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/buffer_head.h>
  16 #include <linux/backing-dev.h>
  17 #include <linux/kthread.h>
  18 #include <linux/parser.h>
  19 #include <linux/mount.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/random.h>
  23 #include <linux/exportfs.h>
  24 #include <linux/blkdev.h>
  25 #include <linux/f2fs_fs.h>
  26 #include <linux/sysfs.h>
  27
  28 #include "f2fs.h"
  29 #include "node.h"
  30 #include "segment.h"
  31 #include "xattr.h"
  32 #include "gc.h"
  33
  34 #define CREATE_TRACE_POINTS
  35 #include <trace/events/f2fs.h>
  36
  37 static struct proc_dir_entry *f2fs_proc_root;
  38 static struct kmem_cache *f2fs_inode_cachep;
  39 static struct kset *f2fs_kset;
  40
  41 enum {
  42         Opt_gc_background,
  43         Opt_disable_roll_forward,
  44         Opt_discard,
  45         Opt_noheap,
  46         Opt_user_xattr,
  47         Opt_nouser_xattr,
  48         Opt_acl,
  49         Opt_noacl,
  50         Opt_active_logs,
  51         Opt_disable_ext_identify,
  52         Opt_inline_xattr,
  53         Opt_inline_data,
  54         Opt_flush_merge,
  55         Opt_nobarrier,
  56         Opt_err,
  57 };
  58
  59 static match_table_t f2fs_tokens = {
  60         {Opt_gc_background, "background_gc=%s"},
  61         {Opt_disable_roll_forward, "disable_roll_forward"},
  62         {Opt_discard, "discard"},
  63         {Opt_noheap, "no_heap"},
  64         {Opt_user_xattr, "user_xattr"},
  65         {Opt_nouser_xattr, "nouser_xattr"},
  66         {Opt_acl, "acl"},
  67         {Opt_noacl, "noacl"},
  68         {Opt_active_logs, "active_logs=%u"},
  69         {Opt_disable_ext_identify, "disable_ext_identify"},
  70         {Opt_inline_xattr, "inline_xattr"},
  71         {Opt_inline_data, "inline_data"},
  72         {Opt_flush_merge, "flush_merge"},
  73         {Opt_nobarrier, "nobarrier"},
  74         {Opt_err, NULL},
  75 };
  76
  77 /* Sysfs support for f2fs */
  78 enum {
  79         GC_THREAD,      /* struct f2fs_gc_thread */
  80         SM_INFO,        /* struct f2fs_sm_info */
  81         NM_INFO,        /* struct f2fs_nm_info */
  82         F2FS_SBI,       /* struct f2fs_sb_info */
  83 };
  84
  85 struct f2fs_attr {
  86         struct attribute attr;
  87         ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
  88         ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
  89                          const char *, size_t);
  90         int struct_type;
  91         int offset;
  92 };
  93
  94 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
  95 {
  96         if (struct_type == GC_THREAD)
  97                 return (unsigned char *)sbi->gc_thread;
  98         else if (struct_type == SM_INFO)
  99                 return (unsigned char *)SM_I(sbi);
 100         else if (struct_type == NM_INFO)
 101                 return (unsigned char *)NM_I(sbi);
 102         else if (struct_type == F2FS_SBI)
 103                 return (unsigned char *)sbi;
 104         return NULL;
 105 }
 106
 107 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 108                         struct f2fs_sb_info *sbi, char *buf)
 109 {
 110         unsigned char *ptr = NULL;
 111         unsigned int *ui;
 112
 113         ptr = __struct_ptr(sbi, a->struct_type);
 114         if (!ptr)
 115                 return -EINVAL;
 116
 117         ui = (unsigned int *)(ptr + a->offset);
 118
 119         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
 120 }
 121
 122 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
 123                         struct f2fs_sb_info *sbi,
 124                         const char *buf, size_t count)
 125 {
 126         unsigned char *ptr;
 127         unsigned long t;
 128         unsigned int *ui;
 129         ssize_t ret;
 130
 131         ptr = __struct_ptr(sbi, a->struct_type);
 132         if (!ptr)
 133                 return -EINVAL;
 134
 135         ui = (unsigned int *)(ptr + a->offset);
 136
 137         ret = kstrtoul(skip_spaces(buf), 0, &t);
 138         if (ret < 0)
 139                 return ret;
 140         *ui = t;
 141         return count;
 142 }
 143
 144 static ssize_t f2fs_attr_show(struct kobject *kobj,
 145                                 struct attribute *attr, char *buf)
 146 {
 147         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 148                                                                 s_kobj);
 149         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 150
 151         return a->show ? a->show(a, sbi, buf) : 0;
 152 }
 153
 154 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
 155                                                 const char *buf, size_t len)
 156 {
 157         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 158                                                                         s_kobj);
 159         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 160
 161         return a->store ? a->store(a, sbi, buf, len) : 0;
 162 }
 163
 164 static void f2fs_sb_release(struct kobject *kobj)
 165 {
 166         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 167                                                                 s_kobj);
 168         complete(&sbi->s_kobj_unregister);
 169 }
 170
 171 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
 172 static struct f2fs_attr f2fs_attr_##_name = {                   \
 173         .attr = {.name = __stringify(_name), .mode = _mode },   \
 174         .show   = _show,                                        \
 175         .store  = _store,                                       \
 176         .struct_type = _struct_type,                            \
 177         .offset = _offset                                       \
 178 }
 179
 180 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)    \
 181         F2FS_ATTR_OFFSET(struct_type, name, 0644,               \
 182                 f2fs_sbi_show, f2fs_sbi_store,                  \
 183                 offsetof(struct struct_name, elname))
 184
 185 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
 186 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
 187 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
 188 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
 189 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
 190 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
 191 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
 192 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
 193 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
 194 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
 195 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
 196 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
 197
 198 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 199 static struct attribute *f2fs_attrs[] = {
 200         ATTR_LIST(gc_min_sleep_time),
 201         ATTR_LIST(gc_max_sleep_time),
 202         ATTR_LIST(gc_no_gc_sleep_time),
 203         ATTR_LIST(gc_idle),
 204         ATTR_LIST(reclaim_segments),
 205         ATTR_LIST(max_small_discards),
 206         ATTR_LIST(ipu_policy),
 207         ATTR_LIST(min_ipu_util),
 208         ATTR_LIST(min_fsync_blocks),
 209         ATTR_LIST(max_victim_search),
 210         ATTR_LIST(dir_level),
 211         ATTR_LIST(ram_thresh),
 212         NULL,
 213 };
 214
 215 static const struct sysfs_ops f2fs_attr_ops = {
 216         .show   = f2fs_attr_show,
 217         .store  = f2fs_attr_store,
 218 };
 219
 220 static struct kobj_type f2fs_ktype = {
 221         .default_attrs  = f2fs_attrs,
 222         .sysfs_ops      = &f2fs_attr_ops,
 223         .release        = f2fs_sb_release,
 224 };
 225
 226 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
 227 {
 228         struct va_format vaf;
 229         va_list args;
 230
 231         va_start(args, fmt);
 232         vaf.fmt = fmt;
 233         vaf.va = &args;
 234         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
 235         va_end(args);
 236 }
 237
 238 static void init_once(void *foo)
 239 {
 240         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
 241
 242         inode_init_once(&fi->vfs_inode);
 243 }
 244
 245 static int parse_options(struct super_block *sb, char *options)
 246 {
 247         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 248         substring_t args[MAX_OPT_ARGS];
 249         char *p, *name;
 250         int arg = 0;
 251
 252         if (!options)
 253                 return 0;
 254
 255         while ((p = strsep(&options, ",")) != NULL) {
 256                 int token;
 257                 if (!*p)
 258                         continue;
 259                 /*
 260                  * Initialize args struct so we know whether arg was
 261                  * found; some options take optional arguments.
 262                  */
 263                 args[0].to = args[0].from = NULL;
 264                 token = match_token(p, f2fs_tokens, args);
 265
 266                 switch (token) {
 267                 case Opt_gc_background:
 268                         name = match_strdup(&args[0]);
 269
 270                         if (!name)
 271                                 return -ENOMEM;
 272                         if (strlen(name) == 2 && !strncmp(name, "on", 2))
 273                                 set_opt(sbi, BG_GC);
 274                         else if (strlen(name) == 3 && !strncmp(name, "off", 3))
 275                                 clear_opt(sbi, BG_GC);
 276                         else {
 277                                 kfree(name);
 278                                 return -EINVAL;
 279                         }
 280                         kfree(name);
 281                         break;
 282                 case Opt_disable_roll_forward:
 283                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 284                         break;
 285                 case Opt_discard:
 286                         set_opt(sbi, DISCARD);
 287                         break;
 288                 case Opt_noheap:
 289                         set_opt(sbi, NOHEAP);
 290                         break;
 291 #ifdef CONFIG_F2FS_FS_XATTR
 292                 case Opt_user_xattr:
 293                         set_opt(sbi, XATTR_USER);
 294                         break;
 295                 case Opt_nouser_xattr:
 296                         clear_opt(sbi, XATTR_USER);
 297                         break;
 298                 case Opt_inline_xattr:
 299                         set_opt(sbi, INLINE_XATTR);
 300                         break;
 301 #else
 302                 case Opt_user_xattr:
 303                         f2fs_msg(sb, KERN_INFO,
 304                                 "user_xattr options not supported");
 305                         break;
 306                 case Opt_nouser_xattr:
 307                         f2fs_msg(sb, KERN_INFO,
 308                                 "nouser_xattr options not supported");
 309                         break;
 310                 case Opt_inline_xattr:
 311                         f2fs_msg(sb, KERN_INFO,
 312                                 "inline_xattr options not supported");
 313                         break;
 314 #endif
 315 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 316                 case Opt_acl:
 317                         set_opt(sbi, POSIX_ACL);
 318                         break;
 319                 case Opt_noacl:
 320                         clear_opt(sbi, POSIX_ACL);
 321                         break;
 322 #else
 323                 case Opt_acl:
 324                         f2fs_msg(sb, KERN_INFO, "acl options not supported");
 325                         break;
 326                 case Opt_noacl:
 327                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 328                         break;
 329 #endif
 330                 case Opt_active_logs:
 331                         if (args->from && match_int(args, &arg))
 332                                 return -EINVAL;
 333                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 334                                 return -EINVAL;
 335                         sbi->active_logs = arg;
 336                         break;
 337                 case Opt_disable_ext_identify:
 338                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 339                         break;
 340                 case Opt_inline_data:
 341                         set_opt(sbi, INLINE_DATA);
 342                         break;
 343                 case Opt_flush_merge:
 344                         set_opt(sbi, FLUSH_MERGE);
 345                         break;
 346                 case Opt_nobarrier:
 347                         set_opt(sbi, NOBARRIER);
 348                         break;
 349                 default:
 350                         f2fs_msg(sb, KERN_ERR,
 351                                 "Unrecognized mount option \"%s\" or missing value",
 352                                 p);
 353                         return -EINVAL;
 354                 }
 355         }
 356         return 0;
 357 }
 358
 359 static struct inode *f2fs_alloc_inode(struct super_block *sb)
 360 {
 361         struct f2fs_inode_info *fi;
 362
 363         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
 364         if (!fi)
 365                 return NULL;
 366
 367         init_once((void *) fi);
 368
 369         /* Initialize f2fs-specific inode info */
 370         fi->vfs_inode.i_version = 1;
 371         atomic_set(&fi->dirty_pages, 0);
 372         fi->i_current_depth = 1;
 373         fi->i_advise = 0;
 374         rwlock_init(&fi->ext.ext_lock);
 375         init_rwsem(&fi->i_sem);
 376
 377         set_inode_flag(fi, FI_NEW_INODE);
 378
 379         if (test_opt(F2FS_SB(sb), INLINE_XATTR))
 380                 set_inode_flag(fi, FI_INLINE_XATTR);
 381
 382         /* Will be used by directory only */
 383         fi->i_dir_level = F2FS_SB(sb)->dir_level;
 384
 385         return &fi->vfs_inode;
 386 }
 387
 388 static int f2fs_drop_inode(struct inode *inode)
 389 {
 390         /*
 391          * This is to avoid a deadlock condition like below.
 392          * writeback_single_inode(inode)
 393          *  - f2fs_write_data_page
 394          *    - f2fs_gc -> iput -> evict
 395          *       - inode_wait_for_writeback(inode)
 396          */
 397         if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
 398                 return 0;
 399         return generic_drop_inode(inode);
 400 }
 401
 402 /*
 403  * f2fs_dirty_inode() is called from __mark_inode_dirty()
 404  *
 405  * We should call set_dirty_inode to write the dirty inode through write_inode.
 406  */
 407 static void f2fs_dirty_inode(struct inode *inode, int flags)
 408 {
 409         set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
 410 }
 411
 412 static void f2fs_i_callback(struct rcu_head *head)
 413 {
 414         struct inode *inode = container_of(head, struct inode, i_rcu);
 415         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 416 }
 417
 418 static void f2fs_destroy_inode(struct inode *inode)
 419 {
 420         call_rcu(&inode->i_rcu, f2fs_i_callback);
 421 }
 422
 423 static void f2fs_put_super(struct super_block *sb)
 424 {
 425         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 426
 427         if (sbi->s_proc) {
 428                 remove_proc_entry("segment_info", sbi->s_proc);
 429                 remove_proc_entry(sb->s_id, f2fs_proc_root);
 430         }
 431         kobject_del(&sbi->s_kobj);
 432
 433         f2fs_destroy_stats(sbi);
 434         stop_gc_thread(sbi);
 435
 436         /* We don't need to do checkpoint when it's clean */
 437         if (sbi->s_dirty)
 438                 write_checkpoint(sbi, true);
 439
 440         /*
 441          * normally superblock is clean, so we need to release this.
 442          * In addition, EIO will skip do checkpoint, we need this as well.
 443          */
 444         release_dirty_inode(sbi);
 445
 446         iput(sbi->node_inode);
 447         iput(sbi->meta_inode);
 448
 449         /* destroy f2fs internal modules */
 450         destroy_node_manager(sbi);
 451         destroy_segment_manager(sbi);
 452
 453         kfree(sbi->ckpt);
 454         kobject_put(&sbi->s_kobj);
 455         wait_for_completion(&sbi->s_kobj_unregister);
 456
 457         sb->s_fs_info = NULL;
 458         brelse(sbi->raw_super_buf);
 459         kfree(sbi);
 460 }
 461
 462 int f2fs_sync_fs(struct super_block *sb, int sync)
 463 {
 464         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 465
 466         trace_f2fs_sync_fs(sb, sync);
 467
 468         if (sync) {
 469                 mutex_lock(&sbi->gc_mutex);
 470                 write_checkpoint(sbi, false);
 471                 mutex_unlock(&sbi->gc_mutex);
 472         } else {
 473                 f2fs_balance_fs(sbi);
 474         }
 475
 476         return 0;
 477 }
 478
 479 static int f2fs_freeze(struct super_block *sb)
 480 {
 481         int err;
 482
 483         if (f2fs_readonly(sb))
 484                 return 0;
 485
 486         err = f2fs_sync_fs(sb, 1);
 487         return err;
 488 }
 489
 490 static int f2fs_unfreeze(struct super_block *sb)
 491 {
 492         return 0;
 493 }
 494
 495 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 496 {
 497         struct super_block *sb = dentry->d_sb;
 498         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 499         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 500         block_t total_count, user_block_count, start_count, ovp_count;
 501
 502         total_count = le64_to_cpu(sbi->raw_super->block_count);
 503         user_block_count = sbi->user_block_count;
 504         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 505         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 506         buf->f_type = F2FS_SUPER_MAGIC;
 507         buf->f_bsize = sbi->blocksize;
 508
 509         buf->f_blocks = total_count - start_count;
 510         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 511         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 512
 513         buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
 514         buf->f_ffree = buf->f_files - valid_inode_count(sbi);
 515
 516         buf->f_namelen = F2FS_NAME_LEN;
 517         buf->f_fsid.val[0] = (u32)id;
 518         buf->f_fsid.val[1] = (u32)(id >> 32);
 519
 520         return 0;
 521 }
 522
 523 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 524 {
 525         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 526
 527         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
 528                 seq_printf(seq, ",background_gc=%s", "on");
 529         else
 530                 seq_printf(seq, ",background_gc=%s", "off");
 531         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 532                 seq_puts(seq, ",disable_roll_forward");
 533         if (test_opt(sbi, DISCARD))
 534                 seq_puts(seq, ",discard");
 535         if (test_opt(sbi, NOHEAP))
 536                 seq_puts(seq, ",no_heap_alloc");
 537 #ifdef CONFIG_F2FS_FS_XATTR
 538         if (test_opt(sbi, XATTR_USER))
 539                 seq_puts(seq, ",user_xattr");
 540         else
 541                 seq_puts(seq, ",nouser_xattr");
 542         if (test_opt(sbi, INLINE_XATTR))
 543                 seq_puts(seq, ",inline_xattr");
 544 #endif
 545 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 546         if (test_opt(sbi, POSIX_ACL))
 547                 seq_puts(seq, ",acl");
 548         else
 549                 seq_puts(seq, ",noacl");
 550 #endif
 551         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 552                 seq_puts(seq, ",disable_ext_identify");
 553         if (test_opt(sbi, INLINE_DATA))
 554                 seq_puts(seq, ",inline_data");
 555         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
 556                 seq_puts(seq, ",flush_merge");
 557         if (test_opt(sbi, NOBARRIER))
 558                 seq_puts(seq, ",nobarrier");
 559         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 560
 561         return 0;
 562 }
 563
 564 static int segment_info_seq_show(struct seq_file *seq, void *offset)
 565 {
 566         struct super_block *sb = seq->private;
 567         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 568         unsigned int total_segs =
 569                         le32_to_cpu(sbi->raw_super->segment_count_main);
 570         int i;
 571
 572         seq_puts(seq, "format: segment_type|valid_blocks\n"
 573                 "segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
 574
 575         for (i = 0; i < total_segs; i++) {
 576                 struct seg_entry *se = get_seg_entry(sbi, i);
 577
 578                 if ((i % 10) == 0)
 579                         seq_printf(seq, "%-5d", i);
 580                 seq_printf(seq, "%d|%-3u", se->type,
 581                                         get_valid_blocks(sbi, i, 1));
 582                 if ((i % 10) == 9 || i == (total_segs - 1))
 583                         seq_putc(seq, '\n');
 584                 else
 585                         seq_putc(seq, ' ');
 586         }
 587
 588         return 0;
 589 }
 590
 591 static int segment_info_open_fs(struct inode *inode, struct file *file)
 592 {
 593         return single_open(file, segment_info_seq_show, PDE_DATA(inode));
 594 }
 595
 596 static const struct file_operations f2fs_seq_segment_info_fops = {
 597         .owner = THIS_MODULE,
 598         .open = segment_info_open_fs,
 599         .read = seq_read,
 600         .llseek = seq_lseek,
 601         .release = single_release,
 602 };
 603
 604 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 605 {
 606         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 607         struct f2fs_mount_info org_mount_opt;
 608         int err, active_logs;
 609         bool need_restart_gc = false;
 610         bool need_stop_gc = false;
 611
 612         sync_filesystem(sb);
 613
 614         /*
 615          * Save the old mount options in case we
 616          * need to restore them.
 617          */
 618         org_mount_opt = sbi->mount_opt;
 619         active_logs = sbi->active_logs;
 620
 621         /* parse mount options */
 622         err = parse_options(sb, data);
 623         if (err)
 624                 goto restore_opts;
 625
 626         /*
 627          * Previous and new state of filesystem is RO,
 628          * so skip checking GC and FLUSH_MERGE conditions.
 629          */
 630         if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
 631                 goto skip;
 632
 633         /*
 634          * We stop the GC thread if FS is mounted as RO
 635          * or if background_gc = off is passed in mount
 636          * option. Also sync the filesystem.
 637          */
 638         if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
 639                 if (sbi->gc_thread) {
 640                         stop_gc_thread(sbi);
 641                         f2fs_sync_fs(sb, 1);
 642                         need_restart_gc = true;
 643                 }
 644         } else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
 645                 err = start_gc_thread(sbi);
 646                 if (err)
 647                         goto restore_opts;
 648                 need_stop_gc = true;
 649         }
 650
 651         /*
 652          * We stop issue flush thread if FS is mounted as RO
 653          * or if flush_merge is not passed in mount option.
 654          */
 655         if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
 656                 destroy_flush_cmd_control(sbi);
 657         } else if (test_opt(sbi, FLUSH_MERGE) && !SM_I(sbi)->cmd_control_info) {
 658                 err = create_flush_cmd_control(sbi);
 659                 if (err)
 660                         goto restore_gc;
 661         }
 662 skip:
 663         /* Update the POSIXACL Flag */
 664          sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 665                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 666         return 0;
 667 restore_gc:
 668         if (need_restart_gc) {
 669                 if (start_gc_thread(sbi))
 670                         f2fs_msg(sbi->sb, KERN_WARNING,
 671                                 "background gc thread has stopped");
 672         } else if (need_stop_gc) {
 673                 stop_gc_thread(sbi);
 674         }
 675 restore_opts:
 676         sbi->mount_opt = org_mount_opt;
 677         sbi->active_logs = active_logs;
 678         return err;
 679 }
 680
 681 static struct super_operations f2fs_sops = {
 682         .alloc_inode    = f2fs_alloc_inode,
 683         .drop_inode     = f2fs_drop_inode,
 684         .destroy_inode  = f2fs_destroy_inode,
 685         .write_inode    = f2fs_write_inode,
 686         .dirty_inode    = f2fs_dirty_inode,
 687         .show_options   = f2fs_show_options,
 688         .evict_inode    = f2fs_evict_inode,
 689         .put_super      = f2fs_put_super,
 690         .sync_fs        = f2fs_sync_fs,
 691         .freeze_fs      = f2fs_freeze,
 692         .unfreeze_fs    = f2fs_unfreeze,
 693         .statfs         = f2fs_statfs,
 694         .remount_fs     = f2fs_remount,
 695 };
 696
 697 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 698                 u64 ino, u32 generation)
 699 {
 700         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 701         struct inode *inode;
 702
 703         if (check_nid_range(sbi, ino))
 704                 return ERR_PTR(-ESTALE);
 705
 706         /*
 707          * f2fs_iget isn't quite right if the inode is currently unallocated!
 708          * However f2fs_iget currently does appropriate checks to handle stale
 709          * inodes so everything is OK.
 710          */
 711         inode = f2fs_iget(sb, ino);
 712         if (IS_ERR(inode))
 713                 return ERR_CAST(inode);
 714         if (unlikely(generation && inode->i_generation != generation)) {
 715                 /* we didn't find the right inode.. */
 716                 iput(inode);
 717                 return ERR_PTR(-ESTALE);
 718         }
 719         return inode;
 720 }
 721
 722 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 723                 int fh_len, int fh_type)
 724 {
 725         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 726                                     f2fs_nfs_get_inode);
 727 }
 728
 729 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 730                 int fh_len, int fh_type)
 731 {
 732         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 733                                     f2fs_nfs_get_inode);
 734 }
 735
 736 static const struct export_operations f2fs_export_ops = {
 737         .fh_to_dentry = f2fs_fh_to_dentry,
 738         .fh_to_parent = f2fs_fh_to_parent,
 739         .get_parent = f2fs_get_parent,
 740 };
 741
 742 static loff_t max_file_size(unsigned bits)
 743 {
 744         loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
 745         loff_t leaf_count = ADDRS_PER_BLOCK;
 746
 747         /* two direct node blocks */
 748         result += (leaf_count * 2);
 749
 750         /* two indirect node blocks */
 751         leaf_count *= NIDS_PER_BLOCK;
 752         result += (leaf_count * 2);
 753
 754         /* one double indirect node block */
 755         leaf_count *= NIDS_PER_BLOCK;
 756         result += leaf_count;
 757
 758         result <<= bits;
 759         return result;
 760 }
 761
 762 static int sanity_check_raw_super(struct super_block *sb,
 763                         struct f2fs_super_block *raw_super)
 764 {
 765         unsigned int blocksize;
 766
 767         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 768                 f2fs_msg(sb, KERN_INFO,
 769                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 770                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 771                 return 1;
 772         }
 773
 774         /* Currently, support only 4KB page cache size */
 775         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 776                 f2fs_msg(sb, KERN_INFO,
 777                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 778                         PAGE_CACHE_SIZE);
 779                 return 1;
 780         }
 781
 782         /* Currently, support only 4KB block size */
 783         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 784         if (blocksize != F2FS_BLKSIZE) {
 785                 f2fs_msg(sb, KERN_INFO,
 786                         "Invalid blocksize (%u), supports only 4KB\n",
 787                         blocksize);
 788                 return 1;
 789         }
 790
 791         if (le32_to_cpu(raw_super->log_sectorsize) !=
 792                                         F2FS_LOG_SECTOR_SIZE) {
 793                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 794                 return 1;
 795         }
 796         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 797                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 798                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 799                 return 1;
 800         }
 801         return 0;
 802 }
 803
 804 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 805 {
 806         unsigned int total, fsmeta;
 807         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 808         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 809
 810         total = le32_to_cpu(raw_super->segment_count);
 811         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 812         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 813         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 814         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 815         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 816
 817         if (unlikely(fsmeta >= total))
 818                 return 1;
 819
 820         if (unlikely(f2fs_cp_error(sbi))) {
 821                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 822                 return 1;
 823         }
 824         return 0;
 825 }
 826
 827 static void init_sb_info(struct f2fs_sb_info *sbi)
 828 {
 829         struct f2fs_super_block *raw_super = sbi->raw_super;
 830         int i;
 831
 832         sbi->log_sectors_per_block =
 833                 le32_to_cpu(raw_super->log_sectors_per_block);
 834         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 835         sbi->blocksize = 1 << sbi->log_blocksize;
 836         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 837         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 838         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 839         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 840         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 841         sbi->total_node_count =
 842                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 843                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 844         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 845         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 846         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 847         sbi->cur_victim_sec = NULL_SECNO;
 848         sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
 849
 850         for (i = 0; i < NR_COUNT_TYPE; i++)
 851                 atomic_set(&sbi->nr_pages[i], 0);
 852
 853         sbi->dir_level = DEF_DIR_LEVEL;
 854         sbi->need_fsck = false;
 855 }
 856
 857 /*
 858  * Read f2fs raw super block.
 859  * Because we have two copies of super block, so read the first one at first,
 860  * if the first one is invalid, move to read the second one.
 861  */
 862 static int read_raw_super_block(struct super_block *sb,
 863                         struct f2fs_super_block **raw_super,
 864                         struct buffer_head **raw_super_buf)
 865 {
 866         int block = 0;
 867
 868 retry:
 869         *raw_super_buf = sb_bread(sb, block);
 870         if (!*raw_super_buf) {
 871                 f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
 872                                 block + 1);
 873                 if (block == 0) {
 874                         block++;
 875                         goto retry;
 876                 } else {
 877                         return -EIO;
 878                 }
 879         }
 880
 881         *raw_super = (struct f2fs_super_block *)
 882                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 883
 884         /* sanity checking of raw super */
 885         if (sanity_check_raw_super(sb, *raw_super)) {
 886                 brelse(*raw_super_buf);
 887                 f2fs_msg(sb, KERN_ERR,
 888                         "Can't find valid F2FS filesystem in %dth superblock",
 889                                                                 block + 1);
 890                 if (block == 0) {
 891                         block++;
 892                         goto retry;
 893                 } else {
 894                         return -EINVAL;
 895                 }
 896         }
 897
 898         return 0;
 899 }
 900
 901 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 902 {
 903         struct f2fs_sb_info *sbi;
 904         struct f2fs_super_block *raw_super;
 905         struct buffer_head *raw_super_buf;
 906         struct inode *root;
 907         long err = -EINVAL;
 908         bool retry = true;
 909         int i;
 910
 911 try_onemore:
 912         /* allocate memory for f2fs-specific super block info */
 913         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 914         if (!sbi)
 915                 return -ENOMEM;
 916
 917         /* set a block size */
 918         if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
 919                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 920                 goto free_sbi;
 921         }
 922
 923         err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
 924         if (err)
 925                 goto free_sbi;
 926
 927         sb->s_fs_info = sbi;
 928         /* init some FS parameters */
 929         sbi->active_logs = NR_CURSEG_TYPE;
 930
 931         set_opt(sbi, BG_GC);
 932
 933 #ifdef CONFIG_F2FS_FS_XATTR
 934         set_opt(sbi, XATTR_USER);
 935 #endif
 936 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 937         set_opt(sbi, POSIX_ACL);
 938 #endif
 939         /* parse mount options */
 940         err = parse_options(sb, (char *)data);
 941         if (err)
 942                 goto free_sb_buf;
 943
 944         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 945         sb->s_max_links = F2FS_LINK_MAX;
 946         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 947
 948         sb->s_op = &f2fs_sops;
 949         sb->s_xattr = f2fs_xattr_handlers;
 950         sb->s_export_op = &f2fs_export_ops;
 951         sb->s_magic = F2FS_SUPER_MAGIC;
 952         sb->s_time_gran = 1;
 953         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 954                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 955         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 956
 957         /* init f2fs-specific super block info */
 958         sbi->sb = sb;
 959         sbi->raw_super = raw_super;
 960         sbi->raw_super_buf = raw_super_buf;
 961         mutex_init(&sbi->gc_mutex);
 962         mutex_init(&sbi->writepages);
 963         mutex_init(&sbi->cp_mutex);
 964         init_rwsem(&sbi->node_write);
 965         sbi->por_doing = false;
 966         spin_lock_init(&sbi->stat_lock);
 967
 968         init_rwsem(&sbi->read_io.io_rwsem);
 969         sbi->read_io.sbi = sbi;
 970         sbi->read_io.bio = NULL;
 971         for (i = 0; i < NR_PAGE_TYPE; i++) {
 972                 init_rwsem(&sbi->write_io[i].io_rwsem);
 973                 sbi->write_io[i].sbi = sbi;
 974                 sbi->write_io[i].bio = NULL;
 975         }
 976
 977         init_rwsem(&sbi->cp_rwsem);
 978         init_waitqueue_head(&sbi->cp_wait);
 979         init_sb_info(sbi);
 980
 981         /* get an inode for meta space */
 982         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 983         if (IS_ERR(sbi->meta_inode)) {
 984                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 985                 err = PTR_ERR(sbi->meta_inode);
 986                 goto free_sb_buf;
 987         }
 988
 989         err = get_valid_checkpoint(sbi);
 990         if (err) {
 991                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 992                 goto free_meta_inode;
 993         }
 994
 995         /* sanity checking of checkpoint */
 996         err = -EINVAL;
 997         if (sanity_check_ckpt(sbi)) {
 998                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 999                 goto free_cp;
1000         }
1001
1002         sbi->total_valid_node_count =
1003                                 le32_to_cpu(sbi->ckpt->valid_node_count);
1004         sbi->total_valid_inode_count =
1005                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
1006         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1007         sbi->total_valid_block_count =
1008                                 le64_to_cpu(sbi->ckpt->valid_block_count);
1009         sbi->last_valid_block_count = sbi->total_valid_block_count;
1010         sbi->alloc_valid_block_count = 0;
1011         INIT_LIST_HEAD(&sbi->dir_inode_list);
1012         spin_lock_init(&sbi->dir_inode_lock);
1013
1014         init_ino_entry_info(sbi);
1015
1016         /* setup f2fs internal modules */
1017         err = build_segment_manager(sbi);
1018         if (err) {
1019                 f2fs_msg(sb, KERN_ERR,
1020                         "Failed to initialize F2FS segment manager");
1021                 goto free_sm;
1022         }
1023         err = build_node_manager(sbi);
1024         if (err) {
1025                 f2fs_msg(sb, KERN_ERR,
1026                         "Failed to initialize F2FS node manager");
1027                 goto free_nm;
1028         }
1029
1030         build_gc_manager(sbi);
1031
1032         /* get an inode for node space */
1033         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1034         if (IS_ERR(sbi->node_inode)) {
1035                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1036                 err = PTR_ERR(sbi->node_inode);
1037                 goto free_nm;
1038         }
1039
1040         /* if there are nt orphan nodes free them */
1041         recover_orphan_inodes(sbi);
1042
1043         /* read root inode and dentry */
1044         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1045         if (IS_ERR(root)) {
1046                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1047                 err = PTR_ERR(root);
1048                 goto free_node_inode;
1049         }
1050         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1051                 iput(root);
1052                 err = -EINVAL;
1053                 goto free_node_inode;
1054         }
1055
1056         sb->s_root = d_make_root(root); /* allocate root dentry */
1057         if (!sb->s_root) {
1058                 err = -ENOMEM;
1059                 goto free_root_inode;
1060         }
1061
1062         err = f2fs_build_stats(sbi);
1063         if (err)
1064                 goto free_root_inode;
1065
1066         if (f2fs_proc_root)
1067                 sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1068
1069         if (sbi->s_proc)
1070                 proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1071                                  &f2fs_seq_segment_info_fops, sb);
1072
1073         if (test_opt(sbi, DISCARD)) {
1074                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1075                 if (!blk_queue_discard(q))
1076                         f2fs_msg(sb, KERN_WARNING,
1077                                         "mounting with \"discard\" option, but "
1078                                         "the device does not support discard");
1079         }
1080
1081         sbi->s_kobj.kset = f2fs_kset;
1082         init_completion(&sbi->s_kobj_unregister);
1083         err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1084                                                         "%s", sb->s_id);
1085         if (err)
1086                 goto free_proc;
1087
1088         if (!retry)
1089                 sbi->need_fsck = true;
1090
1091         /* recover fsynced data */
1092         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1093                 err = recover_fsync_data(sbi);
1094                 if (err) {
1095                         f2fs_msg(sb, KERN_ERR,
1096                                 "Cannot recover all fsync data errno=%ld", err);
1097                         goto free_kobj;
1098                 }
1099         }
1100
1101         /*
1102          * If filesystem is not mounted as read-only then
1103          * do start the gc_thread.
1104          */
1105         if (!f2fs_readonly(sb)) {
1106                 /* After POR, we can run background GC thread.*/
1107                 err = start_gc_thread(sbi);
1108                 if (err)
1109                         goto free_kobj;
1110         }
1111         return 0;
1112
1113 free_kobj:
1114         kobject_del(&sbi->s_kobj);
1115 free_proc:
1116         if (sbi->s_proc) {
1117                 remove_proc_entry("segment_info", sbi->s_proc);
1118                 remove_proc_entry(sb->s_id, f2fs_proc_root);
1119         }
1120         f2fs_destroy_stats(sbi);
1121 free_root_inode:
1122         dput(sb->s_root);
1123         sb->s_root = NULL;
1124 free_node_inode:
1125         iput(sbi->node_inode);
1126 free_nm:
1127         destroy_node_manager(sbi);
1128 free_sm:
1129         destroy_segment_manager(sbi);
1130 free_cp:
1131         kfree(sbi->ckpt);
1132 free_meta_inode:
1133         make_bad_inode(sbi->meta_inode);
1134         iput(sbi->meta_inode);
1135 free_sb_buf:
1136         brelse(raw_super_buf);
1137 free_sbi:
1138         kfree(sbi);
1139
1140         /* give only one another chance */
1141         if (retry) {
1142                 retry = 0;
1143                 shrink_dcache_sb(sb);
1144                 goto try_onemore;
1145         }
1146         return err;
1147 }
1148
1149 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1150                         const char *dev_name, void *data)
1151 {
1152         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1153 }
1154
1155 static struct file_system_type f2fs_fs_type = {
1156         .owner          = THIS_MODULE,
1157         .name           = "f2fs",
1158         .mount          = f2fs_mount,
1159         .kill_sb        = kill_block_super,
1160         .fs_flags       = FS_REQUIRES_DEV,
1161 };
1162 MODULE_ALIAS_FS("f2fs");
1163
1164 static int __init init_inodecache(void)
1165 {
1166         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1167                         sizeof(struct f2fs_inode_info));
1168         if (!f2fs_inode_cachep)
1169                 return -ENOMEM;
1170         return 0;
1171 }
1172
1173 static void destroy_inodecache(void)
1174 {
1175         /*
1176          * Make sure all delayed rcu free inodes are flushed before we
1177          * destroy cache.
1178          */
1179         rcu_barrier();
1180         kmem_cache_destroy(f2fs_inode_cachep);
1181 }
1182
1183 static int __init init_f2fs_fs(void)
1184 {
1185         int err;
1186
1187         err = init_inodecache();
1188         if (err)
1189                 goto fail;
1190         err = create_node_manager_caches();
1191         if (err)
1192                 goto free_inodecache;
1193         err = create_segment_manager_caches();
1194         if (err)
1195                 goto free_node_manager_caches;
1196         err = create_gc_caches();
1197         if (err)
1198                 goto free_segment_manager_caches;
1199         err = create_checkpoint_caches();
1200         if (err)
1201                 goto free_gc_caches;
1202         f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1203         if (!f2fs_kset) {
1204                 err = -ENOMEM;
1205                 goto free_checkpoint_caches;
1206         }
1207         err = register_filesystem(&f2fs_fs_type);
1208         if (err)
1209                 goto free_kset;
1210         f2fs_create_root_stats();
1211         f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1212         return 0;
1213
1214 free_kset:
1215         kset_unregister(f2fs_kset);
1216 free_checkpoint_caches:
1217         destroy_checkpoint_caches();
1218 free_gc_caches:
1219         destroy_gc_caches();
1220 free_segment_manager_caches:
1221         destroy_segment_manager_caches();
1222 free_node_manager_caches:
1223         destroy_node_manager_caches();
1224 free_inodecache:
1225         destroy_inodecache();
1226 fail:
1227         return err;
1228 }
1229
1230 static void __exit exit_f2fs_fs(void)
1231 {
1232         remove_proc_entry("fs/f2fs", NULL);
1233         f2fs_destroy_root_stats();
1234         unregister_filesystem(&f2fs_fs_type);
1235         destroy_checkpoint_caches();
1236         destroy_gc_caches();
1237         destroy_segment_manager_caches();
1238         destroy_node_manager_caches();
1239         destroy_inodecache();
1240         kset_unregister(f2fs_kset);
1241 }
1242
1243 module_init(init_f2fs_fs)
1244 module_exit(exit_f2fs_fs)
1245
1246 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1247 MODULE_DESCRIPTION("Flash Friendly File System");
1248 MODULE_LICENSE("GPL");