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/f2fs_fs.h>
  25
  26 #include "f2fs.h"
  27 #include "node.h"
  28 #include "xattr.h"
  29
  30 static struct kmem_cache *f2fs_inode_cachep;
  31
  32 enum {
  33         Opt_gc_background_off,
  34         Opt_disable_roll_forward,
  35         Opt_discard,
  36         Opt_noheap,
  37         Opt_nouser_xattr,
  38         Opt_noacl,
  39         Opt_active_logs,
  40         Opt_disable_ext_identify,
  41         Opt_err,
  42 };
  43
  44 static match_table_t f2fs_tokens = {
  45         {Opt_gc_background_off, "background_gc_off"},
  46         {Opt_disable_roll_forward, "disable_roll_forward"},
  47         {Opt_discard, "discard"},
  48         {Opt_noheap, "no_heap"},
  49         {Opt_nouser_xattr, "nouser_xattr"},
  50         {Opt_noacl, "noacl"},
  51         {Opt_active_logs, "active_logs=%u"},
  52         {Opt_disable_ext_identify, "disable_ext_identify"},
  53         {Opt_err, NULL},
  54 };
  55
  56 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
  57 {
  58         struct va_format vaf;
  59         va_list args;
  60
  61         va_start(args, fmt);
  62         vaf.fmt = fmt;
  63         vaf.va = &args;
  64         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
  65         va_end(args);
  66 }
  67
  68 static void init_once(void *foo)
  69 {
  70         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
  71
  72         inode_init_once(&fi->vfs_inode);
  73 }
  74
  75 static struct inode *f2fs_alloc_inode(struct super_block *sb)
  76 {
  77         struct f2fs_inode_info *fi;
  78
  79         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
  80         if (!fi)
  81                 return NULL;
  82
  83         init_once((void *) fi);
  84
  85         /* Initilize f2fs-specific inode info */
  86         fi->vfs_inode.i_version = 1;
  87         atomic_set(&fi->dirty_dents, 0);
  88         fi->i_current_depth = 1;
  89         fi->i_advise = 0;
  90         rwlock_init(&fi->ext.ext_lock);
  91
  92         set_inode_flag(fi, FI_NEW_INODE);
  93
  94         return &fi->vfs_inode;
  95 }
  96
  97 static void f2fs_i_callback(struct rcu_head *head)
  98 {
  99         struct inode *inode = container_of(head, struct inode, i_rcu);
 100         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 101 }
 102
 103 static void f2fs_destroy_inode(struct inode *inode)
 104 {
 105         call_rcu(&inode->i_rcu, f2fs_i_callback);
 106 }
 107
 108 static void f2fs_put_super(struct super_block *sb)
 109 {
 110         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 111
 112         f2fs_destroy_stats(sbi);
 113         stop_gc_thread(sbi);
 114
 115         write_checkpoint(sbi, true);
 116
 117         iput(sbi->node_inode);
 118         iput(sbi->meta_inode);
 119
 120         /* destroy f2fs internal modules */
 121         destroy_node_manager(sbi);
 122         destroy_segment_manager(sbi);
 123
 124         kfree(sbi->ckpt);
 125
 126         sb->s_fs_info = NULL;
 127         brelse(sbi->raw_super_buf);
 128         kfree(sbi);
 129 }
 130
 131 int f2fs_sync_fs(struct super_block *sb, int sync)
 132 {
 133         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 134
 135         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 136                 return 0;
 137
 138         if (sync)
 139                 write_checkpoint(sbi, false);
 140         else
 141                 f2fs_balance_fs(sbi);
 142
 143         return 0;
 144 }
 145
 146 static int f2fs_freeze(struct super_block *sb)
 147 {
 148         int err;
 149
 150         if (sb->s_flags & MS_RDONLY)
 151                 return 0;
 152
 153         err = f2fs_sync_fs(sb, 1);
 154         return err;
 155 }
 156
 157 static int f2fs_unfreeze(struct super_block *sb)
 158 {
 159         return 0;
 160 }
 161
 162 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 163 {
 164         struct super_block *sb = dentry->d_sb;
 165         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 166         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 167         block_t total_count, user_block_count, start_count, ovp_count;
 168
 169         total_count = le64_to_cpu(sbi->raw_super->block_count);
 170         user_block_count = sbi->user_block_count;
 171         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 172         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 173         buf->f_type = F2FS_SUPER_MAGIC;
 174         buf->f_bsize = sbi->blocksize;
 175
 176         buf->f_blocks = total_count - start_count;
 177         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 178         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 179
 180         buf->f_files = sbi->total_node_count;
 181         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
 182
 183         buf->f_namelen = F2FS_MAX_NAME_LEN;
 184         buf->f_fsid.val[0] = (u32)id;
 185         buf->f_fsid.val[1] = (u32)(id >> 32);
 186
 187         return 0;
 188 }
 189
 190 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 191 {
 192         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 193
 194         if (test_opt(sbi, BG_GC))
 195                 seq_puts(seq, ",background_gc_on");
 196         else
 197                 seq_puts(seq, ",background_gc_off");
 198         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 199                 seq_puts(seq, ",disable_roll_forward");
 200         if (test_opt(sbi, DISCARD))
 201                 seq_puts(seq, ",discard");
 202         if (test_opt(sbi, NOHEAP))
 203                 seq_puts(seq, ",no_heap_alloc");
 204 #ifdef CONFIG_F2FS_FS_XATTR
 205         if (test_opt(sbi, XATTR_USER))
 206                 seq_puts(seq, ",user_xattr");
 207         else
 208                 seq_puts(seq, ",nouser_xattr");
 209 #endif
 210 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 211         if (test_opt(sbi, POSIX_ACL))
 212                 seq_puts(seq, ",acl");
 213         else
 214                 seq_puts(seq, ",noacl");
 215 #endif
 216         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 217                 seq_puts(seq, ",disable_ext_identify");
 218
 219         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 220
 221         return 0;
 222 }
 223
 224 static struct super_operations f2fs_sops = {
 225         .alloc_inode    = f2fs_alloc_inode,
 226         .destroy_inode  = f2fs_destroy_inode,
 227         .write_inode    = f2fs_write_inode,
 228         .show_options   = f2fs_show_options,
 229         .evict_inode    = f2fs_evict_inode,
 230         .put_super      = f2fs_put_super,
 231         .sync_fs        = f2fs_sync_fs,
 232         .freeze_fs      = f2fs_freeze,
 233         .unfreeze_fs    = f2fs_unfreeze,
 234         .statfs         = f2fs_statfs,
 235 };
 236
 237 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 238                 u64 ino, u32 generation)
 239 {
 240         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 241         struct inode *inode;
 242
 243         if (ino < F2FS_ROOT_INO(sbi))
 244                 return ERR_PTR(-ESTALE);
 245
 246         /*
 247          * f2fs_iget isn't quite right if the inode is currently unallocated!
 248          * However f2fs_iget currently does appropriate checks to handle stale
 249          * inodes so everything is OK.
 250          */
 251         inode = f2fs_iget(sb, ino);
 252         if (IS_ERR(inode))
 253                 return ERR_CAST(inode);
 254         if (generation && inode->i_generation != generation) {
 255                 /* we didn't find the right inode.. */
 256                 iput(inode);
 257                 return ERR_PTR(-ESTALE);
 258         }
 259         return inode;
 260 }
 261
 262 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 263                 int fh_len, int fh_type)
 264 {
 265         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 266                                     f2fs_nfs_get_inode);
 267 }
 268
 269 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 270                 int fh_len, int fh_type)
 271 {
 272         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 273                                     f2fs_nfs_get_inode);
 274 }
 275
 276 static const struct export_operations f2fs_export_ops = {
 277         .fh_to_dentry = f2fs_fh_to_dentry,
 278         .fh_to_parent = f2fs_fh_to_parent,
 279         .get_parent = f2fs_get_parent,
 280 };
 281
 282 static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
 283                                 char *options)
 284 {
 285         substring_t args[MAX_OPT_ARGS];
 286         char *p;
 287         int arg = 0;
 288
 289         if (!options)
 290                 return 0;
 291
 292         while ((p = strsep(&options, ",")) != NULL) {
 293                 int token;
 294                 if (!*p)
 295                         continue;
 296                 /*
 297                  * Initialize args struct so we know whether arg was
 298                  * found; some options take optional arguments.
 299                  */
 300                 args[0].to = args[0].from = NULL;
 301                 token = match_token(p, f2fs_tokens, args);
 302
 303                 switch (token) {
 304                 case Opt_gc_background_off:
 305                         clear_opt(sbi, BG_GC);
 306                         break;
 307                 case Opt_disable_roll_forward:
 308                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 309                         break;
 310                 case Opt_discard:
 311                         set_opt(sbi, DISCARD);
 312                         break;
 313                 case Opt_noheap:
 314                         set_opt(sbi, NOHEAP);
 315                         break;
 316 #ifdef CONFIG_F2FS_FS_XATTR
 317                 case Opt_nouser_xattr:
 318                         clear_opt(sbi, XATTR_USER);
 319                         break;
 320 #else
 321                 case Opt_nouser_xattr:
 322                         f2fs_msg(sb, KERN_INFO,
 323                                 "nouser_xattr options not supported");
 324                         break;
 325 #endif
 326 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 327                 case Opt_noacl:
 328                         clear_opt(sbi, POSIX_ACL);
 329                         break;
 330 #else
 331                 case Opt_noacl:
 332                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 333                         break;
 334 #endif
 335                 case Opt_active_logs:
 336                         if (args->from && match_int(args, &arg))
 337                                 return -EINVAL;
 338                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 339                                 return -EINVAL;
 340                         sbi->active_logs = arg;
 341                         break;
 342                 case Opt_disable_ext_identify:
 343                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 344                         break;
 345                 default:
 346                         f2fs_msg(sb, KERN_ERR,
 347                                 "Unrecognized mount option \"%s\" or missing value",
 348                                 p);
 349                         return -EINVAL;
 350                 }
 351         }
 352         return 0;
 353 }
 354
 355 static loff_t max_file_size(unsigned bits)
 356 {
 357         loff_t result = ADDRS_PER_INODE;
 358         loff_t leaf_count = ADDRS_PER_BLOCK;
 359
 360         /* two direct node blocks */
 361         result += (leaf_count * 2);
 362
 363         /* two indirect node blocks */
 364         leaf_count *= NIDS_PER_BLOCK;
 365         result += (leaf_count * 2);
 366
 367         /* one double indirect node block */
 368         leaf_count *= NIDS_PER_BLOCK;
 369         result += leaf_count;
 370
 371         result <<= bits;
 372         return result;
 373 }
 374
 375 static int sanity_check_raw_super(struct super_block *sb,
 376                         struct f2fs_super_block *raw_super)
 377 {
 378         unsigned int blocksize;
 379
 380         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 381                 f2fs_msg(sb, KERN_INFO,
 382                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 383                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 384                 return 1;
 385         }
 386
 387         /* Currently, support only 4KB page cache size */
 388         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 389                 f2fs_msg(sb, KERN_INFO,
 390                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 391                         PAGE_CACHE_SIZE);
 392                 return 1;
 393         }
 394
 395         /* Currently, support only 4KB block size */
 396         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 397         if (blocksize != F2FS_BLKSIZE) {
 398                 f2fs_msg(sb, KERN_INFO,
 399                         "Invalid blocksize (%u), supports only 4KB\n",
 400                         blocksize);
 401                 return 1;
 402         }
 403
 404         if (le32_to_cpu(raw_super->log_sectorsize) !=
 405                                         F2FS_LOG_SECTOR_SIZE) {
 406                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 407                 return 1;
 408         }
 409         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 410                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 411                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 412                 return 1;
 413         }
 414         return 0;
 415 }
 416
 417 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 418 {
 419         unsigned int total, fsmeta;
 420         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 421         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 422
 423         total = le32_to_cpu(raw_super->segment_count);
 424         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 425         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 426         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 427         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 428         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 429
 430         if (fsmeta >= total)
 431                 return 1;
 432
 433         if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
 434                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 435                 return 1;
 436         }
 437         return 0;
 438 }
 439
 440 static void init_sb_info(struct f2fs_sb_info *sbi)
 441 {
 442         struct f2fs_super_block *raw_super = sbi->raw_super;
 443         int i;
 444
 445         sbi->log_sectors_per_block =
 446                 le32_to_cpu(raw_super->log_sectors_per_block);
 447         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 448         sbi->blocksize = 1 << sbi->log_blocksize;
 449         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 450         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 451         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 452         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 453         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 454         sbi->total_node_count =
 455                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 456                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 457         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 458         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 459         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 460
 461         for (i = 0; i < NR_COUNT_TYPE; i++)
 462                 atomic_set(&sbi->nr_pages[i], 0);
 463 }
 464
 465 static int validate_superblock(struct super_block *sb,
 466                 struct f2fs_super_block **raw_super,
 467                 struct buffer_head **raw_super_buf, sector_t block)
 468 {
 469         const char *super = (block == 0 ? "first" : "second");
 470
 471         /* read f2fs raw super block */
 472         *raw_super_buf = sb_bread(sb, block);
 473         if (!*raw_super_buf) {
 474                 f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
 475                                 super);
 476                 return 1;
 477         }
 478
 479         *raw_super = (struct f2fs_super_block *)
 480                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 481
 482         /* sanity checking of raw super */
 483         if (!sanity_check_raw_super(sb, *raw_super))
 484                 return 0;
 485
 486         f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
 487                                 "in %s superblock", super);
 488         return 1;
 489 }
 490
 491 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 492 {
 493         struct f2fs_sb_info *sbi;
 494         struct f2fs_super_block *raw_super;
 495         struct buffer_head *raw_super_buf;
 496         struct inode *root;
 497         long err = -EINVAL;
 498         int i;
 499
 500         /* allocate memory for f2fs-specific super block info */
 501         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 502         if (!sbi)
 503                 return -ENOMEM;
 504
 505         /* set a block size */
 506         if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
 507                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 508                 goto free_sbi;
 509         }
 510
 511         if (validate_superblock(sb, &raw_super, &raw_super_buf, 0)) {
 512                 brelse(raw_super_buf);
 513                 if (validate_superblock(sb, &raw_super, &raw_super_buf, 1))
 514                         goto free_sb_buf;
 515         }
 516         /* init some FS parameters */
 517         sbi->active_logs = NR_CURSEG_TYPE;
 518
 519         set_opt(sbi, BG_GC);
 520
 521 #ifdef CONFIG_F2FS_FS_XATTR
 522         set_opt(sbi, XATTR_USER);
 523 #endif
 524 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 525         set_opt(sbi, POSIX_ACL);
 526 #endif
 527         /* parse mount options */
 528         if (parse_options(sb, sbi, (char *)data))
 529                 goto free_sb_buf;
 530
 531         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 532         sb->s_max_links = F2FS_LINK_MAX;
 533         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 534
 535         sb->s_op = &f2fs_sops;
 536         sb->s_xattr = f2fs_xattr_handlers;
 537         sb->s_export_op = &f2fs_export_ops;
 538         sb->s_magic = F2FS_SUPER_MAGIC;
 539         sb->s_fs_info = sbi;
 540         sb->s_time_gran = 1;
 541         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 542                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 543         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 544
 545         /* init f2fs-specific super block info */
 546         sbi->sb = sb;
 547         sbi->raw_super = raw_super;
 548         sbi->raw_super_buf = raw_super_buf;
 549         mutex_init(&sbi->gc_mutex);
 550         mutex_init(&sbi->write_inode);
 551         mutex_init(&sbi->writepages);
 552         mutex_init(&sbi->cp_mutex);
 553         for (i = 0; i < NR_LOCK_TYPE; i++)
 554                 mutex_init(&sbi->fs_lock[i]);
 555         sbi->por_doing = 0;
 556         spin_lock_init(&sbi->stat_lock);
 557         init_rwsem(&sbi->bio_sem);
 558         init_sb_info(sbi);
 559
 560         /* get an inode for meta space */
 561         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 562         if (IS_ERR(sbi->meta_inode)) {
 563                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 564                 err = PTR_ERR(sbi->meta_inode);
 565                 goto free_sb_buf;
 566         }
 567
 568         err = get_valid_checkpoint(sbi);
 569         if (err) {
 570                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 571                 goto free_meta_inode;
 572         }
 573
 574         /* sanity checking of checkpoint */
 575         err = -EINVAL;
 576         if (sanity_check_ckpt(sbi)) {
 577                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 578                 goto free_cp;
 579         }
 580
 581         sbi->total_valid_node_count =
 582                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 583         sbi->total_valid_inode_count =
 584                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 585         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 586         sbi->total_valid_block_count =
 587                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 588         sbi->last_valid_block_count = sbi->total_valid_block_count;
 589         sbi->alloc_valid_block_count = 0;
 590         INIT_LIST_HEAD(&sbi->dir_inode_list);
 591         spin_lock_init(&sbi->dir_inode_lock);
 592
 593         init_orphan_info(sbi);
 594
 595         /* setup f2fs internal modules */
 596         err = build_segment_manager(sbi);
 597         if (err) {
 598                 f2fs_msg(sb, KERN_ERR,
 599                         "Failed to initialize F2FS segment manager");
 600                 goto free_sm;
 601         }
 602         err = build_node_manager(sbi);
 603         if (err) {
 604                 f2fs_msg(sb, KERN_ERR,
 605                         "Failed to initialize F2FS node manager");
 606                 goto free_nm;
 607         }
 608
 609         build_gc_manager(sbi);
 610
 611         /* get an inode for node space */
 612         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
 613         if (IS_ERR(sbi->node_inode)) {
 614                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
 615                 err = PTR_ERR(sbi->node_inode);
 616                 goto free_nm;
 617         }
 618
 619         /* if there are nt orphan nodes free them */
 620         err = -EINVAL;
 621         if (recover_orphan_inodes(sbi))
 622                 goto free_node_inode;
 623
 624         /* read root inode and dentry */
 625         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
 626         if (IS_ERR(root)) {
 627                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
 628                 err = PTR_ERR(root);
 629                 goto free_node_inode;
 630         }
 631         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
 632                 goto free_root_inode;
 633
 634         sb->s_root = d_make_root(root); /* allocate root dentry */
 635         if (!sb->s_root) {
 636                 err = -ENOMEM;
 637                 goto free_root_inode;
 638         }
 639
 640         /* recover fsynced data */
 641         if (!test_opt(sbi, DISABLE_ROLL_FORWARD))
 642                 recover_fsync_data(sbi);
 643
 644         /* After POR, we can run background GC thread */
 645         err = start_gc_thread(sbi);
 646         if (err)
 647                 goto fail;
 648
 649         err = f2fs_build_stats(sbi);
 650         if (err)
 651                 goto fail;
 652
 653         return 0;
 654 fail:
 655         stop_gc_thread(sbi);
 656 free_root_inode:
 657         dput(sb->s_root);
 658         sb->s_root = NULL;
 659 free_node_inode:
 660         iput(sbi->node_inode);
 661 free_nm:
 662         destroy_node_manager(sbi);
 663 free_sm:
 664         destroy_segment_manager(sbi);
 665 free_cp:
 666         kfree(sbi->ckpt);
 667 free_meta_inode:
 668         make_bad_inode(sbi->meta_inode);
 669         iput(sbi->meta_inode);
 670 free_sb_buf:
 671         brelse(raw_super_buf);
 672 free_sbi:
 673         kfree(sbi);
 674         return err;
 675 }
 676
 677 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
 678                         const char *dev_name, void *data)
 679 {
 680         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
 681 }
 682
 683 static struct file_system_type f2fs_fs_type = {
 684         .owner          = THIS_MODULE,
 685         .name           = "f2fs",
 686         .mount          = f2fs_mount,
 687         .kill_sb        = kill_block_super,
 688         .fs_flags       = FS_REQUIRES_DEV,
 689 };
 690 MODULE_ALIAS_FS("f2fs");
 691
 692 static int __init init_inodecache(void)
 693 {
 694         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
 695                         sizeof(struct f2fs_inode_info), NULL);
 696         if (f2fs_inode_cachep == NULL)
 697                 return -ENOMEM;
 698         return 0;
 699 }
 700
 701 static void destroy_inodecache(void)
 702 {
 703         /*
 704          * Make sure all delayed rcu free inodes are flushed before we
 705          * destroy cache.
 706          */
 707         rcu_barrier();
 708         kmem_cache_destroy(f2fs_inode_cachep);
 709 }
 710
 711 static int __init init_f2fs_fs(void)
 712 {
 713         int err;
 714
 715         err = init_inodecache();
 716         if (err)
 717                 goto fail;
 718         err = create_node_manager_caches();
 719         if (err)
 720                 goto fail;
 721         err = create_gc_caches();
 722         if (err)
 723                 goto fail;
 724         err = create_checkpoint_caches();
 725         if (err)
 726                 goto fail;
 727         err = register_filesystem(&f2fs_fs_type);
 728         if (err)
 729                 goto fail;
 730         f2fs_create_root_stats();
 731 fail:
 732         return err;
 733 }
 734
 735 static void __exit exit_f2fs_fs(void)
 736 {
 737         f2fs_destroy_root_stats();
 738         unregister_filesystem(&f2fs_fs_type);
 739         destroy_checkpoint_caches();
 740         destroy_gc_caches();
 741         destroy_node_manager_caches();
 742         destroy_inodecache();
 743 }
 744
 745 module_init(init_f2fs_fs)
 746 module_exit(exit_f2fs_fs)
 747
 748 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
 749 MODULE_DESCRIPTION("Flash Friendly File System");
 750 MODULE_LICENSE("GPL");