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 1;
 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 1;
 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         if (validate_superblock(sb, &raw_super, &raw_super_buf, 0)) {
 513                 brelse(raw_super_buf);
 514                 if (validate_superblock(sb, &raw_super, &raw_super_buf, 1))
 515                         goto free_sb_buf;
 516         }
 517         /* init some FS parameters */
 518         sbi->active_logs = NR_CURSEG_TYPE;
 519
 520         set_opt(sbi, BG_GC);
 521
 522 #ifdef CONFIG_F2FS_FS_XATTR
 523         set_opt(sbi, XATTR_USER);
 524 #endif
 525 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 526         set_opt(sbi, POSIX_ACL);
 527 #endif
 528         /* parse mount options */
 529         if (parse_options(sb, sbi, (char *)data))
 530                 goto free_sb_buf;
 531
 532         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 533         sb->s_max_links = F2FS_LINK_MAX;
 534         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 535
 536         sb->s_op = &f2fs_sops;
 537         sb->s_xattr = f2fs_xattr_handlers;
 538         sb->s_export_op = &f2fs_export_ops;
 539         sb->s_magic = F2FS_SUPER_MAGIC;
 540         sb->s_fs_info = sbi;
 541         sb->s_time_gran = 1;
 542         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 543                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 544         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 545
 546         /* init f2fs-specific super block info */
 547         sbi->sb = sb;
 548         sbi->raw_super = raw_super;
 549         sbi->raw_super_buf = raw_super_buf;
 550         mutex_init(&sbi->gc_mutex);
 551         mutex_init(&sbi->write_inode);
 552         mutex_init(&sbi->writepages);
 553         mutex_init(&sbi->cp_mutex);
 554         for (i = 0; i < NR_LOCK_TYPE; i++)
 555                 mutex_init(&sbi->fs_lock[i]);
 556         sbi->por_doing = 0;
 557         spin_lock_init(&sbi->stat_lock);
 558         init_rwsem(&sbi->bio_sem);
 559         init_sb_info(sbi);
 560
 561         /* get an inode for meta space */
 562         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 563         if (IS_ERR(sbi->meta_inode)) {
 564                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 565                 err = PTR_ERR(sbi->meta_inode);
 566                 goto free_sb_buf;
 567         }
 568
 569         err = get_valid_checkpoint(sbi);
 570         if (err) {
 571                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 572                 goto free_meta_inode;
 573         }
 574
 575         /* sanity checking of checkpoint */
 576         err = -EINVAL;
 577         if (sanity_check_ckpt(sbi)) {
 578                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 579                 goto free_cp;
 580         }
 581
 582         sbi->total_valid_node_count =
 583                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 584         sbi->total_valid_inode_count =
 585                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 586         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 587         sbi->total_valid_block_count =
 588                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 589         sbi->last_valid_block_count = sbi->total_valid_block_count;
 590         sbi->alloc_valid_block_count = 0;
 591         INIT_LIST_HEAD(&sbi->dir_inode_list);
 592         spin_lock_init(&sbi->dir_inode_lock);
 593
 594         init_orphan_info(sbi);
 595
 596         /* setup f2fs internal modules */
 597         err = build_segment_manager(sbi);
 598         if (err) {
 599                 f2fs_msg(sb, KERN_ERR,
 600                         "Failed to initialize F2FS segment manager");
 601                 goto free_sm;
 602         }
 603         err = build_node_manager(sbi);
 604         if (err) {
 605                 f2fs_msg(sb, KERN_ERR,
 606                         "Failed to initialize F2FS node manager");
 607                 goto free_nm;
 608         }
 609
 610         build_gc_manager(sbi);
 611
 612         /* get an inode for node space */
 613         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
 614         if (IS_ERR(sbi->node_inode)) {
 615                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
 616                 err = PTR_ERR(sbi->node_inode);
 617                 goto free_nm;
 618         }
 619
 620         /* if there are nt orphan nodes free them */
 621         err = -EINVAL;
 622         if (recover_orphan_inodes(sbi))
 623                 goto free_node_inode;
 624
 625         /* read root inode and dentry */
 626         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
 627         if (IS_ERR(root)) {
 628                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
 629                 err = PTR_ERR(root);
 630                 goto free_node_inode;
 631         }
 632         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
 633                 goto free_root_inode;
 634
 635         sb->s_root = d_make_root(root); /* allocate root dentry */
 636         if (!sb->s_root) {
 637                 err = -ENOMEM;
 638                 goto free_root_inode;
 639         }
 640
 641         /* recover fsynced data */
 642         if (!test_opt(sbi, DISABLE_ROLL_FORWARD))
 643                 recover_fsync_data(sbi);
 644
 645         /* After POR, we can run background GC thread */
 646         err = start_gc_thread(sbi);
 647         if (err)
 648                 goto fail;
 649
 650         err = f2fs_build_stats(sbi);
 651         if (err)
 652                 goto fail;
 653
 654         if (test_opt(sbi, DISCARD)) {
 655                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 656                 if (!blk_queue_discard(q))
 657                         f2fs_msg(sb, KERN_WARNING,
 658                                         "mounting with \"discard\" option, but "
 659                                         "the device does not support discard");
 660         }
 661
 662         return 0;
 663 fail:
 664         stop_gc_thread(sbi);
 665 free_root_inode:
 666         dput(sb->s_root);
 667         sb->s_root = NULL;
 668 free_node_inode:
 669         iput(sbi->node_inode);
 670 free_nm:
 671         destroy_node_manager(sbi);
 672 free_sm:
 673         destroy_segment_manager(sbi);
 674 free_cp:
 675         kfree(sbi->ckpt);
 676 free_meta_inode:
 677         make_bad_inode(sbi->meta_inode);
 678         iput(sbi->meta_inode);
 679 free_sb_buf:
 680         brelse(raw_super_buf);
 681 free_sbi:
 682         kfree(sbi);
 683         return err;
 684 }
 685
 686 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
 687                         const char *dev_name, void *data)
 688 {
 689         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
 690 }
 691
 692 static struct file_system_type f2fs_fs_type = {
 693         .owner          = THIS_MODULE,
 694         .name           = "f2fs",
 695         .mount          = f2fs_mount,
 696         .kill_sb        = kill_block_super,
 697         .fs_flags       = FS_REQUIRES_DEV,
 698 };
 699
 700 static int __init init_inodecache(void)
 701 {
 702         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
 703                         sizeof(struct f2fs_inode_info), NULL);
 704         if (f2fs_inode_cachep == NULL)
 705                 return -ENOMEM;
 706         return 0;
 707 }
 708
 709 static void destroy_inodecache(void)
 710 {
 711         /*
 712          * Make sure all delayed rcu free inodes are flushed before we
 713          * destroy cache.
 714          */
 715         rcu_barrier();
 716         kmem_cache_destroy(f2fs_inode_cachep);
 717 }
 718
 719 static int __init init_f2fs_fs(void)
 720 {
 721         int err;
 722
 723         err = init_inodecache();
 724         if (err)
 725                 goto fail;
 726         err = create_node_manager_caches();
 727         if (err)
 728                 goto fail;
 729         err = create_gc_caches();
 730         if (err)
 731                 goto fail;
 732         err = create_checkpoint_caches();
 733         if (err)
 734                 goto fail;
 735         err = register_filesystem(&f2fs_fs_type);
 736         if (err)
 737                 goto fail;
 738         f2fs_create_root_stats();
 739 fail:
 740         return err;
 741 }
 742
 743 static void __exit exit_f2fs_fs(void)
 744 {
 745         f2fs_destroy_root_stats();
 746         unregister_filesystem(&f2fs_fs_type);
 747         destroy_checkpoint_caches();
 748         destroy_gc_caches();
 749         destroy_node_manager_caches();
 750         destroy_inodecache();
 751 }
 752
 753 module_init(init_f2fs_fs)
 754 module_exit(exit_f2fs_fs)
 755
 756 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
 757 MODULE_DESCRIPTION("Flash Friendly File System");
 758 MODULE_LICENSE("GPL");