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 "segment.h"
  30 #include "xattr.h"
  31
  32 #define CREATE_TRACE_POINTS
  33 #include <trace/events/f2fs.h>
  34
  35 static struct kmem_cache *f2fs_inode_cachep;
  36
  37 enum {
  38         Opt_gc_background_off,
  39         Opt_disable_roll_forward,
  40         Opt_discard,
  41         Opt_noheap,
  42         Opt_nouser_xattr,
  43         Opt_noacl,
  44         Opt_active_logs,
  45         Opt_disable_ext_identify,
  46         Opt_err,
  47 };
  48
  49 static match_table_t f2fs_tokens = {
  50         {Opt_gc_background_off, "background_gc_off"},
  51         {Opt_disable_roll_forward, "disable_roll_forward"},
  52         {Opt_discard, "discard"},
  53         {Opt_noheap, "no_heap"},
  54         {Opt_nouser_xattr, "nouser_xattr"},
  55         {Opt_noacl, "noacl"},
  56         {Opt_active_logs, "active_logs=%u"},
  57         {Opt_disable_ext_identify, "disable_ext_identify"},
  58         {Opt_err, NULL},
  59 };
  60
  61 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
  62 {
  63         struct va_format vaf;
  64         va_list args;
  65
  66         va_start(args, fmt);
  67         vaf.fmt = fmt;
  68         vaf.va = &args;
  69         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
  70         va_end(args);
  71 }
  72
  73 static void init_once(void *foo)
  74 {
  75         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
  76
  77         inode_init_once(&fi->vfs_inode);
  78 }
  79
  80 static struct inode *f2fs_alloc_inode(struct super_block *sb)
  81 {
  82         struct f2fs_inode_info *fi;
  83
  84         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
  85         if (!fi)
  86                 return NULL;
  87
  88         init_once((void *) fi);
  89
  90         /* Initialize f2fs-specific inode info */
  91         fi->vfs_inode.i_version = 1;
  92         atomic_set(&fi->dirty_dents, 0);
  93         fi->i_current_depth = 1;
  94         fi->i_advise = 0;
  95         rwlock_init(&fi->ext.ext_lock);
  96
  97         set_inode_flag(fi, FI_NEW_INODE);
  98
  99         return &fi->vfs_inode;
 100 }
 101
 102 static void f2fs_i_callback(struct rcu_head *head)
 103 {
 104         struct inode *inode = container_of(head, struct inode, i_rcu);
 105         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 106 }
 107
 108 static void f2fs_destroy_inode(struct inode *inode)
 109 {
 110         call_rcu(&inode->i_rcu, f2fs_i_callback);
 111 }
 112
 113 static void f2fs_put_super(struct super_block *sb)
 114 {
 115         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 116
 117         f2fs_destroy_stats(sbi);
 118         stop_gc_thread(sbi);
 119
 120         write_checkpoint(sbi, true);
 121
 122         iput(sbi->node_inode);
 123         iput(sbi->meta_inode);
 124
 125         /* destroy f2fs internal modules */
 126         destroy_node_manager(sbi);
 127         destroy_segment_manager(sbi);
 128
 129         kfree(sbi->ckpt);
 130
 131         sb->s_fs_info = NULL;
 132         brelse(sbi->raw_super_buf);
 133         kfree(sbi);
 134 }
 135
 136 int f2fs_sync_fs(struct super_block *sb, int sync)
 137 {
 138         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 139
 140         trace_f2fs_sync_fs(sb, sync);
 141
 142         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 143                 return 0;
 144
 145         if (sync) {
 146                 mutex_lock(&sbi->gc_mutex);
 147                 write_checkpoint(sbi, false);
 148                 mutex_unlock(&sbi->gc_mutex);
 149         } else {
 150                 f2fs_balance_fs(sbi);
 151         }
 152
 153         return 0;
 154 }
 155
 156 static int f2fs_freeze(struct super_block *sb)
 157 {
 158         int err;
 159
 160         if (sb->s_flags & MS_RDONLY)
 161                 return 0;
 162
 163         err = f2fs_sync_fs(sb, 1);
 164         return err;
 165 }
 166
 167 static int f2fs_unfreeze(struct super_block *sb)
 168 {
 169         return 0;
 170 }
 171
 172 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 173 {
 174         struct super_block *sb = dentry->d_sb;
 175         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 176         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 177         block_t total_count, user_block_count, start_count, ovp_count;
 178
 179         total_count = le64_to_cpu(sbi->raw_super->block_count);
 180         user_block_count = sbi->user_block_count;
 181         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 182         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 183         buf->f_type = F2FS_SUPER_MAGIC;
 184         buf->f_bsize = sbi->blocksize;
 185
 186         buf->f_blocks = total_count - start_count;
 187         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 188         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 189
 190         buf->f_files = sbi->total_node_count;
 191         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
 192
 193         buf->f_namelen = F2FS_NAME_LEN;
 194         buf->f_fsid.val[0] = (u32)id;
 195         buf->f_fsid.val[1] = (u32)(id >> 32);
 196
 197         return 0;
 198 }
 199
 200 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 201 {
 202         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 203
 204         if (test_opt(sbi, BG_GC))
 205                 seq_puts(seq, ",background_gc_on");
 206         else
 207                 seq_puts(seq, ",background_gc_off");
 208         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 209                 seq_puts(seq, ",disable_roll_forward");
 210         if (test_opt(sbi, DISCARD))
 211                 seq_puts(seq, ",discard");
 212         if (test_opt(sbi, NOHEAP))
 213                 seq_puts(seq, ",no_heap_alloc");
 214 #ifdef CONFIG_F2FS_FS_XATTR
 215         if (test_opt(sbi, XATTR_USER))
 216                 seq_puts(seq, ",user_xattr");
 217         else
 218                 seq_puts(seq, ",nouser_xattr");
 219 #endif
 220 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 221         if (test_opt(sbi, POSIX_ACL))
 222                 seq_puts(seq, ",acl");
 223         else
 224                 seq_puts(seq, ",noacl");
 225 #endif
 226         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 227                 seq_puts(seq, ",disable_ext_identify");
 228
 229         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 230
 231         return 0;
 232 }
 233
 234 static struct super_operations f2fs_sops = {
 235         .alloc_inode    = f2fs_alloc_inode,
 236         .destroy_inode  = f2fs_destroy_inode,
 237         .write_inode    = f2fs_write_inode,
 238         .show_options   = f2fs_show_options,
 239         .evict_inode    = f2fs_evict_inode,
 240         .put_super      = f2fs_put_super,
 241         .sync_fs        = f2fs_sync_fs,
 242         .freeze_fs      = f2fs_freeze,
 243         .unfreeze_fs    = f2fs_unfreeze,
 244         .statfs         = f2fs_statfs,
 245 };
 246
 247 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 248                 u64 ino, u32 generation)
 249 {
 250         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 251         struct inode *inode;
 252
 253         if (ino < F2FS_ROOT_INO(sbi))
 254                 return ERR_PTR(-ESTALE);
 255
 256         /*
 257          * f2fs_iget isn't quite right if the inode is currently unallocated!
 258          * However f2fs_iget currently does appropriate checks to handle stale
 259          * inodes so everything is OK.
 260          */
 261         inode = f2fs_iget(sb, ino);
 262         if (IS_ERR(inode))
 263                 return ERR_CAST(inode);
 264         if (generation && inode->i_generation != generation) {
 265                 /* we didn't find the right inode.. */
 266                 iput(inode);
 267                 return ERR_PTR(-ESTALE);
 268         }
 269         return inode;
 270 }
 271
 272 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 273                 int fh_len, int fh_type)
 274 {
 275         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 276                                     f2fs_nfs_get_inode);
 277 }
 278
 279 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 280                 int fh_len, int fh_type)
 281 {
 282         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 283                                     f2fs_nfs_get_inode);
 284 }
 285
 286 static const struct export_operations f2fs_export_ops = {
 287         .fh_to_dentry = f2fs_fh_to_dentry,
 288         .fh_to_parent = f2fs_fh_to_parent,
 289         .get_parent = f2fs_get_parent,
 290 };
 291
 292 static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
 293                                 char *options)
 294 {
 295         substring_t args[MAX_OPT_ARGS];
 296         char *p;
 297         int arg = 0;
 298
 299         if (!options)
 300                 return 0;
 301
 302         while ((p = strsep(&options, ",")) != NULL) {
 303                 int token;
 304                 if (!*p)
 305                         continue;
 306                 /*
 307                  * Initialize args struct so we know whether arg was
 308                  * found; some options take optional arguments.
 309                  */
 310                 args[0].to = args[0].from = NULL;
 311                 token = match_token(p, f2fs_tokens, args);
 312
 313                 switch (token) {
 314                 case Opt_gc_background_off:
 315                         clear_opt(sbi, BG_GC);
 316                         break;
 317                 case Opt_disable_roll_forward:
 318                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 319                         break;
 320                 case Opt_discard:
 321                         set_opt(sbi, DISCARD);
 322                         break;
 323                 case Opt_noheap:
 324                         set_opt(sbi, NOHEAP);
 325                         break;
 326 #ifdef CONFIG_F2FS_FS_XATTR
 327                 case Opt_nouser_xattr:
 328                         clear_opt(sbi, XATTR_USER);
 329                         break;
 330 #else
 331                 case Opt_nouser_xattr:
 332                         f2fs_msg(sb, KERN_INFO,
 333                                 "nouser_xattr options not supported");
 334                         break;
 335 #endif
 336 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 337                 case Opt_noacl:
 338                         clear_opt(sbi, POSIX_ACL);
 339                         break;
 340 #else
 341                 case Opt_noacl:
 342                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 343                         break;
 344 #endif
 345                 case Opt_active_logs:
 346                         if (args->from && match_int(args, &arg))
 347                                 return -EINVAL;
 348                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 349                                 return -EINVAL;
 350                         sbi->active_logs = arg;
 351                         break;
 352                 case Opt_disable_ext_identify:
 353                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 354                         break;
 355                 default:
 356                         f2fs_msg(sb, KERN_ERR,
 357                                 "Unrecognized mount option \"%s\" or missing value",
 358                                 p);
 359                         return -EINVAL;
 360                 }
 361         }
 362         return 0;
 363 }
 364
 365 static loff_t max_file_size(unsigned bits)
 366 {
 367         loff_t result = ADDRS_PER_INODE;
 368         loff_t leaf_count = ADDRS_PER_BLOCK;
 369
 370         /* two direct node blocks */
 371         result += (leaf_count * 2);
 372
 373         /* two indirect node blocks */
 374         leaf_count *= NIDS_PER_BLOCK;
 375         result += (leaf_count * 2);
 376
 377         /* one double indirect node block */
 378         leaf_count *= NIDS_PER_BLOCK;
 379         result += leaf_count;
 380
 381         result <<= bits;
 382         return result;
 383 }
 384
 385 static int sanity_check_raw_super(struct super_block *sb,
 386                         struct f2fs_super_block *raw_super)
 387 {
 388         unsigned int blocksize;
 389
 390         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 391                 f2fs_msg(sb, KERN_INFO,
 392                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 393                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 394                 return 1;
 395         }
 396
 397         /* Currently, support only 4KB page cache size */
 398         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 399                 f2fs_msg(sb, KERN_INFO,
 400                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 401                         PAGE_CACHE_SIZE);
 402                 return 1;
 403         }
 404
 405         /* Currently, support only 4KB block size */
 406         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 407         if (blocksize != F2FS_BLKSIZE) {
 408                 f2fs_msg(sb, KERN_INFO,
 409                         "Invalid blocksize (%u), supports only 4KB\n",
 410                         blocksize);
 411                 return 1;
 412         }
 413
 414         if (le32_to_cpu(raw_super->log_sectorsize) !=
 415                                         F2FS_LOG_SECTOR_SIZE) {
 416                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 417                 return 1;
 418         }
 419         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 420                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 421                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 422                 return 1;
 423         }
 424         return 0;
 425 }
 426
 427 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 428 {
 429         unsigned int total, fsmeta;
 430         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 431         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 432
 433         total = le32_to_cpu(raw_super->segment_count);
 434         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 435         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 436         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 437         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 438         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 439
 440         if (fsmeta >= total)
 441                 return 1;
 442
 443         if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
 444                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 445                 return 1;
 446         }
 447         return 0;
 448 }
 449
 450 static void init_sb_info(struct f2fs_sb_info *sbi)
 451 {
 452         struct f2fs_super_block *raw_super = sbi->raw_super;
 453         int i;
 454
 455         sbi->log_sectors_per_block =
 456                 le32_to_cpu(raw_super->log_sectors_per_block);
 457         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 458         sbi->blocksize = 1 << sbi->log_blocksize;
 459         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 460         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 461         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 462         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 463         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 464         sbi->total_node_count =
 465                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 466                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 467         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 468         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 469         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 470         sbi->cur_victim_sec = NULL_SECNO;
 471
 472         for (i = 0; i < NR_COUNT_TYPE; i++)
 473                 atomic_set(&sbi->nr_pages[i], 0);
 474 }
 475
 476 static int validate_superblock(struct super_block *sb,
 477                 struct f2fs_super_block **raw_super,
 478                 struct buffer_head **raw_super_buf, sector_t block)
 479 {
 480         const char *super = (block == 0 ? "first" : "second");
 481
 482         /* read f2fs raw super block */
 483         *raw_super_buf = sb_bread(sb, block);
 484         if (!*raw_super_buf) {
 485                 f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
 486                                 super);
 487                 return -EIO;
 488         }
 489
 490         *raw_super = (struct f2fs_super_block *)
 491                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 492
 493         /* sanity checking of raw super */
 494         if (!sanity_check_raw_super(sb, *raw_super))
 495                 return 0;
 496
 497         f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
 498                                 "in %s superblock", super);
 499         return -EINVAL;
 500 }
 501
 502 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 503 {
 504         struct f2fs_sb_info *sbi;
 505         struct f2fs_super_block *raw_super;
 506         struct buffer_head *raw_super_buf;
 507         struct inode *root;
 508         long err = -EINVAL;
 509         int i;
 510
 511         /* allocate memory for f2fs-specific super block info */
 512         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 513         if (!sbi)
 514                 return -ENOMEM;
 515
 516         /* set a block size */
 517         if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
 518                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 519                 goto free_sbi;
 520         }
 521
 522         err = validate_superblock(sb, &raw_super, &raw_super_buf, 0);
 523         if (err) {
 524                 brelse(raw_super_buf);
 525                 /* check secondary superblock when primary failed */
 526                 err = validate_superblock(sb, &raw_super, &raw_super_buf, 1);
 527                 if (err)
 528                         goto free_sb_buf;
 529         }
 530         /* init some FS parameters */
 531         sbi->active_logs = NR_CURSEG_TYPE;
 532
 533         set_opt(sbi, BG_GC);
 534
 535 #ifdef CONFIG_F2FS_FS_XATTR
 536         set_opt(sbi, XATTR_USER);
 537 #endif
 538 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 539         set_opt(sbi, POSIX_ACL);
 540 #endif
 541         /* parse mount options */
 542         err = parse_options(sb, sbi, (char *)data);
 543         if (err)
 544                 goto free_sb_buf;
 545
 546         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 547         sb->s_max_links = F2FS_LINK_MAX;
 548         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 549
 550         sb->s_op = &f2fs_sops;
 551         sb->s_xattr = f2fs_xattr_handlers;
 552         sb->s_export_op = &f2fs_export_ops;
 553         sb->s_magic = F2FS_SUPER_MAGIC;
 554         sb->s_fs_info = sbi;
 555         sb->s_time_gran = 1;
 556         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 557                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 558         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 559
 560         /* init f2fs-specific super block info */
 561         sbi->sb = sb;
 562         sbi->raw_super = raw_super;
 563         sbi->raw_super_buf = raw_super_buf;
 564         mutex_init(&sbi->gc_mutex);
 565         mutex_init(&sbi->writepages);
 566         mutex_init(&sbi->cp_mutex);
 567         for (i = 0; i < NR_GLOBAL_LOCKS; i++)
 568                 mutex_init(&sbi->fs_lock[i]);
 569         mutex_init(&sbi->node_write);
 570         sbi->por_doing = 0;
 571         spin_lock_init(&sbi->stat_lock);
 572         init_rwsem(&sbi->bio_sem);
 573         init_sb_info(sbi);
 574
 575         /* get an inode for meta space */
 576         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 577         if (IS_ERR(sbi->meta_inode)) {
 578                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 579                 err = PTR_ERR(sbi->meta_inode);
 580                 goto free_sb_buf;
 581         }
 582
 583         err = get_valid_checkpoint(sbi);
 584         if (err) {
 585                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 586                 goto free_meta_inode;
 587         }
 588
 589         /* sanity checking of checkpoint */
 590         err = -EINVAL;
 591         if (sanity_check_ckpt(sbi)) {
 592                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 593                 goto free_cp;
 594         }
 595
 596         sbi->total_valid_node_count =
 597                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 598         sbi->total_valid_inode_count =
 599                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 600         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 601         sbi->total_valid_block_count =
 602                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 603         sbi->last_valid_block_count = sbi->total_valid_block_count;
 604         sbi->alloc_valid_block_count = 0;
 605         INIT_LIST_HEAD(&sbi->dir_inode_list);
 606         spin_lock_init(&sbi->dir_inode_lock);
 607
 608         init_orphan_info(sbi);
 609
 610         /* setup f2fs internal modules */
 611         err = build_segment_manager(sbi);
 612         if (err) {
 613                 f2fs_msg(sb, KERN_ERR,
 614                         "Failed to initialize F2FS segment manager");
 615                 goto free_sm;
 616         }
 617         err = build_node_manager(sbi);
 618         if (err) {
 619                 f2fs_msg(sb, KERN_ERR,
 620                         "Failed to initialize F2FS node manager");
 621                 goto free_nm;
 622         }
 623
 624         build_gc_manager(sbi);
 625
 626         /* get an inode for node space */
 627         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
 628         if (IS_ERR(sbi->node_inode)) {
 629                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
 630                 err = PTR_ERR(sbi->node_inode);
 631                 goto free_nm;
 632         }
 633
 634         /* if there are nt orphan nodes free them */
 635         err = -EINVAL;
 636         if (recover_orphan_inodes(sbi))
 637                 goto free_node_inode;
 638
 639         /* read root inode and dentry */
 640         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
 641         if (IS_ERR(root)) {
 642                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
 643                 err = PTR_ERR(root);
 644                 goto free_node_inode;
 645         }
 646         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
 647                 goto free_root_inode;
 648
 649         sb->s_root = d_make_root(root); /* allocate root dentry */
 650         if (!sb->s_root) {
 651                 err = -ENOMEM;
 652                 goto free_root_inode;
 653         }
 654
 655         /* recover fsynced data */
 656         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
 657                 err = recover_fsync_data(sbi);
 658                 if (err) {
 659                         f2fs_msg(sb, KERN_ERR, "Failed to recover fsync data");
 660                         goto free_root_inode;
 661                 }
 662         }
 663
 664         /* After POR, we can run background GC thread */
 665         err = start_gc_thread(sbi);
 666         if (err)
 667                 goto fail;
 668
 669         err = f2fs_build_stats(sbi);
 670         if (err)
 671                 goto fail;
 672
 673         if (test_opt(sbi, DISCARD)) {
 674                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 675                 if (!blk_queue_discard(q))
 676                         f2fs_msg(sb, KERN_WARNING,
 677                                         "mounting with \"discard\" option, but "
 678                                         "the device does not support discard");
 679         }
 680
 681         return 0;
 682 fail:
 683         stop_gc_thread(sbi);
 684 free_root_inode:
 685         dput(sb->s_root);
 686         sb->s_root = NULL;
 687 free_node_inode:
 688         iput(sbi->node_inode);
 689 free_nm:
 690         destroy_node_manager(sbi);
 691 free_sm:
 692         destroy_segment_manager(sbi);
 693 free_cp:
 694         kfree(sbi->ckpt);
 695 free_meta_inode:
 696         make_bad_inode(sbi->meta_inode);
 697         iput(sbi->meta_inode);
 698 free_sb_buf:
 699         brelse(raw_super_buf);
 700 free_sbi:
 701         kfree(sbi);
 702         return err;
 703 }
 704
 705 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
 706                         const char *dev_name, void *data)
 707 {
 708         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
 709 }
 710
 711 static struct file_system_type f2fs_fs_type = {
 712         .owner          = THIS_MODULE,
 713         .name           = "f2fs",
 714         .mount          = f2fs_mount,
 715         .kill_sb        = kill_block_super,
 716         .fs_flags       = FS_REQUIRES_DEV,
 717 };
 718
 719 static int __init init_inodecache(void)
 720 {
 721         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
 722                         sizeof(struct f2fs_inode_info), NULL);
 723         if (f2fs_inode_cachep == NULL)
 724                 return -ENOMEM;
 725         return 0;
 726 }
 727
 728 static void destroy_inodecache(void)
 729 {
 730         /*
 731          * Make sure all delayed rcu free inodes are flushed before we
 732          * destroy cache.
 733          */
 734         rcu_barrier();
 735         kmem_cache_destroy(f2fs_inode_cachep);
 736 }
 737
 738 static int __init init_f2fs_fs(void)
 739 {
 740         int err;
 741
 742         err = init_inodecache();
 743         if (err)
 744                 goto fail;
 745         err = create_node_manager_caches();
 746         if (err)
 747                 goto fail;
 748         err = create_gc_caches();
 749         if (err)
 750                 goto fail;
 751         err = create_checkpoint_caches();
 752         if (err)
 753                 goto fail;
 754         err = register_filesystem(&f2fs_fs_type);
 755         if (err)
 756                 goto fail;
 757         f2fs_create_root_stats();
 758 fail:
 759         return err;
 760 }
 761
 762 static void __exit exit_f2fs_fs(void)
 763 {
 764         f2fs_destroy_root_stats();
 765         unregister_filesystem(&f2fs_fs_type);
 766         destroy_checkpoint_caches();
 767         destroy_gc_caches();
 768         destroy_node_manager_caches();
 769         destroy_inodecache();
 770 }
 771
 772 module_init(init_f2fs_fs)
 773 module_exit(exit_f2fs_fs)
 774
 775 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
 776 MODULE_DESCRIPTION("Flash Friendly File System");
 777 MODULE_LICENSE("GPL");