sbi->extent_list);
539 list_move_tail(&en1->list, &sbi->extent_list);
541 if (den && !list_empty(&den->list))
542 list_del(&den->list);
543 spin_unlock(&sbi->extent_lock);
546 kmem_cache_free(extent_node_slab, den);
549 if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))
550 __free_extent_tree(sbi, et, true);
552 write_unlock(&et->lock);
554 return !__is_extent_same(&prev, &et->largest);
557 unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
559 struct extent_tree *treevec[EXT_TREE_VEC_SIZE];
560 struct extent_node *en, *tmp;
561 unsigned long ino = F2FS_ROOT_INO(sbi);
562 struct radix_tree_root *root = &sbi->extent_tree_root;
564 unsigned int node_cnt = 0, tree_cnt = 0;
567 if (!test_opt(sbi, EXTENT_CACHE))
570 if (!down_write_trylock(&sbi->extent_tree_lock))
573 /* 1. remove unreferenced extent tree */
574 while ((found = radix_tree_gang_lookup(root,
575 (void **)treevec, ino, EXT_TREE_VEC_SIZE))) {
578 ino = treevec[found - 1]->ino + 1;
579 for (i = 0; i < found; i++) {
580 struct extent_tree *et = treevec[i];
582 if (!atomic_read(&et->refcount)) {
583 write_lock(&et->lock);
584 node_cnt += __free_extent_tree(sbi, et, true);
585 write_unlock(&et->lock);
587 radix_tree_delete(root, et->ino);
588 kmem_cache_free(extent_tree_slab, et);
589 sbi->total_ext_tree--;
592 if (node_cnt + tree_cnt >= nr_shrink)
597 up_write(&sbi->extent_tree_lock);
599 /* 2. remove LRU extent entries */
600 if (!down_write_trylock(&sbi->extent_tree_lock))
603 remained = nr_shrink - (node_cnt + tree_cnt);
605 spin_lock(&sbi->extent_lock);
606 list_for_each_entry_safe(en, tmp, &sbi->extent_list, list) {
609 list_del_init(&en->list);
611 spin_unlock(&sbi->extent_lock);
614 * reset ino for searching victims from beginning of global extent tree.
616 ino = F2FS_ROOT_INO(sbi);
618 while ((found = radix_tree_gang_lookup(root,
619 (void **)treevec, ino, EXT_TREE_VEC_SIZE))) {
622 ino = treevec[found - 1]->ino + 1;
623 for (i = 0; i < found; i++) {
624 struct extent_tree *et = treevec[i];
626 write_lock(&et->lock);
627 node_cnt += __free_extent_tree(sbi, et, false);
628 write_unlock(&et->lock);
630 if (node_cnt + tree_cnt >= nr_shrink)
635 up_write(&sbi->extent_tree_lock);
637 trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt);
639 return node_cnt + tree_cnt;
642 unsigned int f2fs_destroy_extent_node(struct inode *inode)
644 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
645 struct extent_tree *et = F2FS_I(inode)->extent_tree;
646 unsigned int node_cnt = 0;
651 write_lock(&et->lock);
652 node_cnt = __free_extent_tree(sbi, et, true);
653 write_unlock(&et->lock);
658 void f2fs_destroy_extent_tree(struct inode *inode)
660 struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
661 struct extent_tree *et = F2FS_I(inode)->extent_tree;
662 unsigned int node_cnt = 0;
667 if (inode->i_nlink && !is_bad_inode(inode) && et->count) {
668 atomic_dec(&et->refcount);
672 /* free all extent info belong to this extent tree */
673 node_cnt = f2fs_destroy_extent_node(inode);
675 /* delete extent tree entry in radix tree */
676 down_write(&sbi->extent_tree_lock);
677 atomic_dec(&et->refcount);
678 f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
679 radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
680 kmem_cache_free(extent_tree_slab, et);
681 sbi->total_ext_tree--;
682 up_write(&sbi->extent_tree_lock);
684 F2FS_I(inode)->extent_tree = NULL;
686 trace_f2fs_destroy_extent_tree(inode, node_cnt);
689 bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
690 struct extent_info *ei)
692 if (!f2fs_may_extent_tree(inode))
695 return f2fs_lookup_extent_tree(inode, pgofs, ei);
698 void f2fs_update_extent_cache(struct dnode_of_data *dn)
700 struct f2fs_inode_info *fi = F2FS_I(dn->inode);
703 if (!f2fs_may_extent_tree(dn->inode))
706 f2fs_bug_on(F2FS_I_SB(dn->inode), dn->data_blkaddr == NEW_ADDR);
709 fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) +
712 if (f2fs_update_extent_tree_range(dn->inode, fofs, dn->data_blkaddr, 1))
716 void f2fs_update_extent_cache_range(struct dnode_of_data *dn,
717 pgoff_t fofs, block_t blkaddr, unsigned int len)
720 if (!f2fs_may_extent_tree(dn->inode))
723 if (f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len))
727 void init_extent_cache_info(struct f2fs_sb_info *sbi)
729 INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
730 init_rwsem(&sbi->extent_tree_lock);
731 INIT_LIST_HEAD(&sbi->extent_list);
732 spin_lock_init(&sbi->extent_lock);
733 sbi->total_ext_tree = 0;
734 atomic_set(&sbi->total_ext_node, 0);
737 int __init create_extent_cache(void)
739 extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
740 sizeof(struct extent_tree));
741 if (!extent_tree_slab)
743 extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
744 sizeof(struct extent_node));
745 if (!extent_node_slab) {
746 kmem_cache_destroy(extent_tree_slab);
752 void destroy_extent_cache(void)
754 kmem_cache_destroy(extent_node_slab);
755 kmem_cache_destroy(extent_tree_slab);