1db5ebe6692e77839f77222ee9a9be789dd8019a
[linux-2.6-microblaze.git] / fs / f2fs / super.c
1 /*
2  * fs/f2fs/super.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/module.h>
12 #include <linux/init.h>
13 #include <linux/fs.h>
14 #include <linux/statfs.h>
15 #include <linux/proc_fs.h>
16 #include <linux/buffer_head.h>
17 #include <linux/backing-dev.h>
18 #include <linux/kthread.h>
19 #include <linux/parser.h>
20 #include <linux/mount.h>
21 #include <linux/seq_file.h>
22 #include <linux/random.h>
23 #include <linux/exportfs.h>
24 #include <linux/blkdev.h>
25 #include <linux/f2fs_fs.h>
26
27 #include "f2fs.h"
28 #include "node.h"
29 #include "xattr.h"
30
31 static struct kmem_cache *f2fs_inode_cachep;
32
33 enum {
34         Opt_gc_background_off,
35         Opt_disable_roll_forward,
36         Opt_discard,
37         Opt_noheap,
38         Opt_nouser_xattr,
39         Opt_noacl,
40         Opt_active_logs,
41         Opt_disable_ext_identify,
42         Opt_err,
43 };
44
45 static match_table_t f2fs_tokens = {
46         {Opt_gc_background_off, "background_gc_off"},
47         {Opt_disable_roll_forward, "disable_roll_forward"},
48         {Opt_discard, "discard"},
49         {Opt_noheap, "no_heap"},
50         {Opt_nouser_xattr, "nouser_xattr"},
51         {Opt_noacl, "noacl"},
52         {Opt_active_logs, "active_logs=%u"},
53         {Opt_disable_ext_identify, "disable_ext_identify"},
54         {Opt_err, NULL},
55 };
56
57 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
58 {
59         struct va_format vaf;
60         va_list args;
61
62         va_start(args, fmt);
63         vaf.fmt = fmt;
64         vaf.va = &args;
65         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
66         va_end(args);
67 }
68
69 static void init_once(void *foo)
70 {
71         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
72
73         inode_init_once(&fi->vfs_inode);
74 }
75
76 static struct inode *f2fs_alloc_inode(struct super_block *sb)
77 {
78         struct f2fs_inode_info *fi;
79
80         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
81         if (!fi)
82                 return NULL;
83
84         init_once((void *) fi);
85
86         /* Initilize f2fs-specific inode info */
87         fi->vfs_inode.i_version = 1;
88         atomic_set(&fi->dirty_dents, 0);
89         fi->i_current_depth = 1;
90         fi->i_advise = 0;
91         rwlock_init(&fi->ext.ext_lock);
92
93         set_inode_flag(fi, FI_NEW_INODE);
94
95         return &fi->vfs_inode;
96 }
97
98 static void f2fs_i_callback(struct rcu_head *head)
99 {
100         struct inode *inode = container_of(head, struct inode, i_rcu);
101         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
102 }
103
104 static void f2fs_destroy_inode(struct inode *inode)
105 {
106         call_rcu(&inode->i_rcu, f2fs_i_callback);
107 }
108
109 static void f2fs_put_super(struct super_block *sb)
110 {
111         struct f2fs_sb_info *sbi = F2FS_SB(sb);
112
113         f2fs_destroy_stats(sbi);
114         stop_gc_thread(sbi);
115
116         write_checkpoint(sbi, true);
117
118         iput(sbi->node_inode);
119         iput(sbi->meta_inode);
120
121         /* destroy f2fs internal modules */
122         destroy_node_manager(sbi);
123         destroy_segment_manager(sbi);
124
125         kfree(sbi->ckpt);
126
127         sb->s_fs_info = NULL;
128         brelse(sbi->raw_super_buf);
129         kfree(sbi);
130 }
131
132 int f2fs_sync_fs(struct super_block *sb, int sync)
133 {
134         struct f2fs_sb_info *sbi = F2FS_SB(sb);
135
136         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
137                 return 0;
138
139         if (sync)
140                 write_checkpoint(sbi, false);
141         else
142                 f2fs_balance_fs(sbi);
143
144         return 0;
145 }
146
147 static int f2fs_freeze(struct super_block *sb)
148 {
149         int err;
150
151         if (sb->s_flags & MS_RDONLY)
152                 return 0;
153
154         err = f2fs_sync_fs(sb, 1);
155         return err;
156 }
157
158 static int f2fs_unfreeze(struct super_block *sb)
159 {
160         return 0;
161 }
162
163 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
164 {
165         struct super_block *sb = dentry->d_sb;
166         struct f2fs_sb_info *sbi = F2FS_SB(sb);
167         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
168         block_t total_count, user_block_count, start_count, ovp_count;
169
170         total_count = le64_to_cpu(sbi->raw_super->block_count);
171         user_block_count = sbi->user_block_count;
172         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
173         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
174         buf->f_type = F2FS_SUPER_MAGIC;
175         buf->f_bsize = sbi->blocksize;
176
177         buf->f_blocks = total_count - start_count;
178         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
179         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
180
181         buf->f_files = sbi->total_node_count;
182         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
183
184         buf->f_namelen = F2FS_NAME_LEN;
185         buf->f_fsid.val[0] = (u32)id;
186         buf->f_fsid.val[1] = (u32)(id >> 32);
187
188         return 0;
189 }
190
191 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
192 {
193         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
194
195         if (test_opt(sbi, BG_GC))
196                 seq_puts(seq, ",background_gc_on");
197         else
198                 seq_puts(seq, ",background_gc_off");
199         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
200                 seq_puts(seq, ",disable_roll_forward");
201         if (test_opt(sbi, DISCARD))
202                 seq_puts(seq, ",discard");
203         if (test_opt(sbi, NOHEAP))
204                 seq_puts(seq, ",no_heap_alloc");
205 #ifdef CONFIG_F2FS_FS_XATTR
206         if (test_opt(sbi, XATTR_USER))
207                 seq_puts(seq, ",user_xattr");
208         else
209                 seq_puts(seq, ",nouser_xattr");
210 #endif
211 #ifdef CONFIG_F2FS_FS_POSIX_ACL
212         if (test_opt(sbi, POSIX_ACL))
213                 seq_puts(seq, ",acl");
214         else
215                 seq_puts(seq, ",noacl");
216 #endif
217         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
218                 seq_puts(seq, ",disable_ext_identify");
219
220         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
221
222         return 0;
223 }
224
225 static struct super_operations f2fs_sops = {
226         .alloc_inode    = f2fs_alloc_inode,
227         .destroy_inode  = f2fs_destroy_inode,
228         .write_inode    = f2fs_write_inode,
229         .show_options   = f2fs_show_options,
230         .evict_inode    = f2fs_evict_inode,
231         .put_super      = f2fs_put_super,
232         .sync_fs        = f2fs_sync_fs,
233         .freeze_fs      = f2fs_freeze,
234         .unfreeze_fs    = f2fs_unfreeze,
235         .statfs         = f2fs_statfs,
236 };
237
238 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
239                 u64 ino, u32 generation)
240 {
241         struct f2fs_sb_info *sbi = F2FS_SB(sb);
242         struct inode *inode;
243
244         if (ino < F2FS_ROOT_INO(sbi))
245                 return ERR_PTR(-ESTALE);
246
247         /*
248          * f2fs_iget isn't quite right if the inode is currently unallocated!
249          * However f2fs_iget currently does appropriate checks to handle stale
250          * inodes so everything is OK.
251          */
252         inode = f2fs_iget(sb, ino);
253         if (IS_ERR(inode))
254                 return ERR_CAST(inode);
255         if (generation && inode->i_generation != generation) {
256                 /* we didn't find the right inode.. */
257                 iput(inode);
258                 return ERR_PTR(-ESTALE);
259         }
260         return inode;
261 }
262
263 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
264                 int fh_len, int fh_type)
265 {
266         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
267                                     f2fs_nfs_get_inode);
268 }
269
270 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
271                 int fh_len, int fh_type)
272 {
273         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
274                                     f2fs_nfs_get_inode);
275 }
276
277 static const struct export_operations f2fs_export_ops = {
278         .fh_to_dentry = f2fs_fh_to_dentry,
279         .fh_to_parent = f2fs_fh_to_parent,
280         .get_parent = f2fs_get_parent,
281 };
282
283 static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
284                                 char *options)
285 {
286         substring_t args[MAX_OPT_ARGS];
287         char *p;
288         int arg = 0;
289
290         if (!options)
291                 return 0;
292
293         while ((p = strsep(&options, ",")) != NULL) {
294                 int token;
295                 if (!*p)
296                         continue;
297                 /*
298                  * Initialize args struct so we know whether arg was
299                  * found; some options take optional arguments.
300                  */
301                 args[0].to = args[0].from = NULL;
302                 token = match_token(p, f2fs_tokens, args);
303
304                 switch (token) {
305                 case Opt_gc_background_off:
306                         clear_opt(sbi, BG_GC);
307                         break;
308                 case Opt_disable_roll_forward:
309                         set_opt(sbi, DISABLE_ROLL_FORWARD);
310                         break;
311                 case Opt_discard:
312                         set_opt(sbi, DISCARD);
313                         break;
314                 case Opt_noheap:
315                         set_opt(sbi, NOHEAP);
316                         break;
317 #ifdef CONFIG_F2FS_FS_XATTR
318                 case Opt_nouser_xattr:
319                         clear_opt(sbi, XATTR_USER);
320                         break;
321 #else
322                 case Opt_nouser_xattr:
323                         f2fs_msg(sb, KERN_INFO,
324                                 "nouser_xattr options not supported");
325                         break;
326 #endif
327 #ifdef CONFIG_F2FS_FS_POSIX_ACL
328                 case Opt_noacl:
329                         clear_opt(sbi, POSIX_ACL);
330                         break;
331 #else
332                 case Opt_noacl:
333                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
334                         break;
335 #endif
336                 case Opt_active_logs:
337                         if (args->from && match_int(args, &arg))
338                                 return -EINVAL;
339                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
340                                 return -EINVAL;
341                         sbi->active_logs = arg;
342                         break;
343                 case Opt_disable_ext_identify:
344                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
345                         break;
346                 default:
347                         f2fs_msg(sb, KERN_ERR,
348                                 "Unrecognized mount option \"%s\" or missing value",
349                                 p);
350                         return -EINVAL;
351                 }
352         }
353         return 0;
354 }
355
356 static loff_t max_file_size(unsigned bits)
357 {
358         loff_t result = ADDRS_PER_INODE;
359         loff_t leaf_count = ADDRS_PER_BLOCK;
360
361         /* two direct node blocks */
362         result += (leaf_count * 2);
363
364         /* two indirect node blocks */
365         leaf_count *= NIDS_PER_BLOCK;
366         result += (leaf_count * 2);
367
368         /* one double indirect node block */
369         leaf_count *= NIDS_PER_BLOCK;
370         result += leaf_count;
371
372         result <<= bits;
373         return result;
374 }
375
376 static int sanity_check_raw_super(struct super_block *sb,
377                         struct f2fs_super_block *raw_super)
378 {
379         unsigned int blocksize;
380
381         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
382                 f2fs_msg(sb, KERN_INFO,
383                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
384                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
385                 return 1;
386         }
387
388         /* Currently, support only 4KB page cache size */
389         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
390                 f2fs_msg(sb, KERN_INFO,
391                         "Invalid page_cache_size (%lu), supports only 4KB\n",
392                         PAGE_CACHE_SIZE);
393                 return 1;
394         }
395
396         /* Currently, support only 4KB block size */
397         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
398         if (blocksize != F2FS_BLKSIZE) {
399                 f2fs_msg(sb, KERN_INFO,
400                         "Invalid blocksize (%u), supports only 4KB\n",
401                         blocksize);
402                 return 1;
403         }
404
405         if (le32_to_cpu(raw_super->log_sectorsize) !=
406                                         F2FS_LOG_SECTOR_SIZE) {
407                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
408                 return 1;
409         }
410         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
411                                         F2FS_LOG_SECTORS_PER_BLOCK) {
412                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
413                 return 1;
414         }
415         return 0;
416 }
417
418 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
419 {
420         unsigned int total, fsmeta;
421         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
422         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
423
424         total = le32_to_cpu(raw_super->segment_count);
425         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
426         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
427         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
428         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
429         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
430
431         if (fsmeta >= total)
432                 return 1;
433
434         if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
435                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
436                 return 1;
437         }
438         return 0;
439 }
440
441 static void init_sb_info(struct f2fs_sb_info *sbi)
442 {
443         struct f2fs_super_block *raw_super = sbi->raw_super;
444         int i;
445
446         sbi->log_sectors_per_block =
447                 le32_to_cpu(raw_super->log_sectors_per_block);
448         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
449         sbi->blocksize = 1 << sbi->log_blocksize;
450         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
451         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
452         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
453         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
454         sbi->total_sections = le32_to_cpu(raw_super->section_count);
455         sbi->total_node_count =
456                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
457                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
458         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
459         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
460         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
461
462         for (i = 0; i < NR_COUNT_TYPE; i++)
463                 atomic_set(&sbi->nr_pages[i], 0);
464 }
465
466 static int validate_superblock(struct super_block *sb,
467                 struct f2fs_super_block **raw_super,
468                 struct buffer_head **raw_super_buf, sector_t block)
469 {
470         const char *super = (block == 0 ? "first" : "second");
471
472         /* read f2fs raw super block */
473         *raw_super_buf = sb_bread(sb, block);
474         if (!*raw_super_buf) {
475                 f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
476                                 super);
477                 return -EIO;
478         }
479
480         *raw_super = (struct f2fs_super_block *)
481                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
482
483         /* sanity checking of raw super */
484         if (!sanity_check_raw_super(sb, *raw_super))
485                 return 0;
486
487         f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
488                                 "in %s superblock", super);
489         return -EINVAL;
490 }
491
492 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
493 {
494         struct f2fs_sb_info *sbi;
495         struct f2fs_super_block *raw_super;
496         struct buffer_head *raw_super_buf;
497         struct inode *root;
498         long err = -EINVAL;
499         int i;
500
501         /* allocate memory for f2fs-specific super block info */
502         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
503         if (!sbi)
504                 return -ENOMEM;
505
506         /* set a block size */
507         if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
508                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
509                 goto free_sbi;
510         }
511
512         err = validate_superblock(sb, &raw_super, &raw_super_buf, 0);
513         if (err) {
514                 brelse(raw_super_buf);
515                 /* check secondary superblock when primary failed */
516                 err = validate_superblock(sb, &raw_super, &raw_super_buf, 1);
517                 if (err)
518                         goto free_sb_buf;
519         }
520         /* init some FS parameters */
521         sbi->active_logs = NR_CURSEG_TYPE;
522
523         set_opt(sbi, BG_GC);
524
525 #ifdef CONFIG_F2FS_FS_XATTR
526         set_opt(sbi, XATTR_USER);
527 #endif
528 #ifdef CONFIG_F2FS_FS_POSIX_ACL
529         set_opt(sbi, POSIX_ACL);
530 #endif
531         /* parse mount options */
532         if (parse_options(sb, sbi, (char *)data))
533                 goto free_sb_buf;
534
535         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
536         sb->s_max_links = F2FS_LINK_MAX;
537         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
538
539         sb->s_op = &f2fs_sops;
540         sb->s_xattr = f2fs_xattr_handlers;
541         sb->s_export_op = &f2fs_export_ops;
542         sb->s_magic = F2FS_SUPER_MAGIC;
543         sb->s_fs_info = sbi;
544         sb->s_time_gran = 1;
545         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
546                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
547         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
548
549         /* init f2fs-specific super block info */
550         sbi->sb = sb;
551         sbi->raw_super = raw_super;
552         sbi->raw_super_buf = raw_super_buf;
553         mutex_init(&sbi->gc_mutex);
554         mutex_init(&sbi->write_inode);
555         mutex_init(&sbi->writepages);
556         mutex_init(&sbi->cp_mutex);
557         for (i = 0; i < NR_LOCK_TYPE; i++)
558                 mutex_init(&sbi->fs_lock[i]);
559         sbi->por_doing = 0;
560         spin_lock_init(&sbi->stat_lock);
561         init_rwsem(&sbi->bio_sem);
562         init_sb_info(sbi);
563
564         /* get an inode for meta space */
565         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
566         if (IS_ERR(sbi->meta_inode)) {
567                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
568                 err = PTR_ERR(sbi->meta_inode);
569                 goto free_sb_buf;
570         }
571
572         err = get_valid_checkpoint(sbi);
573         if (err) {
574                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
575                 goto free_meta_inode;
576         }
577
578         /* sanity checking of checkpoint */
579         err = -EINVAL;
580         if (sanity_check_ckpt(sbi)) {
581                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
582                 goto free_cp;
583         }
584
585         sbi->total_valid_node_count =
586                                 le32_to_cpu(sbi->ckpt->valid_node_count);
587         sbi->total_valid_inode_count =
588                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
589         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
590         sbi->total_valid_block_count =
591                                 le64_to_cpu(sbi->ckpt->valid_block_count);
592         sbi->last_valid_block_count = sbi->total_valid_block_count;
593         sbi->alloc_valid_block_count = 0;
594         INIT_LIST_HEAD(&sbi->dir_inode_list);
595         spin_lock_init(&sbi->dir_inode_lock);
596
597         init_orphan_info(sbi);
598
599         /* setup f2fs internal modules */
600         err = build_segment_manager(sbi);
601         if (err) {
602                 f2fs_msg(sb, KERN_ERR,
603                         "Failed to initialize F2FS segment manager");
604                 goto free_sm;
605         }
606         err = build_node_manager(sbi);
607         if (err) {
608                 f2fs_msg(sb, KERN_ERR,
609                         "Failed to initialize F2FS node manager");
610                 goto free_nm;
611         }
612
613         build_gc_manager(sbi);
614
615         /* get an inode for node space */
616         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
617         if (IS_ERR(sbi->node_inode)) {
618                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
619                 err = PTR_ERR(sbi->node_inode);
620                 goto free_nm;
621         }
622
623         /* if there are nt orphan nodes free them */
624         err = -EINVAL;
625         if (recover_orphan_inodes(sbi))
626                 goto free_node_inode;
627
628         /* read root inode and dentry */
629         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
630         if (IS_ERR(root)) {
631                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
632                 err = PTR_ERR(root);
633                 goto free_node_inode;
634         }
635         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
636                 goto free_root_inode;
637
638         sb->s_root = d_make_root(root); /* allocate root dentry */
639         if (!sb->s_root) {
640                 err = -ENOMEM;
641                 goto free_root_inode;
642         }
643
644         /* recover fsynced data */
645         if (!test_opt(sbi, DISABLE_ROLL_FORWARD))
646                 recover_fsync_data(sbi);
647
648         /* After POR, we can run background GC thread */
649         err = start_gc_thread(sbi);
650         if (err)
651                 goto fail;
652
653         err = f2fs_build_stats(sbi);
654         if (err)
655                 goto fail;
656
657         if (test_opt(sbi, DISCARD)) {
658                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
659                 if (!blk_queue_discard(q))
660                         f2fs_msg(sb, KERN_WARNING,
661                                         "mounting with \"discard\" option, but "
662                                         "the device does not support discard");
663         }
664
665         return 0;
666 fail:
667         stop_gc_thread(sbi);
668 free_root_inode:
669         dput(sb->s_root);
670         sb->s_root = NULL;
671 free_node_inode:
672         iput(sbi->node_inode);
673 free_nm:
674         destroy_node_manager(sbi);
675 free_sm:
676         destroy_segment_manager(sbi);
677 free_cp:
678         kfree(sbi->ckpt);
679 free_meta_inode:
680         make_bad_inode(sbi->meta_inode);
681         iput(sbi->meta_inode);
682 free_sb_buf:
683         brelse(raw_super_buf);
684 free_sbi:
685         kfree(sbi);
686         return err;
687 }
688
689 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
690                         const char *dev_name, void *data)
691 {
692         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
693 }
694
695 static struct file_system_type f2fs_fs_type = {
696         .owner          = THIS_MODULE,
697         .name           = "f2fs",
698         .mount          = f2fs_mount,
699         .kill_sb        = kill_block_super,
700         .fs_flags       = FS_REQUIRES_DEV,
701 };
702
703 static int __init init_inodecache(void)
704 {
705         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
706                         sizeof(struct f2fs_inode_info), NULL);
707         if (f2fs_inode_cachep == NULL)
708                 return -ENOMEM;
709         return 0;
710 }
711
712 static void destroy_inodecache(void)
713 {
714         /*
715          * Make sure all delayed rcu free inodes are flushed before we
716          * destroy cache.
717          */
718         rcu_barrier();
719         kmem_cache_destroy(f2fs_inode_cachep);
720 }
721
722 static int __init init_f2fs_fs(void)
723 {
724         int err;
725
726         err = init_inodecache();
727         if (err)
728                 goto fail;
729         err = create_node_manager_caches();
730         if (err)
731                 goto fail;
732         err = create_gc_caches();
733         if (err)
734                 goto fail;
735         err = create_checkpoint_caches();
736         if (err)
737                 goto fail;
738         err = register_filesystem(&f2fs_fs_type);
739         if (err)
740                 goto fail;
741         f2fs_create_root_stats();
742 fail:
743         return err;
744 }
745
746 static void __exit exit_f2fs_fs(void)
747 {
748         f2fs_destroy_root_stats();
749         unregister_filesystem(&f2fs_fs_type);
750         destroy_checkpoint_caches();
751         destroy_gc_caches();
752         destroy_node_manager_caches();
753         destroy_inodecache();
754 }
755
756 module_init(init_f2fs_fs)
757 module_exit(exit_f2fs_fs)
758
759 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
760 MODULE_DESCRIPTION("Flash Friendly File System");
761 MODULE_LICENSE("GPL");