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Merge branch 'akpm-current/current'
[karo-tx-linux.git] / fs / f2fs / node.c
1 /*
2  * fs/f2fs/node.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/fs.h>
12 #include <linux/f2fs_fs.h>
13 #include <linux/mpage.h>
14 #include <linux/backing-dev.h>
15 #include <linux/blkdev.h>
16 #include <linux/pagevec.h>
17 #include <linux/swap.h>
18
19 #include "f2fs.h"
20 #include "node.h"
21 #include "segment.h"
22 #include <trace/events/f2fs.h>
23
24 #define on_build_free_nids(nmi) mutex_is_locked(&nm_i->build_lock)
25
26 static struct kmem_cache *nat_entry_slab;
27 static struct kmem_cache *free_nid_slab;
28
29 bool available_free_memory(struct f2fs_sb_info *sbi, int type)
30 {
31         struct f2fs_nm_info *nm_i = NM_I(sbi);
32         struct sysinfo val;
33         unsigned long mem_size = 0;
34         bool res = false;
35
36         si_meminfo(&val);
37         /* give 25%, 25%, 50% memory for each components respectively */
38         if (type == FREE_NIDS) {
39                 mem_size = (nm_i->fcnt * sizeof(struct free_nid)) >> 12;
40                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
41         } else if (type == NAT_ENTRIES) {
42                 mem_size = (nm_i->nat_cnt * sizeof(struct nat_entry)) >> 12;
43                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
44         } else if (type == DIRTY_DENTS) {
45                 mem_size = get_pages(sbi, F2FS_DIRTY_DENTS);
46                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 1);
47         }
48         return res;
49 }
50
51 static void clear_node_page_dirty(struct page *page)
52 {
53         struct address_space *mapping = page->mapping;
54         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
55         unsigned int long flags;
56
57         if (PageDirty(page)) {
58                 spin_lock_irqsave(&mapping->tree_lock, flags);
59                 radix_tree_tag_clear(&mapping->page_tree,
60                                 page_index(page),
61                                 PAGECACHE_TAG_DIRTY);
62                 spin_unlock_irqrestore(&mapping->tree_lock, flags);
63
64                 clear_page_dirty_for_io(page);
65                 dec_page_count(sbi, F2FS_DIRTY_NODES);
66         }
67         ClearPageUptodate(page);
68 }
69
70 static struct page *get_current_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
71 {
72         pgoff_t index = current_nat_addr(sbi, nid);
73         return get_meta_page(sbi, index);
74 }
75
76 static struct page *get_next_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
77 {
78         struct page *src_page;
79         struct page *dst_page;
80         pgoff_t src_off;
81         pgoff_t dst_off;
82         void *src_addr;
83         void *dst_addr;
84         struct f2fs_nm_info *nm_i = NM_I(sbi);
85
86         src_off = current_nat_addr(sbi, nid);
87         dst_off = next_nat_addr(sbi, src_off);
88
89         /* get current nat block page with lock */
90         src_page = get_meta_page(sbi, src_off);
91
92         /* Dirty src_page means that it is already the new target NAT page. */
93         if (PageDirty(src_page))
94                 return src_page;
95
96         dst_page = grab_meta_page(sbi, dst_off);
97
98         src_addr = page_address(src_page);
99         dst_addr = page_address(dst_page);
100         memcpy(dst_addr, src_addr, PAGE_CACHE_SIZE);
101         set_page_dirty(dst_page);
102         f2fs_put_page(src_page, 1);
103
104         set_to_next_nat(nm_i, nid);
105
106         return dst_page;
107 }
108
109 static struct nat_entry *__lookup_nat_cache(struct f2fs_nm_info *nm_i, nid_t n)
110 {
111         return radix_tree_lookup(&nm_i->nat_root, n);
112 }
113
114 static unsigned int __gang_lookup_nat_cache(struct f2fs_nm_info *nm_i,
115                 nid_t start, unsigned int nr, struct nat_entry **ep)
116 {
117         return radix_tree_gang_lookup(&nm_i->nat_root, (void **)ep, start, nr);
118 }
119
120 static void __del_from_nat_cache(struct f2fs_nm_info *nm_i, struct nat_entry *e)
121 {
122         list_del(&e->list);
123         radix_tree_delete(&nm_i->nat_root, nat_get_nid(e));
124         nm_i->nat_cnt--;
125         kmem_cache_free(nat_entry_slab, e);
126 }
127
128 int is_checkpointed_node(struct f2fs_sb_info *sbi, nid_t nid)
129 {
130         struct f2fs_nm_info *nm_i = NM_I(sbi);
131         struct nat_entry *e;
132         int is_cp = 1;
133
134         read_lock(&nm_i->nat_tree_lock);
135         e = __lookup_nat_cache(nm_i, nid);
136         if (e && !e->checkpointed)
137                 is_cp = 0;
138         read_unlock(&nm_i->nat_tree_lock);
139         return is_cp;
140 }
141
142 bool fsync_mark_done(struct f2fs_sb_info *sbi, nid_t nid)
143 {
144         struct f2fs_nm_info *nm_i = NM_I(sbi);
145         struct nat_entry *e;
146         bool fsync_done = false;
147
148         read_lock(&nm_i->nat_tree_lock);
149         e = __lookup_nat_cache(nm_i, nid);
150         if (e)
151                 fsync_done = e->fsync_done;
152         read_unlock(&nm_i->nat_tree_lock);
153         return fsync_done;
154 }
155
156 static struct nat_entry *grab_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid)
157 {
158         struct nat_entry *new;
159
160         new = kmem_cache_alloc(nat_entry_slab, GFP_ATOMIC);
161         if (!new)
162                 return NULL;
163         if (radix_tree_insert(&nm_i->nat_root, nid, new)) {
164                 kmem_cache_free(nat_entry_slab, new);
165                 return NULL;
166         }
167         memset(new, 0, sizeof(struct nat_entry));
168         nat_set_nid(new, nid);
169         new->checkpointed = true;
170         list_add_tail(&new->list, &nm_i->nat_entries);
171         nm_i->nat_cnt++;
172         return new;
173 }
174
175 static void cache_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid,
176                                                 struct f2fs_nat_entry *ne)
177 {
178         struct nat_entry *e;
179 retry:
180         write_lock(&nm_i->nat_tree_lock);
181         e = __lookup_nat_cache(nm_i, nid);
182         if (!e) {
183                 e = grab_nat_entry(nm_i, nid);
184                 if (!e) {
185                         write_unlock(&nm_i->nat_tree_lock);
186                         goto retry;
187                 }
188                 node_info_from_raw_nat(&e->ni, ne);
189         }
190         write_unlock(&nm_i->nat_tree_lock);
191 }
192
193 static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni,
194                         block_t new_blkaddr, bool fsync_done)
195 {
196         struct f2fs_nm_info *nm_i = NM_I(sbi);
197         struct nat_entry *e;
198 retry:
199         write_lock(&nm_i->nat_tree_lock);
200         e = __lookup_nat_cache(nm_i, ni->nid);
201         if (!e) {
202                 e = grab_nat_entry(nm_i, ni->nid);
203                 if (!e) {
204                         write_unlock(&nm_i->nat_tree_lock);
205                         goto retry;
206                 }
207                 e->ni = *ni;
208                 f2fs_bug_on(ni->blk_addr == NEW_ADDR);
209         } else if (new_blkaddr == NEW_ADDR) {
210                 /*
211                  * when nid is reallocated,
212                  * previous nat entry can be remained in nat cache.
213                  * So, reinitialize it with new information.
214                  */
215                 e->ni = *ni;
216                 f2fs_bug_on(ni->blk_addr != NULL_ADDR);
217         }
218
219         /* sanity check */
220         f2fs_bug_on(nat_get_blkaddr(e) != ni->blk_addr);
221         f2fs_bug_on(nat_get_blkaddr(e) == NULL_ADDR &&
222                         new_blkaddr == NULL_ADDR);
223         f2fs_bug_on(nat_get_blkaddr(e) == NEW_ADDR &&
224                         new_blkaddr == NEW_ADDR);
225         f2fs_bug_on(nat_get_blkaddr(e) != NEW_ADDR &&
226                         nat_get_blkaddr(e) != NULL_ADDR &&
227                         new_blkaddr == NEW_ADDR);
228
229         /* increament version no as node is removed */
230         if (nat_get_blkaddr(e) != NEW_ADDR && new_blkaddr == NULL_ADDR) {
231                 unsigned char version = nat_get_version(e);
232                 nat_set_version(e, inc_node_version(version));
233         }
234
235         /* change address */
236         nat_set_blkaddr(e, new_blkaddr);
237         __set_nat_cache_dirty(nm_i, e);
238
239         /* update fsync_mark if its inode nat entry is still alive */
240         e = __lookup_nat_cache(nm_i, ni->ino);
241         if (e)
242                 e->fsync_done = fsync_done;
243         write_unlock(&nm_i->nat_tree_lock);
244 }
245
246 int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink)
247 {
248         struct f2fs_nm_info *nm_i = NM_I(sbi);
249
250         if (available_free_memory(sbi, NAT_ENTRIES))
251                 return 0;
252
253         write_lock(&nm_i->nat_tree_lock);
254         while (nr_shrink && !list_empty(&nm_i->nat_entries)) {
255                 struct nat_entry *ne;
256                 ne = list_first_entry(&nm_i->nat_entries,
257                                         struct nat_entry, list);
258                 __del_from_nat_cache(nm_i, ne);
259                 nr_shrink--;
260         }
261         write_unlock(&nm_i->nat_tree_lock);
262         return nr_shrink;
263 }
264
265 /*
266  * This function returns always success
267  */
268 void get_node_info(struct f2fs_sb_info *sbi, nid_t nid, struct node_info *ni)
269 {
270         struct f2fs_nm_info *nm_i = NM_I(sbi);
271         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
272         struct f2fs_summary_block *sum = curseg->sum_blk;
273         nid_t start_nid = START_NID(nid);
274         struct f2fs_nat_block *nat_blk;
275         struct page *page = NULL;
276         struct f2fs_nat_entry ne;
277         struct nat_entry *e;
278         int i;
279
280         memset(&ne, 0, sizeof(struct f2fs_nat_entry));
281         ni->nid = nid;
282
283         /* Check nat cache */
284         read_lock(&nm_i->nat_tree_lock);
285         e = __lookup_nat_cache(nm_i, nid);
286         if (e) {
287                 ni->ino = nat_get_ino(e);
288                 ni->blk_addr = nat_get_blkaddr(e);
289                 ni->version = nat_get_version(e);
290         }
291         read_unlock(&nm_i->nat_tree_lock);
292         if (e)
293                 return;
294
295         /* Check current segment summary */
296         mutex_lock(&curseg->curseg_mutex);
297         i = lookup_journal_in_cursum(sum, NAT_JOURNAL, nid, 0);
298         if (i >= 0) {
299                 ne = nat_in_journal(sum, i);
300                 node_info_from_raw_nat(ni, &ne);
301         }
302         mutex_unlock(&curseg->curseg_mutex);
303         if (i >= 0)
304                 goto cache;
305
306         /* Fill node_info from nat page */
307         page = get_current_nat_page(sbi, start_nid);
308         nat_blk = (struct f2fs_nat_block *)page_address(page);
309         ne = nat_blk->entries[nid - start_nid];
310         node_info_from_raw_nat(ni, &ne);
311         f2fs_put_page(page, 1);
312 cache:
313         /* cache nat entry */
314         cache_nat_entry(NM_I(sbi), nid, &ne);
315 }
316
317 /*
318  * The maximum depth is four.
319  * Offset[0] will have raw inode offset.
320  */
321 static int get_node_path(struct f2fs_inode_info *fi, long block,
322                                 int offset[4], unsigned int noffset[4])
323 {
324         const long direct_index = ADDRS_PER_INODE(fi);
325         const long direct_blks = ADDRS_PER_BLOCK;
326         const long dptrs_per_blk = NIDS_PER_BLOCK;
327         const long indirect_blks = ADDRS_PER_BLOCK * NIDS_PER_BLOCK;
328         const long dindirect_blks = indirect_blks * NIDS_PER_BLOCK;
329         int n = 0;
330         int level = 0;
331
332         noffset[0] = 0;
333
334         if (block < direct_index) {
335                 offset[n] = block;
336                 goto got;
337         }
338         block -= direct_index;
339         if (block < direct_blks) {
340                 offset[n++] = NODE_DIR1_BLOCK;
341                 noffset[n] = 1;
342                 offset[n] = block;
343                 level = 1;
344                 goto got;
345         }
346         block -= direct_blks;
347         if (block < direct_blks) {
348                 offset[n++] = NODE_DIR2_BLOCK;
349                 noffset[n] = 2;
350                 offset[n] = block;
351                 level = 1;
352                 goto got;
353         }
354         block -= direct_blks;
355         if (block < indirect_blks) {
356                 offset[n++] = NODE_IND1_BLOCK;
357                 noffset[n] = 3;
358                 offset[n++] = block / direct_blks;
359                 noffset[n] = 4 + offset[n - 1];
360                 offset[n] = block % direct_blks;
361                 level = 2;
362                 goto got;
363         }
364         block -= indirect_blks;
365         if (block < indirect_blks) {
366                 offset[n++] = NODE_IND2_BLOCK;
367                 noffset[n] = 4 + dptrs_per_blk;
368                 offset[n++] = block / direct_blks;
369                 noffset[n] = 5 + dptrs_per_blk + offset[n - 1];
370                 offset[n] = block % direct_blks;
371                 level = 2;
372                 goto got;
373         }
374         block -= indirect_blks;
375         if (block < dindirect_blks) {
376                 offset[n++] = NODE_DIND_BLOCK;
377                 noffset[n] = 5 + (dptrs_per_blk * 2);
378                 offset[n++] = block / indirect_blks;
379                 noffset[n] = 6 + (dptrs_per_blk * 2) +
380                               offset[n - 1] * (dptrs_per_blk + 1);
381                 offset[n++] = (block / direct_blks) % dptrs_per_blk;
382                 noffset[n] = 7 + (dptrs_per_blk * 2) +
383                               offset[n - 2] * (dptrs_per_blk + 1) +
384                               offset[n - 1];
385                 offset[n] = block % direct_blks;
386                 level = 3;
387                 goto got;
388         } else {
389                 BUG();
390         }
391 got:
392         return level;
393 }
394
395 /*
396  * Caller should call f2fs_put_dnode(dn).
397  * Also, it should grab and release a rwsem by calling f2fs_lock_op() and
398  * f2fs_unlock_op() only if ro is not set RDONLY_NODE.
399  * In the case of RDONLY_NODE, we don't need to care about mutex.
400  */
401 int get_dnode_of_data(struct dnode_of_data *dn, pgoff_t index, int mode)
402 {
403         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
404         struct page *npage[4];
405         struct page *parent;
406         int offset[4];
407         unsigned int noffset[4];
408         nid_t nids[4];
409         int level, i;
410         int err = 0;
411
412         level = get_node_path(F2FS_I(dn->inode), index, offset, noffset);
413
414         nids[0] = dn->inode->i_ino;
415         npage[0] = dn->inode_page;
416
417         if (!npage[0]) {
418                 npage[0] = get_node_page(sbi, nids[0]);
419                 if (IS_ERR(npage[0]))
420                         return PTR_ERR(npage[0]);
421         }
422         parent = npage[0];
423         if (level != 0)
424                 nids[1] = get_nid(parent, offset[0], true);
425         dn->inode_page = npage[0];
426         dn->inode_page_locked = true;
427
428         /* get indirect or direct nodes */
429         for (i = 1; i <= level; i++) {
430                 bool done = false;
431
432                 if (!nids[i] && mode == ALLOC_NODE) {
433                         /* alloc new node */
434                         if (!alloc_nid(sbi, &(nids[i]))) {
435                                 err = -ENOSPC;
436                                 goto release_pages;
437                         }
438
439                         dn->nid = nids[i];
440                         npage[i] = new_node_page(dn, noffset[i], NULL);
441                         if (IS_ERR(npage[i])) {
442                                 alloc_nid_failed(sbi, nids[i]);
443                                 err = PTR_ERR(npage[i]);
444                                 goto release_pages;
445                         }
446
447                         set_nid(parent, offset[i - 1], nids[i], i == 1);
448                         alloc_nid_done(sbi, nids[i]);
449                         done = true;
450                 } else if (mode == LOOKUP_NODE_RA && i == level && level > 1) {
451                         npage[i] = get_node_page_ra(parent, offset[i - 1]);
452                         if (IS_ERR(npage[i])) {
453                                 err = PTR_ERR(npage[i]);
454                                 goto release_pages;
455                         }
456                         done = true;
457                 }
458                 if (i == 1) {
459                         dn->inode_page_locked = false;
460                         unlock_page(parent);
461                 } else {
462                         f2fs_put_page(parent, 1);
463                 }
464
465                 if (!done) {
466                         npage[i] = get_node_page(sbi, nids[i]);
467                         if (IS_ERR(npage[i])) {
468                                 err = PTR_ERR(npage[i]);
469                                 f2fs_put_page(npage[0], 0);
470                                 goto release_out;
471                         }
472                 }
473                 if (i < level) {
474                         parent = npage[i];
475                         nids[i + 1] = get_nid(parent, offset[i], false);
476                 }
477         }
478         dn->nid = nids[level];
479         dn->ofs_in_node = offset[level];
480         dn->node_page = npage[level];
481         dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
482         return 0;
483
484 release_pages:
485         f2fs_put_page(parent, 1);
486         if (i > 1)
487                 f2fs_put_page(npage[0], 0);
488 release_out:
489         dn->inode_page = NULL;
490         dn->node_page = NULL;
491         return err;
492 }
493
494 static void truncate_node(struct dnode_of_data *dn)
495 {
496         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
497         struct node_info ni;
498
499         get_node_info(sbi, dn->nid, &ni);
500         if (dn->inode->i_blocks == 0) {
501                 f2fs_bug_on(ni.blk_addr != NULL_ADDR);
502                 goto invalidate;
503         }
504         f2fs_bug_on(ni.blk_addr == NULL_ADDR);
505
506         /* Deallocate node address */
507         invalidate_blocks(sbi, ni.blk_addr);
508         dec_valid_node_count(sbi, dn->inode);
509         set_node_addr(sbi, &ni, NULL_ADDR, false);
510
511         if (dn->nid == dn->inode->i_ino) {
512                 remove_orphan_inode(sbi, dn->nid);
513                 dec_valid_inode_count(sbi);
514         } else {
515                 sync_inode_page(dn);
516         }
517 invalidate:
518         clear_node_page_dirty(dn->node_page);
519         F2FS_SET_SB_DIRT(sbi);
520
521         f2fs_put_page(dn->node_page, 1);
522
523         invalidate_mapping_pages(NODE_MAPPING(sbi),
524                         dn->node_page->index, dn->node_page->index);
525
526         dn->node_page = NULL;
527         trace_f2fs_truncate_node(dn->inode, dn->nid, ni.blk_addr);
528 }
529
530 static int truncate_dnode(struct dnode_of_data *dn)
531 {
532         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
533         struct page *page;
534
535         if (dn->nid == 0)
536                 return 1;
537
538         /* get direct node */
539         page = get_node_page(sbi, dn->nid);
540         if (IS_ERR(page) && PTR_ERR(page) == -ENOENT)
541                 return 1;
542         else if (IS_ERR(page))
543                 return PTR_ERR(page);
544
545         /* Make dnode_of_data for parameter */
546         dn->node_page = page;
547         dn->ofs_in_node = 0;
548         truncate_data_blocks(dn);
549         truncate_node(dn);
550         return 1;
551 }
552
553 static int truncate_nodes(struct dnode_of_data *dn, unsigned int nofs,
554                                                 int ofs, int depth)
555 {
556         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
557         struct dnode_of_data rdn = *dn;
558         struct page *page;
559         struct f2fs_node *rn;
560         nid_t child_nid;
561         unsigned int child_nofs;
562         int freed = 0;
563         int i, ret;
564
565         if (dn->nid == 0)
566                 return NIDS_PER_BLOCK + 1;
567
568         trace_f2fs_truncate_nodes_enter(dn->inode, dn->nid, dn->data_blkaddr);
569
570         page = get_node_page(sbi, dn->nid);
571         if (IS_ERR(page)) {
572                 trace_f2fs_truncate_nodes_exit(dn->inode, PTR_ERR(page));
573                 return PTR_ERR(page);
574         }
575
576         rn = F2FS_NODE(page);
577         if (depth < 3) {
578                 for (i = ofs; i < NIDS_PER_BLOCK; i++, freed++) {
579                         child_nid = le32_to_cpu(rn->in.nid[i]);
580                         if (child_nid == 0)
581                                 continue;
582                         rdn.nid = child_nid;
583                         ret = truncate_dnode(&rdn);
584                         if (ret < 0)
585                                 goto out_err;
586                         set_nid(page, i, 0, false);
587                 }
588         } else {
589                 child_nofs = nofs + ofs * (NIDS_PER_BLOCK + 1) + 1;
590                 for (i = ofs; i < NIDS_PER_BLOCK; i++) {
591                         child_nid = le32_to_cpu(rn->in.nid[i]);
592                         if (child_nid == 0) {
593                                 child_nofs += NIDS_PER_BLOCK + 1;
594                                 continue;
595                         }
596                         rdn.nid = child_nid;
597                         ret = truncate_nodes(&rdn, child_nofs, 0, depth - 1);
598                         if (ret == (NIDS_PER_BLOCK + 1)) {
599                                 set_nid(page, i, 0, false);
600                                 child_nofs += ret;
601                         } else if (ret < 0 && ret != -ENOENT) {
602                                 goto out_err;
603                         }
604                 }
605                 freed = child_nofs;
606         }
607
608         if (!ofs) {
609                 /* remove current indirect node */
610                 dn->node_page = page;
611                 truncate_node(dn);
612                 freed++;
613         } else {
614                 f2fs_put_page(page, 1);
615         }
616         trace_f2fs_truncate_nodes_exit(dn->inode, freed);
617         return freed;
618
619 out_err:
620         f2fs_put_page(page, 1);
621         trace_f2fs_truncate_nodes_exit(dn->inode, ret);
622         return ret;
623 }
624
625 static int truncate_partial_nodes(struct dnode_of_data *dn,
626                         struct f2fs_inode *ri, int *offset, int depth)
627 {
628         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
629         struct page *pages[2];
630         nid_t nid[3];
631         nid_t child_nid;
632         int err = 0;
633         int i;
634         int idx = depth - 2;
635
636         nid[0] = le32_to_cpu(ri->i_nid[offset[0] - NODE_DIR1_BLOCK]);
637         if (!nid[0])
638                 return 0;
639
640         /* get indirect nodes in the path */
641         for (i = 0; i < idx + 1; i++) {
642                 /* refernece count'll be increased */
643                 pages[i] = get_node_page(sbi, nid[i]);
644                 if (IS_ERR(pages[i])) {
645                         err = PTR_ERR(pages[i]);
646                         idx = i - 1;
647                         goto fail;
648                 }
649                 nid[i + 1] = get_nid(pages[i], offset[i + 1], false);
650         }
651
652         /* free direct nodes linked to a partial indirect node */
653         for (i = offset[idx + 1]; i < NIDS_PER_BLOCK; i++) {
654                 child_nid = get_nid(pages[idx], i, false);
655                 if (!child_nid)
656                         continue;
657                 dn->nid = child_nid;
658                 err = truncate_dnode(dn);
659                 if (err < 0)
660                         goto fail;
661                 set_nid(pages[idx], i, 0, false);
662         }
663
664         if (offset[idx + 1] == 0) {
665                 dn->node_page = pages[idx];
666                 dn->nid = nid[idx];
667                 truncate_node(dn);
668         } else {
669                 f2fs_put_page(pages[idx], 1);
670         }
671         offset[idx]++;
672         offset[idx + 1] = 0;
673         idx--;
674 fail:
675         for (i = idx; i >= 0; i--)
676                 f2fs_put_page(pages[i], 1);
677
678         trace_f2fs_truncate_partial_nodes(dn->inode, nid, depth, err);
679
680         return err;
681 }
682
683 /*
684  * All the block addresses of data and nodes should be nullified.
685  */
686 int truncate_inode_blocks(struct inode *inode, pgoff_t from)
687 {
688         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
689         int err = 0, cont = 1;
690         int level, offset[4], noffset[4];
691         unsigned int nofs = 0;
692         struct f2fs_inode *ri;
693         struct dnode_of_data dn;
694         struct page *page;
695
696         trace_f2fs_truncate_inode_blocks_enter(inode, from);
697
698         level = get_node_path(F2FS_I(inode), from, offset, noffset);
699 restart:
700         page = get_node_page(sbi, inode->i_ino);
701         if (IS_ERR(page)) {
702                 trace_f2fs_truncate_inode_blocks_exit(inode, PTR_ERR(page));
703                 return PTR_ERR(page);
704         }
705
706         set_new_dnode(&dn, inode, page, NULL, 0);
707         unlock_page(page);
708
709         ri = F2FS_INODE(page);
710         switch (level) {
711         case 0:
712         case 1:
713                 nofs = noffset[1];
714                 break;
715         case 2:
716                 nofs = noffset[1];
717                 if (!offset[level - 1])
718                         goto skip_partial;
719                 err = truncate_partial_nodes(&dn, ri, offset, level);
720                 if (err < 0 && err != -ENOENT)
721                         goto fail;
722                 nofs += 1 + NIDS_PER_BLOCK;
723                 break;
724         case 3:
725                 nofs = 5 + 2 * NIDS_PER_BLOCK;
726                 if (!offset[level - 1])
727                         goto skip_partial;
728                 err = truncate_partial_nodes(&dn, ri, offset, level);
729                 if (err < 0 && err != -ENOENT)
730                         goto fail;
731                 break;
732         default:
733                 BUG();
734         }
735
736 skip_partial:
737         while (cont) {
738                 dn.nid = le32_to_cpu(ri->i_nid[offset[0] - NODE_DIR1_BLOCK]);
739                 switch (offset[0]) {
740                 case NODE_DIR1_BLOCK:
741                 case NODE_DIR2_BLOCK:
742                         err = truncate_dnode(&dn);
743                         break;
744
745                 case NODE_IND1_BLOCK:
746                 case NODE_IND2_BLOCK:
747                         err = truncate_nodes(&dn, nofs, offset[1], 2);
748                         break;
749
750                 case NODE_DIND_BLOCK:
751                         err = truncate_nodes(&dn, nofs, offset[1], 3);
752                         cont = 0;
753                         break;
754
755                 default:
756                         BUG();
757                 }
758                 if (err < 0 && err != -ENOENT)
759                         goto fail;
760                 if (offset[1] == 0 &&
761                                 ri->i_nid[offset[0] - NODE_DIR1_BLOCK]) {
762                         lock_page(page);
763                         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
764                                 f2fs_put_page(page, 1);
765                                 goto restart;
766                         }
767                         f2fs_wait_on_page_writeback(page, NODE);
768                         ri->i_nid[offset[0] - NODE_DIR1_BLOCK] = 0;
769                         set_page_dirty(page);
770                         unlock_page(page);
771                 }
772                 offset[1] = 0;
773                 offset[0]++;
774                 nofs += err;
775         }
776 fail:
777         f2fs_put_page(page, 0);
778         trace_f2fs_truncate_inode_blocks_exit(inode, err);
779         return err > 0 ? 0 : err;
780 }
781
782 int truncate_xattr_node(struct inode *inode, struct page *page)
783 {
784         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
785         nid_t nid = F2FS_I(inode)->i_xattr_nid;
786         struct dnode_of_data dn;
787         struct page *npage;
788
789         if (!nid)
790                 return 0;
791
792         npage = get_node_page(sbi, nid);
793         if (IS_ERR(npage))
794                 return PTR_ERR(npage);
795
796         F2FS_I(inode)->i_xattr_nid = 0;
797
798         /* need to do checkpoint during fsync */
799         F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
800
801         set_new_dnode(&dn, inode, page, npage, nid);
802
803         if (page)
804                 dn.inode_page_locked = true;
805         truncate_node(&dn);
806         return 0;
807 }
808
809 /*
810  * Caller should grab and release a rwsem by calling f2fs_lock_op() and
811  * f2fs_unlock_op().
812  */
813 void remove_inode_page(struct inode *inode)
814 {
815         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
816         struct page *page;
817         nid_t ino = inode->i_ino;
818         struct dnode_of_data dn;
819
820         page = get_node_page(sbi, ino);
821         if (IS_ERR(page))
822                 return;
823
824         if (truncate_xattr_node(inode, page)) {
825                 f2fs_put_page(page, 1);
826                 return;
827         }
828         /* 0 is possible, after f2fs_new_inode() is failed */
829         f2fs_bug_on(inode->i_blocks != 0 && inode->i_blocks != 1);
830         set_new_dnode(&dn, inode, page, page, ino);
831         truncate_node(&dn);
832 }
833
834 struct page *new_inode_page(struct inode *inode, const struct qstr *name)
835 {
836         struct dnode_of_data dn;
837
838         /* allocate inode page for new inode */
839         set_new_dnode(&dn, inode, NULL, NULL, inode->i_ino);
840
841         /* caller should f2fs_put_page(page, 1); */
842         return new_node_page(&dn, 0, NULL);
843 }
844
845 struct page *new_node_page(struct dnode_of_data *dn,
846                                 unsigned int ofs, struct page *ipage)
847 {
848         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
849         struct node_info old_ni, new_ni;
850         struct page *page;
851         int err;
852
853         if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
854                 return ERR_PTR(-EPERM);
855
856         page = grab_cache_page(NODE_MAPPING(sbi), dn->nid);
857         if (!page)
858                 return ERR_PTR(-ENOMEM);
859
860         if (unlikely(!inc_valid_node_count(sbi, dn->inode))) {
861                 err = -ENOSPC;
862                 goto fail;
863         }
864
865         get_node_info(sbi, dn->nid, &old_ni);
866
867         /* Reinitialize old_ni with new node page */
868         f2fs_bug_on(old_ni.blk_addr != NULL_ADDR);
869         new_ni = old_ni;
870         new_ni.ino = dn->inode->i_ino;
871         set_node_addr(sbi, &new_ni, NEW_ADDR, false);
872
873         f2fs_wait_on_page_writeback(page, NODE);
874         fill_node_footer(page, dn->nid, dn->inode->i_ino, ofs, true);
875         set_cold_node(dn->inode, page);
876         SetPageUptodate(page);
877         set_page_dirty(page);
878
879         if (f2fs_has_xattr_block(ofs))
880                 F2FS_I(dn->inode)->i_xattr_nid = dn->nid;
881
882         dn->node_page = page;
883         if (ipage)
884                 update_inode(dn->inode, ipage);
885         else
886                 sync_inode_page(dn);
887         if (ofs == 0)
888                 inc_valid_inode_count(sbi);
889
890         return page;
891
892 fail:
893         clear_node_page_dirty(page);
894         f2fs_put_page(page, 1);
895         return ERR_PTR(err);
896 }
897
898 /*
899  * Caller should do after getting the following values.
900  * 0: f2fs_put_page(page, 0)
901  * LOCKED_PAGE: f2fs_put_page(page, 1)
902  * error: nothing
903  */
904 static int read_node_page(struct page *page, int rw)
905 {
906         struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
907         struct node_info ni;
908
909         get_node_info(sbi, page->index, &ni);
910
911         if (unlikely(ni.blk_addr == NULL_ADDR)) {
912                 f2fs_put_page(page, 1);
913                 return -ENOENT;
914         }
915
916         if (PageUptodate(page))
917                 return LOCKED_PAGE;
918
919         return f2fs_submit_page_bio(sbi, page, ni.blk_addr, rw);
920 }
921
922 /*
923  * Readahead a node page
924  */
925 void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid)
926 {
927         struct page *apage;
928         int err;
929
930         apage = find_get_page(NODE_MAPPING(sbi), nid);
931         if (apage && PageUptodate(apage)) {
932                 f2fs_put_page(apage, 0);
933                 return;
934         }
935         f2fs_put_page(apage, 0);
936
937         apage = grab_cache_page(NODE_MAPPING(sbi), nid);
938         if (!apage)
939                 return;
940
941         err = read_node_page(apage, READA);
942         if (err == 0)
943                 f2fs_put_page(apage, 0);
944         else if (err == LOCKED_PAGE)
945                 f2fs_put_page(apage, 1);
946 }
947
948 struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
949 {
950         struct page *page;
951         int err;
952 repeat:
953         page = grab_cache_page(NODE_MAPPING(sbi), nid);
954         if (!page)
955                 return ERR_PTR(-ENOMEM);
956
957         err = read_node_page(page, READ_SYNC);
958         if (err < 0)
959                 return ERR_PTR(err);
960         else if (err == LOCKED_PAGE)
961                 goto got_it;
962
963         lock_page(page);
964         if (unlikely(!PageUptodate(page) || nid != nid_of_node(page))) {
965                 f2fs_put_page(page, 1);
966                 return ERR_PTR(-EIO);
967         }
968         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
969                 f2fs_put_page(page, 1);
970                 goto repeat;
971         }
972 got_it:
973         return page;
974 }
975
976 /*
977  * Return a locked page for the desired node page.
978  * And, readahead MAX_RA_NODE number of node pages.
979  */
980 struct page *get_node_page_ra(struct page *parent, int start)
981 {
982         struct f2fs_sb_info *sbi = F2FS_SB(parent->mapping->host->i_sb);
983         struct blk_plug plug;
984         struct page *page;
985         int err, i, end;
986         nid_t nid;
987
988         /* First, try getting the desired direct node. */
989         nid = get_nid(parent, start, false);
990         if (!nid)
991                 return ERR_PTR(-ENOENT);
992 repeat:
993         page = grab_cache_page(NODE_MAPPING(sbi), nid);
994         if (!page)
995                 return ERR_PTR(-ENOMEM);
996
997         err = read_node_page(page, READ_SYNC);
998         if (err < 0)
999                 return ERR_PTR(err);
1000         else if (err == LOCKED_PAGE)
1001                 goto page_hit;
1002
1003         blk_start_plug(&plug);
1004
1005         /* Then, try readahead for siblings of the desired node */
1006         end = start + MAX_RA_NODE;
1007         end = min(end, NIDS_PER_BLOCK);
1008         for (i = start + 1; i < end; i++) {
1009                 nid = get_nid(parent, i, false);
1010                 if (!nid)
1011                         continue;
1012                 ra_node_page(sbi, nid);
1013         }
1014
1015         blk_finish_plug(&plug);
1016
1017         lock_page(page);
1018         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
1019                 f2fs_put_page(page, 1);
1020                 goto repeat;
1021         }
1022 page_hit:
1023         if (unlikely(!PageUptodate(page))) {
1024                 f2fs_put_page(page, 1);
1025                 return ERR_PTR(-EIO);
1026         }
1027         return page;
1028 }
1029
1030 void sync_inode_page(struct dnode_of_data *dn)
1031 {
1032         if (IS_INODE(dn->node_page) || dn->inode_page == dn->node_page) {
1033                 update_inode(dn->inode, dn->node_page);
1034         } else if (dn->inode_page) {
1035                 if (!dn->inode_page_locked)
1036                         lock_page(dn->inode_page);
1037                 update_inode(dn->inode, dn->inode_page);
1038                 if (!dn->inode_page_locked)
1039                         unlock_page(dn->inode_page);
1040         } else {
1041                 update_inode_page(dn->inode);
1042         }
1043 }
1044
1045 int sync_node_pages(struct f2fs_sb_info *sbi, nid_t ino,
1046                                         struct writeback_control *wbc)
1047 {
1048         pgoff_t index, end;
1049         struct pagevec pvec;
1050         int step = ino ? 2 : 0;
1051         int nwritten = 0, wrote = 0;
1052
1053         pagevec_init(&pvec, 0);
1054
1055 next_step:
1056         index = 0;
1057         end = LONG_MAX;
1058
1059         while (index <= end) {
1060                 int i, nr_pages;
1061                 nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index,
1062                                 PAGECACHE_TAG_DIRTY,
1063                                 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
1064                 if (nr_pages == 0)
1065                         break;
1066
1067                 for (i = 0; i < nr_pages; i++) {
1068                         struct page *page = pvec.pages[i];
1069
1070                         /*
1071                          * flushing sequence with step:
1072                          * 0. indirect nodes
1073                          * 1. dentry dnodes
1074                          * 2. file dnodes
1075                          */
1076                         if (step == 0 && IS_DNODE(page))
1077                                 continue;
1078                         if (step == 1 && (!IS_DNODE(page) ||
1079                                                 is_cold_node(page)))
1080                                 continue;
1081                         if (step == 2 && (!IS_DNODE(page) ||
1082                                                 !is_cold_node(page)))
1083                                 continue;
1084
1085                         /*
1086                          * If an fsync mode,
1087                          * we should not skip writing node pages.
1088                          */
1089                         if (ino && ino_of_node(page) == ino)
1090                                 lock_page(page);
1091                         else if (!trylock_page(page))
1092                                 continue;
1093
1094                         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
1095 continue_unlock:
1096                                 unlock_page(page);
1097                                 continue;
1098                         }
1099                         if (ino && ino_of_node(page) != ino)
1100                                 goto continue_unlock;
1101
1102                         if (!PageDirty(page)) {
1103                                 /* someone wrote it for us */
1104                                 goto continue_unlock;
1105                         }
1106
1107                         if (!clear_page_dirty_for_io(page))
1108                                 goto continue_unlock;
1109
1110                         /* called by fsync() */
1111                         if (ino && IS_DNODE(page)) {
1112                                 int mark = !is_checkpointed_node(sbi, ino);
1113                                 set_fsync_mark(page, 1);
1114                                 if (IS_INODE(page))
1115                                         set_dentry_mark(page, mark);
1116                                 nwritten++;
1117                         } else {
1118                                 set_fsync_mark(page, 0);
1119                                 set_dentry_mark(page, 0);
1120                         }
1121                         NODE_MAPPING(sbi)->a_ops->writepage(page, wbc);
1122                         wrote++;
1123
1124                         if (--wbc->nr_to_write == 0)
1125                                 break;
1126                 }
1127                 pagevec_release(&pvec);
1128                 cond_resched();
1129
1130                 if (wbc->nr_to_write == 0) {
1131                         step = 2;
1132                         break;
1133                 }
1134         }
1135
1136         if (step < 2) {
1137                 step++;
1138                 goto next_step;
1139         }
1140
1141         if (wrote)
1142                 f2fs_submit_merged_bio(sbi, NODE, WRITE);
1143         return nwritten;
1144 }
1145
1146 int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
1147 {
1148         pgoff_t index = 0, end = LONG_MAX;
1149         struct pagevec pvec;
1150         int ret2 = 0, ret = 0;
1151
1152         pagevec_init(&pvec, 0);
1153
1154         while (index <= end) {
1155                 int i, nr_pages;
1156                 nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index,
1157                                 PAGECACHE_TAG_WRITEBACK,
1158                                 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
1159                 if (nr_pages == 0)
1160                         break;
1161
1162                 for (i = 0; i < nr_pages; i++) {
1163                         struct page *page = pvec.pages[i];
1164
1165                         /* until radix tree lookup accepts end_index */
1166                         if (unlikely(page->index > end))
1167                                 continue;
1168
1169                         if (ino && ino_of_node(page) == ino) {
1170                                 f2fs_wait_on_page_writeback(page, NODE);
1171                                 if (TestClearPageError(page))
1172                                         ret = -EIO;
1173                         }
1174                 }
1175                 pagevec_release(&pvec);
1176                 cond_resched();
1177         }
1178
1179         if (unlikely(test_and_clear_bit(AS_ENOSPC, &NODE_MAPPING(sbi)->flags)))
1180                 ret2 = -ENOSPC;
1181         if (unlikely(test_and_clear_bit(AS_EIO, &NODE_MAPPING(sbi)->flags)))
1182                 ret2 = -EIO;
1183         if (!ret)
1184                 ret = ret2;
1185         return ret;
1186 }
1187
1188 static int f2fs_write_node_page(struct page *page,
1189                                 struct writeback_control *wbc)
1190 {
1191         struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
1192         nid_t nid;
1193         block_t new_addr;
1194         struct node_info ni;
1195         struct f2fs_io_info fio = {
1196                 .type = NODE,
1197                 .rw = (wbc->sync_mode == WB_SYNC_ALL) ? WRITE_SYNC : WRITE,
1198         };
1199
1200         trace_f2fs_writepage(page, NODE);
1201
1202         if (unlikely(sbi->por_doing))
1203                 goto redirty_out;
1204
1205         f2fs_wait_on_page_writeback(page, NODE);
1206
1207         /* get old block addr of this node page */
1208         nid = nid_of_node(page);
1209         f2fs_bug_on(page->index != nid);
1210
1211         get_node_info(sbi, nid, &ni);
1212
1213         /* This page is already truncated */
1214         if (unlikely(ni.blk_addr == NULL_ADDR)) {
1215                 dec_page_count(sbi, F2FS_DIRTY_NODES);
1216                 unlock_page(page);
1217                 return 0;
1218         }
1219
1220         if (wbc->for_reclaim)
1221                 goto redirty_out;
1222
1223         mutex_lock(&sbi->node_write);
1224         set_page_writeback(page);
1225         write_node_page(sbi, page, &fio, nid, ni.blk_addr, &new_addr);
1226         set_node_addr(sbi, &ni, new_addr, is_fsync_dnode(page));
1227         dec_page_count(sbi, F2FS_DIRTY_NODES);
1228         mutex_unlock(&sbi->node_write);
1229         unlock_page(page);
1230         return 0;
1231
1232 redirty_out:
1233         redirty_page_for_writepage(wbc, page);
1234         return AOP_WRITEPAGE_ACTIVATE;
1235 }
1236
1237 static int f2fs_write_node_pages(struct address_space *mapping,
1238                             struct writeback_control *wbc)
1239 {
1240         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
1241         long diff;
1242
1243         trace_f2fs_writepages(mapping->host, wbc, NODE);
1244
1245         /* balancing f2fs's metadata in background */
1246         f2fs_balance_fs_bg(sbi);
1247
1248         /* collect a number of dirty node pages and write together */
1249         if (get_pages(sbi, F2FS_DIRTY_NODES) < nr_pages_to_skip(sbi, NODE))
1250                 goto skip_write;
1251
1252         diff = nr_pages_to_write(sbi, NODE, wbc);
1253         wbc->sync_mode = WB_SYNC_NONE;
1254         sync_node_pages(sbi, 0, wbc);
1255         wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
1256         return 0;
1257
1258 skip_write:
1259         wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_NODES);
1260         return 0;
1261 }
1262
1263 static int f2fs_set_node_page_dirty(struct page *page)
1264 {
1265         struct address_space *mapping = page->mapping;
1266         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
1267
1268         trace_f2fs_set_page_dirty(page, NODE);
1269
1270         SetPageUptodate(page);
1271         if (!PageDirty(page)) {
1272                 __set_page_dirty_nobuffers(page);
1273                 inc_page_count(sbi, F2FS_DIRTY_NODES);
1274                 SetPagePrivate(page);
1275                 return 1;
1276         }
1277         return 0;
1278 }
1279
1280 static void f2fs_invalidate_node_page(struct page *page, unsigned int offset,
1281                                       unsigned int length)
1282 {
1283         struct inode *inode = page->mapping->host;
1284         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1285         if (PageDirty(page))
1286                 dec_page_count(sbi, F2FS_DIRTY_NODES);
1287         ClearPagePrivate(page);
1288 }
1289
1290 static int f2fs_release_node_page(struct page *page, gfp_t wait)
1291 {
1292         ClearPagePrivate(page);
1293         return 1;
1294 }
1295
1296 /*
1297  * Structure of the f2fs node operations
1298  */
1299 const struct address_space_operations f2fs_node_aops = {
1300         .writepage      = f2fs_write_node_page,
1301         .writepages     = f2fs_write_node_pages,
1302         .set_page_dirty = f2fs_set_node_page_dirty,
1303         .invalidatepage = f2fs_invalidate_node_page,
1304         .releasepage    = f2fs_release_node_page,
1305 };
1306
1307 static struct free_nid *__lookup_free_nid_list(struct f2fs_nm_info *nm_i,
1308                                                 nid_t n)
1309 {
1310         return radix_tree_lookup(&nm_i->free_nid_root, n);
1311 }
1312
1313 static void __del_from_free_nid_list(struct f2fs_nm_info *nm_i,
1314                                                 struct free_nid *i)
1315 {
1316         list_del(&i->list);
1317         radix_tree_delete(&nm_i->free_nid_root, i->nid);
1318 }
1319
1320 static int add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build)
1321 {
1322         struct f2fs_nm_info *nm_i = NM_I(sbi);
1323         struct free_nid *i;
1324         struct nat_entry *ne;
1325         bool allocated = false;
1326
1327         if (!available_free_memory(sbi, FREE_NIDS))
1328                 return -1;
1329
1330         /* 0 nid should not be used */
1331         if (unlikely(nid == 0))
1332                 return 0;
1333
1334         if (build) {
1335                 /* do not add allocated nids */
1336                 read_lock(&nm_i->nat_tree_lock);
1337                 ne = __lookup_nat_cache(nm_i, nid);
1338                 if (ne &&
1339                         (!ne->checkpointed || nat_get_blkaddr(ne) != NULL_ADDR))
1340                         allocated = true;
1341                 read_unlock(&nm_i->nat_tree_lock);
1342                 if (allocated)
1343                         return 0;
1344         }
1345
1346         i = f2fs_kmem_cache_alloc(free_nid_slab, GFP_NOFS);
1347         i->nid = nid;
1348         i->state = NID_NEW;
1349
1350         spin_lock(&nm_i->free_nid_list_lock);
1351         if (radix_tree_insert(&nm_i->free_nid_root, i->nid, i)) {
1352                 spin_unlock(&nm_i->free_nid_list_lock);
1353                 kmem_cache_free(free_nid_slab, i);
1354                 return 0;
1355         }
1356         list_add_tail(&i->list, &nm_i->free_nid_list);
1357         nm_i->fcnt++;
1358         spin_unlock(&nm_i->free_nid_list_lock);
1359         return 1;
1360 }
1361
1362 static void remove_free_nid(struct f2fs_nm_info *nm_i, nid_t nid)
1363 {
1364         struct free_nid *i;
1365         bool need_free = false;
1366
1367         spin_lock(&nm_i->free_nid_list_lock);
1368         i = __lookup_free_nid_list(nm_i, nid);
1369         if (i && i->state == NID_NEW) {
1370                 __del_from_free_nid_list(nm_i, i);
1371                 nm_i->fcnt--;
1372                 need_free = true;
1373         }
1374         spin_unlock(&nm_i->free_nid_list_lock);
1375
1376         if (need_free)
1377                 kmem_cache_free(free_nid_slab, i);
1378 }
1379
1380 static void scan_nat_page(struct f2fs_sb_info *sbi,
1381                         struct page *nat_page, nid_t start_nid)
1382 {
1383         struct f2fs_nm_info *nm_i = NM_I(sbi);
1384         struct f2fs_nat_block *nat_blk = page_address(nat_page);
1385         block_t blk_addr;
1386         int i;
1387
1388         i = start_nid % NAT_ENTRY_PER_BLOCK;
1389
1390         for (; i < NAT_ENTRY_PER_BLOCK; i++, start_nid++) {
1391
1392                 if (unlikely(start_nid >= nm_i->max_nid))
1393                         break;
1394
1395                 blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr);
1396                 f2fs_bug_on(blk_addr == NEW_ADDR);
1397                 if (blk_addr == NULL_ADDR) {
1398                         if (add_free_nid(sbi, start_nid, true) < 0)
1399                                 break;
1400                 }
1401         }
1402 }
1403
1404 static void build_free_nids(struct f2fs_sb_info *sbi)
1405 {
1406         struct f2fs_nm_info *nm_i = NM_I(sbi);
1407         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1408         struct f2fs_summary_block *sum = curseg->sum_blk;
1409         int i = 0;
1410         nid_t nid = nm_i->next_scan_nid;
1411
1412         /* Enough entries */
1413         if (nm_i->fcnt > NAT_ENTRY_PER_BLOCK)
1414                 return;
1415
1416         /* readahead nat pages to be scanned */
1417         ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), FREE_NID_PAGES, META_NAT);
1418
1419         while (1) {
1420                 struct page *page = get_current_nat_page(sbi, nid);
1421
1422                 scan_nat_page(sbi, page, nid);
1423                 f2fs_put_page(page, 1);
1424
1425                 nid += (NAT_ENTRY_PER_BLOCK - (nid % NAT_ENTRY_PER_BLOCK));
1426                 if (unlikely(nid >= nm_i->max_nid))
1427                         nid = 0;
1428
1429                 if (i++ == FREE_NID_PAGES)
1430                         break;
1431         }
1432
1433         /* go to the next free nat pages to find free nids abundantly */
1434         nm_i->next_scan_nid = nid;
1435
1436         /* find free nids from current sum_pages */
1437         mutex_lock(&curseg->curseg_mutex);
1438         for (i = 0; i < nats_in_cursum(sum); i++) {
1439                 block_t addr = le32_to_cpu(nat_in_journal(sum, i).block_addr);
1440                 nid = le32_to_cpu(nid_in_journal(sum, i));
1441                 if (addr == NULL_ADDR)
1442                         add_free_nid(sbi, nid, true);
1443                 else
1444                         remove_free_nid(nm_i, nid);
1445         }
1446         mutex_unlock(&curseg->curseg_mutex);
1447 }
1448
1449 /*
1450  * If this function returns success, caller can obtain a new nid
1451  * from second parameter of this function.
1452  * The returned nid could be used ino as well as nid when inode is created.
1453  */
1454 bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid)
1455 {
1456         struct f2fs_nm_info *nm_i = NM_I(sbi);
1457         struct free_nid *i = NULL;
1458 retry:
1459         if (unlikely(sbi->total_valid_node_count + 1 > nm_i->available_nids))
1460                 return false;
1461
1462         spin_lock(&nm_i->free_nid_list_lock);
1463
1464         /* We should not use stale free nids created by build_free_nids */
1465         if (nm_i->fcnt && !on_build_free_nids(nm_i)) {
1466                 f2fs_bug_on(list_empty(&nm_i->free_nid_list));
1467                 list_for_each_entry(i, &nm_i->free_nid_list, list)
1468                         if (i->state == NID_NEW)
1469                                 break;
1470
1471                 f2fs_bug_on(i->state != NID_NEW);
1472                 *nid = i->nid;
1473                 i->state = NID_ALLOC;
1474                 nm_i->fcnt--;
1475                 spin_unlock(&nm_i->free_nid_list_lock);
1476                 return true;
1477         }
1478         spin_unlock(&nm_i->free_nid_list_lock);
1479
1480         /* Let's scan nat pages and its caches to get free nids */
1481         mutex_lock(&nm_i->build_lock);
1482         build_free_nids(sbi);
1483         mutex_unlock(&nm_i->build_lock);
1484         goto retry;
1485 }
1486
1487 /*
1488  * alloc_nid() should be called prior to this function.
1489  */
1490 void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid)
1491 {
1492         struct f2fs_nm_info *nm_i = NM_I(sbi);
1493         struct free_nid *i;
1494
1495         spin_lock(&nm_i->free_nid_list_lock);
1496         i = __lookup_free_nid_list(nm_i, nid);
1497         f2fs_bug_on(!i || i->state != NID_ALLOC);
1498         __del_from_free_nid_list(nm_i, i);
1499         spin_unlock(&nm_i->free_nid_list_lock);
1500
1501         kmem_cache_free(free_nid_slab, i);
1502 }
1503
1504 /*
1505  * alloc_nid() should be called prior to this function.
1506  */
1507 void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid)
1508 {
1509         struct f2fs_nm_info *nm_i = NM_I(sbi);
1510         struct free_nid *i;
1511         bool need_free = false;
1512
1513         if (!nid)
1514                 return;
1515
1516         spin_lock(&nm_i->free_nid_list_lock);
1517         i = __lookup_free_nid_list(nm_i, nid);
1518         f2fs_bug_on(!i || i->state != NID_ALLOC);
1519         if (!available_free_memory(sbi, FREE_NIDS)) {
1520                 __del_from_free_nid_list(nm_i, i);
1521                 need_free = true;
1522         } else {
1523                 i->state = NID_NEW;
1524                 nm_i->fcnt++;
1525         }
1526         spin_unlock(&nm_i->free_nid_list_lock);
1527
1528         if (need_free)
1529                 kmem_cache_free(free_nid_slab, i);
1530 }
1531
1532 void recover_node_page(struct f2fs_sb_info *sbi, struct page *page,
1533                 struct f2fs_summary *sum, struct node_info *ni,
1534                 block_t new_blkaddr)
1535 {
1536         rewrite_node_page(sbi, page, sum, ni->blk_addr, new_blkaddr);
1537         set_node_addr(sbi, ni, new_blkaddr, false);
1538         clear_node_page_dirty(page);
1539 }
1540
1541 static void recover_inline_xattr(struct inode *inode, struct page *page)
1542 {
1543         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1544         void *src_addr, *dst_addr;
1545         size_t inline_size;
1546         struct page *ipage;
1547         struct f2fs_inode *ri;
1548
1549         if (!f2fs_has_inline_xattr(inode))
1550                 return;
1551
1552         if (!IS_INODE(page))
1553                 return;
1554
1555         ri = F2FS_INODE(page);
1556         if (!(ri->i_inline & F2FS_INLINE_XATTR))
1557                 return;
1558
1559         ipage = get_node_page(sbi, inode->i_ino);
1560         f2fs_bug_on(IS_ERR(ipage));
1561
1562         dst_addr = inline_xattr_addr(ipage);
1563         src_addr = inline_xattr_addr(page);
1564         inline_size = inline_xattr_size(inode);
1565
1566         f2fs_wait_on_page_writeback(ipage, NODE);
1567         memcpy(dst_addr, src_addr, inline_size);
1568
1569         update_inode(inode, ipage);
1570         f2fs_put_page(ipage, 1);
1571 }
1572
1573 bool recover_xattr_data(struct inode *inode, struct page *page, block_t blkaddr)
1574 {
1575         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1576         nid_t prev_xnid = F2FS_I(inode)->i_xattr_nid;
1577         nid_t new_xnid = nid_of_node(page);
1578         struct node_info ni;
1579
1580         recover_inline_xattr(inode, page);
1581
1582         if (!f2fs_has_xattr_block(ofs_of_node(page)))
1583                 return false;
1584
1585         /* 1: invalidate the previous xattr nid */
1586         if (!prev_xnid)
1587                 goto recover_xnid;
1588
1589         /* Deallocate node address */
1590         get_node_info(sbi, prev_xnid, &ni);
1591         f2fs_bug_on(ni.blk_addr == NULL_ADDR);
1592         invalidate_blocks(sbi, ni.blk_addr);
1593         dec_valid_node_count(sbi, inode);
1594         set_node_addr(sbi, &ni, NULL_ADDR, false);
1595
1596 recover_xnid:
1597         /* 2: allocate new xattr nid */
1598         if (unlikely(!inc_valid_node_count(sbi, inode)))
1599                 f2fs_bug_on(1);
1600
1601         remove_free_nid(NM_I(sbi), new_xnid);
1602         get_node_info(sbi, new_xnid, &ni);
1603         ni.ino = inode->i_ino;
1604         set_node_addr(sbi, &ni, NEW_ADDR, false);
1605         F2FS_I(inode)->i_xattr_nid = new_xnid;
1606
1607         /* 3: update xattr blkaddr */
1608         refresh_sit_entry(sbi, NEW_ADDR, blkaddr);
1609         set_node_addr(sbi, &ni, blkaddr, false);
1610
1611         update_inode_page(inode);
1612         return true;
1613 }
1614
1615 int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
1616 {
1617         struct f2fs_inode *src, *dst;
1618         nid_t ino = ino_of_node(page);
1619         struct node_info old_ni, new_ni;
1620         struct page *ipage;
1621
1622         get_node_info(sbi, ino, &old_ni);
1623
1624         if (unlikely(old_ni.blk_addr != NULL_ADDR))
1625                 return -EINVAL;
1626
1627         ipage = grab_cache_page(NODE_MAPPING(sbi), ino);
1628         if (!ipage)
1629                 return -ENOMEM;
1630
1631         /* Should not use this inode  from free nid list */
1632         remove_free_nid(NM_I(sbi), ino);
1633
1634         SetPageUptodate(ipage);
1635         fill_node_footer(ipage, ino, ino, 0, true);
1636
1637         src = F2FS_INODE(page);
1638         dst = F2FS_INODE(ipage);
1639
1640         memcpy(dst, src, (unsigned long)&src->i_ext - (unsigned long)src);
1641         dst->i_size = 0;
1642         dst->i_blocks = cpu_to_le64(1);
1643         dst->i_links = cpu_to_le32(1);
1644         dst->i_xattr_nid = 0;
1645
1646         new_ni = old_ni;
1647         new_ni.ino = ino;
1648
1649         if (unlikely(!inc_valid_node_count(sbi, NULL)))
1650                 WARN_ON(1);
1651         set_node_addr(sbi, &new_ni, NEW_ADDR, false);
1652         inc_valid_inode_count(sbi);
1653         f2fs_put_page(ipage, 1);
1654         return 0;
1655 }
1656
1657 /*
1658  * ra_sum_pages() merge contiguous pages into one bio and submit.
1659  * these pre-readed pages are linked in pages list.
1660  */
1661 static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages,
1662                                 int start, int nrpages)
1663 {
1664         struct page *page;
1665         int page_idx = start;
1666         struct f2fs_io_info fio = {
1667                 .type = META,
1668                 .rw = READ_SYNC | REQ_META | REQ_PRIO
1669         };
1670
1671         for (; page_idx < start + nrpages; page_idx++) {
1672                 /* alloc temporal page for read node summary info*/
1673                 page = alloc_page(GFP_F2FS_ZERO);
1674                 if (!page)
1675                         break;
1676
1677                 lock_page(page);
1678                 page->index = page_idx;
1679                 list_add_tail(&page->lru, pages);
1680         }
1681
1682         list_for_each_entry(page, pages, lru)
1683                 f2fs_submit_page_mbio(sbi, page, page->index, &fio);
1684
1685         f2fs_submit_merged_bio(sbi, META, READ);
1686
1687         return page_idx - start;
1688 }
1689
1690 int restore_node_summary(struct f2fs_sb_info *sbi,
1691                         unsigned int segno, struct f2fs_summary_block *sum)
1692 {
1693         struct f2fs_node *rn;
1694         struct f2fs_summary *sum_entry;
1695         struct page *page, *tmp;
1696         block_t addr;
1697         int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
1698         int i, last_offset, nrpages, err = 0;
1699         LIST_HEAD(page_list);
1700
1701         /* scan the node segment */
1702         last_offset = sbi->blocks_per_seg;
1703         addr = START_BLOCK(sbi, segno);
1704         sum_entry = &sum->entries[0];
1705
1706         for (i = 0; !err && i < last_offset; i += nrpages, addr += nrpages) {
1707                 nrpages = min(last_offset - i, bio_blocks);
1708
1709                 /* read ahead node pages */
1710                 nrpages = ra_sum_pages(sbi, &page_list, addr, nrpages);
1711                 if (!nrpages)
1712                         return -ENOMEM;
1713
1714                 list_for_each_entry_safe(page, tmp, &page_list, lru) {
1715                         if (err)
1716                                 goto skip;
1717
1718                         lock_page(page);
1719                         if (unlikely(!PageUptodate(page))) {
1720                                 err = -EIO;
1721                         } else {
1722                                 rn = F2FS_NODE(page);
1723                                 sum_entry->nid = rn->footer.nid;
1724                                 sum_entry->version = 0;
1725                                 sum_entry->ofs_in_node = 0;
1726                                 sum_entry++;
1727                         }
1728                         unlock_page(page);
1729 skip:
1730                         list_del(&page->lru);
1731                         __free_pages(page, 0);
1732                 }
1733         }
1734         return err;
1735 }
1736
1737 static bool flush_nats_in_journal(struct f2fs_sb_info *sbi)
1738 {
1739         struct f2fs_nm_info *nm_i = NM_I(sbi);
1740         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1741         struct f2fs_summary_block *sum = curseg->sum_blk;
1742         int i;
1743
1744         mutex_lock(&curseg->curseg_mutex);
1745
1746         if (nats_in_cursum(sum) < NAT_JOURNAL_ENTRIES) {
1747                 mutex_unlock(&curseg->curseg_mutex);
1748                 return false;
1749         }
1750
1751         for (i = 0; i < nats_in_cursum(sum); i++) {
1752                 struct nat_entry *ne;
1753                 struct f2fs_nat_entry raw_ne;
1754                 nid_t nid = le32_to_cpu(nid_in_journal(sum, i));
1755
1756                 raw_ne = nat_in_journal(sum, i);
1757 retry:
1758                 write_lock(&nm_i->nat_tree_lock);
1759                 ne = __lookup_nat_cache(nm_i, nid);
1760                 if (ne) {
1761                         __set_nat_cache_dirty(nm_i, ne);
1762                         write_unlock(&nm_i->nat_tree_lock);
1763                         continue;
1764                 }
1765                 ne = grab_nat_entry(nm_i, nid);
1766                 if (!ne) {
1767                         write_unlock(&nm_i->nat_tree_lock);
1768                         goto retry;
1769                 }
1770                 node_info_from_raw_nat(&ne->ni, &raw_ne);
1771                 __set_nat_cache_dirty(nm_i, ne);
1772                 write_unlock(&nm_i->nat_tree_lock);
1773         }
1774         update_nats_in_cursum(sum, -i);
1775         mutex_unlock(&curseg->curseg_mutex);
1776         return true;
1777 }
1778
1779 /*
1780  * This function is called during the checkpointing process.
1781  */
1782 void flush_nat_entries(struct f2fs_sb_info *sbi)
1783 {
1784         struct f2fs_nm_info *nm_i = NM_I(sbi);
1785         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1786         struct f2fs_summary_block *sum = curseg->sum_blk;
1787         struct nat_entry *ne, *cur;
1788         struct page *page = NULL;
1789         struct f2fs_nat_block *nat_blk = NULL;
1790         nid_t start_nid = 0, end_nid = 0;
1791         bool flushed;
1792
1793         flushed = flush_nats_in_journal(sbi);
1794
1795         if (!flushed)
1796                 mutex_lock(&curseg->curseg_mutex);
1797
1798         /* 1) flush dirty nat caches */
1799         list_for_each_entry_safe(ne, cur, &nm_i->dirty_nat_entries, list) {
1800                 nid_t nid;
1801                 struct f2fs_nat_entry raw_ne;
1802                 int offset = -1;
1803
1804                 if (nat_get_blkaddr(ne) == NEW_ADDR)
1805                         continue;
1806
1807                 nid = nat_get_nid(ne);
1808
1809                 if (flushed)
1810                         goto to_nat_page;
1811
1812                 /* if there is room for nat enries in curseg->sumpage */
1813                 offset = lookup_journal_in_cursum(sum, NAT_JOURNAL, nid, 1);
1814                 if (offset >= 0) {
1815                         raw_ne = nat_in_journal(sum, offset);
1816                         goto flush_now;
1817                 }
1818 to_nat_page:
1819                 if (!page || (start_nid > nid || nid > end_nid)) {
1820                         if (page) {
1821                                 f2fs_put_page(page, 1);
1822                                 page = NULL;
1823                         }
1824                         start_nid = START_NID(nid);
1825                         end_nid = start_nid + NAT_ENTRY_PER_BLOCK - 1;
1826
1827                         /*
1828                          * get nat block with dirty flag, increased reference
1829                          * count, mapped and lock
1830                          */
1831                         page = get_next_nat_page(sbi, start_nid);
1832                         nat_blk = page_address(page);
1833                 }
1834
1835                 f2fs_bug_on(!nat_blk);
1836                 raw_ne = nat_blk->entries[nid - start_nid];
1837 flush_now:
1838                 raw_nat_from_node_info(&raw_ne, &ne->ni);
1839
1840                 if (offset < 0) {
1841                         nat_blk->entries[nid - start_nid] = raw_ne;
1842                 } else {
1843                         nat_in_journal(sum, offset) = raw_ne;
1844                         nid_in_journal(sum, offset) = cpu_to_le32(nid);
1845                 }
1846
1847                 if (nat_get_blkaddr(ne) == NULL_ADDR &&
1848                                 add_free_nid(sbi, nid, false) <= 0) {
1849                         write_lock(&nm_i->nat_tree_lock);
1850                         __del_from_nat_cache(nm_i, ne);
1851                         write_unlock(&nm_i->nat_tree_lock);
1852                 } else {
1853                         write_lock(&nm_i->nat_tree_lock);
1854                         __clear_nat_cache_dirty(nm_i, ne);
1855                         write_unlock(&nm_i->nat_tree_lock);
1856                 }
1857         }
1858         if (!flushed)
1859                 mutex_unlock(&curseg->curseg_mutex);
1860         f2fs_put_page(page, 1);
1861 }
1862
1863 static int init_node_manager(struct f2fs_sb_info *sbi)
1864 {
1865         struct f2fs_super_block *sb_raw = F2FS_RAW_SUPER(sbi);
1866         struct f2fs_nm_info *nm_i = NM_I(sbi);
1867         unsigned char *version_bitmap;
1868         unsigned int nat_segs, nat_blocks;
1869
1870         nm_i->nat_blkaddr = le32_to_cpu(sb_raw->nat_blkaddr);
1871
1872         /* segment_count_nat includes pair segment so divide to 2. */
1873         nat_segs = le32_to_cpu(sb_raw->segment_count_nat) >> 1;
1874         nat_blocks = nat_segs << le32_to_cpu(sb_raw->log_blocks_per_seg);
1875
1876         nm_i->max_nid = NAT_ENTRY_PER_BLOCK * nat_blocks;
1877
1878         /* not used nids: 0, node, meta, (and root counted as valid node) */
1879         nm_i->available_nids = nm_i->max_nid - 3;
1880         nm_i->fcnt = 0;
1881         nm_i->nat_cnt = 0;
1882         nm_i->ram_thresh = DEF_RAM_THRESHOLD;
1883
1884         INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC);
1885         INIT_LIST_HEAD(&nm_i->free_nid_list);
1886         INIT_RADIX_TREE(&nm_i->nat_root, GFP_ATOMIC);
1887         INIT_LIST_HEAD(&nm_i->nat_entries);
1888         INIT_LIST_HEAD(&nm_i->dirty_nat_entries);
1889
1890         mutex_init(&nm_i->build_lock);
1891         spin_lock_init(&nm_i->free_nid_list_lock);
1892         rwlock_init(&nm_i->nat_tree_lock);
1893
1894         nm_i->next_scan_nid = le32_to_cpu(sbi->ckpt->next_free_nid);
1895         nm_i->bitmap_size = __bitmap_size(sbi, NAT_BITMAP);
1896         version_bitmap = __bitmap_ptr(sbi, NAT_BITMAP);
1897         if (!version_bitmap)
1898                 return -EFAULT;
1899
1900         nm_i->nat_bitmap = kmemdup(version_bitmap, nm_i->bitmap_size,
1901                                         GFP_KERNEL);
1902         if (!nm_i->nat_bitmap)
1903                 return -ENOMEM;
1904         return 0;
1905 }
1906
1907 int build_node_manager(struct f2fs_sb_info *sbi)
1908 {
1909         int err;
1910
1911         sbi->nm_info = kzalloc(sizeof(struct f2fs_nm_info), GFP_KERNEL);
1912         if (!sbi->nm_info)
1913                 return -ENOMEM;
1914
1915         err = init_node_manager(sbi);
1916         if (err)
1917                 return err;
1918
1919         build_free_nids(sbi);
1920         return 0;
1921 }
1922
1923 void destroy_node_manager(struct f2fs_sb_info *sbi)
1924 {
1925         struct f2fs_nm_info *nm_i = NM_I(sbi);
1926         struct free_nid *i, *next_i;
1927         struct nat_entry *natvec[NATVEC_SIZE];
1928         nid_t nid = 0;
1929         unsigned int found;
1930
1931         if (!nm_i)
1932                 return;
1933
1934         /* destroy free nid list */
1935         spin_lock(&nm_i->free_nid_list_lock);
1936         list_for_each_entry_safe(i, next_i, &nm_i->free_nid_list, list) {
1937                 f2fs_bug_on(i->state == NID_ALLOC);
1938                 __del_from_free_nid_list(nm_i, i);
1939                 nm_i->fcnt--;
1940                 spin_unlock(&nm_i->free_nid_list_lock);
1941                 kmem_cache_free(free_nid_slab, i);
1942                 spin_lock(&nm_i->free_nid_list_lock);
1943         }
1944         f2fs_bug_on(nm_i->fcnt);
1945         spin_unlock(&nm_i->free_nid_list_lock);
1946
1947         /* destroy nat cache */
1948         write_lock(&nm_i->nat_tree_lock);
1949         while ((found = __gang_lookup_nat_cache(nm_i,
1950                                         nid, NATVEC_SIZE, natvec))) {
1951                 unsigned idx;
1952                 nid = nat_get_nid(natvec[found - 1]) + 1;
1953                 for (idx = 0; idx < found; idx++)
1954                         __del_from_nat_cache(nm_i, natvec[idx]);
1955         }
1956         f2fs_bug_on(nm_i->nat_cnt);
1957         write_unlock(&nm_i->nat_tree_lock);
1958
1959         kfree(nm_i->nat_bitmap);
1960         sbi->nm_info = NULL;
1961         kfree(nm_i);
1962 }
1963
1964 int __init create_node_manager_caches(void)
1965 {
1966         nat_entry_slab = f2fs_kmem_cache_create("nat_entry",
1967                         sizeof(struct nat_entry));
1968         if (!nat_entry_slab)
1969                 return -ENOMEM;
1970
1971         free_nid_slab = f2fs_kmem_cache_create("free_nid",
1972                         sizeof(struct free_nid));
1973         if (!free_nid_slab) {
1974                 kmem_cache_destroy(nat_entry_slab);
1975                 return -ENOMEM;
1976         }
1977         return 0;
1978 }
1979
1980 void destroy_node_manager_caches(void)
1981 {
1982         kmem_cache_destroy(free_nid_slab);
1983         kmem_cache_destroy(nat_entry_slab);
1984 }